Growth of Li x La y Sr z MnO3 thin films by pulsed laser deposition: complex relation between thin film composition and deposition parameters

Li _x La _y Sr _z MnO₃ thin films of various compositions (x,y,z) have been grown using pulsed laser deposition. The compositions of the films have been studied as a function of deposition temperature, target-to-substrate distance and deposition pressure with respect to different cation ratios of the targets by inductively coupled plasma mass spectrometry. When growing multi-elemental oxide thin films containing lithium (with its large mass difference to other elements), lithium loss is most probably inevitable. But the desired thin film composition can be achieved by selecting specific growth conditions and different target compositions. The experiments also elucidate some of the mechanisms behind the incongruent lithium transfer from the targets to thin films.

How social intimidation interferred with the increasing number of improper accesses at the E.R.: a first-month COVID19 outbreak evaluation

SARS Cov 2 pandemic outbreak caused countless changes in the daily habits among people in the entire World. National Health Systems were highly stressed and at severe risk of collapse. In the first months of 2020, it was expected a worsening of the typical overcrowding working flow. Quite the opposite, we found out an unexpected decrease throughout the daily ED visits. We evaluated the ER visits of a University Metropolitan Hospital in Rome in March 2020, comparing them with the same month in 2019. We highlight the sharp decline in ED visits for deferrable urgencies, considered among the leading causes of ED overcrowding. On the contrary, the rate of visits for "time-dependent" pathologies is superimposable for those pathologies mainly centralized through the Out-of-Hospital Emergency System. In a historical period where significant outpatient activity restrictions took place, we expected an increase in ED visits for deferred emergencies. On the contrary, it was undergoing a considerable decrease. The critical decrease in accesses recorded in March 2020 can be considered an indicator of ED's improper use. Probably, the fear of a possible coronavirus-related infection might have to lead the population to refer to the ED just in case of real emergency condition or severe medical issues, as it should "normally" be. The critical decrease in accesses recorded in March 2020 can be considered an indicator of ED's improper use. We would highlight the need to sensitize people to proper use of Emergency Medical Services, avoiding overcrowding and overuse. This unexpected event, lead by a global pandemic, could help reorganize the whole Health System.

Magnesium sulphate in the Emergency Department: an old, new friend

With our study, we searched the medical literature to find magnesium (Mg) correlation with Emergency situations or its use in Emergency Medicine. Our aim is to fill the gap that we find in our daily routine between Mg studies on its role in Emergency and the real conception that doctors have of it in medical practice. We searched the literature for terms as magnesium or magnesium sulphate, magnesium in emergency, eclampsia, arrhythmias, acute asthma exacerbation, magnesium, and pediatric population. After a thorough research, we divided our discoveries into chapters to sort out a large amount often discordant articles.

Structure and chemistry of interfaces between ceria and yttria-stabilized zirconia studied by analytical STEM

Epitaxial undoped and Gd₂O₃-doped ceria films were grown by pulsed laser deposition on (1 1 1) faced Y₂O₃-stabilized zirconia (YSZ). Highly localized cerium reduction at the film-substrate interfaces is revealed by atomically resolved valence EELS mapping using C_s aberration-corrected scanning transmission electron microscopy. The chemical profiles reveal interdiffusion of Ce, (Gd), Y, Zr, forming an intermixing zone at the interface 7-9 (1 1 1) lattice planes wide. In its vicinity, the fraction of Ce³⁺ raises gradually over 6-8 lattice planes from zero in the bulk ceria to ≈100% in one single plane at the interface. Beyond this plane the Ce³⁺ fraction drops sharply within the YSZ substrate. In the vicinity of the interface systematic scan deflections are observed during EELS line scans. The advancing electron probe experiences a retarding force at the ceria side, and an accelerating force at the YSZ side, irrespective of the scan direction. This behavior is suggestive of coulombic interactions between the electron probe and a charged interface. This is interpreted as an indication of the presence of a space-charge situation at the YSZ/ceria interface, resulting from an excess negative charge at the ceria side (due to Ce³⁺cations) and an excess positive charge at the YSZ side (due to oxygen vacancies).

Safety and efficacy of low doses of diclofenac on acute pain in the emergency setting

Diclofenac is the most widely prescribed non-steroidal anti-inflammatory drug worldwide. Data collected during the last 10 years reported a dose-duration dependent increasing of cardiovascular risk associated with the use of diclofenac, supporting the evidence of a close association with the degree of COX-2 inhibition achieved in vivo. Nevertheless, the amplitude of cardiovascular risk associated with the administration of diclofenac at low doses and for the short-term duration is still poorly defined. Indeed, data did not show a clear and strong increasing of the risk for daily doses of 75 and of 50 mg. Concerning duration, while the identification of a safe temporal window is less defined, some studies reported an absence or a very low risk when the exposure is shorter than 30 days. Today, new low-dosage diclofenac formulations are available, allowing to reduce the systemic exposure, the degree of COX-2 inhibition and possibly the risk of occurrence of cardiovascular events. This is the reason why those new formulations may represent the ideal drug for the management of pain in the emergency setting.

Paracetamol-codeine compared to ketorolac for pain control in the Emergency Department

OBJECTIVE

Paracetamol /codeine has shown a strong analgesic activity in several studies conducted among different kind of subjects, including those with trauma. Nevertheless, its efficacy in patients accessing the Emergency Department (ED) for different kind of pain has never been tested.

PATIENTS AND METHODS

This is a cross-sectional, observational, prospective, cohort study. Inclusion criteria were patients > 18 year old presenting to the ED for localized traumatic or inflammatory pain involving only extremities. Numeric scale (NRS) was recorded thirty minutes and two hours after the administration of the analgesic therapy, consisting of 15 mg of ketorolac or 1000 mg/60 mg of paracetamol/ codeine, both orally.

RESULTS

Two-hundred patients were consecutively enrolled; 87 were treated with paracetamol/codeine and 113 with ketorolac. The combination paracetamol/codeine resulted to be not inferior to ketorolac in non-traumatic pain group and trauma group (p = 0.635 and p = 0.482, respectively). Compared to ketorolac, the combination paracetamol/codeine exerted a significantly higher analgesic activity in patients with fractures and muscular pain (p = 0.044) and was more effective in acute pain (p = 0.002), with a significant effect two hours after the administration (p = 0.029).

CONCLUSIONS

Paracetamol/codeine is equivalent to ketorolac in non-traumatic pain and post-traumatic pain, but is superior in acute pain and in patients with fractures and muscular pain. Those results play in favor of the use of the combination paracetamol/codeine in patients accessing the ED for non-traumatic or traumatic pain of the extremities.

Natriuretic peptides and atrial fibrillation

BACKGROUND AND OBJECTIVE

Atrial fibrillation (AF) is the most common arrhythmia in the medical practice, it is associated with an increased total and cardiovascular mortality, as well as cardiovascular morbidity, including stroke and heart failure. AF is encountered in different medical specialties including cardiology, family medicine and emergency medicine as well. Treatment goal is to minimize stroke risk but also taking into account the quality of life. Therefore rate or a rhythm control strategies must be carefully selected. This review focuses on natriuretic polypeptides (NPs) as potential useful markers in AF patients management.

EVIDENCE AND INFORMATION SOURCES

Pubmed was searched for natriuretic peptides and atrial fibrillation. Pertinent abstracts were reviewed by the Authors and the articles fully evaluated when considered pertinent.

STATE OF THE ART

NP biology and physiology is described and general application in heart failure outlined. With regard to AF, the role of NP as predictor of cardioversion is reviewed and discussed. Patients eligible for rhythm control not always respond to treatment. Classic markers for a suitable cardioversion, such an echocardiography, are not immediately available in most settings. NP might be a resource predicting cardioversion (or not) upon patient's presentation.

PROSPECTIVES

Biomarkers, such NPs, might be used to predict treatment response other than in heart failure.

CONCLUSIONS

In AF management, NT-ProBNP is a promising tool helping physicians to choose rhythm or rate control strategy.

Acetaminophen plus codeine compared to ketorolac in polytrauma patients

INTRODUCTION

The management of pain in polytrauma patients is mandatory. While non-steroidal anti-inflammatory drugs (NSAIDs) represent the most used drugs in polytrauma patients, their use may be associated with an increased risk of haemorrhage. Opioids may represent a valid alternative to NSAIDs either alone or in combination with acetaminophen. Whether their efficacy is comparable to that produced by NSAIDs in polytrauma patients has never been studied.

PATIENTS AND METHODS

60 polytrauma patients were enrolled for this study. 30 patients were treated with acetaminophen 1000 mg plus codeine 60 mg tid for 24 hours (Group A), while the remaining 30 with ketorolac 10 mg qid for 24 hours (Group B). Pain intensity has been evaluated using an analogical visual scale (VAS) ranging from 0 (no pain) to 10 (very severe pain). The level of pain was valuated at enrolment (TO) as well as after 2 (T2), 12 (T12) and 24 (T24) hours from the starting of the analgesic therapy. Results obtained by the group A were compared with those reported by the group B.

RESULTS

T0: Group A mean score was 6.4 +/- 1.5 compared with 6.6 +/- 1.5 of Group B (p= ns); T2: Group A mean score was 3.4 +/- 2.8, compared with 3.5 +/- 2.4 of group B (p = ns); T12: Group A mean score was 3.4 +/- 3.4, compared with 3.5 +/- 3 of Gorup B (p = ns); T24: Group A mean score was 2.9 +/- 1.5, compared to 3.0 +/- 1.6 of Group B (p = ns). All those drugs determined a significant reduction of pain intensity during the course of therapy.

CONCLUSIONS

Acetaminophen plus codeine is effective in pain control in polytrauma patients at least in our series. It may represent a valid alternative to NSAIDs, especially in patients with a documented haemorrhage or with a high hemorrhagic risk.

Heart rate variability and myocardial infarction: systematic literature review and metanalysis

BACKGROUND

Heart rate, measured as beat-to-beat intervals, is not constant and varies in time. This property is known as heart rate variability (HRV) and it has been investigated in several diseases, including myocardial infarction (MI). The main hypothesis is that HRV embed some physiological processes that are characteristics of regulatory systems acting on cardiovascular system. It is possible to quantify such a complex behaviour starting from RR intervals properties itself with the idea that any event affecting the cardiac regulatory system significantly will disrupt and change HRV. In this article, we first review different methodologies previously published to calculate HRV indexes. We then searched literature for studies published on HRV and MI and we derive a metanalysis where published data allow calculation of composite outcomes.

MATERIAL AND METHODS

Articles considered eligible for metanalysis were original retrospective/prospective studies investigating HRV after myocardial infarction, reporting follow up for mortality or significant cardiac complications. Random effect model was used to assessed for homogeneity and calculate composite outcome and its 95% confidence interval (CI).

RESULTS

21 studies were identified as eligible for subsequent analysis. Among these studies 5 large trials were eligible for metanalysis: "they included 3489 total post-MI patient with an overall mortality of 125/577 (21.7%) in patients with standard deviation of RR intervals (SDNN) less than 70 msec compared to 235/2912 (8.1%) in patients with SDNN > 70 msec". Metanalysis demonstrates that, after a MI, patients with SDNN below 70 msec on 24 hours ECG recording have almost 4 times more chance to die in the next 3 years.

CONCLUSION

Results from metanalysis and other studies considered (but not included in the analysis) are consistent with the final finding, that a disrupted HRV dynamic (low SDNN) is associated with higher adverse outcome. In this perspective, although data are strongly positive for a direct relationship between SDNN and mortality after MI, SDNN value must be considered carefully on a single patient. The primary purpose of the metanalysis was to address whether studies conducted on HRV and MI were consistent rather than established a cut-off for SDNN. HRV is simple, non invasive and relatively not expensive to obtain.

Postpartum thyroiditis is associated with fluctuations in transforming growth factor-beta1 serum levels

Postpartum thyroiditis (PPT) is characterized by a rapid evolution and recovery of euthyroidism. Therefore, it can represent a good model to study early cytokine fluctuations in autoimmune thyroid diseases. TGFbeta1 is an immunosuppressive cytokine, as it inhibits T and B cell proliferation, natural killer cell cytotoxic activity, and the generation of T cell cytotoxicity. The aim of this study was to assess serum concentrations of TGFbeta1 during pregnancy and to study possible serum fluctuations of this cytokine during the different phases of PPT. Thyroid biochemical pattern, antithyroid autoantibodies (ATA), and total and active TGFbeta1 (aTGFbeta1) serum concentrations were evaluated in 63 pregnant women. Thirty-four of them were ATA(+), and 29 were ATA(-). Twenty of the 34 ATA(+) women were followed in the postpartum year. Nine of these 20 women developed PPT; 11 remained euthyroid. All of the PPT women became euthyroid during the follow-up. Our results showed 1) detectable serum levels of aTGFbeta1 in 50% of ATA(+) pregnant women, suggesting that the presence of autoantibodies may characterize a favorable condition for TGFbeta1 activation; and 2) decreased total TGFbeta1 and increased aTGFbeta1 serum levels during the active phase of PPT in ATA(+) women. This seems to suggest that inflammation may be responsible for TGFbeta1 activation and autoantibody increase because of antigen release. Although further studies of women with persistent hypothyroidism after the postpartum year are needed, the possibility that the enhanced activation of TGFbeta1 may contribute to resolution of thyroid inflammation postpartum cannot be excluded.

[Goiter prevalence and urinary excretion of iodine in a sample of school age children in the city of Rome]

The aim of the study was the assessment of the urinary iodine excretion and the evaluation of thyroid volume compared with clinical examination in 1040 schoolchildren (6-14 years old), living in Rome. Mean urinary iodine excretion was 98.52 +/- 49.81 micrograms/l (median 92 micrograms/l). Thyroid enlargement, as assessed by palpation, was found to be grade 1A in 35.4% of the children, grade 1B in 9.6% and grade 2 in 0.2%. Thyroid volume, determined by ultrasound, increased with age, was significantly correlated with body surface area and was significantly higher in females, as compared to males, in the 11 and 12 years old group. Eleven children (1.9%) were negative at palpation (grade 0) but showed thyroid enlargement by ultrasound. The prevalence of goiter determined by ultrasound resulted to be 4.7%.

Specificity of proteolysis inhibitors in rabbit plasma

Hydrolysis and inhibition of hydrolysis of leucine enkephalin in Oryctolagus plasma were studied by kinetics and chromatographic techniques. By data obtained, in this species, enkephalins are degraded by the same enzymes active in other mammals: aminopeptidases, dipeptidylaminopeptidases, and dipeptidylcarboxypeptidases. At variance with data obtained in other species, where enkephalins are hydrolyzed mostly by aminopeptidases, in Oryctolagus Leu-enkephalin hydrolysis is mainly due to dipeptidylcarboxypeptidases, whereas aminopeptidases contribution is the minimum of all three enzyme groups. Comparative analyses performed in the presence and in the absence of plasma inhibitors indicate that the ability of these substances to reduce substratum hydrolysis is very limited. On the contrary, the specific hydrolysis pattern evidenced appears to originate primarily from selective inhibition of the three groups of enzymes. Results obtained appear consistent with a role of plasma inhibitors in tuning hydrolysis to specific substrata, without appreciably modifying the amount of the substratum degraded.

Early detection of nephrotoxic effects in thalassemic patients receiving desferrioxamine therapy

Nineteen transfusion-dependent beta-thalassemia major patients were included in the study. Six of these patients underwent chelation therapy with desferrioxamine by subcutaneous infusion (50 mg/kg/12 hr) and 13 received intravenous infusion (50 mg/kg/6 hr or 100 mg/kg/24 hr). BUN, creatinine, creatinine clearance, beta 2-microglobulin, urinary beta 2-microglobulin and urinary growth hormone excretion were evaluated during desferrioxamine treatment. Thirteen out of nineteen patients presented tubular damage indicated by increased excretion of urinary beta 2-microglobulin. 85% (11 of 13) of these patients showed more serious tubular damage, as demonstrated by concurrent increased urinary growth hormone excretion. Moreover, a positive correlation between urinary growth hormone excretion and urinary beta 2-microglobulin was observed (P < 0.05).

Enkephalin-degrading dipeptidylcarboxypeptidases in human and Cavia porcellus plasma

1. The dipeptidylcarboxypeptidases that degrade leucine enkephalin in human and guinea pig plasma were studied by kinetic and chromatographic techniques. 2. The extremely rapid degradation of enkephalins in Cavia plasma seems to be caused by both increased activity of enzymes and reduced role of inhibitors. 3. The increased role of dipeptidylcarboxypeptidases in Cavia as compared to Homo appears prevalently caused by the presence in the former species of a considerable number of very active enzymes. 4. The sum of these data indicates the existence of noticeable intraspecific differences either in peptide-degrading enzymes present in plasma, or in plasma peptides, or in both.

Thyroid hypofunction related with the progression of human immunodeficiency virus infection

Thyroid function was evaluated in 119 human immunodeficiency virus (HIV) infected patients at different stages of infection, compared with euthyroid normal subjects and hepatitis C virus infected blood donors as control groups. The low T3 state, well documented in severe nonthyroidal illnesses, was not found in these HIV infected patients. They showed lower FT4 levels and higher TSH and TBG values than euthyroid normal controls. These findings suggested a thyroid hypofunction becoming more evident with the progression of the infection as also supported by the presence of antithyroid autoantibodies mainly found in the symptomatic stages of the infection.

Hydrolysis and association of leucine enkephalin to lymphomic and erythroleukaemic cell lines--II

The relationship between the hydrolysis of labelled leucine enkephalin and the association of its radioactive label to the cells of lymphomic and erythroleukaemic cell lines have been studied using intact cells and resealed membranes obtained from these cells as models. Hydrolysis by cell enzymes and its effect on association have been analysed using protease inhibitors and non-hydrolysable enkephalin analogues. Results obtained confirm that hydrolysis of the pentapeptide is a prerequisite for association of the radiolabel to cells. The same results provide evidence of marked differences between enkephalin hydrolysis by whole cells and hydrolysis measured in the presence of resealed membranes, suggesting the existence in intact cells of proteolytic enzymes other than those bound to the membranes. The lack of reversibility of association and the intracellular localization of the radioactive label suggest that the association measured is prevailingly caused by internalization of a hydrolysis fragment, and not by binding to receptors. In order to determine the nature of the active fragment, association was measured in the presence of all four labelled N-terminal hydrolysis fragments of leu-enkephalin under conditions of nearly-total inhibition of proteolytic enzymes. Under these conditions, the label carried by Tyr, but not that carried by the other N-terminal fragments, was associated with cells. Free Tyr, furthermore, inhibits the association to cells of both labelled Tyr and leu-enkephalin. Data summarized above are consistent with the hypothesis that the radioactive label is taken up by the cells as Tyr, freed from the parent peptide by cell-related enzymes. The same data tend to exclude that a relevant fraction of the intact pentapeptide is bound to membrane receptors or that the radioactive label is carried into the cell by a N-terminal fragment other than Tyr.

[Cervico-vaginal infection by HPV: cyto-histological morphology in the different viral strains]

One-hundred ten cervical or vaginal bioptic samples have been submitted to in-situ HPV typing with biotinylated probes. All samples had been taken from women with colposcopic findings suggesting HPV infection, and at histopathology showed koilocytosis sometimes associated with CIN or VAIN. Sixty-four samples were positive (16 for HPV 6/11 - 37 for HPV 16/18, 11 for HPV 31/35/51). Histopathological and cytological specimens were reviewed to detect the possible existence of morphological patterns typical of the various viral types. Papillomatosis, slightly increased nuclear size with finely granular chromatin, low number of mitoses, and scarce cyto-polymorphism, were associated with HPV 6/11, as well as the absence of intraepithelial neoplasia. A higher number of mitoses (and/or atypical ones), cyto-polymorphism, association with intraepithelial neoplasia, nuclear vacuolization, nuclei of increased size, with irregular borders, hyperchromic, with dark and lumpy chromatin were indicative of high or medium risk HPV (16/18 or 31/35/51). In cytological smears also the finding of dyskeratocytes was associated with these viral types, while multiple nuclei were present in the case of HPV 31/35/51 detection.

Isoelectric focusing and immunoblotting analysis of thyroglobulin from different thyroid diseases

Thyroglobulins (Tgs) have been obtained from macro-microfollicular goiter, toxic adenomas, papillary carcinomas and metastatic lympho-node and chromatographed by gel filtration. The 19S Tgs so obtained have been characterized by isoelectric focusing (IEF) and immunoblotting. IEF showed microheterogeneity pattern of Tgs from normal tissue, macro-microfollicular goiter and toxic adenomas to be within pH range from 4.2 to 4.5, while that from papillary carcinomas and metastatic lympho-node showed a wider microheterogeneity. Passive blotting of focused Tgs and immunoreaction with rabbit anti-Tg peroxidase conjugated antibody have been carried out and a positive reaction for all examined samples have been evidenced. Also two bands, focused at more cathodic pH value (pH 4.7), observed in IEF patterns of Tgs from carcinomas and metastatic lympho-node, gave a positive reaction with anti-Tg conjugated antibody. These differences observed in IEF and immunoblotting patterns of Tgs from papillary carcinomas and metastatic lympho-node are discussed in this report.

Control mechanisms of peripheral enkephalin hydrolysis in mammalian plasma

The protection of the adrenal-released enkephalins from enzyme hydrolysis by endogenous plasma components was studied in laboratory animals and in man. The results indicate that mechanisms active in protecting leu-enkephalin from hydrolysis are present in the plasma of all species examined. The protection seems to be due to two groups of substances, possibly of peptidic nature. The amount of protection given by these substances seems to be sufficient to play a significant role in controlling the physiological levels of leu-enkephalin released into the bloodstream.

[Hutchinson-Horton giant cell arteritis and rhizomelic polymyalgia. III. Current pathogenetic and nosographic aspects]

There is much evidence to suggest that temporal arteritis and rhizomelic polymyalgia are both immunological diseases. The classic results of experimental pathology are discussed, together with the relations between rhizomelic polymyalgia and both virus hepatitis B and the HLA system. From the clinical standpoint, it is now agreed that differences in individual response may lead to either a synovial or an arteritic response in both forms. Their association in what Hamrin has called "polymyalgia arteritica" is also common.

[Hutchinson-Horton giant cell arteritis and rhizomelic polymyalgia. II. Rhizomelic polymyalgia. Arteritic polymyalgia]

Rhizomelic polymyalgia is an inflammatory form. Its site of choice is the shoulder girdle and it is almost solely observed in elderly subjects. An account is given of its epidemiological, clinical and anatomopathological aspects. Its aetiology is also discussed with particular reference to its possible immunological or vascular origin. The rheumatic symptoms of rhizomelic polymyalgia are similar to those observed in temporal arteritis. Since artery lesions are found in most cases, the name "polymyalgia arteritica" has been suggested as an alternative clinical description by Hamrin .

[Hutchinson-Horton giant cell arteritis and rhizomelic polymyalgia. I. Hutchinson-Horton arteritis]

Temporal arteritis (also known as Horton's or giant cell arteritis) is a panarteritis of the large and medium-calibre cranial vessels. An account is given of its epidemiological, clinical and anatomopathological aspects and its involvement of the locomotor apparatus (Horton's rheumatism). Reference is also made to the close relationship between temporal arteritis and pulseless disease. Some workers are of the opinion that they share the same aetiology, and that their clinical expression in different areas is dictated by age and constitutional factors.

Serial blood T4 and TSH determinations in low birth weight infants. Influence of gestational age, birth weight and neonatal pathology on thyroid function

Serial blood T4 and TSH determinations were performed on a total number of 352 low birth weight (LBW) infants: 210 healthy newborns and 142 infants affected by respiratory distress syndrome (RDS), sepsis, hyperbilirubinaemia, hypocalcemia, or hypoglycemia. The healthy infants have been divided into three groups in relation to gestational age (less than or equal to 33 wk, 34-36 wk, greater than or equal to 37 wk). Statistical evaluation among groups shows that reduced T4 concentration in LBW infants is strictly related to gestational age, while TSH failed to demonstrate any significant correlation. No significant influence of birth weight on T4 and TSH has been observed. The preterm newborns affected by RDS or sepsis showed a significant reduction of mean T4 concentrations up to 20th day of life when compared with healthy controls similar for gestational age and birth weight. TSH levels are not significantly different. No significant modifications of T4 and TSH have been found related to the other pathological conditions. The significant reduction of T4 and the high incidence of subjects with low T4 values observed in healthy and sick preterm population lend further support to the use of TSH determination for optimum screening of congenital hypothyroidism.

Familial thyroxine-binding globulin deficiency detected in a pilot screening program for congenital hypothyroidism

During a pilot screening program for congenital hypothyroidism, performed in Italy over a three years period on 38,000 newborns, seven cases (1/5,400) of thyroxine-binding globulin (TBG) deficiency, have been detected. None of these infants was affected by any pathology or had been treated with drugs which could explain TBG deficiency as an acquired condition. Familial studies pointed out that the transmission of the defect is consistent or compatible with X-chromosome linkage.

[Amyloidosis. II. Current pathogenetic and clinico-nosographic aspects]

Amyloidosis is due to the overproduction of a precursor protein and its conversion into products capable of polymerisation into fibrils. The primary form, or that associated with multiple myeloma or Waldenström's macroglobulinaemia, marked by the presence of protein AL, includes the overproduction of Ig light chains followed by conversion on the part of lysosome enzymes. The forms can thus be classified as immunoproliferative diseases (plasma-cell dyscrasias). Secondary amyloidosis is primarily associated with neoplasia or chronic inflammation. Its biochemical label is the AA protein. Initially, there is overproduction of protein SAA, while the formation of AA-amyloid fibrils may theoretically be attributed to a variety of factors: changes in the amount of circulating SAA, the presence of amyloidogenetic SAA, variations in the activity of SAA catabolic systems, insufficient removal of acculated fibrils. The way in which the immunocompetent system intervenes is a controversial subject. Lesser froms of amyloidosis are known in which there are local deposits of amyloid: APUD-amyloidosis, amyloidomas. In some forms, the features of systemic accumulation are maintained, but only one organ is primarily involved. They are rarely of clinical significance (e.g. senile amyloidosis). Current biochemical techniques enable a clinical and nosographic distinction to be drawn between an Ig (AL)-amyloidosis and non-Ig (AA, APUD and AS) forms.

[Amyloidosis. I. Recent findings concerning amyloid substance]

The considerable progress made recently in the study of amyloid substance have led to the identification of numerous organised protein components in typical microfibrillar structures. In spite of the biochemical heterogeneity of fibril proteins, it is still possible to find similar chemicophysical and tintorial features in the various types of amyloid, probably due, at least in part, to the common Beta type molecular configuration, a structure proper to fibril proteins. In so-called primary amyloidosis and in that associated with myelomatous diseases, the principal protein component consists of AL protein, correlated with the light immunoglobulin chains, with which analogies have been observed both in the amino acid sequence and in antigenic characteristics. In secondary amyloidosis, AA protein, which is unrelated to immunoglobulins or other known human proteins, is prevalent. AA protein probably derives from a serum globulin, SAA, whose blood levels increase during numerous pathological processes, particularly in those of neoplastic or inflammatory type. The origin of serum protein, which might be either a normal tissue component released under stimulus or a reagent of the acute phase synthesised ex novo, and its function, which is probably of immunomodulator or more specifically immunosuppressive type, are still to be defined. In all forms of amyloidosis studied, a common observation is the presence of AP protein, organised in pentagonal structures. This protein would appear to derive from a serum component defined as SAP, with a marked affinity for amyloid fibrils. Also identifiable are other forms of amyloid such as APUD-amyloid, which probably derives from polypeptide hormones, and AS amyloid, which is present in some organs of elderly patients and is biochemically identifiable at cardiac level with A(SCA) protein. Still awaiting definition in amyloid tumours or amyloidomas is the precise chemical composition of deposited proteins.