Trapping an unprecedented octacoordinated iron(II) complex with neutral bis-tetrazolylpyridyl ligands and solvent molecules

Iron(II) can show a very rich coordination chemistry with concomitant modulation of its properties as promising functional materials. Metalation of the neutral tridentate nitrogen-donor mer-coordinating ligand 2,6-bis(2-(methyl)-2H-tetrazol-5-yl)pyridine (Me2btp) with Fe(ClO4)2·6H2O through accurate solvent polarity control enables the selective crystallization of [FeHS/LS(Me2btp)2](ClO4)2·MeCN·2.75H2O (2HS/LS·MeCN·2.75H2O) as red rods, where half of the iron(II) centres resides in the low spin (LS, S = 0) state and the other half is in the high spin (HS, S = 2) state. The red rods spontaneously convert into yellow crystals once removed from the mother liquor and exposed to air due to solvent rearrangement within the crystal packing; these new crystals can be assigned to [FeHS(Me2btp)2](ClO4)2·solvent (2HS·solvent) where all the iron(II) centres are now blocked in the HS state, as confirmed by magnetic measurements. The polarity of the crystallization solvent, together with the maintenance of the crystals within the mother liquor, are pivotal for the reactivity and interconversion of different species. Indeed, upon long standing in solution, 2HS/LS·MeCN·2.75H2O converts to another form of red crystals belonging to [FeLS(Me2btp)2][FeHS(Me2btp)(MeCN)2(H2O)](ClO4)4·MeCN (2LS·3HS·MeCN), as confirmed by single crystal X-ray diffraction data. In this co-crystal, the iron(II) in 2 resides in the LS state at all temperatures while the iron(II) in 3 is blocked in the HS state. Well-formed yellow crystals could be also isolated among the red crystals of 2HS/LS·MeCN·2.75H2O, and they could be identified as the unprecedented octacoordinated species [Fe(Me2btp)2(MeCN)(H2O)](ClO4)2·H2O (1·H2O) by single-crystal X-ray diffraction. These yellow crystals are stable in the air, but slowly convert into 2LS·3HS·MeCN if kept in the mother liquor for about one week. 1·H2O can be considered the trapped intermediate in the solid state during the conversion of [FeHS(Me2btp)2]2+ into [FeHS(Me2btp)(MeCN)2(H2O)]2+ in solution, where the two tridentate ligands in the starting species can unfold to accommodate coordinated MeCN and H2O molecules, as confirmed by theoretical calculations, and eventually one of the two Me2btp is completely replaced by the solvent.

River widening in mountain and foothill areas during floods: Insights from a meta-analysis of 51 European Rivers

River widening, defined as a lateral expansion of the channel, is a critical process that maintains fluvial ecosystems and is part of the regular functioning of rivers. However, in areas with high population density, channel widening can cause damage during floods. Therefore, for effective flood risk management it is essential to identify river reaches where abrupt channel widening may occur. Despite numerous efforts to predict channel widening, most studies have been limited to single rivers and single flood events, which may not be representative of other conditions. Moreover, a multi-catchment scale approach that covers various settings and flood magnitudes has been lacking. In this study, we fill this gap by compiling a large database comprising 1564 river reaches in several mountain regions in Europe affected by floods of varying magnitudes in the last six decades. By applying a meta-analysis, we aimed to identify the types of floods responsible for more extensive widening, the river reach types where intense widening is more likely to occur, and the hydraulic and morphological variables that explain widening and can aid in predicting widening. Our analysis revealed seven groups of reaches with significantly different responses to floods regarding width ratios (i.e., the ratio between channel width after and before a flood). Among these groups, the river reaches located in the Mediterranean region and affected by extreme floods triggered by short and intense precipitation events showed significantly larger widening than other river reaches in other regions. Additionally, the meta-analysis confirmed valley confinement as a critical morphological variable that controls channel widening but showed that it is not the only controlling factor. We proposed new statistical models to identify river reaches prone to widening, estimate potential channel width after a flood, and compute upper bound width ratios. These findings can inform flood hazard evaluations and the design of mitigation measures.

A proficient multivariate approach for iron(II) spin crossover behaviour modelling in the solid state

Iron(II) bis-pyrazolilpyridyl (bpp-R) complexes [Fe(bpp-R)₂](X)₂·solvent, R = substituent and X^- = anion, can undergo a spin transition from high (S = 2, HS) to low spin (S = 0, LS), being spin crossover (SCO) in the solid state. The distortion of the octahedral coordination environment around the metal centre is governed by crystal packing, i.e. the intermolecular interactions among the substituent R of the bpp-R ligands, the anion X^-, and the co-crystallized solvent, and this modulates the SCO behaviour. In this work, an innovative multivariate approach, through the combination of the chemometric tools Principal Component Analysis and Partial Least Squares regression, was applied on the coordination bond distances and angles and selected torsional angles of the available HS structures. The obtained results can efficiently model and rationalize the structural data distinguishing between SCO-active and HS-blocked complexes bearing different R groups, X^- anions, and co-crystallized solvents and help predict the spin transition temperature T_1/2.

Substituent-Guided Cluster Nuclearity for Tetranuclear Iron(III) Compounds with Flat {Fe4(μ3-O)2} Butterfly Core

The tetranuclear iron(III) compounds [Fe4(μ3-O)2(μ-LZ)4] (1–3) were obtained by reaction of FeCl3 with the shortened salen-type N2O2 tetradentate Schiff bases N,N’-bis(salicylidene)-o-Z-phenylmethanediamine H2LZ (Z = NO2, Cl and OMe, respectively), where the one-carbon bridge between the two iminic nitrogen donor atoms guide preferentially to the formation of oligonuclear species, and the ortho position of the substituent Z on the central phenyl ring selectively drives towards Fe4 bis-oxido clusters. All compounds show a flat almost-symmetric butterfly-like conformation of the {Fe4(μ3-O)2} core, surrounded by the four Schiff base ligands, as depicted by both the X-ray molecular structures of 1 and 2 and the optimized geometries of all derivatives as obtained by UM06/6-311G(d) DFT calculations. The strength of the antiferromagnetic exchange coupling constants between the iron(III) ions varies among the three derivatives, despite their magnetic cores remain structurally almost unvaried, as well as the coordination of the metal ions, with a distorted octahedral environment for the two-body iron ions, Feb, and a pentacoordination with trigonal bipyramidal geometry for the two-wing iron ions, Few. The different magnetic behavior within the series of examined compounds may be ascribed to the influence of the electronic features of Z on the electron density distribution (EDD) of the central {Fe4(μ3-O)2} core, substantiated by a Quantum Theory of Atoms In Molecules (QTAIM) topological analysis of the EDD, as obtained by UM06 calculations 1–3.

Ovarian tissue cryopreservation and transplantation in menopause: new perspective of therapy in postmenopausal women and the importance of ethical and legal frameworks

Menopausal transition entails a progressive decrease in hormone production by the ovaries that lead to important physical and psychological changes that could significantly affect quality of life. Hormone replacement therapy (HRT) administered from the onset of menopausal symptoms usually improves quality of life and life expectancy. Nevertheless, it is not risk-free. Ovarian tissue cryopreservation (OTC) has been investigated as a potential new strategy for delaying menopause and/or to avoid HRT. This review analyzes the critical points of HRT to assess whether OTC and subsequent reimplantation can affect postmenopausal management. We assessed available randomized clinical trials in PubMed, Cochrane Library, ISI web of science, and Scopus from August 2021 to November 2022, including studies and trials evaluating the efficacy of OTC in both cancer and menopausal patients, the efficacy of freezing techniques and the possible clinical scenarios that OTC can open, even from the standpoint of legal and ethical issues arising as such innovative techniques become mainstream. Lower duration of the graft and efficacy on estrogen secretions at a physiological and safer concentration of estrogen than conventional HRT based on hormonal supplements. OTC can reportedly trigger estrogen secretions at a lower and safer physiological concentration than conventional HRT. OTC and subsequent reimplantation remain a valid fertility-sparing approach in patients undergoing gonadotoxic treatments. Further studies are needed to better evaluate its safety and efficacy within postmenopausal therapy management and in order to lay out widely shared and evidence-based guidelines and best practices and perform such novel and innovative techniques in a legally and ethically safe fashion, in the best interest of patients and healthcare professionals.

How to easily detect plant NADH-glutamate dehydrogenase (GDH) activity? A simple and reliable in planta procedure suitable for tissues, extracts and heterologous microbial systems

Plant NADH glutamate dehydrogenase (GDH) is an intriguing enzyme, since it is involved in different metabolic processes owing to its reversible (anabolic/catabolic) activity and due to the oligomeric nature of the enzyme, that gives rise to several isoforms. The complexity of GDH isoenzymes pattern and the variability of the spatial and temporal localization of the different isoforms have limited our comprehension of the physiological role of GDH in plants. Genetics, immunological, and biochemical approaches have been used until now in order to shed light on the regulatory mechanism that control GDH expression in different plant systems and environmental conditions. We describe here the validation of a simple in planta GDH activity staining procedure, providing evidence that it might be used, with different purposes, to determine GDH expression in plant organs, tissues, extracts and also heterologous systems.

Survey of the vaia storm deposits in the tegnas catchment (Dolomites, Italy): Field data and evidence of sediment-water flow types

Brenna et al. [1] developed a survey protocol to collect evidence aimed at classifying flood deposits on the basis of the flow type that mobilized and deposited sediment. Such a survey protocol was adopted to characterize the flood deposits in a mountain catchment of the Dolomites (the Tegnas Torrent and its tributaries; drainage area of 51 km²) after a high-magnitude hydrological event that occurred in October 2018 (the so-called “Vaia Storm”). In this article, we present the field data collected at thirty-two survey sites considering the geomorphological and sedimentological characteristics of the analysed sedimentary products and their effects on the vegetation. Data on the characteristics of the flood deposits have enabled recognizing the transport mechanisms that occurred during the Vaia Storm along the stream network [1]. Future applications of the survey protocol adopted in this study could compare and integrate the collected data with those presented in detail in this article.

Alpha-1 antitrypsin deficiency is significantly associated with atopy in asthmatic patients

BACKGROUND

Although the etiology and disease mechanisms of asthma and alpha-1 antitrypsin deficiency (AATD) are distinct, several reports indicate that asthma is common in AATD patients, however the relationships between asthma and AATD are poorly described in the literature.

OBJECTIVES

The aim of the study was to investigate in a cohort of outpatients affected by mild to moderate asthma the clinical features that may differentiate asthmatic patients with and without mutation on SERPINA1 gene.

METHODS

Seven hundred thirty-five asthmatic outpatients underwent quantitative analysis of the serum level of alpha-1antitrypsin. According to the literature only sixty-seven out of seven hundred thirty-five asthmatic patients were submitted to genetic analysis to identify AATD and non-AATD subjects. Fifty-eight patients were studied. Clinical and functional data, including lung function, atopy and bronchial hyperactivity, were recorded.

RESULTS

The fifty-eight asthmatic patients were divided in AATD patients (n = 22) and non AATD patients (n = 36), according to genotype. The presence of atopy was significantly higher in patients with AATD than in those without AATD (91% vs. 64%; p = 0.031). AATD patients reported allergic manifestations more than non AATD patients (77% vs. 47%; p = 0.030).

CONCLUSION

Our study shows that the presence of atopy in asthmatic patients with AATD is significantly higher than in asthmatic patients without gene mutation. In addition, a higher percentage of AATD patients self-reported allergic manifestations. No significant differences in respiratory symptoms, physical examination, disease severity or inflammation markers were found between AATD patients and non AATD patients.

Channel control works and sediment connectivity in the European Alps

The need for reducing erosion and sediment transport, and protecting human settlements has urged the construction of channel control works in mountain streams. Such works include different structures, the check dams being probably the most widespread and archetypical. The performance of channel control works in mountain streams has usually been evaluated based on their effectiveness in stabilizing the channels and the adjacent hillslopes, and in retaining sediment. The widespread presence of channel control works in mountain streams of various regions, however, has also a significant impact on hillslope-channel coupling and on sediment transfer across the channel system. Taking into account the impact of channel control works on sediment connectivity at the catchment scale has remarkable importance for planning new control structures and managing the existing ones and, more in general, for sediment management in mountain catchments. In this paper, we consider the channel control works within the conceptual framework of sediment connectivity and related terminology, and we analyze the spatial and temporal scales of the interactions between channel control works and sediment coupling-decoupling. Some examples from the Italian Alps outline the impact of check dams and other hydraulic structures on sediment connectivity and show the potential of geomorphometry in assessing such impacts. The overall effect of control works on sediment connectivity consists of an alteration of the sediment cascade with a decrease in the efficiency of sediment transfer. Sediment is partly retained behind grade-control dams within the catchment or in sediment traps equipped with retention check dams near the alluvial fan apex. These works contribute to decouple the alluvial fans from the upslope catchment. On the contrary, channel bed lining on alluvial fans favors sediment transfer to the receiving river, but this effect usually involves small amounts of sediment not retained by the check dams built upstream.

Basin-scale analysis of the geomorphic effectiveness of flash floods: A study in the northern Apennines (Italy)

Large floods may produce remarkable channel changes, which determine damages and casualties in inhabited areas. However, our knowledge of such processes remains poor, as is our capability to predict them. This study analyses the geomorphic response of the Nure River (northern Italy) and nine tributaries to a high-magnitude flood that occurred in September 2015. The adopted multi-disciplinary approach encompassed: (i) hydrological and hydraulic analysis; (ii) analysis of sediment delivery to the stream network by means of landslides mapping; (iii) assessment of morphological modifications of the channels, including both channel width and bed elevation changes. The spatial distribution of rainfall showed that the largest rainfall amounts occur in the upper portions of the catchment, with cumulative rainfall reaching 300 mm in 12 h, and recurrence intervals exceeding 100-150 years. The unit peak discharge ranged between 5.2 and 25 m³ s^-1 km^-2. Channel widening was the most evident effect. In the tributaries, the ratio between post-flood and pre-flood channel width averaged 3.3, with a maximum approaching 20. Widening was associated with channel aggradation up to 1.5 m and removal of riparian vegetation. New islands formed due to the fragmentation of the former floodplain. In the Nure River, the average width ratio was 1.7, and here widening occurred mainly at the expenses of islands. Bed level dynamics in the Nure were varied, including aggradation, incision, and overall stability. The flood geomorphic effectiveness was more pronounced in the middle-higher portions of the basin. Planimetric and elevation changes were well correlated. Regression analysis of the relationship between widening and morphological/ hydraulic controlling factors indicated that unit stream power and confinement index were the most relevant variables. The study provides useful insights for river management, especially with regard to the proportion of the valley floor subject to erosion and/or deposition during large events.

Experimental Vitreous Replacement with Perfluorophenanthrene

PURPOSE

We studied the toxicity of perfluorophenanthrene (PFP), used as short-, medium-, or long-term internal tamponading substance, on the rabbit choroid and retina. The aim was the check whether PFP is tolerated as a tamponade in the eye or damages the retina, and if any such damage is due to toxicity or to emulsification which may stimulate phagocytosis.

METHODS

Twenty-four right eyes of rabbits operated by vitrectomy were filled with 0.8-1 ml of PFP as retinal tamponading substance. Twelve eyes were operated by vitrectomy and filled with 0.8-1 ml of balanced salt solution as the control group. Direct and indirect ophthalmoscopy was done on the third and seventh day after surgery, then once a week. Enucleation, with histological and immunohistochemical examination, was done on the second day, then in the first, second, fourth and eighth weeks after surgery.

RESULTS AND CONCLUSIONS

Histological examination showed progressive damage of the chorioretinal tissues right from the second week: the chorioretinal structure was completely altered from the eighth week. Immunohistochemical examinations showed that glia cells were involved in the inflammation consequent to internal tamponade with PFP.

Systems and Sensors for Debris-flow Monitoring and Warning

Debris flows are a type of mass movement that occurs in mountain torrents. They consist of a high concentration of solid material in water that flows as a wave with a steep front. Debris flows can be considered a phenomenon intermediate between landslides and water floods. They are amongst the most hazardous natural processes in mountainous regions and may occur under different climatic conditions. Their destructiveness is due to different factors: their capability of transporting and depositing huge amounts of solid materials, which may also reach large sizes (boulders of several cubic meters are commonly transported by debris flows), their steep fronts, which may reach several meters of height and also their high velocities. The implementation of both structural and non-structural control measures is often required when debris flows endanger routes, urban areas and other infrastructures. Sensor networks for debris-flow monitoring and warning play an important role amongst non-structural measures intended to reduce debris-flow risk. In particular, debris flow warning systems can be subdivided into two main classes: advance warning and event warning systems. These two classes employ different types of sensors. Advance warning systems are based on monitoring causative hydrometeorological processes (typically rainfall) and aim to issue a warning before a possible debris flow is triggered. Event warning systems are based on detecting debris flows when these processes are in progress. They have a much smaller lead time than advance warning ones but are also less prone to false alarms. Advance warning for debris flows employs sensors and techniques typical of meteorology and hydrology, including measuring rainfall by means of rain gauges and weather radar and monitoring water discharge in headwater streams. Event warning systems use different types of sensors, encompassing ultrasonic or radar gauges, ground vibration sensors, videocameras, avalanche pendulums, photocells, trip wires etc. Event warning systems for debris flows have a strong linkage with debris-flow monitoring that is carried out for research purposes: the same sensors are often used for both monitoring and warning, although warning systems have higher requirements of robustness than monitoring systems. The paper presents a description of the sensors employed for debris-flow monitoring and event warning systems, with attention given to advantages and drawbacks of different types of sensors.

Procedures for the documentation of historical debris flows: application to the Chieppena Torrent (Italian alps)

The reconstruction of triggering conditions, geomorphic effects, and damage produced by historical floods and debris flows significantly contributes to hazard assessment, allowing improved risk mitigation measures to be defined. Methods for the analysis of historical floods and debris flows vary greatly according to the type and quality of available data, which in turn are influenced by the time the events occurred. For floods and debris flows occurring in the Alps a few decades ago (between about 1950 and 1980), the documentation is usually better than for previous periods but, unlike events of most recent years, quantitative data are usually scanty and the description of the events does not aim to identify processes according to current terminology and classifications. The potential, and also the limitations of historical information available for the reconstruction of historical debris flows in the Alps have been explored by analyzing a high-magnitude debris flow that occurred on November 4, 1966 in the Chieppena Torrent (northeastern Italy). Reconstruction of the event was based on the use of written documentation, terrestrial and aerial photographs, and geomorphological maps. The analysis aimed to define the temporal development of phenomena, recognizing the type of flow processes and assessing some basic flow variables, such as volume, channel-debris yield rate, erosion depth, total distance traveled, and runout distance on the alluvial fan. The historical development of torrent hydraulic works, both before and after the debris flow of November 1966, was also analyzed with regard to the technical solutions adopted and their performance.

First isolation and characterization in humans of Entamoeba histolytica (laboratory-made) zymodeme XX

Isoenzyme analysis by starch-gel electrophoresis has proved to be a useful method for the biochemical differentiation of pathogenic Entamoeba histolytica and non-pathogenic E. dispar isolates. Of the known 24 zymodemes, 3 are laboratory-made and have not previously been identified in humans. Parasitology screening was carried out in a psychiatric institution. Two amebic stocks were isolated and characterized that had never previously been found in humans and that have protein patterns identical to that of the laboratory-made zymodeme XX.

Synthesis and secretion of B-100 and A-I apolipoproteins in response to the changes of intracellular cholesteryl ester content in chick liver

We investigated in the chick whether the diet-induced changes of the hepatic content of cholesteryl esters (CE) influence the synthesis and the secretion of apoB- and apoA-I-containing lipoproteins. Control chicks received a low cholesterol diet for 2 (SD-1), 4 (SD-2), or 7 (SD-3) weeks; the chicks in the experimental groups received a cholesterol-rich diet for 2 weeks and were killed at the end of the cholesterol feeding (CH-F), and after 2 (CH-D) or 5 (CH-DD) weeks of a low cholesterol diet. Hepatic CE content in CH-F chicks was 30-fold that observed in controls, but returned to the control level after 5 weeks of cholesterol depletion (CH-DD). The incorporation of 35S-labeled amino acids into cell and medium apoB and apoA-I was measured in liver slices. Intracellular 35S-labeled apoB was similar in all groups whereas medium 35S-labeled apoB was 2-fold higher in CH-F than in controls (SD-1). Pulse-chase experiments showed that radioactive apoB secreted by CH-F chicks at 120 min of chase was 2 times that of SD-1 chicks. This increased secretion of apoB was not found in CH-D chicks. In CH-F chicks, the intracellular and medium 35S-labeled apoA-I were 2-fold the values found in controls (SD-1); apoA-I production returned to the control level only after 5 weeks of cholesterol depletion (CH-DD). The increased secretion of apoB and apoA-I in CH-F chicks was associated with an increased secretion of very low, intermediate, and low density lipoproteins containing newly synthesized apoB and apoA-I and of high density lipoproteins containing predominantly apoA-I. Thus, in response to hepatic CE accumulation induced by cholesterol feeding, a larger proportion of newly synthesized apoB is driven to the secretory pathway and more apoA-I is synthesized. This promotes an increased secretion of plasma lipoproteins that contribute to the removal of CE from the liver.

Benign recurrent intrahepatic cholestasis. Some reflections on a case followed for 20 years

Benign recurrent intrahepatic cholestasis (BRIC) is a form of cholestasis of obscure aetiology characterized by recurrent episodes of jaundice and itching associated with a morphological picture of pure intrahepatic cholestasis. No effective treatment has yet been found among the many that have been proposed and the invariably benign nature of the condition has been questioned. A case of BRIC followed for a period of 20 years is described. This case is of great interest from these two points of view: 1) the histologic and electron microscopic findings 23 and 41 years after the first episode of cholestasis, respectively, failed to reveal evidence of the possible future development of cirrhosis; 2) treatment with ursodeoxycholic acid proved ineffective both therapeutically and in the prevention of episodes of bile stasis: on the contrary, calculosis of the common bile duct appeared after 8 months from the onset of the treatment.

Ultrasound in the diagnosis of gallbladder ascariasis

Ascariasis is the most common helminthic infection, but the invasion of worms into the gallbladder is quite rare. This report illustrates the ultrasonographic findings in gallbladder ascariasis of a typical echogenic structure which exhibits nondirectional movements and contains a central anechoic tube, along the long axis of the gallbladder. The role of ultrasound as a diagnostic tool and in the follow-up treatment is stressed.

Entamoeba histolytica autochthonous isolates from mentally retarded Italian patients

A total of 77 mentally retarded male inpatients residing in a psychiatric institution in northern Italy were screened for the presence of stool parasites, Entamoeba histolytica particularly. Parasitological stool examination showed Entamoeba spp. (E. histolytica and/or E. dispar) in 26 cases (33.7%). In vitro culture on Robinson's medium was positive in 16 cases (61.1%); in 11 cases we could stabilize and clone the isolates and proceed to electrophoretic assays. In all cases, patterns of pathogenic zymodemes were found (zymodeme II, 3 isolates; zymodeme XII, 4 isolates; zymodeme XIV, 4 isolates). All isolates were therefore identified as E. histolytica.

Apolipoprotein B-100 production and cholesteryl ester content in the liver of developing chick

In the chick, the large cholesteryl ester (CE) store present in the liver during the last period of embryonic life increases at hatching and is rapidly depleted after 2-7 days of postnatal life. In this study we asked whether these changes were associated with variations in the hepatic production of apoB-containing lipoproteins. Liver slices taken from chicks at -3, 0 (hatching), 2, 4, 7, and 10 days of development were incubated with [35S]methionine in steady state incubations. ApoB production (cell + medium radioactivity) decreased from day -3 to day 0 (40%), increased at day 4 (54%), and decreased afterwards (45%). At day 4 the amount of 35S-labeled apoB-containing lipoproteins (VLDL-LDL) secreted into the medium was 1.7- and 1.5-times that found at days 0 and 7, respectively; the radioactivity incorporated into medium HDL (containing predominantly apoA-I) was 1.7-times that found at days 0 and 7. The incubation of liver slices with [3H]oleate showed that CE production at days 4 and 7 was 58% and 33%, respectively, of that found at day 0. The percentage of newly synthesized hepatic CE secreted into medium lipoproteins was 2.4%, 3.1%, and 2.2% at days 0, 4, and 7, respectively. The percentage of lipoprotein CE present in VLDL-LDL ranged from 38% at day 0 to 21% at day 7, and that present in HDL ranged from 62% at day 0 to 79% at day 7. To define whether the changes in the production of apoA-I- and apoB-containing lipoproteins were due to variations in apoB and apoA-I synthesis, the initial synthetic rate (pulse-labeling) and the mRNA content of these apolipoproteins were investigated. The initial apoB synthetic rate decreased 1.5-fold from day -3 to day 0, remained stable up to day 7, and decreased at day 10. Hepatic apoB mRNA followed a similar trend. The synthesis of apoA-I increased 2-fold from days -3/2 up to day 4 and did not change afterwards. In conclusion the increased hepatic CE content at hatching reflects a decreased production of apoB, while the depletion of CE observed from day 2 to day 7 is associated with an increased production of both apoB- and apoA-I-containing lipoproteins. The decreased apoB production at hatching is due to a decreased apoB synthesis whereas the increased apoB production at day 4 appears to be related to a post-translational event.

The effect of a thromboxane A2 synthase inhibitor on the dyslipoproteinemia of an inbred rat strain with spontaneous age-related nephrotic syndrome

We have previously shown that the administration of a thromboxane A2 (TXA2) synthase inhibitor (FCE 22178) reduced the progression of glomerular lesions and proteinuria in MNS rats, an inbred strain which develops an age-related nephrotic syndrome. In the present study we investigated the effect of FCE 22178 on the plasma lipoproteins of MNS rats at 28 weeks of age (with mild proteinuria and moderate dyslipoproteinemia) and at 48 weeks of age (with heavy proteinuria and severe dyslipoproteinemia). Drug treatment reduced proteinuria (by 70% and 36% at 28 and 48 weeks of age, respectively) plasma cholesterol (by 36% and 27% at 28 and 48 weeks of age, respectively) and prevented the decrease of plasma albumin observed in untreated rats (C-MNS) 48 weeks old. In treated rats (T-MNS), the decrease of proteinuria was positively correlated with that of plasma cholesterol. FCE 22178 reduced the elevation in plasma HDL1 (by 17.4%) and HDL2 levels (by 30%), a key feature of nephrotic dyslipoproteinemia in the rat. From 28 to 48 weeks of age plasma apo A-I and apo E increased 217% and 128%, respectively, in C-MNS rats and 191% and 121%, respectively, in T-MNS rats. A significant increase of apo A-I/apo E ratio was found in C-MNS rats from 28 (2.28 +/- 0.36) to 48 weeks of age (3.84 +/- 0.9) but not in T-MNS rats. FCE 22178 altered the lipid composition of VLDL and HDL2 by reducing the content of cholesteryl esters and increasing that of free cholesterol and phospholipids. These findings suggest that the beneficial effect of FCE 22178 on the dyslipoproteinemia of nephrotic MNS rats is secondary to the amelioration in kidney function and to the reduction of proteinuria produced by this drug.

Autochthonous amoebiasis in institutionalized mentally-retarded patients: preliminary evaluation of isoenzyme patterns in three isolates

Three autochthonous cases of Entamoeba histolytica infection in institutionalized mentally-retarded patients are reported. Isoenzyme analysis by starch-gel electrophoresis shows the pathogenicity of the three isolates: two belong to zymodeme II, and one to zymodeme XIX. The study shows that invasive E. histolytica strains occur in Italy and can be isolated from institutionalized oligophrenic patients.

Benign recurrent intrahepatic cholestasis. A clinico-pathologic study

Authors report 6 cases of benign recurrent intrahepatic cholestasis (BRIC), a rare disease of unknown etiology first described 30 years ago by Summerskill and Walshe, and thought to represent a study model for human cholestasis. Clinical, biochemical and pathologic findings of BRIC are briefly summarized in this paper in order to emphasize some triggering factors of the cholestatic attack (e.g., flu-like episodes and pregnancy), the diagnostic problems and the importance to avoid a surgical procedure. Finally, the 'state of the art' of the pathogenesis of BRIC is briefly summarized.

[Angioimmunoblastic lymphadenopathy with dysproteinemia]

Angioimmunoblastic lymphadenopathy with dysproteinemia. Angioimmunoblastic lymphadenopathy with dysproteinemia is a lymphomatous-like disease associated with typical anatomopathological features of the lymph nodes and severe dysproteinemia. The clinical course is variable. Acquired immunodeficiency, oral infections, neoplastic development are frequently present. The evolution of the disease is also variable; spontaneous resolution as well as lethal complications are possible. No specific therapy is available. There are conflicting opinions about the nosographic statement of angioimmunoblastic lymphadenopathy among benign lymphadenopathy and lymphomas.

[Angioimmunoblastic lymphadenopathy with dysproteinemia. Personal case reports]

Angioimmunoblastic lymphadenopathy with dysproteinemia. Case report. We report nine cases of angioimmunoblastic lymphadenopathy with dysproteinemia. Initial symptoms were not specific in any case nor was a specific drug involved as a possible cause. In every case we observed a diffuse enlargement of the lymph nodes and severe dysproteinemia (with hyper or hypo-gammaglobulinemia). Death during the first year was observed for four patients.

[Fibrodysplasia ossificans progressiva or Münchmeyer's disease. Personal observation]

We report here a case of fibrodysplasia ossificans progressiva in a 14-year-old boy, affected from birth by microdactyly of the big toes. This skeletal abnormality also existed in his paternal great-grandfather. When he was 7, some ectopic ossifications occurred and inexorably progressed despite all therapies. Fibrodysplasia ossificans progressiva is a serious and rare disease with a terrible development, leading to a sort of petrifaction of the patient. The lack of knowledge on this ectopic ossification process explains the want of suitable treatments to stop the course of this disease.

[Fibrodysplasia ossificans progressiva or Münchmeyer's disease]

Fibrodysplasia ossificans progressiva is a heritable and generalized disorder of connective tissue, characterized by the appearance of bony tissue within the striated muscles, tendons and ligaments; moreover, some skeletal abnormalities may also occur, mainly microdactyly of the big toes. This is a very rare disease, which presents in early life; its course is unavoidably progressive, producing a sort of petrifaction of the patient some years after the first symptoms. It is defined as an autosomal dominant trait, being due in most cases to a new mutation. At present no known treatment is available to stop the course of the disease, but sometimes disodium etidronate may be effective in preventing calcification of heterotopic bony tissue.

[Hypersensitivity angiitis or microscopic polyarteritis nodosa. Recent findings. III. Pathologic anatomy, etiopathogenetic aspects and therapeutic approach]

Histologically hypersensitivity angiitis produces necrotising inflammation of the small arterial and venous blood vessels. In most cases the inflammatory infiltrate presents leucocytoclasia i.e. nuclear leucocytic detritus. Unlike polyarteritis nodosa, hypersensitivity angiitis does not affect the medium sized arteries though its lesions are produced at the same stage of development. At skin level, the postcapillary venules are the vessels most often affected. Fibrinoid necrosis of the glomerular loops of the kidney may arise and is often accompanied by epithelial crescents. Aetiologically, a variety of agents--bacteria, viruses, drugs, toxic substances--have been held responsible for the disease, though very often the cause cannot be identified. The most widely based on the finding of immunocomplexes, though other immunological disorders might be involved. Treatment involves the elimination of the antigen held responsible, the suppression of the immune response, the removal of circulating immunocomplexes and the use of anti-inflammatory drugs.

[Hypersensitivity angiitis or microscopic polyarteritis nodosa. Recent findings. II. Clinical aspects]

Hypersensitivity angiitis is one of the commonest necrotising vasculitides. Given the ubiquitous distribution of the small blood vessels almost any part of the body may be affected. However benign forms predominantly involving the skin are the most common. Forms predominantly involving the viscera and that may prove fatal are rare. Among the polymorphous skin lesions encountered "palpable purpura" is the most common and its palpability is a vital element in differential diagnosis. Among non-cutaneous sites the kidneys are the most frequent and glomerular involvement is the commonest cause of death. Though laboratory tests provide no specific data they may indicate the severity of visceral involvement.

[Angiitis caused by hypersensitivity or microscopic polyarteritis nodosa. Recent findings. I. Nosographic aspects]

Hypersensitivity angiitis or microscopic polyarteritis nodosa is one of the necrotising angiitis and was not distinguished from classic polyarteritis nodosa until the Fifties. The present study examines the nosographic aspects of necrotising angiitides with reference to the anatomohistological, aetiopathogenic and clinical criteria proposed by various Authors for their identification and with emphasis on the fact that all these factors must be borne in mind for the purpose of diagnosis. The factors that make it possible to distinguish hypersensitivity angiitis from other necrotising angiitides are, at clinical level, the presence of skin lesions, and in anatomohistological terms the involvement of the small blood vessels and leucocytoclasia.

[Rubber-band ligation of hemorrhoids]

In the last few years there has been a considerable reduction in surgical treatment of piles; on the other hand a series of therapeutic outpatient treatments has developed aiming at a conservative management of piles. This new approach is mainly due to high costs in surgical treatment. In accordance also with the experience of the most important proctologic centres, nowadays only 26% of our patients suffering from piles undergo operation, since we regard rubber band ligation as a more rational and economical method for the treatment of hemorrhoids. The instruments and the technique related to band ligation have been described together with some modifications suggested by our personal experience. Indications and contraindications for rubber band ligation have been analyzed pointing out that, in our opinion, such an approach is advised also in the management of stage 3 and 4 hemorrhoids; on the other hand the surgical treatment has its role when band ligation is contraindicated. We have then reported about the good results obtained with 162 patients suffering from stage 2, 3 and 4 hemorrhoids, by using band ligation. Our experience, in accordance with international literature, enables us to emphasize the almost complete absence of complications and the satisfactory results of band ligation, even if compared to other methods.

[Blood hypereosinophilias. IV. Symptomatic hypereosinophilias: connective tissue diseases, neoplasms, blood diseases, various causes]

Among the symptomatic hypereosinophilias and apart from pathologies covered in Note III, diseases of the connective tissue, neoplasias, blood diseases and other conditions are also examined. Two connective tissue diseases often accompanied by hypereosinophilias are Churg and Strauss angiitis and eosinophilic fascitis. Churg and Strauss angiitis (of which 2 personal cases are reported) is a systemic vasculitis usually seen in combination with bronchial asthma and haematic eosinophilia. Eosinophilic fascitis is quite rare and poorly understood. Its symptoms include hardening of the skin and eosinophilia and it is difficult to differentiate from progressive systemic sclerosis. The possible reasons why hypereosinophilia sometimes accompanies benign and more often malignant tumours are discussed. The pathogenesis of the hypereosinophilias encountered in diseases of the blood is still controversial. One hypothesis is that hypereosinophilia is an intrinsic symptom of the blood disease, others believe it to be an immunological response. In this context two personal cases are reported as examples: one of hypereosinophilia in a malignant non-Hodgkins lymphoma, the second in an IgG plasmacytoma. Particular attention was paid to the hypereosinophilia that accompanies the rare blood disease known as angioimmunoblastic lymphoadenopathy with dysproteinaemia (LAID) of which a personal case is reported.

[Blood hypereosinophilias. III. Symptomatic hypereosinophilias: allergic, cutaneous, parasitic, infective, pulmonary and gastro- intestinal diseases]

The most frequently observed of the symptomatic hypereosinophilias are those caused by allergic, cutaneous, parasitic, infectious, pulmonary and gastroenteric conditions. Among the allergic conditions, particular attention is paid to the hypereosinophilias caused by allergic asthma, gastroenteritis and reactions to drugs. The most common skin conditions linked to hypereosinophilias such as bullous dermatites and angio-oedema are considered. Turning to the parasitic conditions, the various types of parasite that may produce hypereosinophilias by infesting the organs are examined. The aetiology of tropical eosinophilias and the pathogenetic mechanism that may trigger hypereosinophilias are discussed. It has been thought advisable to group the lung pathologies associated with hypereosinophilias under a separate heading, despite the indubitable importance of the allergic element in these events. Among gastroenteric conditions, the one considered is eosinophilic gastroenteritis whose clinical, anatomopathological and aetiopathogenic features are still not quite clear. Examples of certain forms of secondary hypereosinophilias are given in the form of four unusual personal cases of bronchial asthma, filariasis, an exceptional infestation by Hypoderma bovis and eosinophilic gastroenteritis.

[Hypereosinophilia of the blood. II. Classification. Benign essential hypereosinophilia. Eosinophilia caused by systemic eosinophilic hemopathies]

Following a previous note on the latest development in the study of eosinophilic granulocytes, a nosographic classification scheme is proposed for the problematic group of haematic eosinophilias. The scheme is based on the division of hypereosinophilias into three basic groups: benign idiopathic hypereosinophilias, hypereosinophiliasis caused by systemic eosinophilic blood diseases and symptomatic hypereosinophilias. Two rare events, hereditary familial eosinophilia and bening, non-familial idiopathic eosinophilia may be added to the benign idiopathic hypereosinophilias group. The group of hypereosinophilias caused by systemic eosinophilic blood diseases is still controversial and difficult to interpret. Particular attention is paid to the so-called "idiopathic hypereosinophilic syndrome" (HES), an umbrella term under which there is a current tendency to group a heterogeneous series of disorders characterised by long-lasting hypereosinophilia where there is no known reason for the increased eosinophilic granulocyte rate. Clinical and physiopathological features are then described to decide whether a given condition lies within the scope of this still little known syndrome.

[Hypereosinophilias of the blood. I. Eosinophilic granulocytes]

A knowledge of eosinophil granulocytes is indispensable for the study of hypereosinophilia. For this reason, the most recent findings relating to eosinophil morphology, production/regulation mechanism, and function are reported. Particular attention is given to enzyme populations, local control mechanisms and eosinophil cell surface receptors. Among the various enzymes present in the eosinophil, major basic protein (MBP), with its capacity to damage the cells of many organs, plays an important part; other enzymes include eosinophil peroxidase (EPO), arylsulphatase B, phospholipase D, histaminase and cationic proteins (ECP). Factors influencing eosinophil tissue concentrations and mode of action are considered. Recent findings agree on the role of eosinophils in immunological reactions and parasitic infestations: eosinophil plays a part in an immunological physiopathological sequence: it may, act as a killer cell with selective action against invading parasites, or it may be an immune modulator, anti-inflammatory cell able to surround inflammatory reactions and prevent them from spreading.