The human carotid atherosclerotic plaque: an observational review of histological scoring systems.

OBJECTIVE: The atherosclerotic plaque is a complex dynamic pathological lesion of the arterial wall, characterized by multiple elementary lesions of different diagnostic and prognostic significance. Fibrous cap thickness, lipid necrotic core dimension, inflammation, intra-plaque hemorrhage (IPH), plaque neovascularization and endothelial dysfunction (erosions) are generally considered the most relevant morphological details of plaque morphology. In this review, the most relevant features able to discriminate between stable and vulnerable plaques at histological level are discussed. SUBJECTS AND METHODS: Retrospectively, we have evaluated the laboratory results from one hundred old histological samples from patients treated with carotid endarterectomy. These results were analyzed to assess elementary lesions that characterize stable and unstable plaques. RESULTS: A thin fibrous cap (<65 micron), loss of smooth muscle cells, collagen depletion, a large lipid-rich necrotic core, infiltrating macrophages, IPH and intra-plaque vascularization are identified as the most important risk factors associated with plaque rupture. CONCLUSIONS: Immunohistochemistry for smooth muscle actin (smooth muscle cell marker) and for CD68 (marker of monocytes/macrophages) and glycophorin (marker of red blood cells) are suggested as useful tools for an in deep characterization of any carotid plaque and for distinguishing plaque phenotypes at histology. Since patients with a carotid vulnerable plaque are at higher risk of developing vulnerable plaques in other arteries as well, the definition of the vulnerability index is underlined, in order to stratify patients at higher risk for undergoing cardiovascular events.

Expression of L1 Cell Adhesion Molecule (L1CAM) in extracellular vesicles in the human spinal cord during development.

OBJECTIVE: L1  cell adhesion molecule (L1CAM) is a glycoprotein characterized by three components: an extracellular region, a transmembrane segment, and a cytoplasmic tail. L1CAM is expressed in multiple human cells, including neurons. The neural cell adhesion molecule L1 has been implicated in a variety of neurologic processes, including neuritogenesis and cerebellar cell migration. The presence of L1CAM on the surface of nerve cells allows the adhesion of neurons among them. Furthermore, when it is bound to itself or to other proteins, L1-CAM induces signals inside the cell. The aim of this work was to study L1CAM expression in the human spinal cord during development, at different gestational ages, through immunohistochemistry. MATERIALS AND METHODS: Immunohistochemical analysis for L1CAM was performed in five human spinal cord samples, including three embryos and two fetuses of different gestational ages, ranging from 8 to 12 weeks. RESULTS: L1CAM expression was detected in all 5 spinal cords examined in this study. The adhesion molecule was found in the vast majority of cells. The highest levels of immunoreactivity for L1CAM were detected at the periphery of the developing organs, in the spinal cord zones occupied by sensory and motor fibers. In the alar and basal columns, immunoreactivity for L1CAM was characterized by a reticular pattern, being mainly expressed in axons. Strong reactivity of L1CAM was also found in extracellular vesicles. This extracellular localization might indicate the ability of L1CAM to mediate the transduction of extracellular signals that support axon outgrowth. CONCLUSIONS: The high reactivity of L1cam in the axons of developing neurons in the fetal spinal cord confirms previous studies on the ability of L1CAM to promote axon sprouting and branching in the developing nervous system. In this work, a new actor is reported to have a role in the complex field of human spinal cord development: L1CAM, whose expression is highly found in the developing neuronal and glial precursors.

Fetal programming of atherosclerosis: may the barker hypothesis explain the susceptibility of a subset of patients to develop stroke or cardiac infarct?

The risk stratification of young adults between subjects who will develop a mild form of atherosclerosis and subjects who will undergo a severe disease remains inaccurate. In the eighties of the previous century, David JP Barker has demonstrated the relationship between fetal conditions and occurrence of pathologies in adulthood. In this paper, the multiple evidence that might explain the increased susceptibility to severe forms of atherosclerosis, including stroke and cardiac infarct, in subjects who underwent intrauterine growth restriction (IUGR) will be analyzed. Specifically, we will review those inter-connected data indicating an association between a low weight at birth and an adult phenotype which might favor a severe outcome of atherosclerosis. Young and adult subjects born too small (IUGR) or too early (pre-terms) might represent a subgroup of "at risk subjects", more susceptible toward severe forms of atherosclerosis. Given that low birth weight (LBW) may be considered a surrogate of IUGR, this phenotypic feature could be considered among those indispensable clinical data collected in every patient presenting with atherosclerosis, irrespectively of age. According to the hypothesis that structural arterial changes might represent the link between LBW and susceptibility to atherosclerosis later in life, we suggest that the prevention of atherosclerosis should begin at birth. Regenerative and physiological substances such as thymosin Beta-4 could be challenged for a new "arterial regenerative medicine" in the perinatal period. The goal of this new approach should be the reinforcement of the structure of the arterial wall, allowing LBW newborns to avoid the most severe complications of atherosclerosis later in life: a dream that our research could contribute to bringing to life.

Vaccine-induced severe thrombotic thrombocytopenia following COVID-19 vaccination: a report of an autoptic case and review of the literature.

OBJECTIVE: Vaccine-induced immune thrombocytopenia (VITT) is a new syndrome occurring primarily in healthy young adults, with a female predominance, after receiving the first dose of ChAdOx1 nCoV-19 vaccine. We describe VITT syndrome characterized by severe thrombosis and thrombocytopenia found in our patient, with fatal outcome. CASE REPORT: A 58-year-old man, after 13 days from the first administration of ChAdOx1 nCoV-19 vaccine (AstraZeneca), presented with abdominal pain, diarrhea and vomitus. Laboratory tests revealed a severe thrombocytopenia, low fibrinogen serum levels and marked increase of D-dimer serum levels. The patient quickly developed a multiple organ failure, till death, three days after the hospital admission. RESULTS: At histology, in the lungs, interalveolar septa appeared thickened with microthrombi in the capillaries and veins. Interalveolar septa appeared thickened and showed vascular proliferation. Thrombi were detected in the capillaries of glomerular tufts. In the hearth, thrombi were observed in veins and capillaries. In the liver, voluminous fibrin thrombi were diffusely observed in the branches of the portal vein. Microthrombi were also found in the vasa vasorum of the wall of abdominal aorta. In the brain, microthrombi were observed in the capillaries of the choroid plexuses. Diffuse hemorrhagic necrosis was observed in the intestinal wall with marked congestion of the venous vessels. CONCLUSIONS: In our patient, the majority of data necessary for a VITT final diagnosis were present: thrombocytopenia and thrombosis in pulmonary, portal, hepatic, renal and mesenteric veins, associated with a marked increase of D-dimer serum levels. The finding of cerebral thrombosis in choroid plexuses, is a new finding in VITT. These features are suggestive for a very aggressive form of VITT.

Trace elements and the carotid plaque: the GOOD (Mg, Zn, Se), the UGLY (Fe, Cu), and the BAD (P, Ca)?

Multiple epidemiological studies have suggested that industrialization and progressive urbanization should be considered one of the main factors responsible for the rising of atherosclerosis in the developing world. In this scenario, the role of trace metals in the insurgence and progression of atherosclerosis has not been clarified yet. In this paper, the specific role of selected trace elements (magnesium, zinc, selenium, iron, copper, phosphorus, and calcium) is described by focusing on the atherosclerotic prevention and pathogenesis plaque. For each element, the following data are reported: daily intake, serum levels, intra/extracellular distribution, major roles in physiology, main effects of high and low levels, specific roles in atherosclerosis, possible interactions with other trace elements, and possible influences on plaque development. For each trace element, the correlations between its levels and clinical severity and outcome of COVID-19 are discussed. Moreover, the role of matrix metalloproteinases, a family of zinc-dependent endopeptidases, as a new medical therapeutical approach to atherosclerosis is discussed. Data suggest that trace element status may influence both atherosclerosis insurgence and plaque evolution toward a stable or an unstable status. However, significant variability in the action of these traces is evident: some - including magnesium, zinc, and selenium - may have a protective role, whereas others, including iron and copper, probably have a multi-faceted and more complex role in the pathogenesis of the atherosclerotic plaque. Finally, calcium and phosphorus are implicated in the calcification of atherosclerotic plaques and in the progression of the plaque toward rupture and severe clinical complications. In particular, the role of calcium is debated. Focusing on the COVID-19 pandemia, optimized magnesium and zinc levels are indicated as important protective tools against a severe clinical course of the disease, often related to the ability of SARS-CoV-2 to cause a systemic inflammatory response, able to transform a stable plaque into an unstable one, with severe clinical complications.

The Role of Magnesium in Pregnancy and in Fetal Programming of Adult Diseases.

Magnesium is an essential trace metal and a necessary factor for multiple biochemical functions in humans. Its role in biology is fundamental in over 600 enzymatic reactions implicated in protein synthesis, mitochondrial functions, neuromuscular activity, bone formation, and immune system competence. Magnesium status is relevant in fetal development during gestation and in the newborn growth during the perinatal period. Moreover, magnesium is able to influence fetal programming and disease presentation in childhood or adulthood. The aim of this review is to focus on this metal homeostasis, analyzing its normal values, the causes of hypomagnesemia, the interaction with drugs and other conditions, and the diseases associated with magnesium value alteration during pregnancy, in order to study its role in fetal programming of adult diseases. The data here reported clearly indicated the existence of a connection between magnesium status and human pathology starting from intrauterine life and extending into childhood and adulthood.

Effects of iron and copper overload on the human liver: an ultrastructural study.

Iron and copper ions play important roles in many physiological functions of our body, even though the exact mechanisms regulating their absorption, distribution and excretion are not fully understood. Metal-related human pathology may be observed in two different clinical settings: deficiency or overload. The overload in liver cells of both trace elements leads to multiple cellular lesions. Here we report the main pathological changes observed at transmission electron microscopy in the liver of subjects affected by Beta-thalassemia and by Wilson's disease. The hepatic iron overload in beta-thalassemia patients is associated with haemosiderin storage both in Kupffer cells and in the cytoplasm of hepatocytes. Haemosiderin granules are grouped inside voluminous lysosomes, also called siderosomes. Other ultrastructural changes are fat droplets, proliferation of the smooth endoplasmic reticulum and fibrosis. Apoptosis of hepatocytes and infiltration of sinusoids by polymorphonucleates is also detected in beta-thalassemia. Ultrastructural changes in liver biopsies from Wilson's disease patients are characterized by severe mitochondrial changes, associated with an increased number of perossisomes, cytoplasmic lipid droplets and the presence of lipolysosomes, characteristic cytoplasmic bodies formed by lipid vacuoles surrounded by electron-dense lysosomes. In patients affected by Wilson's disease, nuclei are frequently involved, with disorganization of the nucleoplasm and with glycogen inclusions. On the contrary, no significant changes are detected in Kupffer cells. Our data show that iron and copper, even though are both transition metals, are responsible of different pathological changes at ultrastructural level. In particular, copper overload is associated with mitochondrial damage, whereas iron overload only rarely may cause severe mitochondrial changes. These differences underlay the need for further studies in which biochemical analyses should be associated with ultrastructural data, in order to better understand the molecular ways associated with iron- and copper-related pathology at subcellular level.

A developmental approach to drug-induced liver injury in newborns and children.

The liver represents the major site of drug metabolism in humans. The developmental changes that occur in the liver's metabolic activity during fetal life and in the perinatal period are at the basis of the varied sensitivity of human newborns to many drugs. The decreased capacity of the fetal and newborn liver to metabolize, detoxify, and excrete drugs--total cytochrome P450 content in the fetal liver being 30% to 60% of adult values--may explain the prolonged actions of many drugs in the newborn, as well as less their potential toxicity. On the other hand, the low levels of phase I (activation) enzymes, producing more polar reactive and often toxic metabolites, could explain the lower incidence of adverse effects of some drugs reported in newborns. Moreover, the greater capacity of newborns to synthesize glutathione is at the basis of their ability in inactivating many toxic metabolites. Here we review the acute and chronic liver toxicity due to the most widely used drugs in the neonate. We will discuss in detail the biochemical profile of the fetal and neonatal liver, and the toxic metabolites formed during the metabolism of the most widely used drugs in the neonate. The histological picture of liver disease related to the therapeutic use of drugs will be discussed, with particular emphasis on the mode of cell death involved in hepatitis induced by different drugs most frequently utilized in the neonatal intensive care units.

Genotype, serum level of hepatitis C virus RNA and liver histology as predictors of response to interferon-alpha 2a therapy in Japanese patients with chronic hepatitis C.

To determine whether pretreatment HCV-RNA level, hepatitis C virus genotypes, alanine aminotransferase and histology correlate with subsequent response to interferon-alpha therapy or not, serum HCV-RNA levels and genotype were determined by branched DNA signal amplification assay and genotype-specific polymerase chain reaction in 43 patients with chronic active hepatitis C. Response to recombinant interferon-alpha 2a (504 million units in total) was defined as complete and sustained CR-->SR, n = 12), complete response followed by relapse (CR-->Rel, n = 17), and no response (NR, n = 10), excluding dropouts (n = 4). Patients who showed CR-->SR had a lower HCV-RNA level (0.438 x 10(6) eq/ml) compared to CR-->Rel (2.452 x 10(6) eq/ml, p = 0.008) and NR (4.882 x 10(6) eq/ml, p = 0.009). A higher proportion of patients with CR-->SR had type 2a HCV (67%) compared to the CR-->Rel (28%) and the NR (0%). There was a trend for type 1b hepatitis C virus infection to have higher serum HCV-RNA levels. There was no correlation between pretreatment HCV-RNA level and alanine aminotransferase. However, no relation between pretreatment HCV-RNA level and liver histology was observed; a high proportion of patients with CAH2a showed CR-->SR, compared to those with CAH2b (p = 0.001). Moreover, the patients with CAH2b who had low level hepatitis C virus viremia did not show CR-->SR. These data indicate that pre-treatment serum HCV-RNA levels, genotype and liver histology are good predictors of subsequent response to interferon-alpha therapy in Japanese patients with chronic hepatitis C virus infection.

Treatment of chronic hepatitis D with interferon alfa-2a.

BACKGROUND AND METHODS: Chronic hepatitis D is a severe and rapidly progressive liver disease for which no therapy has been proved effective. To evaluate the efficacy of treatment with interferon, we studied 42 patients with chronic hepatitis D who were randomly assigned to receive either 9 million or 3 million units of recombinant interferon alfa-2a (three times a week for 48 weeks) or no treatment. RESULTS: By the end of the treatment period, serum alanine aminotransferase values had become normal in 10 of 14 patients receiving 9 million units (71 percent), as compared with 4 of 14 treated with 3 million units (29 percent, P = 0.029) and 1 of 13 untreated controls (8 percent, P = 0.001). Seven patients treated with the higher dose of interferon (50 percent) had a complete response (normal levels of alanine aminotransferase and no detectable serum hepatitis delta virus [HDV] RNA), as compared with three of those who received the lower dose (21 percent, P = 0.118), and none of the controls (P = 0.004). Treatment with 9 million units of interferon was associated with a marked improvement in the histologic findings (reduced periportal necrosis and portal and lobular inflammation), whereas in the untreated controls there was considerable histologic deterioration. In 5 of the 10 patients treated with 9 million units of interferon whose alanine aminotransferase values became normal, the biochemical responses persisted for up to 4 years (mean, 39 months), but the effects of treatment on viral replication were not sustained. In contrast, none of those who received 3 million units and none of the untreated controls had a sustained biochemical or virologic response. CONCLUSIONS: In about half the patients with chronic hepatitis D treated with high doses of interferon alfa-2a (9 million units three times a week for 48 weeks), the serum alanine aminotransferase level becomes normal, HDV RNA becomes undetectable in serum, and there is histologic improvement. However, a relapse is common after treatment has been stopped.

Three-dimensional ultrastructure of normal rat hepatocytes by quick-freezing and deep-etching method.

The three-dimensional ultrastructure of nuclei and cell organelles including rough-surfaced endoplasmic reticulum (RER), mitochondria, and cytoskeleton were studied in normal rat hepatocytes by the quick-freezing and deep-etching method. Peroxisomes and mitochondria were observed as spherical structures with granular matrices. Peroxisomes were identified by their size and matrices, which were more condensed than those of mitochondria. Ribosomes were identified as granular structures and were attached to the surface of endoplasmic reticulum. Cytoskeletal filaments were identified by their differences in diameter on the replica membranes, as well as in conventional ultrathin sections. Microfilaments were mainly localized around the bile canaliculi and adjacent to sinusoids. Intermediate filaments were observed around the bile canalicular microfilaments. Only a few filaments were observed near the lateral plasma membranes. Cross-bridges measuring 5-7 nm in diameter were localized between the lamellae of RER and the surface of mitochondria. The quick-freezing and deep-etching method could be used to clarify the three-dimensional association between the cytoskeleton and membrane-bound organelles in hepatocytes.

Study of the usefulness and the limits of ultrasonic diagnostic criteria for diagnosis of liver tumours.

We studied the usefulness and the limits of the ultrasonic diagnostic criteria for liver tumours formulated by the Japan Society of Ultrasonics in Medicine (JSUM). 226 cases with liver mass lesions were enrolled in this study. At least one of the criteria reached a value of over 80% for one of the items: sensitivity, specificity, positive predictive value, negative predictive value or overall accuracy. In the differentiation of liver tumours, sharp & smooth boundary, presence of marginal hypoechoic zone, mosaic pattern, starry anechoic area, posterior echo enhancement and lateral shadows were important for HCC. For metastatic liver cancer, potato shape, coarsely irregular boundary, presence of marginal hypoechoic zone, internal target like anecho were important features. The liver pathology of the false negative cases corresponded to: a) liver tissue completely replaced or infiltrated by HCC or metastasis. b) the non-tumour tissue and tumour tissue were isoechoic but also without marginal hypoechoic zone. c) the ultrasonograms of non tumoural areas were modified by calcification of eggs of schistosomiasis and severe fibrosis. It can be concluded that most HCC and metastatic liver cancers over 3 cm in diameter can be diagnosed correctly by the JSUM's criteria. However, complimentary image diagnosis and fine needle biopsy are important to assure the highest diagnostic score in cases with US negative and small tumours.

Ultrastructural studies of hepatocyte cytoskeleton in experimental cholestasis by quick-freezing and deep-etching method.

The ultrastructural association between the cytoskeleton and other organelles was studied by the quick-freezing and deep-etching method in rats treated with alpha-naphthylisothiocyanate (ANIT), or phalloidin, and in rats with obstructive jaundice. Cytoplasmic filaments were classified by measuring their diameters, and actin filaments were identified by specific decoration with myosin subfragment 1 (S1). S1-positive actin filaments and S1-negative intermediate filaments (12-14 nm in diameter) were observed to form a three-dimensional network around bile canaliculi, and were more numerous than in controls, not only in phalloidin-treated rats and rats with obstructive jaundice, but also in ANIT-administered rats. In all cholestatic rats, vesicular structures were also more numerous than in controls in the pericanalicular regions, and were closely associated with the microfilaments and the intermediate filaments. Filaments of a new type were localized between the lamellae of rough-surfaced endoplasmic reticulum and mitochondria, and between the lamellae of Golgi sacs and vesicles. Other thin filaments were also observed within the network of actin filaments. These filaments were 4-6 nm in diameter on replica membranes and were never decorated with S1. They were also directly connected with the canalicular membranes. Cytoskeletal components associated with membrane-bound organelles, including these new filaments, were suggested to be involved in the localization and migration of organelles.

Interrelationship of blood transfusion, non-A, non-B hepatitis and hepatocellular carcinoma: analysis by detection of antibody to hepatitis C virus.

To clarify the relationship between hepatitis C virus infection and the development of hepatocellular carcinoma as sequelae of non-A, non-B posttransfusion hepatitis, 231 patients with chronic non-A, non-B hepatitis (96 with chronic hepatitis, 81 with cirrhosis and 54 with hepatocellular carcinoma) were analyzed for antibody to hepatitis C virus and were compared with 125 patients with chronic hepatitis B (50 with chronic hepatitis, 46 with cirrhosis and 29 with hepatocellular carcinoma). Antibody to hepatitis C virus was detected in 89.6%, 86.4% and 94.4% of patients with non-A, non-B hepatitis-related chronic hepatitis, cirrhosis and hepatocellular carcinoma, respectively, compared with 6%, 17.4% and 34.5% with similar diseases related to hepatitis B. A history of transfusion was documented in 52%, 33% and 42% of anti-hepatitis C virus-positive cases of chronic hepatitis, cirrhosis and hepatocellular carcinoma. The mean intervals between the date of transfusion and the date of diagnosis of anti-hepatitis C virus-positive chronic hepatitis, cirrhosis and hepatocellular carcinoma were 10, 21.2 and 29 yr, respectively. In 21 patients with transfusion-associated hepatocellular carcinoma, anti-hepatitis C virus was present in each serial sample available for testing, including samples obtained up to 14 yr before the diagnosis of hepatocellular carcinoma. These data suggest the slow, sequential progression from acute hepatitis C virus-related non-A, non-B hepatitis through chronic hepatitis and cirrhosis to hepatocellular carcinoma and support a causal association between hepatitis C virus and hepatocellular carcinoma.

[Infection by non-A, non-B acute viral hepatitis in hospital employees].

The aim of this study is to evaluate the risk of infection of non-A, non-B acute hepatitis (NANB-AH) in hospital employees. Among 593 patients with acute viral hepatitis (AVH), hospital employees were 3/147 (2%) in type A, 19/174 (11%) in type B and 21/272 (8%) in non-A, non-B (NANB). All 43 patients were medical staffs such as doctors, nurses and laboratory technicians. Out of 21 patients with NANB hepatitis of hospital employees, 7 were doctors, 14 nurses and 6 laboratory technicians. Eight of them had preceding accidental needlestick exposures. Out of 17,290 employees of our hospital during 18 years, 27 medical persons developed AVH. They were 2 hepatitis A, 10 hepatitis B and 15 hepatitis NANB. No non-medical staff developed AVH. Out of 15 NANB hepatitis patients, 7 had needlestick accidents 4 to 6 weeks before development of the illness, and all donor patients showed liver diseases. During 3 years (1985 to 1987), there were 116 needlestick accidents in our hospital which happened in medical staffs alone, and 50 of them were NANB hepatitis-related accidents. Three ml of human immune serum globulin (ISG) was administered intramuscurally just after accidents to 23 persons but not to 27 persons. NANB hepatitis were developed in 2 doctors who were not treated with ISG. In conclusion, NANB hepatitis occurred in hospital employees especially in medical staffs.

A case of cholangiocarcinoma detected after follow-up for seven years for thorotrast deposition.

A 73-year-old former soldier in whom a deposition of thorotrast had been detected 7 years previously was admitted to our hospital because of high fever and epigastric pain. He had been well with standard liver function tests within the normal range until 4 months before admission. Laboratory examination on admission showed marked abnormalities in the liver function tests and an elevated level of CEA. Abdominal ultrasonography and computerized tomography, which had shown no space-occupying lesion in the liver one year earlier, revealed an abnormal mass in the right hepatic lobe. Angiographic examination revealed low vascularity and encasement of the intrahepatic artery. The disease was diagnosed as thorotrast-induced cholangiocarcinoma. Despite chemotherapy, the patient's condition worsened rapidly and he died on the 78th day after admission. At autopsy, the primary tumor in the right hepatic lobe and metastatic nodular tumors throughout the liver were found. The histological diagnosis was cholangiocarcinoma. Thorotrast-induced liver cancers are inclined to grow rapidly, so early diagnosis of liver tumor accompanied by thorotrastosis is very difficult, as in this case. Repeated examinations at frequent intervals are required for early diagnosis.

Possible infectious causes in 651 patients with acute viral hepatitis during a 10-year period (1976-1985).

Six hundred and fifty-one patients with acute viral hepatitis were identified serologically between January 1976 and December 1985. Of these, 109 (17%) had hepatitis A, 135 (21%) had hepatitis B, and 407 (62%) had hepatitis non-A, non-B. The possible infectious causes for acquisition of viral hepatitis occurring within 6 months before the onset of hepatitis were analysed. Approximately 80% of cases of hepatitis A and 70% of hepatitis B had no known risk factor, while in 67% of cases of hepatitis non-A, non-B possible risk factors for infection were documented. Infectious causes for hepatitis A were ingestion of raw shellfish (11%) and previous familial contact with patients with hepatitis A (10%). For hepatitis B, risk factors included medicare (24%), such as transfusion, surgical operation, accidental needle stick and acupuncture, and sexual contact (6%). For hepatitis non-A, non-B, the most important infectious cause was medical procedures (65%). The numbers of hospital employees were 2 (2%) with hepatitis A, 15 (11%) with hepatitis B and 14 (3%) with hepatitis non-A, non-B. These data suggest that hepatitis non-A, non-B can be a kind of nosocomial disease.