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Drug-induced phospholipidosis (PL) is a storage disorder caused by the formation of phospholipid-drug complexes in lysosomes. Because of the diversity of PL between species, human cell-based assays have been used to predict drug-induced PL in humans. We established three-dimensional (3D) human liver organoids as described previously and investigated their liver characteristics through multiple analyses. Drug-induced PL was initiated in these organoids and in monolayer HepG2 cultures, and cellular changes were systemically examined. Organoids that underwent differentiation showed characteristics of hepatocytes rather than HepG2 cells. The organoids also survived under PL-inducing drug conditions for 48 h and maintained a more stable albumin secretion level than the HepG2 cells. More cytoplasmic vacuoles were observed in organoids and HepG2 cells treated with more potent PL-induced drugs, but to a greater extent in organoids than in HepG2 cells. Lysosome-associated membrane protein 2, a marker of lysosome membranes, showed a stronger immunohistochemical signal in the organoids. PL-distinctive lamellar bodies were observed only in amiodarone-treated organoids by transmission electron microscopy. Human liver organoids are thus more sensitive to drug-induced PL and less affected by cytotoxicity than HepG2 cells. Since PL is a chronic condition, these results indicate that organoids better reflect metabolite-mediated hepatotoxicity in vivo and could be a valuable system for evaluating the phospholipidogenic effects of different compounds during drug development.

Phospholipidosis is characterized by the presence of excessive accumulation of phospholipids in different tissue types (lungs, liver, eyes, kidneys etc.) caused by cationic amphiphilic drugs. Electron microscopy analysis has revealed the presence of lamellar inclusion bodies as the hallmark of phospholipidosis. Some phospholipidosis causing compounds can cause tissue specific inflammatory/retrogressive changes. Reliable and accurate in silico methods could facilitate early screening of phospholipidosis inducing compounds which can subsequently speed up the pharmaceutical drug discovery pipelines. In the present work, stacking ensembles are implemented for combining a number of different base learners to develop predictive models (a total of 256 trained machine learning models were tested) for phospholipidosis inducing compounds using a wide range of molecular descriptors (ChemMine, JOELib, Open babel and RDK descriptors) and structural alerts as input features. The best model consisting of stacked ensemble of machine learning algorithms with random forest as the second level learner outperformed other base and ensemble learners. JOELib descriptors along with structural alerts performed better than the other types of descriptor sets. The best ensemble model achieved an overall accuracy of 88.23%, sensitivity of 86.27%, specificity of 90.20%, mcc of 0.765, auc of 0.896 with 88.21 g-means. To assess the robustness and stability of the best ensemble model, it is further evaluated using stratified 10×10 fold cross validation and holdout testing sets (repeated 10 times) achieving 84.83% mean accuracy with 0.708 mean mcc and 88.46% mean accuracy with 0.771 mean mcc respectively. A comparison of different meta classifiers (Generalized linear regression, Gradient boosting machines, Random forest and Deep learning neural networks) in stacking ensemble revealed that random forest is the better choice for combining multiple classification models., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Hepatic lipidosis (HL) is a well-known disease in fattening and in parent turkey flocks. Among others, dietary effects like (a lack of) essential amino acids (AA) as lipotrophic factors (e.g., methionine) have been considered as potentially predispositing for HL. Several studies have reported abnormal AA profiles in hepatic diseases of humans and other livestock. The ratio of branched-chain amino acids (BCAA) to aromatic amino acids (AAA) in plasma is used to predict hepatic cirrhosis. In this study, the state of supply of AA was investigated by comparing non-affected (NA) animals and those affected by HL. The AA pattern in the liver and blood can provide potential indications of pathogenesis of HL. In cooperation with German poultry veterinarians, 3 cases of HL on 3 different fattening turkey farms were visited (13/14 wk old, "B.U.T. Big 6" and "TP7"). Overall, 73 birds were examined, of which 42 birds suffered from HL and 31 were not affected. Feeding samples of the respective actual feed were taken and analyzed. The selection of animals was carried out (NA randomly) by clinical signs such as apathy and dyspnea and the diagnosis was made at necropsy, which could be confirmed by crude fat content in liver tissue (HL: 309, NA: 155). In liver tissue, the CP and AA contents were lower among animals with HL than among NA (P < 0.05). In blood samples, the sum of AA, ammonia, and urea was more than 3 times higher among animals with HL (431 mg/dL serum) than among NA (114 mg/dL serum; P < 0.01). The ratio of BCAA to AAA was also significantly different between the groups (HL: 0.85, NA: 1.42; P < 0.05). In the case of HL, entire herds were not affected and the "non-affected" ones were comparable with healthy slaughtered animals. There seems to be a clear change in protein and AA metabolism of HL animals, which could lead to an optimization in feeding practice in repeated cases of HL., (© The Author(s) 2019. Published by Oxford University Press on behalf of Poultry Science Association.)

Whole body cytosolic phosphoenolpyruvate carboxykinase knockout (PEPCK-C KO) mice die early after birth with profound hypoglycemia therefore masking the role of PEPCK-C in adult, non-gluconeogenic tissues where it is expressed. To investigate whether PEPCK-C deletion in the liver was critically responsible for the hypoglycemic phenotype, we reexpress this enzyme in the liver of PEPCK-C KO pups by early postnatal administration of PEPCK-C-expressing adenovirus. This maneuver was sufficient to partially rescue hypoglycemia and allow the pups to survive and identifies the liver as a critical organ, and hypoglycemia as the critical pathomechanism, leading to early postnatal death in the whole-body PEPCK-C knockout mice. Pathology assessment of survivors also suggest a possible role for PEPCK-C in lung maturation and muscle metabolism.

Apolipoprotein E deficiency (ApoE(-/-)) combined with a high-fat Western-type diet (WD) is known to activate the toll-like receptor (TLR4) pathway and promote atherosclerosis. However, to date, the pathogenic effects of these conditions on the lung have not been extensively studied. Therefore, the present study examined the effects of ApoE(-/-) and a WD on lung injury and investigated the underlying mechanisms. ApoE(-/-) and wild-type mice were fed a WD or normal chow diet for 4, 12 and 24 weeks. Lung inflammation, lung cholesterol content and cytokines profiles in broncho-alveolar lavage fluid (BALF) were determined. TLR4 and its main downstream molecules were analyzed with western blot analysis. In addition, the role of the TLR4 pathway was further validated using TLR4-targeted gene silencing. The results showed that ApoE(-/-) mice developed lung lipidosis following 12 weeks of receiving a WD, as evidenced by an increased lung cholesterol content. Moreover, dependent on the time period of receiving the diet, those mice exhibited pulmonary inflammation, which was manifested by initial leukocyte recruitment (at 4 weeks), by increased alveolar septal thickness and mean linear intercept as well as elevated production of inflammation mediators (at 12 weeks), and by granuloma formation (at 24 weeks). The expression levels of TLR4, myeloid differentiation primary response 88 (MyD88) and nuclear factor kappa B were markedly upregulated in ApoE(-/-) WD mice at week 12. However, these effects were ameliorated by shRNA-mediated knockdown of TLR4. By contrast, ApoE(-/-) ND or wild-type WD mice exhibited low-grade or no inflammation and mild lipidosis. The levels of TLR4 and MyD88 in those mice showed only minor changes. In conclusion, ApoE deficiency acts synergistically with a WD to trigger lung lipidosis and inflammation at least in part via TLR4 signaling.

During a nearby construction project, a sudden decrease in food intake and guano production occurred in an outdoor colony of big brown bats (Eptesicus fuscus), and one animal was found dead. Investigation revealed that the project was generating a large amount of noise and vibration, which disturbed the bats' feeding. Consequently the bats were moved into an indoor enclosure away from the construction noises, and the colony resumed eating. Over the next 3 wk, additional animals presented with clinical signs of lethargy, weight loss, ecchymoses, and icterus and were necropsied. Gross necropsy of the affected bats revealed large, pale yellow to tan, friable livers with rounded edges that floated when placed in 10% neutral-buffered formalin. Some bats had ecchymoses on the webbing and skin and gross perirenal hemorrhage. Histologic examination showed hepatic and renal tubular lipidosis. The clinical and pathologic signs of hemorrhage and icterus were suggestive of hepatic failure. Hepatic lipidosis was attributed to stress and inappetence associated with environmental perturbations. Once the environmental stressor was removed, the colony morbidity and mortality decreased. However, 2 y later, a series of new environmental stressors triggered additional deaths associated with hepatic lipidosis. Over a 9-y period, 21 cases of hepatic lipidosis were diagnosed in this bat colony.

White striping is a condition in broiler chickens characterized grossly by the occurrence of white striations, seen parallel to the direction of muscle fibers, on broiler breast fillets and thighs. Based on visual evaluation of the intensity of white striping, breast fillets can be categorized into normal (NORM), moderate (MOD), and severe (SEV) categories. This study was undertaken to evaluate the details of changes in histology as well as proximate composition occurring in the fillets with respect to the 3 degrees of white striping. In experiment 1, representative breast fillets for each degree of white striping (n = 20) were collected from 45-d-old broilers, approximately 2 h postmortem. From each fillet, 2 skeletal muscle samples were obtained and fixed in 10% neutral buffered formalin. To identify and differentiate the histological changes, slides were prepared and stained using hematoxylin and eosin, Masson's Trichrome, and Oil Red O stains. In experiment 2, samples with 3 degrees of white striping were collected from 57-d-old birds for conducting proximate analysis. Major histopathological changes observed in the MOD and SEV samples consisted of loss of cross striations, variability in fiber size, floccular/vacuolar degeneration and lysis of fibers, mild mineralization, occasional regeneration (nuclear rowing and multinucleated cells), mononuclear cell infiltration, lipidosis, and interstitial inflammation and fibrosis. Microscopic lesions were visually scored for degeneration and necrosis, fibrosis, and lipidosis. The scale used to score the samples ranged from 0 (normal) to 3 (severe). There was an increase (P < 0.05) in mean scores for degenerative or necrotic lesions, fibrosis, and lipidosis as the degree of white striping increased from NORM to SEV. The results from the histopathological study were supported by the findings from proximate analysis confirming that the fat and protein contents of muscle increased (P < 0.05) and decreased (P < 0.05), respectively, as the degree of white striping increased. In conclusion, the histopathological changes occurring in white striping indicate a degenerative myopathy that could be associated with increased growth rate in birds.

Lipidoses are rare genetic disorders characterized by defects of the digestive system that impair the way the body uses dietary fat. When the body is unable to properly digest fats, lipids such as cholesterol, sphingolipids or glycolipids may accumulate in body tissues in abnormal amounts. It has been also suggested that molecular mechanisms leading to development of human diseases, including obesity, diabetes type II and atherosclerosis, consist of impaired transport and storage of lipids, as well as disturbed structure and function of lipid membrane microdomains. In this review we discuss probable mechanisms, including role of lipid membrane microdomains, which may participate in pathogenesis of lipid storage diseases such as Niemann-Pick type A/B and type C, as well as Gaucher type I diseases.

Alagille syndrome is characterized by a paucity of interlobular bile ducts with chronic cholestasis, cardiac, skeletal, and eye abnormalities and is associated predominantly with JAG1 mutations. Various renal abnormalities have been sporadically described. The classic renal histopathology described in Alagille syndrome is mesangiolipidosis, with lipid deposits predominately confined to the mesangium and minimal deposition within the glomerular basement membrane (GBM). We report a 5-year-old girl with Alagille syndrome who presented with persistent subnephrotic proteinuria and renal tubular acidosis. A renal biopsy showed GBM irregularities (mimicking membranous glomerulonephritis), mesangial sclerosis, and focal segmental glomerulosclerosis (FSGS) on light microscopy. Electron microscopy revealed few lipid inclusions within the mesangium but extensive inclusions along the GBM. These findings are mostly consistent with those reported previously in Alagille syndrome. However, the histologic distribution of lipid vacuoles is seemingly reversed in this patient and is uniquely accompanied by FSGS, emphasizing the spectrum of renal histopathology seen in Alagille syndrome. The proteinuria observed in this patient is likely attributed to significant GBM lipid deposition, which over time may contribute to the development of FSGS.

Phospholipid bilayers represent a complex, anisotropic environment fundamentally different from bulk oil or octanol, for instance. Even "simple" drug association to phospholipid bilayers can only be fully understood if the slab-of-hydrocarbon approach is abandoned and the complex, anisotropic properties of lipid bilayers reflecting the chemical structures and organization of the constituent phospholipids are considered. The interactions of drugs with phospholipids are important in various processes, such as drug absorption, tissue distribution, and subcellular distribution. In addition, drug-lipid interactions may lead to changes in lipid-dependent protein activities, and further, to functional and morphological changes in cells, a prominent example being the phospholipidosis (PLD) induced by cationic amphiphilic drugs. Herein we briefly review drug-lipid interactions in general and the significance of these interactions in PLD in particular. We also focus on a potential causal connection between drug-induced PLD and steatohepatitis, which is induced by some cationic amphiphilic drugs.

The number of people keeping reptiles in captivity has markedly increased, and widespread inappropriate husbandry will result in an increasing incidence of the diagnosis of hepatic lipidosis(HL). It may become apparent that some species of snake have predisposition to develop HL. In the specific instance of the genus Aspidites, alterations to the usual husbandry that limit feeding and thereby body weight should markedly lessen the chance of the animal's developing HL. It is important for clinicians to develop a more aggressive approach to these cases and to build a bank of data with which to promote understanding of this common malady.

Numerous drugs containing a cationic amphiphilic structure are capable of inducing phospholipidosis in cells under conditions of in vivo administration or ex vivo incubation. The principal characteristics of this condition include the reversible accumulation of polar phospholipids in association with the development of unicentric or multicentric lamellated bodies within cells. There is an abundance of data providing an understanding of potential mechanisms for the induction of phospholipidosis; however, the process is likely to be complex and may differ from one drug to another. The functional consequences of the presence of this condition on cellular or tissue function are not well understood. The general consensus is that the condition is an adaptive response rather than a toxicological manifestation; however, additional studies to examine this question are needed. Until this issue is resolved, concerns about phospholipidosis will continue to exist at regulatory agencies. Procedures for the screening of potential phospholipogenic candidate compounds are available. In contrast, a clear need exists for the identification of valid biomarkers to assess the development of phospholipidosis in preclinical and clinical studies.

Rare diffuse infiltrative lung diseases are a challenge for clinicians, radiologists, and pathologists for at least three reasons: (a) their low incidence and prevalence hamper the acquisition of expertise and frequently the diagnosis is delayed; (b) therapeutic actions are mainly empirical and based on steroid use, and (c) pathogenetic events are difficult to explain and only recently new therapeutic measures taking advantage of innovative genetic and/or immunopathogenetic studies have been suggested. In this review rare diffuse lung disorders are briefly discussed (pulmonary alveolar proteinosis, inherited lipidoses, acute eosinophilic pneumonia, amyloidosis, pulmonary ossification, pulmonary alveolar microlithiasis). The list is obviously not exhaustive and arbitrarily chosen. The intent is, however, to emphasize that in this difficult field multidisciplinary expertise and the knowledge of the most recent pathogenetic mechanisms have the main role in diagnosis and treatment.

Anorexia in obese cats may result in feline hepatic lipidosis (FHL). This study was designed to determine plasma lipids and lipoprotein profiles in queens at different stages during experimental induction of FHL (lean, obese, FHL), and after 10 weeks of treatment. Results were compared with those obtained from lean queens of same age fed the same diet but at a maintenance level, once a day. Hepatic lipidosis led to an increase in plasma triacylglycerol (TG), very low density lipoprotein (VLDL) and low density lipoprotein (LDL), and an enrichment of LDL with TG and of high density lipoprotein (HDL) with cholesterol, suggesting that VLDL secretion is enhanced, VLDL and LDL catabolism is lowered, and lipoprotein exchanges are impaired in FHL. This study also showed that cholesterolaemia is increased in cats fed at a dietary rhythm of one meal per day compared to ad libitum feeding.

A sheep flock experienced losses in weaned lambs from myopathy and hepatic lipidosis. Investigation revealed painful ambulation, illthrift, and unexpected death in lambs with normal selenium levels, deficient vitamin E levels, and elevated muscle and liver enzyme levels. Vitamin E deficiency should be considered when investigating myopathy and illthrift in lambs.

To evaluate the association between corneal lipid infiltration (corneal arcus) and dietary cholesterol in Cuban tree frogs (Osteopilus septentrionalis), 47 wild-caught frogs were fed diets of either regular or high-cholesterol crickets containing 0.7% and 1.7% cholesterol dry matter, respectively. Serum total cholesterol and triglycerides were measured when the frogs were euthanized after 17 mo. In a subsample of frogs, serum lipoproteins were characterized using high-performance liquid chromatography. The first case of corneal lipid deposition occurred in a female frog after 13 mo on the high-cholesterol diet. In the subsequent 4 mo, 5/11 males and 11/35 females developed the disease. Four of these affected frogs were females on the regular diet. Frogs with corneal lipid deposition had elevated serum total cholesterol (27.3 +/- 19.8 mmol/L) and low-density lipoproteins (LDL, 17.8 +/- 18.9 mmol/L) compared with unaffected captive frogs (16.5 +/- 20.4 and 9.0 +/- 7.6 mmol/L, respectively). Corneal lipid deposition was more prevalent in frogs on the high-cholesterol diet, and this group had higher serum total cholesterol (34.1 +/- 15.2 mmol/L in females, 22.8 +/- 14.8 mmol/L in males) than did frogs on the diet of regular crickets (12.3 +/- 8.7 mmol/L in females, 10.4 +/- 3.1 mmol/L in males). Captive frogs on both diets had higher serum total cholesterol than did wild frogs (3.1 +/- 2.1 mmo/L in females, 5.3 +/- 2.6 mmo/L in males). This additional serum cholesterol was primarily carried on very low-density lipoproteins (VLDL) and LDL rather than high-density lipoproteins (HDL), as indicated by the significantly higher ratio of VLDL cholesterol and LDL cholesterol over HDL cholesterol in captive frogs compared with wild frogs. Elevation in this ratio was significantly higher in captive females than in captive males. There was no evidence that increased serum cholesterol in captive females was directly related to the process of vitellogenesis.

Objective: To identify factors associated with hepatic lipidosis (HL) in llamas and alpacas., Design: Retrospective case series., Animals: 30 llamas and 1 alpaca., Procedures: Medical records were searched to identify llamas or alpacas in which a histologic diagnosis of HL was made. Information was retrieved on signalment, history, clinical and laboratory findings, and results of necropsy or examination of biopsy specimens. Data were analyzed using descriptive statistics and chi 2 analyses., Results: Females were affected more often than males; however, the sex distribution was not different from that of the camelid population in the diagnostic laboratory's database. Fifty-four percent of the females were pregnant, and 46% were lactating. Most affected camelids were 6 to 10 years old. Anorexia and recent weight loss were common (51.6% of camelids). An infective agent was found in only one ilama, and toxins and mineral deficiencies were not identified. The most common abnormalities on serum biochemical analysis were a high concentration of bile acids, high activities of gamma-glutamyltransferase (GGT) and aspartate aminotransferase (AST), and hypoproteinemia. Concentrations of nonesterified fatty acids (NEFA) and beta-hydroxybutyrate (beta-HB) were high in those camelids in which these compounds were assayed. Twenty-nine camelids did not survive., Clinical Implications: Sick camelids should be considered at risk for developing HL, especially those with anorexia or the metabolic demands of pregnancy and lactation. Other stresses also appear to contribute. High concentrations of NEFA, beta-HB, and bile acids; high activities of GGT and AST; and hypoproteinemia may indicate that HL has developed.

Objective: To determine clinical signs, clinicopathologic abnormalities, prevalence of concurrent disease, treatment, complications of treatment, and outcome in cats with diabetic ketosis (DK) or diabetic ketoacidosis (DKA)., Design: Retrospective study., Animals: 42 cats with DK or DKA., Procedure: Medical records of diabetic cats with ketonuria were reviewed., Results: In 26 cats, diabetes was newly diagnosed; in 16, diabetes had been diagnosed previously and cats had been treated with insulin (n = 14) or sulfonylurea drugs (2). Common clinical findings were lethargy, anorexia, polyuria, polydipsia, and weight loss. Common laboratory findings were hyperglycemia, hyponatremia, hypochloremia, hypokalemia, hypocalcemia, hypophosphatemia, low total CO2 content, hyperosmolality, high serum alanine transaminase activity, azotemia, glycosuria, and ketonuria. Concurrent disorders were identified in 39 cats and included hepatic lipidosis, cholangiohepatitis, pancreatitis, chronic renal failure, urinary tract infection, and neoplasia. Treatment of DK and DKA included administration of regular crystalline (34 cats), NPH (6), or ultralente (2) insulin, intravenous (38) or subcutaneous (4) administration of fluids, and enterall parenteral or administration of antibiotics (42). Complications during treatment included abnormalities in serum electrolyte concentrations (27 cats), hemolytic anemia (4), hypoglycemia (3), and neurologic abnormalities unrelated to hypoglycemia (2). Eleven cats died or were euthanatized during the initial hospitalization period for treatment of DK or DKA. Azotemia, metabolic acidosis, and hyperosmolality were more severe in cats that died than in cats that survived. Differences in regard to treatment or complications were not apparent between cats that died and cats that survived. The 31 cats that survived were discharged 1 to 16 days (median, 5 days) after initiation of insulin treatment. Diabetic ketosis or ketoacidosis recurred in 13 (42%) of these cats., Clinical Implications: A thorough diagnostic evaluation should be performed on cats with DK or DKA to identify concurrent disorders, formulate an appropriate treatment plan, and provide prognostic information to the owner.

Feline IHL is a severe hepatopathy that can be treated by aggressive nutritional support. Until the underlying mechanisms of protein and lipid metabolism are understood in both healthy and ill cats, dietary therapy remains supportive. It is likely that the pathogenesis of IHL in cats is multifactorial, involving both increased fatty acid mobilization to the liver and a defect in oxidation of fatty acids or removal of VLDL. It is also possible that individual variation may play a role in the development of this disease in cats undergoing starvation. Continued studies will focus on the unique pathways of hepatic metabolism in the cat, and how these pathways are altered, leading to hepatic lipid accumulation and clinical disease. Hopefully, these studies can be applied to the prevention or treatment of IHL in cats.

Since 1988, 11 cases of a new entity, 'Lipoprotein glomerulopathy' (LG), were described in Japan. Some of these reports suggested that this glomerular lipid storage is due to excess apo E associated with heterozygous E2/3 apo E isoform. We report the first case of LG in a white European with no such lipid abnormalities. Proteinuria was discovered in 1967 when he was 42. Blood pressure and renal function were normal. Family history was negative. Renal biopsy disclosed lesions which were only understood at the time of the Japanese publications. They were composed of endocapillary glomerular deposits. Staining for lipids disclosed capillary loop obstruction with lipid droplets. Electron microscopy showed confluent droplets of various sizes obstructing capillary loops. Proteinuria progressively increased. In 1974 repeat renal biopsy showed the same lipid deposits, now associated with focal-segmental glomerulosclerosis (FSGS). Several serum lipoprotein and apolipoprotein studies ruled out any specific lipid derangement. This suggested a local glomerular disorder, presumably affecting the glomerular endocapillary disposal of lipids. A third biopsy showed progressive glomerular destruction by FSGS with persistence of the lipid droplets. Renal insufficiency progressed and haemodialysis was started in 1992. This observation suggests that LG is a local glomerular, not a general lipid disorder and indicates that this disease is not restricted to Asian patients.

Seven piglets, aged 2 weeks at the beginning of the experiment, were fed a diet lacking antioxidants (vitamin E and selenium) and enriched with thermally oxidated cod liver oil (the peroxide value of which was 310 meqv/kg). From one month before to 4 weeks after farrowing (weaning) the sow also received the experimental diet. One pig died at 9 days of age, due to degeneration of the parenchymal tissues. The oxidative stress produced was aggravated in four of the seven remaining pigs by giving them an injection of iron-dextran (300 mg) one day before the animals were killed for necropsy at the age of 2 months. The three other piglets were given an injection of a control saline solution. The nutritional myodegeneration produced ('white muscle disease') was characterized by a pale, yellowish colour and translucence of skeletal muscle, with degeneration, including swelling of the muscle fibres and slackening of the fibrillar pattern. The arrangement of nuclei in chains indicated repair. Ultrastructurally, skeletal muscle showed vacuolization of the sarcoplasmic reticulum, irregularities in the mitochondria and focal dissolution of myofibrils. The sarcoplasmic reticulum displayed condensation and lamellar formations. Hyaline degeneration of the heart muscle occurred both in iron-treated and control pigs, and in six animals a yellowish pigment resembling lipofuscin and ceroid was observed. Ultrastructurally, the ceroid deposits appeared as myelin-like figures. The livers were pale and brittle, four with centrilobular degeneration. By light microscopy, lipidosis was distinguished in four and ceroid accumulations in three pigs. Thiobarbituric-acid-reactive substances, creatine kinase activity and iron increased significantly in the serum as a result of the injection of iron-dextran.

Rats were exposed to chronic normobaric hypoxia of progressively increasing severity; down to 8% or 7% oxygen concentrations. In addition to loss of weight, pathology revealed congestion, haemorrhages, hypertrophy of the heart involving mainly the right ventricle, thickening of arteries, ischaemic changes in the myocardium and extramedullary haematopoiesis in the spleen. Changes not described up until now were: 1) sheets of foam cells in the pulmonary alveoli; 2) foamy and solid storing cells in the spleen; 3) mucoid changes in the atrioventricular valve leaflets; 4) hyperplasia of the juxtaglomerular apparatus; 5) atrophy of the adrenal glomerulosa and hyperplasia of medulla; 6) atrophy of the perifollicular B-cell zone in the spleen; and 7) lipid pigment deposition in various organs. The findings indicate that severe chronic hypoxia induces a significant pulmonary lipidosis similar to that caused by amphiphilic cationic drugs, presumably by inhibiting hydrolytic enzyme activities. The observations are of importance in human hypoxic conditions and open the possibility of their rational treatment.

Three pulmonary disease conditions result from the accumulation of phospholipids in the lung. These conditions are the human lung disease known as pulmonary alveolar proteinosis, the lipoproteinosis that arises in the lungs of rats during acute silicosis, and the phospholipidoses induced by numerous cationic amphiphilic therapeutic agents. In this paper, the status of phospholipid metabolism in the lungs during the process of each of these lung conditions has been reviewed and possible mechanisms for their establishment are discussed. Pulmonary alveolar proteinosis is characterized by the accumulation of tubular myelin-like multilamellated structures in the alveoli and distal airways of patients. These structures appear to be formed by a process of spontaneous assembly involving surfactant protein A and surfactant phospholipids. Structures similar to tubular myelin-like multilamellated structures can be seen in the alveoli of rats during acute silicosis and, as with the human condition, both surfactant protein A and surfactant phospholipids accumulate in the alveoli. Excessive accumulation of surfactant protein A and surfactant phospholipids in the alveoli could arise from their overproduction and hypersecretion by a subpopulation of Type II cells that are activated by silica, and possibly other agents. Phospholipidoses caused by cationic amphiphilic therapeutic agents arise as a result of their inhibition of phospholipid catabolism. Inhibition of phospholipases results in the accumulation of phospholipids in the cytoplasm of alveolar macrophages and other cells. While inhibition of phospholipases by these agents undoubtedly occurs, there are many anomalous features, such as the accumulation of extracellular phospholipids and surfactant protein A, that cannot be accounted for by this simplistic hypothesis.

The electroretinogram (ERG) and visually evoked cortical potential (VECP) were recorded in two cases of Tay-Sachs disease where diagnosis was well established: 1. ERGs of high amplitude and of normal wave form were recordable with prominent oscillatory potentials. Responses were always equal in both eyes. 2. VECPs were extinguished in both cases. These findings were interpreted as showing that Tay-Sachs disease is caused by the degeneration of ganglion cells in the nervous system and that the ganglion cells in the retina do not affect the ERGs of vertebrate animals.

Drugs and metastatic malignant tumors induce severe alterations in cutaneous axons. The most prominent ultrastructural feature of axonal dystrophy of this type was the presence of multiple lamellated osmiophilic bodies (LOB), similar to those occurring in hereditary disorders with increase of brain gangliosides and lipid storage. Chloroquine, ergotamine, ethaverine and chronic abuse of non-narcotic analgesic drugs seem to be responsible for the drug-induced cutaneous neuro-phospholipidosis, whereas the same condition was found in two patients with metastatic bronchogenic carcinoma and malignant melanoma.

The water-insoluble cholesterol-cholestanol-water adduct C-C-2W, chemical and physical cause of atherosclerosis and gallstones, has now been found in tendinous xanthoma as well; C-C-2W, and not cholestanol, is the initial compound deposited in hereditary CTX (cerebrotendinous xanthomatosis). From these and other findings it is theorized that what have been termed cholesterol or cholestanol lipidoses should instead be characterized as C-C-2W lipidoses. More than 1 mg of cholestanol . H2O present in the body causes crystallizaion of C-C-2W . This happens when the steroid meets cholesterol . H2O in sufficient concentration to reach a solubility product of 10(-7) mg/ml. In this light the literature can be interpreted to indicate that C-C-2W exerts negative effects on liver, intima tissue, eyes, lungs, and other parts of the body. Those effects include inflammation, cell necrosis, destruction of cell membranes, abnormal growth and, perhaps, neoplastic activity. Up to 200 g of C-C-2W in the body may be tolerated if evenly spread but not if localized in one or two areas only; e.g., the brain or the cardiovascular system. It is estimated that about 1000 g of C-C-2W, even if spread, are beyond the limit of human tolerance.

48 rats were placed on an hyperlipidic diet (cholesterol, cholic acid, cholin, propylthiouracil), 23 were sacrificed at various intervals from the fourth up to the twelve month of the experiment. In the remaining 25 rats, the atherogenic regimen was replaced by a normal one. These animals were sacrificed one to twenty months after stopping of the experimental diet. Aortae of experimental and control animals were studied by means of histological and histochemical technics. All the animals developed hypercholesterolemia together with intima and media lipoidosis. None demonstrated any aortic cell proliferation. The only metabolic change of the smooth muscle cell was a progressive decrease in 5' nucleotidase, acid esterase and cholinesterase activities. The return to a normal diet involved the reversion of the serum cholesterol level to normal values and the disappearance of intima lipoidosis. The reduced enzymatic activities in the media returned to normal levels around the sixth month. The surfaces of the extracellular sudanophilic areas decreased. However, twenty months after stopping of the atherogenic diet, some lipids still persisted at the edges of the elastic fibres.

48 rats were placed on an hyperlipidic diet (cholesterol, cholic acid, cholin, propylthiouracil), 23 were sacrificed at various intervals from the fourth up to the twelve month of the experiment. In the remaining 25 rats, the atherogenic regimen was replaced by a normal one. These animals were sacrificed one to twenty months after the withdrawal of the experimental diet. Aortae of experimental and control animals were studied by means of histological and histochemical technics. All the animals developed hypercholesterolemia together with intima and media lipoidosis. None demonstrated any aortic cell proliferation. The only metabolic change of the smooth muscle cell was a progressive decrease in 5' nucleotidase, acid esterase and cholinesterase activities. The return to a normal diet involved the reversion of the serum cholesterol level to normal values and the disappearance of intima lipoidosis. The reduced enzymatic activities in the media returned to normal levels around the six month. The surfaces of the extracellular sudanophilic areas decreased. However, twenty months after the withdrawal of the atherogenic diet, some lipids still persisted at the edges of the elastic fibres.

Foam cells in the spleen, bone marrow, liver and lymph nodes were examined on the 73 reliably recorded and sampled leukemia autopsy cases encountered at Kobe University from 1958 to 1972. Although the substances stored in the foam cells were biochemically unknown, the foam cells in leukemia could be morphologically classified into two types: The one was identified with the Gaucher type, but the other was not identified with the sea-blue type and might be considered as to be the transitional type described in another report. Foam cells could be found in the spleen of 6 out of 12 cases of chronic myeloid leukemia, one out of 2 cases of chronic lymphatic leukemia, one out of 7 cases of leukemic lymphosarcoma, one out of 9 cases of acute lymphatic leukemia, and none in 3 cases of monocytic leukemia. In acute myeloid leukemia, the incidence of foam cells in the spleen was 47.5% in 40 cases, and acquired lipidoses were more frequently seen in cases under 19 years of age, in male cases, in cases with an enlarged spleen over 400 g, and in cases of over 4 months' duration.

Lavaged pulmonary macrophages of Bio 14.6 myopathic hamsters were compared with those from Bio F1B controls. Enlarged foamy macrophages were prevalent in the dystrophic strain. Lipidosis within this cell population was confirmed by morphologic and chemical analyses. The percentage of lipid-positive cells obtained from Bio 14.6 hamsters was three times greater than from control animals, but the total number of macrophages recovered from the lungs of dystrophic animals was approximately one-third lower compared to controls. Nearly two-thirds of the lipid-positive cells from the dystrophic strain were moderately to excessively engorged, whereas a similar percentage of the positive cells from control animals contained only sparse lipid inclusions. Qualitative ultrastructural differences were not observed between strains, but engorged macrophages of the dystrophic strain typically showed a predominance of lipid droplets with grey homogeneous material, crowded cytoplasmic organelles, and fewer primary lysosomes. Lipid analyses showed an 85% increase of total cellular lipids, a 486% increase of cholesteryl esters in neutral lipids, and increased 18:1 fatty acids in total lipids and the cholesteryl esters in cells from the Bio 14.6 strain. The etiology of the lipid excess has not been determined, but elevated chylomicrons and reduced alpha-lipoprotein values were observed in the serum of the dystrophic strain.

Male Fisher 344 rats were solely fed a choline-supplemented diet for 65 to 105 weeks or a choline-devoid diet for 24 to 102 weeks. Hepatocellular carcinomas developed in the latter animals, beginning at 24 weeks. Other groups of rats were given a single dose of 20 mg diethylnitrosamine/kg, 18 h after a partial hepatectomy and were fed, 4 weeks thereafter, either a choline-supplemented, or a choline-devoid diet for up to 48 weeks. In rats fed the choline-supplemented diet, the only relevant lesion observed was a small transect number of foci of enzyme-altered hepatocytes. On the other hand, a significant number of foci, of preneoplastic nodules, and of hepatocellular tumors developed in rats fed the choline-devoid diet. The results obtained are consistent with those previously reported by others, indicating that diets devoid of choline, or of choline and methionine, are carcinogenic. The diets appear to act as complete carcinogens, since they are also efficient promoters of chemical hepatocarcinogenesis, as shown again, in the present study, by the results obtained in the diethylnitrosamine-pretreated rats.

Partially hydrogenated herring oils induce a cardiac lipidosis after a few days of feeding in the Rat. The level of C 22 : 1 in the oil, its chemical structure (erucic acid or isomers) as well as the presence of linoleic acid seem to have an effect upon the intensity of the phenomenon.

A morphometric study of atherosclerotic lesions of the vessels was conducted in males dying of cancer of the stomach and lungs, and in females dying of cancer of the stomach, lungs, uterus, breast and ovaries. In total, 918 observations were studied, the age of the deceased ranging from 30 to 79 years. The severity of the atherosclerotic lesions in the vessels of those who died of malignant tumors was compared to that in normal individuals. The material was compiled and examined in accordance with the program and method developed by WHO expertpathologists (Uemura et al.). In those who died of cancer of the stomach, uterus and breast the severity of coronary atherosclerosis was much milder than in the normals; however, no important differences were revealed between these groups as to the severity of atherosclerosis of the aorta. In lung cancer in males and in ovarian cancer in females under 50 years of age a distinct enhancement of the atherosclerotic process in the aorta was observed, and less-in the coronaries. In females dying of lung cancer the severity of atherosclerosis of the aorta was the same as in the normals, and in the coronaries - even milder.

Experiments were conducted to determine if regression of cardiac lipidosis and strain or sex differences in susceptibility to cardiopathological change induced by rapeseed oils are coincident with physiological differences in fatty acid substrates supplied to the heart. Plasma fatty acid composition was determined in male Sprague-Dawley rats after 7 or 28 days and in female Sprague-Dawley and male Chester-Beatty rats after 28 days of feeding high or low erucic acid rapeseed oils, soybean oil or peanut oil. After 28 days, C14:0 and C18:1 fell and C20:4 increased as a percent of total fatty acid in all animals irrespective of oil fed, suggesting that changes in plasma fatty acids normally occur with development. Saturated and essential fatty acid profiles of male and female rats were different. Differences in plasma fatty acids stemming from sex-related physiological differences in whole body fat metabolism may form the basis of lower cardiopathological involvement for females. Results suggest physiological differences unrelated to plasma fatty acids determine strain differences in timing and severity of rapeseed oil-induced cardiac pathology.