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Stroke-prone spontaneously hypertensive rats as an experimental model of malignant hypertension. I. A light- and electron-microscopic study of the brain.

A pathological study of the brain of the stroke-prone spontaneously hypertensive (SHRSP) rats revealed development of fibrinoid necrosis of … ions, and are assumed to have minor contribution to the brain swelling. Widespread expansion of the extracellular space is assumed to be responsible for the brain swelling. Overall vascular changes of the brain, kidney, and other organs were consistent with those found in malignant hypertension.

Вирусный гепатит Ласса. Замечания в отношении смертельного случая эпидемии в Сьерра-Леоне 1972 года.

Во время недавней вспышки лихорадки Ласса в Сьерре-Леоне 20-летняя женщина заразилась острым фебриальным заболеванием, в результате которого были вырваны геморрагические ощущения. Вирус Ласса был изолирован в клеточных культурах от харинговых секреций и плевральной жидкости и был идентифицирован посредством дополнительной фиксации. Типичные частицы арены наблюдались в этих инфицированных клеточных культурах. В биопсии печени были обнаружены диффузные повреждения гепатоклеточной клетки и фокусные некрозы с спектром изменений клеток печени, от легкого вакуолизаитона до откровенного лиза. Вирус ч

Совпадение в аннотации оригинала
During a recent outbreak of Lassa fever in Sierre Leone, a 20-year-old woman developed an acute febrile disease with tonsillar exudates and … l change, ranging from slight vacuolizaiton to frank lysis. Virus was frequently observed in nearby extracellular spaces and was clearly associated with hepatocytes rather than sinusoidal cells. The demonstration for the first time of Lassa virus particules in human tissue provides direct evidence that the virus is responsible for the observed pathologic changes.

On the ultrastructure of epithelial cells in bile ducts of cattle chronically infected with fasciola hepatica.

This paper describes briefly the normal ultrastructure of bile-duct epithelial cells in cattle and the main ultrastructural alterations produced in them by chronic infection with Fasciola hepatica. The studies showed only inconsiderable abnormalities in the ultrastructure of the epithelium in infections of a low degree as also during the recovery phase of the disease. On the other hand, in heavily infected livers pronounced ultrastructural alterations were seen in the surface epithelium of the main intrahepatic bile ducts invaded by the flukes. In such areas the intercellular spaces were fille

[The ultrastructural features of sputum deposition and its value in the diagnosis of pulmonary alveolar proteinosis].

OBJECTIVE: To investigate the ultrastructural features of sputum deposition (SD) and its value in the diagnosis of pulmonary alveolar protei … in alveolar epithelial cells, and lots of lamellar bodies in the shape of concentric circle in the extracellular spaces. Four from the 7 SD samples were consistent with the diagnosis of PAP. No significant difference was found between SD and BALF in the diagnosis of PAP by electronic examination (P > 0.05). In the 7 cases of control group no drifting osmiophilic lam …

Analysis of K+ accumulation reveals privileged extracellular region in the vicinity of glial cells in situ.

Astrocytes and oligodendrocytes in rat and mouse spinal cord slices, characterized by passive membrane currents during de- and hyperpolarizi … K+ into the cell. In the present study, we used a mathematical model to calculate the volume of the extracellular space (ECS) in the vicinity of astrocytes and oligodendrocytes (ESVv), defined as the volume available for K+ accumulation during membrane depolarization. A mathematical analysis of membrane currents revealed no differences between glial cells from mouse …

Functional Inclusion of RNA Biology in the Tethered Extracellular Matrix.

RNA biology is traditionally confined to the cytosolic and nuclear spaces, where it plays critical roles across nearly all biochemical processes. Our recent observation of spatiotemporal regulation of cell surface ribonucleoproteins, consisting of glycoRNA and RNA-binding proteins, by heparan sulfate expands this knowledge to the extracellular matrix (ECM). We identified VEGF-A as a new noncanonical cell surface RNA-binding protein through the arginine residues within the heparan sulfate binding domain. The interaction between VEGF-A and cell surface RNA as a polyanion in the ECM provides an e

Role of Sensory Nerves in Pulmonary Fibrosis.

Pulmonary fibrosis results from the deposition and proliferation of extracellular matrix components in the lungs. Despite being an airway disorder, pulmonary fibrosis also has notable effects on the pulmonary vasculature, with the development and severity of pulmonary hypertension tied closely to patient mortality. Furthermore, the anatomical proximity of blood vessels, the alveolar epithelium, lymphatic tissue, and airway spaces highlights the need to identify shared pathogenic mechanisms and pleiotropic signaling across various cell types. Sensory nerves and their transmitters have a variety

Diagnostic Tools for Cardiac Amyloidosis: A Pragmatic Comparison of Pathology, Imaging and Laboratories.

Cardiac amyloidosis (CA) is a complex disease considered to be the most common underdiagnosed form of restrictive cardiomyopathy. Accumulation of misfolded proteins called amyloid fibrils in the extracellular space results in clinical deterioration and late diagnosis is associated with morbidity and mortality. Both types of this disease, light chain CA and transthyretin-related CA share many cardiac and extracardiac features that compromise multiple organs such as kidneys, musculoskeletal system, autonomic nervous system, and gastrointestinal tract. Early diagnosis and detection of CA are impe…

Intercellular Spread of Protein Aggregates in Neurodegenerative Disease.

Most neurodegenerative diseases are characterized by the accumulation of protein aggregates, some of which are toxic to cells. Mounting evidence demonstrates that in several diseases, protein aggregates can pass from neuron to neuron along connected networks, although the role of this spreading phenomenon in disease pathogenesis is not completely understood. Here we briefly review the molecular and histopathological features of protein aggregation in neurodegenerative disease, we summarize the evidence for release of proteins from donor cells into the extracellular space, and we highlight some…

Peptidoglycan editing by a specific LD-transpeptidase controls the muramidase-dependent secretion of typhoid toxin.

Protein secretion mechanisms are essential for the virulence of most bacterial pathogens. Typhoid toxin is an essential virulence factor for Salmonella Typhi, the cause of typhoid fever in humans. This toxin is unique in that it is only produced within mammalian cells, and it must be trafficked to the extracellular space before intoxicating target cells. An essential and poorly understood aspect of this transport pathway is the secretion of typhoid toxin from the bacterium into the S. Typhi-containing vacuole. We show here that typhoid toxin secretion requires its translocation to the trans si…

Biosynthesis of Astrocytic Trehalose Regulates Neuronal Arborization in Hippocampal Neurons.

Trehalose is a nonreducing disaccharide that has recently attracted much attention because of its ability to inhibit protein aggregation, in … ocampus. We found that primary astrocytes were able to synthesize trehalose and release it into the extracellular space. Notably, the TreH enzyme was observed only in the soma of neurons, which are the exclusive users of this substrate. A statistical analysis of the metabolome during different stages of maturation indicated that this metabolite is implicated in neuro …

Non-coding RNAs as modulators of the cardiac fibroblast phenotype.

Cardiac fibroblasts represent one of the most frequent cell type in the heart of rodents and humans and alterations of their phenotype have a great impact on cardiac function. Due to aging, ischemic injuries, valvular dysfunctions, hypertension and aortic stenosis, multiple signals trigger the accumulation of extracellular matrix in the cardiac interstitium and perivascular space, leading to structural and functional detrimental changes in the heart. Cardiac fibroblasts are the principal orchestrators of matrix formation and degradation and indirectly regulate cardiac hypertrophy and inflammat

New drugs for the treatment of hyperkalemia in patients treated with renin-angiotensin-aldosterone system inhibitors -- hype or hope?

Hyperkalemia (serum potassium >5.5 mmol/L) may result from increased potassium intake, impaired distribution between the intracellular and extracellular spaces, and/or reduced renal excretion. Renin-angiotensin-aldosterone system inhibitors (RAASIs) represent an important therapeutic strategy in patients with hypertension, heart failure, chronic kidney disease, and diabetes, but hyperkalemia is a key limitation to fully titrate RAASIs in these patients who are most likely to benefit from treatment. Thus, we need new drugs to control hyperkalemia in these patients while maintaining the use of R…

A comparative analysis of body water compartments for Egyptian patients with Schistosoma mansoni infection.

In light of reports that schistosomiasis is associated with alterations in nutritional status, and considering that the assessment of body composition and water spaces is important for nutritional and hydration management, we conducted a study to evaluate the reproducibility of estimates of total body water, extracellular water, and intracellular water for Egyptians with Schistosoma mansoni infection using various bioelectric impedance analysis (BIA) formulae in comparison with reference values obtained using dilution techniques. The estimates obtained using the various formulae varied from th

Ultrastructural and immunohistochemical findings in five patients with vitreomacular traction syndrome.

OBJECTIVE: To evaluate pathologic features of vitreomacular traction syndrome (VMT). METHODS: Preretinal membranes removed from five patients during vitreous surgery for VMT syndrome were evaluated by electron microscopy (n = 4) and immunohistochemistry (n = 1). RESULTS: Electron microscopic examination revealed large segments of internal limiting lamina (ILL) in three of the four cases. Other extracellular features included two types of abnormal collagen fibrils, determined to be type I and fibrous long-spacing collagen. The myofibrocyte was the predominant cell type in all cases. Collagen

Fibrillin-rich microfibrils: an X-ray diffraction study of the fundamental axial periodicity.

Microfibrils are ubiquitous matrix polymers which are thought to provide elastic properties in all extracellular matrix structures. The major component of the elastic microfibrils is the protein fibrillin; its molecular structure is unknown. In electron microscopy, microfibrils appear as beaded structures exhibiting a variable periodicity, indicating that they may be elastomeric. The X-ray diffraction of fibrillin-rich microfibrils in the form of zonular filaments from bovine eyes exhibits meridional diffraction peaks indexing on a fundamental periodicity of 55 nm in the relaxed state. The app

CHARGE association with congenital glaucoma due to maldevelopment of the anterior chamber angle.

PURPOSE: We examined the clinicopathologic features of a male infant with the CHARGE association and bilateral congenital glaucoma. METHODS: Trabeculectomy specimens were obtained from the anterior chamber angle and examined by light and electron microscopy. RESULTS: Histopathologic examination of the trabeculectomy specimens showed immature development of the trabecular meshwork that was covered by the ciliary muscles. There were few intertrabecular spaces because the meshwork was almost completely filled with cells and extracellular substances. Deposition of a granular and/or homogeneous s

Effects of intracameral injection of chondroitinase ABC in vivo.

A glycosaminoglycan-degrading enzyme, chondroitinase ABC, was introduced into the anterior chamber of three cynomolgus monkeys. Following the injection, the intraocular pressure decreased in the experimental eyes. Depending on the monkey, the intraocular pressure was lowered for 5, 7, or 14 days before it returned to the normal level. Repeated injections produced a similar response. Structurally, the intertrabecular spaces appeared widened, and marked ballooning of the juxtacanalicular tissue was observed. The outer trabecular beams and the inner wall of Schlemm's canal were greatly disorganiz

[The Schwartz-Bartter syndrome].

Nine children with Schwartz-Bartter-syndrome are described. Seven suffered from severe diseases of the CNS, 2 developed the syndrome during treatment with vincristine, the damaging action of which on the CNS is known. The main symptoms of the syndrome are: hyponatremia with consecutive hypotonia of the extracellular space caused by excessive urinary sodium loss. The plasma volume is not diminished. Therapeutically administered NaCl appears in the urine which is hyperosmolar in spite of the hypoosmolarity of the plasma. The increased secretion of ADH which Schwartz et al. postulated to be the c…

Cortical cellular response in acute subarachnoid hemorrhage.

Acute subarachnoid hemorrhage (SAH) over the cerebral cortex causes single or multiple waves of cellular depolarization, which may occur in a self-propagating, reverberating fashion. This process is characterized by a massive K+ release and transient depression in electrocortical activity. The K+ levels in the extracellular space reach magnitudes known to substantially affect the membrane potentials of neurons and glia, and may cause a release of neurotransmitters from depolarized presynaptic terminals. The release of K+ may be the initial step in the development of cellular edema and, togethe…