Capillary and aortic endothelia interact in situ with nonenzymatically glycated albumin and develop specific alterations in early experimental diabetes

Diabetic mice (6 weeks duration) were studied to assess the interaction of advanced glycation endproduct-modifed albumin (AGE-Alb) with micro- and macrovascular endothelium, and to evaluate the alterations induced in the ultrastructure of the lung, kidney, and aorta. [¹²⁵I]-AGE-Alb and AGE-Alb-Au were perfused in situ in the vasculature; the total uptake was quantitated by spectrometry, and the endothelial pathways of AGE-Alb-Au and the morphological alterations of the vascular beds were examined by electron microscopy. The results showed that [¹²⁵I]-AGE-Alb (0.567 μM) was taken up specifically and saturably by all organs studied, and particularly by the lung. AGE-Alb-Au endocytosis and transcytosis occurred in the pulmonary and aortic endothelia, and were enhanced in diabetic animals. Also in diabetic animals, AGE-Alb-Au was detected throughout the kidney glomerular basement membrane (GBM) and within open filtration slits of podocytes, suggesting altered barrier function. The structural modifications progressed, and at the end of the experimental period, in the lung ∼28% of the capillaries and ∼25% of the alveoli became compressed or even collapsed, due to the hyperplasia of extracellular matrix and interstitial connective tissue. The presence of adherent intravascular macrophages suggests the development of an inflammatory immune process. The structural modifications observed in kidney glomeruli included thickening (∼30%) of the GBM and the disappearance of diaphragms between the cellular processes of podocytes. The aortic endothelium displayed luminal foldings, increased number (2.8-fold) of Weibel-Palade bodies, and proliferation of basal lamina. Together, the results show that in diabetes there is enhanced vascular uptake of AGE-Alb and significant pathomorphological changes of micro- and macrovessels. Received: 28 June 1996 / Accepted in revised form: 8 May 1997     

Bone and Ceramic Interaction in the Bone Union Process

This study applied an experimental rat model and ceramic as an artificial matrix to explore the ultrastructural development of new bone production in tibia defects. By X-ray diffraction control or energy-dispersive X-ray analysis the nature of ceramic was verified and routine histology and TEM investigation were used to demonstrate bone - ceramic interaction. The results show that biphasic ceramic can promote bone growth in an osseous defect and is therefore an alternative to autogenous bone matrix. The porousity and bioactivity of the biphasic ceramic enhanced bone formation and provided a scaffold for new lamellar bone invasion.     

Image Quality in Real-Time Teleultrasound of Infant Hip Exam Over Low-Bandwidth Internet Links: a Transatlantic Feasibility Study

Evolution of communication systems, especially internet-based technologies, has probably affected Radiology more than any other medical specialty. Tremendous increase in internet bandwidth has enabled a true revolution in image transmission and easy remote viewing of the static images and real-time video stream. Previous reports of real-time telesonography, such as the ones developed for emergency situations and humanitarian work, rely on high compressions of images utilized by remote sonologist to guide and supervise the unexperienced examiner. We believe that remote sonology could be also utilized in teleultrasound exam of infant hip. We tested feasibility of a low-cost teleultrasound system for infant hip and performed data analysis on the transmitted and original images. Transmission of data was accomplished with Remote Ultrasound (RU), a software package specifically designed for teleultrasound transmission through limited internet bandwidth. While image analysis of image pairs revealed statistically significant loss of information, panel evaluation failed to recognize any clinical difference between the original saved and transmitted still images.     

Complete genome sequences of infectious spleen and kidney necrosis virus isolated from farmed albino rainbow sharks Epalzeorhynchos frenatum in the United States

Virus Genes - The genus Megalocytivirus includes viruses known to cause significant disease in aquacultured fish stocks. Herein, we report the complete genome sequences of two megalocytiviruses...     

The peridural membrane of the spine has characteristics of synovium

The peridural membrane (PDM) is a well-defined structure between dura mater and the wall of the spinal canal. The spine may be viewed as a multi-segmented joint, with the epidural cavity and neural foramina as joint spaces and PDM as synovial lining. The objective of this investigation was to determine if PDM has histological characteristics of synovium. Samples of the PDM of the thoraco-lumbar spine were taken from 23 human cadavers and analyzed with conventional light microscopy and confocal microscopy. Results were compared to reports on similar analyses of synovium in the literature. Histological distribution of areolar, fibrous, and adipose connective tissue in PDM was similar to synovium. The PDM has an intima and sub-intima. No basement membrane was identified. CD68, a marker for macrophage-like-synoviocytes, and CD55, a marker for fibroblast-like synoviocytes, were seen in the lining and sub-lining of the PDM. Multifunctional hyaluronan receptor CD44 and hyaluronic acid synthetase 2 marker HAS2 were abundantly present throughout the membrane. Marked presence of CD44, CD55, and HAS2 in the well-developed tunica muscularis of blood vessels and in the body of the PDM suggests a role in the maintenance and lubrication of the epidural cavity and neural foramina. Presence of CD68, CD55, and CD44 suggests a scavenging function and a role in the inflammatory response to noxious stimuli. Thus, the human PDM has histological and immunohistochemical characteristics of synovium. This suggests that the PDM may be important for the homeostasis of the flexible spine and the neural structures it contains.     

Facile Synthesis of Well‐Defined Telechelic Alkyne‐Terminated Polystyrene in Polar Media Using ATRP With Mixed Fe/Cu Transition Metal Catalyst

The synthesis of polystyrene (PS) by atom transfer radical polymerization using the Fe(0)/CuBr₂ catalytic system in dimethylformamide is reported. The effects of temperature, ligand, initiator structure, and monomer to solvent ratio on the polymerization kinetics are evaluated. PS with high molecular weight, low polydispersity, and telechelic structure are achieved and successfully used for further reinitiation or the copper(I)‐catalyzed Huisgen 1,3‐dipolar cycloaddition click reaction between alkyne‐ and azide‐terminated PS. For the first time, suitable styrene polymerization rates are achieved using this cost‐effective and environmentally attractive catalytic system. This method can be very useful in macromolecular engineering to afford PS‐based materials with well‐controlled structure.     

Plasma apolipoprotein concentrations in familial apolipoprotein A-I and A-II deficiency (Tangier disease)

Familial apolipoprotein A-I and A-II deficiency (Tangier disease) is characterized by cholesterol ester deposition in histiocytes, decreased plasma cholesterol and low density lipoprotein cholesterol (C-LDL), and a striking deficiency of high density lipoproteins (HDL). We measured plasma lipid, lipoprotein cholesterol, and plasma apolipoprotein (apo) A-I, A-II, B, C-I, C-II, C-III, D, and E concentrations in 7 Tangier homozygotes, 2 obligate heterozygotes, and 50 normal subjects. Heterozygotes had modest reductions in high density lipoprotein cholesterol (C-HDL), plasma apoA-I, and apoA-II levels. Mean concentrations (±SD) of plasma C-HDL and apolipoproteins A-I, A-II, B, C-I, C-II, C-III, D, and E in mg% in normals were: 50 ± 14, 134 ± 24, 68 ± 18, 98 ± 20, 7 ± 2, 3.7 ± 2, 13 ± 5, 10 ± 4, and 10 ± 4, respectively; and in homozygotes were: 1 ± 1, 1.3 ± 0.7, 4.8 ± 2.5, 82.6 ± 18, 4.1 ± 1.7, 2.3 ± 0.9, 6.5 ± 3.8, 2.2 ± 0.5, and 5.4 ± 3.1, respectively. Homozygotes had C-HDL, apoA-I and apoA-II levels which were 2%, 1%, and 7% (p < .001) of normal, respectively, and mean levels of apolipoproteins B, C-I, C-II, C-III, D, and E which were 84%, 59%, 62%, 50%, 22%, and 54% of normal, respectively. There was heterogeneity of these latter apolipoprotein concentrations among homozygotes. Mean apoC-I, apoC-III, apoD, and apoE levels were significantly less than normal (pp < .05) in homozygotes. These data indicate that homozygotes have variable but generally decreased apoC and apoE levels, a deficiency of apoD, and a striking reduction in plasma apoA-I and apoA-II concentrations.     

Specifics of Helicobacter pylori infection/NSAID effects in the elderly

The prevalence of Helicobacter pylori (HP) infection increases with age worldwide. Unlike in younger patients, the presentation of peptic disease in the elderly population is subtle and atypical, and thus leads to a delay of diagnosis. Due to comorbidities and advanced age, it results in increased complications, morbidity and mortality. Bleeding and perforation are frequent complications and therefore peptic ulcer in adult patients represents a serious disease. The relationship between the infection caused by HP and the use of non-steroidal anti-inflammatory drugs (NSAID) in the pathogenesis of peptic ulcer disease is still controversial. However these two factors, independently or in synergy, represent the principal cause of peptic ulcer development in the adult population. In patients diagnosed with peptic ulcer caused by HP, more than half take medications containing aminosalicylic acid. Helicobacter pylori infection in elderly NSAID users is associated with an increased ulcer incidence, but not with an increased prevalence of upper digestive tract bleeding. Helicobacter pylori and NSAID consumption are independent and unrelated risk factors for upper gastrointestinal tract bleeding. Eradication of HP is recommended before the initiation of a long-term aspirin administration in elderly patients. Low aspirin dosages are associated with a high risk of ulcer bleeding. The risk of upper gastrointestinal bleeding in elderly patients is significantly higher in the cases of acute abuse of NSAIDs relative to its chronic use. The simultaneous use of NSAID or aspirin and selective serotonin reuptake inhibitors--antidepressants, increases the risk of upper gastrointestinal bleeding. Peptic ulcer disease in the adult population, if combined with old age, presence of serious and/or life- threatening diseases, as well as repeated ulcer bleedings, shows a high mortality rate.