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PubMed1995

Left ventricular fibrosis in renovascular hypertensive rats. Effect of losartan and spironolactone.

Myocardial fibrosis resulting from arterial hypertension alters myocardial structure and function. Myocardial fibrosis is characterized by a pathological accumulation of types I and III collagens. We used an aldosterone antagonist (spironolactone) and an angiotensin II antagonist (losartan) to elucidate the respective role of these hormones and hypertension in the development of myocardial fibrosis in the Goldblatt model of two-kidney, one clip hypertension in the rat. Fibrosis was assessed by computer-assisted morphometry in the interstitial space, around coronary arteries, in microscar areas, and on left ventricular sections stained with Sirius red and by biochemical techniques. Morphometry was performed with both standard light and polarization microscopy; this latter method was used to quantify yellow-red and green collagen fibers. Concurrently, type I and type III collagen mRNAs were evaluated by a semiquantitative polymerase chain reaction method. The collagen content of the untreated two-kidney, one clip hypertensive rats increased mainly around the coronary arteries; the number and surface area of microscars also increased in chronic hypertension. Losartan treatment decreased systolic pressure and yellow-red collagen fiber content in all areas, whereas spironolactone treatment decreased green collagen fiber content without decreasing systolic pressure. mRNA levels for types I and III collagens showed profiles similar to those of yellow-red and green collagen fiber contents, respectively, suggesting that yellow-red collagen fibers are mainly type I collagen fibers and green collagen fibers are mainly type III collagen fibers. These results suggest that angiotensin II, possibly together with hypertension, and aldosterone, independently of hypertension, have a major influence on myocardial fibrosis, inducing type I and type III collagen deposits, respectively, mainly around coronary arteries.

Angiotensin II↗
PubMed2005

The crystal structure and physicochemical characteristics of 2-hydroxy-N-[3(5)-pyrazolyl]-1,4-naphthoquinone-4-imine, a new antitrypanosomal compound.

This study was designed to investigate the physical characteristics and crystalline structure of 2-hydroxy-N-[3(5)-pyrazolyl]-1,4-naphthoquinone-4-imine (PNQ), a new active compound against Trypanosoma cruzi, the causative agent of American trypanosomiasis. Methods used included differential scanning calorimetry, thermogravimetry, hot stage microscopy, polarized light microscopy (PLM), Fourier-transform infrared (FTIR) spectroscopy, and high-resolution X-ray powder diffraction (HR-XRPD). According to PLM and HR-XRPD data, PNQ crystallized as red oolitic crystals (absolute methanol) or prisms (dimethyl sulfoxide [DMSO]-water) with the same internal structure. The findings obtained with HR-XRPD data (applying molecular location methods) showed a monoclinic unit cell [a = 18.4437(1) A, b = 3.9968(2) A, c = 14.5304(1) A, alpha = 90 degrees , beta = 102.71(6) degrees , gamma = 90 degrees , V = 1044.9(1) A(3), Z = 4, space group P2(1)/c], and a crystal structure (excluding H-positions) described by parallel layers in the direction of the b-axis, with molecules held by homochemical (phenyl-phenyl and pyrazole-pyrazole) van der Waals interactions. In addition, FTIR spectra displayed the NH-pyrazole stretch overlapped with the OH absorption at 3222 cm(-1), typical of -NH and -OH groups associated through H-bondings; and a carbonyl stretching absorption at 1694 cm(-1), indicating a nonextensively H-bonded quinonic C=O, which was in accordance with the solved crystal structure of PNQ. The existence of such cohesive forces shed light on the thermoanalytical data, which revealed that PNQ is a stable solid, unaffected by oxygen that decomposed without melting above 260 degrees C.

Antiprotozoal Agents↗
PubMed2002

[A trial production of a table of the optical crystallographic characteristics of crystalline drugs including crystal habits (study of crystalline drugs by means of a polarizing microscope. XIX].

It was clarified in previous report that the predominant faces of crystal habits mainly coincide with the morphologic crystal face at (001), (010), or (100), and therefore the two measurable key refractive indices are closely related to the principal sections of the two axial wave surfaces and coincide with the one or two of the three principal refractive indices. The three principal refractive indices of biaxial crystalline drugs were measured and tabulated in the "General Information" section of the National Formulary compiled by the American Pharmaceutical Association. A series of studies was conducted to measure the key refractive indices of the crystalline drugs listed in the Japanese Pharmacopoeia X or XI so that the data could be used to improve the quantitative analysis of their crystal habits. The purpose of the present study was to examine data on both the key and principal refractive indices and attempt to produce a general authorized table of optic crystallographic characteristics, including crystal habits, for simpler and more reliable polarizing microscopy studies.

Crystallization↗
PubMed1996

Brittle and sparse hair with normal cystine content caused by methionine deficiency?

The unusual case of an 8-year-old girl with a hair disorder is presented, characterized by brittle, short and sparse hair. On polarizing microscopy the latter reveals a "tiger tail" pattern, whereas severe cuticular defects are detected on scanning electron microscopy. The patient's hair has a normal cystine content but is completely devoid of methionine and reveals distinct changes of its visoelastic parameters. It is presently unknown whether the lack of methionine may be implicated in the pathogenesis of this hair disorder, which to the best of our knowledge has not been previously described.

Child↗
PubMed1994

Expression of the MAS proto-oncogene in the retinal pigment epithelium of the rhesus macaque.

The MAS proto-oncogene codes for a seven transmembrane protein which has been previously localized to specific regions of the hippocampus and cerebral cortex in the rat central nervous system. Because MAS has biological properties related to the growth and differentiation of cells of neuroectodermal origin, we investigated the distribution of MAS expression in the rhesus macaque retina by in situ hybridization. A 330 base pair (bp) segment of the human MAS sequence was subcloned and used to generate single-stranded cRNA probes for these studies. Our results demonstrated little, if any, positive signal over the neurons of the retina. The use of epi-polarization microscopy, however, revealed a distinct positive labelling of retinal pigment epithelial (RPE) cells. These studies suggest the use of MAS as a possible marker for the retinal pigment epithelium.

Animals↗
PubMed1991

Crush and smear technique for rapid detection and semiquantitation of amyloid deposition.

A method using Congo red to rapidly identify and semiquantitate amyloid deposits in tissues for experimental research and clinical medicine is described. Examination by polarization microscopy revealed amyloid deposits as bright green birefringent clumps on a dark red background. On semiquantitative evaluation, good correlation was found between this technique and the conventional histological one, the present technique being more sensitive. The method described saves time and expense.

Amyloid↗
PubMed2005

Thermal and structural behavior of anhydrous milk fat. 3. Influence of cooling rate.

The crystallization behavior of anhydrous milk fat has been examined with a new instrument coupling time-resolved synchrotron x-ray diffraction as a function of temperature (XRDT) at both small and wide angles and high-sensitivity differential scanning calorimetry. Crystallizations were monitored at cooling rates of 3 and 1 degrees C/ min from 60 to -10 degrees C to determine the triacylglycerol organizations formed. Simultaneous thermal analysis permitted the correlation of the formation/melting of the different crystalline species monitored by XRDT to the thermal events recorded by differential scanning calorimetry. At intermediate cooling rates, milk fat triacylglycerols sequentially crystallize in 3 different lamellar structures with double-chain length of 46 and 38.5 A and a triple-chain length of 72 A stackings of alpha type, which are correlated to 2 exothermic peaks at 17.2 and 13.7 degrees C, respectively. A time-dependent slow sub-alpha <--> alpha reversible transition is observed at -10 degrees C. Subsequent heating at 2 degrees C/min has shown numerous structural rearrangements of the alpha varieties into a single beta' form before final melting. This polymorphic evolution on heating, as well as the final melting point observed (approximately 39 degrees C), confirmed that cooling at 3 degrees C/min leads to the formation of crystalline varieties that are not at equilibrium. An overall comparison of the thermal and structural properties of the crystalline species formed as a function of the cooling rate and stabilization time is presented. The influence on crystal size of the cooling rates applied in situ using temperature-controlled polarized microscopy is also determined for comparison.

Animals↗
PubMed2000

An evaluation of methods for the detection of spinal cord in product derived from advanced meat recovery systems.

This study investigated the usefulness of immunohistochemistry, histochemistry, and polarization microscopy in documenting the presence of spinal cord in ground product produced by advanced meat recovery systems (AMRS). A battery of diagnostic stains proved most helpful for definitive documentation of spinal cord in the AMRS product. Antibodies to neurofilament and glial fibrillary acidic proteins were useful for highlighting the presence of neural tissue in comminuted product but when used alone did not definitively differentiate central nervous system tissue from peripheral nerve. Polariscopy, trichrome staining, and immunostaining for synaptophysin were very useful for differentiating spinal cord from peripheral nerve. Spinal cord was found in 2 of 196 AMRS samples when only hematoxylin and eosin staining was used. In a later immunohistochemical subset of the survey study, spinal cord was found in 7 of 17 AMRS samples. More recently, spinal cord tissue has been found in 3 of 26 regulatory samples using hematoxylin and eosin stains combined with immunohistochemical techniques.

Animals↗
PubMed1999

[Microscopic study of dental calculus in cadavers from the 18th-19th centuries].

The authors studied the dental calculus of 20 mummies with ligth microscopy, polarized ligth microscopy and scanning electron microscopy. Gram positive bacteria could be detected in all preparates, while Gram negative bacteria in 12 and fungi only in 3 dental calculus was visible. Animal food remains within five, and plant remains in all dental calculus were identified. Anorgic element and cell debris were seen in all preparates.

Adult↗
PubMed1975

[Report of case of opalescent dentin. A polariation optic and microradiographic study on a pulpless tooth].

Ground sections prepared from a molar (-7) with opalescent dentine were investigated by the means of polarizing microscopy and microradiography. Histological and clinical findings are discussed. Unfortunately, heredity could not be surely determined. But in all experience we are shure, that a hereditary mutation, recently or earlier in a generation occured, was the cause also in this case.

Adult↗
PubMedDate not supplied

[Morphological sign of cardiac ventricle fibrillation].

An early sign of cardiac ventricle fibrillation is described: numerous surface cracks in the myocardial fibers. The formation of cracks is the initial stage of myocardial fiber fragmentation. The cracks are detected by polarization microscopy in the absence of fragmentation or in myocardial sites without focal fragmentation.

Cause of Death↗
PubMed1975

[The scientific work of W. J. Schmidt (author's transl)].

Ten examples from W. J. Schmidt's workshop illustrate the method of ultrastructural research before the advent of the electron microscope. The consistency is shown with which the research worker W. J. Schmidt pursued his goal, how he succeeded in making fundamental discoveries with his polarizing microscope, and interpreted the results of his indirect structural investigations in such a forward-looking and clearsighted manner that many of them were confirmed by direct reproduction in the electron microscope. This makes W. J. Schmidt one of the great pioneers of ultramicroscopic structural research. He was an extremely prolific writer. His list of publications numbers 404 scientific contributions, three classical books among them. The last of these three monographs was written in 1971; its title is "Polarizing Microscopy in Dental Tissues"; it deals with the ultrastructure of teeth, a subject which never ceased to attract his attention during the more than 50 years of his career as a scientist. It was his intention to write such a textbook on the ultrastructure of teeth during his retirement, a task which he accomplished in spite of the infirmities of old age, thanks to his unbroken will to work. Another characteristic feature of W. J. Schmidt was his extraordinary insistence on complete independence; there are only four among his 404 publications which he wrote, at an advanced age, jointly with Helmut Ruska, and the dental monograph he published in callaboration with A. Keil. Everything else was entirely his own effort. His capacity for work was almost inexhaustible. In 1937, for instance, he published 18 scientific papers, among them his richly illustrated protoplasm monograph of 388 pages. His inflexible will to observe everything personally and to interpret and edit his findings alone was part of his special intellectual constitution. In discussions he stubbornly defended his point view and considered suggestions and new ideas only after he had tested them with his own experiments. This had already become evident at the beginning of his career in a discussion with Ambronn of the nature of birefringence of organized substances. But once he had accepted something as proved he propounded it with persistence and enthusiasm.

Cell Biology↗
PubMed2001

Histological techniques and microscopic analysis of biological agents for preservation of human bone remains.

Microscopy and histology techniques can be applied to morphological study of fungi and bacteria contaminating ancient human osteological remains. Undecalcified samples are cut with a diamond rotary blade microtome and an original technique was applied using adhesive tape to prevent damage to the bone surface during sectioning. We used light microscopy, polarized light microscopy, and epi-illumination fluorescence systems. Common dyes can be applied to 80 microm sections using classic staining techniques to reveal the architecture of bone and the presence of infecting biological agents.

Bone and Bones↗
PubMed1999

[The amyloidosis in cardiac conduction system].

OBJECTIVE: To investigate the relationship between arrhythmia, cardiac failure and amyloidosis of cardiac conduction system (CCS). METHODS: CCS from 6 cases with cardiac amyloidosis were sampled using technique designed by the authors. The CCS were studied by Congo red staining and polarization microscopy. RESULTS: Pathological changes could be found in the CCS of these 6 cases. It was serious in sino-atrial node while slight in atrio-ventricular conduction system. The changes in atrio-ventricular conduction system were exacerbated from proximal part (atrio-ventricular node) to distal part (left bundle branch). In the 3 cases with sinus bradycardia and conduction blocking manifested by electrocardiogram, the pathological changes in CCS were more extensive and serious than that of other cases. CONCLUSION: The amyloidosis in CCS is one of the pathological bases of arrhythmia.

Aged↗
PubMed2002

[The crystal-optic method as an objective criterion for assessment of the course of the wound process in parturient women].

The structure was studied of biological media (blood, wound exudation, biopsy specimen from the wound) in 119 parturient women presenting with suppurating wounds to diagnose the course of the wound process, using the method of polarization microscopy. The biological material was taken before the treatment, during its course, and after the treatments administered. Based on the studies made the authors have come to the conclusion that the crystallooptic method reflects the bodily state of the women in labour validating the pathogenesis of the pyoinflammatory diseases; it is helpful in following the change of phases of the wound process, showing efficiency of treating purulent wounds, rejuvenation of tissues in the wound toward their primary functional state.

Biopsy↗
PubMed2003

Nonceramic hydroxyapatite bone derivative in sinus augmentation procedures: clinical and histomorphometric observations in 10 consecutive cases.

A synthetic, nonceramic resorbable hydroxyapatite (R-HA) was applied to augment the subantral area in 10 consecutive sinus lift procedures in humans. Implants were simultaneously placed in eight patients; in the remaining two, where residual bone height was less than 3 mm, a two-stage surgical approach was carried out. The aim of the study was to examine, clinically and histopathologically at 12 months, the healing pattern of these augmented sinuses around the implants. In the simultaneous technique, radiopaque grafted mineral surrounded the implants. In the two-stage technique, R-HA particles filled the augmented site and were confined to the subantral area. At the uncovering phase, all implants (n = 36) were stable, with no clinical bone resorption around the cervix. A 2.5-mm trephine bur was used to collect specimens from the 10 augmented sites at the lateral-deep area. Histologically, new bone formation was evident in all examined cores. R-HA particles were primarily surrounded by newly formed bone, mostly woven bone, in different stages of remodeling. However, in the deep areas of the specimen cores, lamellar bone fragments were also seen. Morphometric measurements showed that the mean bone area of the 10 sites was 28.1% at the lateral/external side and 37.8% at the deep/inward side. Under polarizing microscopy, the mean lamellar:woven bone ratio was 1:7.2 at the lateral side and 1:4.2 at the deep end. Differences were statistically significant. R-HA proved to be a suitable filler material for osseointegrated implants in sinus augmentation procedures, since it showed both biocompatible and osteoconductive properties.

Adult↗
PubMed1992

Subcutaneous bursitis in scleroderma.

We encountered 3 types of subcutaneous bursitis in our patients with scleroderma: dry bursitis characterized by a rub, sterile bursitis characterized by inflammatory effusions without crystals by polarizing microscopy, and septic (staphylococcal) subcutaneous bursitis. The latter, which occurred in 6 of 40 consecutive patients, had a protracted course, was often complicated by fistulas, and tended to involve several bursae particularly in patients with extensive calcinosis.

Adult↗