Resveratrol Protects Cardiac Tissue in Experimental Malignant Hypertension Due to Antioxidant, Anti-Inflammatory, and Anti-Apoptotic Properties

Hypertension is one of the most prevalent and powerful contributors of cardiovascular diseases. Malignant hypertension is a relatively rare but extremely severe form of hypertension accompanied with heart, brain, and renal impairment. Resveratrol, a recently described grape-derived, polyphenolic antioxidant molecule, has been proposed as an effective agent in the prevention of cardiovascular diseases. This study was designed to examine chronic resveratrol administration on blood pressure, oxidative stress, and inflammation, with special emphasis on cardiac structure and function in two models of experimental hypertension. The experiments were performed in spontaneously (SHRs) and malignantly hypertensive rats (MHRs). The chronic administration of resveratrol significantly decreased blood pressure in both spontaneously and malignant hypertensive animals. The resveratrol treatment ameliorated morphological changes in the heart tissue. The immunohistochemistry of the heart tissue after resveratrol treatment showed that both TGF-β and Bax were not present in the myocytes of SHRs and were present mainly in the myocytes of MHRs. Resveratrol suppressed lipid peroxidation and significantly improved oxidative status and release of NO. These results suggest that resveratrol prevents hypertrophic and apoptotic consequences induced by high blood pressure with more pronounced effects in malignant hypertension.

Recrystallization in different sunscreen formulations after cutaneous application

BACKGROUND

Data on the structure of sunscreens prior to and after application to the skin and the possible impact of these factors on their efficacy are still scant.

AIMS

The microscopic structure of several commercial sunscreen products containing benzophenone-3 (BP-3) was analysed under a light microscope, prior to and 2 h after application of the products to the skin, and compared with various control preparations with or without BP-3.

METHODS

All tested formulations were mounted on microscope slides, viewed under a light microscope and photographed. Samples were taken directly from original packages or from freshly prepared prescription formulations. Two hours after application to the skin, the samples were taken and processed for microscopy.

RESULTS

In some commercial sunscreens numerous crystals were formed upon cutaneous application, whereas others contained crystals both prior to and after epicutaneous application. A single commercial product (a lamellar ambiphyl emulsion, SPF28) retained its regular structure throughout the study. Control preparations with or without BP-3 and/or octyl methoxycinnamate contained crystals after cutaneous application.

CONCLUSIONS

Ingredients, most probably BP-3, in many commercial sunscreens are prone to recrystallization while on the skin which might interfere with their UV light-absorbing function.

[Biomechanical characteristics of spinal cord tissue--basis for the development of modifications of the DREZ (dorsal root entry zone) operation]

Mechanical properties of the spinal cord tissue--biological basis for the development of the modality of the DREZ surgery lesioning technique Succesful treatment of the chronic neurogenic pain of spinal cord and cauda equina injury origin remains a significant management problem. The mechanism of this pain phenomenon has been shown to be related to neurochemical changes that lead to the state of hypereactivity of the second order dorsal horn neurons. The DREZ surgery (Dorsal Root Entry Zone lesion), designed to destroy anatomy structures involved in pain generating thus interrupting the neurogenic pain mechanism, as a causative procedure in treating this chronic pain, has been performed by using different technical modalities: Radiofrequency (RF) coagulation technic, Laser, Ultrasound and Microsurgical DREZotomy technic. The purpose of the study was to assess the possibility for the establishment of the lesioning technic based on the natural difference in the mechanical properties between the white and gray cord substance. We experimentally deteminated mechanical properties of the human cadaveric cord white versus gray tissue for the purpose of testing possibility of selective suction of the dorsal horn gray substance as a DREZ lesioning procedure. Based on the fact of the difference in tissue elasticity between white and gray cord substance we established a new and simple DREZ surgical lesioning technique that was tested on cadaver cord. For the purpose of testing and comparing the size and shape of the DREZ lesion axchieved the DREZ surgery has been performed on cadaver cord by employing selective dorsal horn suction as a lesioning method. After the procedure cadaver cord underwent histological fixation and analysis of the DREZ lesions achieved. Our result revealed that the white cord substance with longitudinal fiber structure had four time higher dynamical viscosity than gray substance of local neuronal network structure (150 PaS versus 37.5 PaS) that provided possibility for the safe and selective suction of the gray substance of the dorsal horn. Technic includes incision of the dorsolateral sulcus according to Sindous Microsurgical DREZotomy technic than suction under visual control of the dorsal horn gray matter using succer adopted from the lumbar puncture nidle. Operative experimental testing and hystological analysis confirmed expected size and shape of the DREZ lesion performed by dorsal horn suction as DREZ lesioning technique. The utility, selectivity and safety of this technic has been provided by the natural mechanical properties of the cord tissue itself. Application of the Dorsal horn suction as a DREZ lesioning in humans confirmed this technic as a safe and reliable DREZ lesioning method.

[Cytologic features of ameloblastoma]

Ameloblastoma is a rare tumor of the jaw arising from odontogenic epithelium. There are sparse reports in the literature concerning cytologic features of this tumor. This paper presents two cases of ameloblastoma, diagnosed by imprint cytology and confirmed histopathologically. The imprints were hypercellular, with single cells and the groups of basaloid and polygonal squamous cells with huge vacuoles in cytoplasm. Stellate and fusiform cells were found in the background of the preparation. These morphologic parameters were sufficient for the cytologic diagnosis of ameloblastoma.

[Diagnosis of the Mikulicz-Sjogren syndrome using biopsy of the minor salivary glands]

BACKGROUND

Sjögren's syndrome (SS) represents autoimmune disease characterized by chronic inflammation, destruction and insufficiency of exocrine glands, particularly salivary and lacrimal glands, accompanied by dryness of mouths and eyes. Diagnostic work-up involves clinical laboratory tests, radiography, scintigraphy and bioptic histopathological examination. Examination of small salivary glands in the biopsy of the lower lip represents a "golden standard" of diagnosis of SS, concerning the fact that the growth and the disfunction of salivary and lacrimal glands occurs in different pathologic states.

METHODS

Resected specimens of the lower lip were obtained from 47 patients with clinical diagnosis of SS. After standard histopathological treatment, slices were hematoxylin and eosin stained. Immunohistochemistry against smooth muscle actin was performed using LSAB+ method (AHSMA-M7558, DAKO 1:50). On the basis of generally accepted histopathological diagnostic criteria the results were categorized as: findings suspicious for SS; findings compatible with the diagnosis of SS (mild, moderate and high degree of inflammation); nonspecific inflammatory reaction and nonrepresentative biopsy samples.

RESULTS

Diagnosis of SS was confirmed in 32% of cases. In 2% of cases findings were suspected for SS, in 36% of cases findings were compatible with the diagnosis of nonspecific inflammation, and in 30% of cases material was not representative.

CONCLUSIONS

By the biopsy of salivary glands of the lower lip the diagnosis of SS was confirmed in 50-60% of cases. Upon the precise diagnostic criteria it was also possible to determine the intensity of inflammation and tissue destruction in SS and identify other pathological conditions, which justified the biopsy. Surgical technique had to be adequate in order to obtain representative number of small salivary glands. In the presented material 30% of specimens were nonrepresentative which was very high percentage compared with literature data. This was most probably the reason why the diagnosis of SS was confirmed in only 32% of cases, i.e., in every third patient.

Production of TNF-alpha by skin explants of dinitrochlorobenzene-challenged ears in rats: a model for the evaluation of contact hypersensitivity

BACKGROUND

Contact hypersensitivity (CHS) is a local inflammatory response of the skin following challenge of hapten-sensitized animals. It is the consequence of cell infiltration of derm and the release of inflammation mediators, among which Tumor necrosis factor-alpha (TNF-alpha) is one of the most important factors. The intensity of the inflammation could be quantified by ear swelling which is the classical manifestation of the reaction. This study was testing the working hypothesis that levels of TNF-alpha in skin organ culture medium should correlate with the intensity of CHS reaction measured in vivo by ear swelling assay, and with the density of dermal infiltrate in ear skin samples. In order to test the working hypothesis, the intensity of inflammatory reaction following challenge was evaluated by classical measurements of ear swelling, by the determination of TNF-alpha levels in culture fluids of ear skin following epicutaneous application of dinitrochlorobenzene (DNCB) into the ears of sensitized animals.

METHODS

Animal model of CHS reaction to DNCB in Albino Oxford rats was used as described. Ear swelling was quantified in percentage terms as the difference in thickness between the challenged and nontreated ears of the same animal. Dermal infiltrate density in histopathologically analyzed samples of ear skin was evaluated by computer-assisted image analysis. Ear skin samples were cultured in standard medium for 24 h, and TNF-alpha concentration in the conditioned medium was subsequently determined with ELISA test.

RESULTS

Dose-dependent increase in the density of the dermal infiltrate and in TNF-alpha in CM were noted following the application of 0.65%, 1.3% and 2.6% of DNCB to the ears of previously sensitized rats. The correlation between ear swelling and the levels of TNF-alpha (r = 0.933, p < 0.001) in CM, and between ear swelling and dermal infiltrate density (r = 0.916, p < 0.001) was found. Correlation was also found between the density of the dermal infiltrate and the levels of TNF-alpha (r = 0.865, p < 0.001).

CONCLUSION

Presented data suggested that skin-organ culture system and the quantification of inflammatory mediators might be used for the evaluation of contact hypersensitivity reaction and its intensity.

[Histochemical detection of primary shell residue mixture in the entry of gunshot wounds]

Alizarin red S, a commonly used organic dye in the histologic identification of calcium deposits, also forms colored reaction products with other metal ions, such as barium and lead, which are present in primer residue. The possibility was presented of using this histochemical technique in determination of firing distance based on the results in experimentally made close-range gunshot wounds (up to 1 m) by using several types of firearms.

Lupus nephritis: histopathologic features, classification and histologic scoring in renal biopsy

Lupus nephritis (LN) is one of the most significant manifestations in systemic lupus erythematosus (SLE), although in some cases there is no direct correlation among clinical, serologic and histologic findings. Therefore, renal biopsy and histopathologic classification by the activity and chronicity assessment of LN are considered necessary before the initiation of the treatment. In this paper 311 renal biopsies in patients with LN were analyzed and classified according to the WHO Classification published in 1974. Renal biopsy specimens were routinely processed for standard analysis by light microscopy (LM), immunofluorescent (IF), and electron microscopy (EM). Biopsy findings were compared with the common clinical symptoms. It is important to recognize that histopathologic lesions in the analyzed tissue might precede the symptoms and clinical manifestations, and therefore are an important factor in the appropriate therapeutic approach. Histopathological assessment of the class of LN represents an important predictor in most patients because the lesions of LN class I and class II most often have no progression and consequently do not require an aggressive treatment. Diffuse proliferative glomerulonephritis (class IV) as a severe form of renal lesion requires the application of high doses of corticosteroids and cytotoxic medicaments. The established quantitive indexes have significant predictive value. Activity index (AI) evaluates the presence of fresh inflammatory and potentially reversible lesions and chronicity index (CI) evaluate the presence of irreversible glomerular lesions such as sclerosis, tubular atrophy, interstitial fibrosis, etc. High AI and low CI, particularly in the class IV of LN, suggest the necessity of an aggressive treatment of the inflammatory process aiming to preserve the renal function. High CI and low AI characterize irreversible sclerosing lesions, where an aggressive treatment is considered unnecessary. Our experience suggests the necessity of introducing the new morphologic elements into the activity and chronicity scoring system which would correlate better the clinical symptoms. This should provide higher reliability of scoring, since it evaluates important elements in clinical-morphologic diagnosis of LN.

[Diagnostic dilemmas in surgical pathology]

In the majority of presented cases persisted certain diagnostic perplexities even after the careful investigations were performed, which required surgical exploration. For example, carcinomatous pericarditis as the sequel of metastasis from occult thyroid carcinoma and two cases of double malignity (papillary carcinoma and Hodgkin's lymphoma of the thyroid), retroperitoneal leiomyosarcoma and the clear cells renal carcinoma. All the cases were not successfully solved until the application of highly sophisticated and precise methods of immunohistochemical staining, which without a mistake confirmed our assumed histopathologic diagnosis. Metastatic lesion of folicular thyroid carcinoma in the adrenal gland should be mentioned because of the long remission period of 15 years following total thyroidectomy and neck irradiation during the primary therapy of thyroid carcinoma. It is very significant to point out that pathologic disorders such as undifferentiated neoplasm, strange inflammatory conditions, endocrine proliferative lesions deserve special attention because in certain cases consultative approach is necessary for obtaining the definite finding that can in some degree histoprognostically predict the outcome of pathologic process.

[Experimental study of the pathogenesis of frostbite. Part III. Significance of energy status of muscle tissue in the pathogenesis of frostbite]

The authors have investigated energy status of muscle tissue of the lower legs of Wistar rats subjected to freezing, as well as the dependence of ultrastructure changes in muscle tissue mitochondria on the intensity of freezing. The animals were divided into three experimental groups: two groups were exposed to cryoinjury of different intensity, while the third was the control one. Cryoinjury was applied over an experimental after thawing were taken samples of muscle tissue for the analysis of content of energy phosphates and carbohydrates' metabolites, respectively, as well as for morphometric analysis of mitochondria volume out of frozen right and unfrozen left lower legs. Results obtained from different experimental groups were compared mutually and with control group that was not exposed to cryoinjury, respectively. It was found that the freezing in muscle tissue caused hydrops degeneration of mitochondria, depletion of energy reserves, reduction of energy status and the activation of mechanism of anaerobic metabolism. All these alterations were proportional to the intensity of freezing and considerably influenced contractility function of muscle cells, causing prolonged spasm of arterioles in thawed tissue, i.e., rigor congelationis that was primarily defined as an important factor in the pathogenesis of ischemic impairment of thawed tissues.

[Experimental study of the pathogenesis of frostbite. Part II. Role of the sympathetic-adrenergic system in tissue reperfusion immediately after thawing]

The authors have investigated the role of sympathetic-adrenergic system in reperfusion of muscular tissue of the feet of Wistar rats immediately after thawing using alpha adrenergic blocker phentolamine methanesulfonate (Regitin). Cryoinjury was applied over an experimental model of local, controlled freezing of different intensity for certain experimental groups. Blood flow through microcirculation was measured by scintigraphy, following Tc-99m-pertechnetate clearance that was given in muscular mass of frozen right, as well as unfrozen left feet of rats. Results obtained in some experimental groups were compared mutually, as well as with the control group that was not exposed to cryoinjury. The investigations have revealed that immediately after thawing existed significant reduction, non-dependent of the intensity of freezing, in blood flow in microcirculation of both frozen and unfrozen feet of rats compared to the control group. Significant increase of microcirculatory blood flow in unfrozen feet was caused by blockade of sympathetic-adrenergic system, while the blood flow remained unchanged in the frozen ones. The reduction of blood flow in microcirculation of frozen tissues immediately after thawing was not associated with sympathetic-adrenergic factor.

[Experimental study of the pathogenesis of frostbite. Part I. Pathohistologic and ultrastructural changes in tissues immediately after thawing]

Histopathologic and ultrastructural changes in the tissues of frozen extremities of Wistar rats were investigated immediately after thawing. Three experimental groups were formed: two were exposed to cryoinjuries of different intensity, while the third was the control one. Cryoinjury was caused by experimental model of local, controlled freezing of hind, right extremities. Immediately after thawing the tissue samples were taken from frozen right and unfrozen left extremities, in which histopathologic and ultrastructural changes were compared mutually and with control group, respectively. It was observed that the freezing directly caused ultrastructural and histopathologic damage of the tissues that were manifested immediately after thawing and were proportional to the intensity of freezing. Simultaneously, in the tissues existed complex circulatory disorders manifested in open arteriovenous shunts, venous congestion and microcirculatory insufficiency caused by evident spasm of arteriolae that could be considered to be very significant pathogenetic factor in ischemic damage of unfreezed tissues.

[Personal experience with ex tempore diagnosis of neurosurgical biopsies using the smear method]

The results obtained by the use of the smear method were analyzed in ex tempore diagnostics of 240 neurosurgical biopsies, done in the period from 1991 to 1993. Thirty three different pathologic lesions were found that had their special morphology on smears, indicating the high specificity of this method. In 226 cases (94.17%) the diagnosis was established correctly, but in 14 cases (5.83%) it was not: in three cases the diagnosis was falsely negative and in 11 falsely positive. The main causes of the diagnostic errors were analysed and they included the subjective factors and uncommonness of the analyzed tissue samples. The accuracy of 94.17% enabled sufficiently reliable use of this method in ex tempore diagnostics of neurosurgical biopsies.

[Identification of bodies of soldiers carbonized in an armored transport vehicle]

The authors have presented the process and possibilities of identification of the carbonized bodies of the crew of the exploded military armoured transporter. In identification of the invaluable importance have been description, autopsy findings, questionnaires and their comparison as well as ways of identification of the carbonized bodies.

[Morphologic characteristics of persons killed in armored vehicles]

The authors have analysed macroscopic and microscopic changes in tissues and organs of 8 members of the Y.P.A. killed by granate explosion in the armoured vehicles. In all the analysed cases multiple mechanic injuries were found as well as combined mechanothermal injuries. Injuries caused by the blast wave were mainly found in the internal air-containing organs and three cases of solid blast injury were described too.