Vasopressin in vascular regulation and water homeostasis in the brain.

It is well known that vasopressin participates in the regulation of the cardiovascular system, water electrolyte balance and many functions of the central nervous system. Receptors for vasopressin are widely distributed throughout the brain. They are present in neurons, in astrocytes and their perivascular processes, in endothelial and smooth muscle cells of blood vessels and in choroid plexus. Such a location suggests that vasopressin may participate in the regulation of vascular resistance in cerebral circulation and water homeostasis in the brain. Present review of the data published on this subject suggests that endogenous vasopressin is involved in brain pathology rather than in physiological regulations. Numerous studies have shown increased release of vasopressin and expression of vasopressin receptors in the brain following ischemia, trauma or subarachnoid hemorrhage in patients and in animal models of these diseases. Moreover, it has been demonstrated that antagonists of vasopressin V(1a) receptors are able to alleviate brain edema and spastic changes in blood vessels after subarachnoid hemorrhage. Vasopressin is also implicated in brain edema and in impairment of cerebral vasculature in hypo-osmotic states. The discussed results suggest that vasopressin V(1a) receptors antagonists may be a useful tool for the treatment of some states associated with cerebrovascular pathology.

[The influence of diptera on the domestic animals]. / Wplyw inwazji muchówek na zwierzéta gospodarskie.

The Diptera attacked domestic animals in Poland are: Simuliidae, Culicidae, Tabanidae, Gasterophilidae, Hypoder-matidae and Muscidae. The insect assail the crazing animals, mostly during sunny day dna at close of day. Lack of effective repelents and also difficulties with their usage, makes it impossible to complete extermination of parasitic insects in the environment. It is posible to effectively fight against Hypoderma bovis and Gasterophilus spp.

The effect of a vital bleaching technique on enamel surface morphology and the bonding of composite resin to enamel.

This study examined the effect of a nightguard vital bleaching procedure on enamel surface morphology and the shear bond strength of a composite resin luting cement to enamel. Extracted human teeth were bleached for 1 week using a vital bleaching product. Control teeth were brushed with a fluoride toothpaste and processed similarly to the bleached teeth, however the bleaching product was substituted with artificial saliva in the night guards. Teeth were stored in artificial saliva for 24 h, 1, 6 or 12 weeks and then examined for any surface changes using light and scanning electron microscopy. The effect of etching surfaces with 37% phosphoric acid was examined at the scanning electron microscope level. The shear bond strength of composite resin luting cement to both buccal and lingual surfaces of bleached and control teeth was determined. Light microscopy investigation suggested the bleaching process resulted in a loss of mineral from enamel which was evident 24 h after bleaching and was sustained following 12 weeks storage in artificial saliva. Scanning electron microscopy showed a definite change in the surface texture of the bleached enamel surface. Acid etching of the bleached enamel surface produced loss of prismatic form and the enamel appeared overetched. The mean shear bond strength between composite resin luting cement and etched enamel tended to be lower for bleached enamel surfaces, however no significant difference in shear bond strength was noted between control and experimental groups. The results of this study suggest that bleaching resulted in changes to the surface and subsurface layers of enamel. Although surface changes were observed in the etched enamel, the shear bond strength of composite resin luting cement to etched bleached enamel appeared to be clinically acceptable.

[Effect of Hydrochloric acid on invasion of Ascaris suum; enzyme activity in the digestive system and serum of newborn piglets]. / Wplyw roztworu kwasu solnego na inwazje ascaris suum oraz aktywnosc enzymów trawiennych przewodu pokarmowego i surowicy prosiat osesków.

The studies were carried out on twenty newborn piglets. They were divided into four groups. The groups no 3 and no 4 were given intragastric 0.18% HCl from the 3th day of experiment. The groups no 2 and no 4 were infected on the 7th day with 10,000 invasive eggs of Ascaris suum. The presence of A. suum larvae in the lungs and liver was examined after one week lasting invasion by Baermann method. The total acidity in the gastric content was measured. The activity of alpha-amylase, lipase and proteases was determined in the extracts from pancreas and in the contents of stomach, duodenum and jejunum. The level of pepsinogens and alpha-amylase in the animals serum was studied. The intensity of Ascaris invasion was slightly higher in the group which was given HCl than in the infected group without HCl. The activity of digestive enzymes in the both groups was similar. Only in the stomach content from the 4th group the activity of pepsin was higher (p < 0.05), and alpha-amylase and lipase were lower (p < 0.01) than in the 2nd and in the 3th group. The level of pepsinogens was always lower and alpha-amylase higher in the serum of infected animals than in uninfected groups.

Ultrastructure of cementogenesis as affected by growth hormone in the molar periodontium of the hypophysectomized rat.

To document the effect of hypophysectomy and growth hormone replacement on the ultrastructure of cementogenesis in the developing rat third molar, 12 female Wistar rats were randomly allocated to normal control, hypophysectomized or hypophysectomized plus human growth hormone (for 10 days) treatment groups. The results of this study by electron and light microscopy and morphometry have shown that qualitative and quantitative changes occur in the organelles of cementoblasts forming cellular cementum as a result of hypophysectomy and growth hormone replacement. After hypophysectomy, the changes of less prominent nucleoli and nuclear pores, less prominent Golgi apparatuses and decreased endoplasmic reticulum can be interpreted as diminished cementum matrix biosynthesis--an interpretation that can be confirmed morphometrically by less cellular cementum formation. Growth hormone replacement for 10 days reactivates protein synthesis and cementogenesis as evidenced by ultrastructural changes in cementoblasts and a greater production of cementum.

[The effect of Varroa jacobsoni invasion on bee colonies with queens of different breeds in the fourth year of the disease]. / Wplyw inwazji Varroa jacobsoni na rodziny pszczele z matkami róznych ras w czwartym roku trwania choroby.

The objective of the work was to determine the effect of invasion of Varroa jacobsoni on the bee colonies of different breeds in the fourth year of varrosis. It was found out that bee colonies which were not treated died in the fourth year of the disease, while treated ones were debilitated. The main loss concerned the bee colonies with augustonian and carnica queens. The most resistant were colonies with caucasian queens.

Developmental changes in the distribution of cecal lectin-binding sites of Balb-c mice.

The existence of lectin-binding sites was investigated in the cecum of Balb-c mice at seven developmental stages ranging from 18 days post conception (p.c.) to 8 weeks after birth. Nine horseradish-peroxidase-conjugated lectins (concanavalin A, Triticum vulgaris, Dolichus biflorus, Helix pomatia, Arachis hypogaea, Glycine maximus, Lotus tetragonolobus, Ulex europaeus, Limulus polyphemus) were applied to 5- to 7-microns thin paraffin sections of Bouin-fixed tissue. After DAB staining the sections were evaluated by light microscopy. It was shown that each lectin exhibits a unique developmental pattern. The adult binding patterns were established at the age of 3-4 weeks with only minor changes occurring thereafter. Considerable differences in binding patterns occurred not only between lectins of different groups but also between lectins with the same nominal monosaccharide specificity.

Dental abnormalities associated with a chromosome 2 deletion.

This case report describes the dental and physical anomalies observed in a young female patient who had a chromosome abnormality involving deletion of the q 33-q 35 region of chromosome 2. The dental dysplasia observed in this patient is proposed to be of genetic origin but the complication of anoxia at birth makes it difficult to assign the intellectual and physical impairments solely to the genetic deletion.

Soft tissue calcifications in the differential diagnosis of opacities superimposed over the mandible by dental panoramic radiography.

Not all opacities observed on panoramic dental radiographs are associated with the jaws. Two thousand six hundred and twenty-eight panoramic radiographs obtained from a single dental health clinic were evaluated for the presence of opacities associated with the mandible. Opacities were observed in 4 per cent of cases. The radiographic features of these opacities are presented. The importance of including soft tissue calcifications which may be superimposed over the mandible on panoramic views in the differential diagnosis is discussed. Information on the various soft tissue calcifications which can occur in this region is presented.

Hereditary opalescent dentine: variation in expression.

A family is described in which two females are more severely affected by hereditary opalescent dentine than the males. The genealogy of this family does not provide an accepted pattern of inheritance for this dentine anomaly. This may indicate that there is considerable variation in inheritance patterns for hereditary opalescent dentine and that this trait does not always exhibit 100 percent penetrance.

Micromorphologic features of dentin in vitamin D-resistant rickets: correlation with clinical grading of severity.

This study was a histological analysis of 20 primary teeth from 5 patients with 3 clinical grades of vitamin D-resistant rickets (VDRR). The results showed that the degree of globular dentin formation in the histological sections may be graded into Grades I-III in increasing order of severity. In Grade I, the amount of globular dentin was less than 50% of the total dentin thickness, and the interglobular spaces were small. By contrast, in Grade III severity, globular dentin extended throughout the entire thickness of dentin, and the interglobular spaces were large. In Grade II severity, the amount of globular dentin was more than half but did not involve the entire dentin thickness. These histologic grades of severity correlated directly with the clinical grades of the patients. In addition, the study found that lack of medical treatment in affected mothers might lead to globular dentin formation in the fetus in-utero. Conversely, adequate phosphate supplementation in a hypophosphatemic mother might prevent the formation of globular dentin in the fetus.

The behaviour of bioadhesive betamethasone tablets in the mouth.

Disk-shaped adhesive tablets, for treatment of mouth lesions, were prepared by direct compression of a mix of high viscosity sodium carboxymethyl-cellulose and 0.061% betamethasone valerate. They were evaluated in six healthy volunteers. The tablets hydrated rapidly, increased their wet weight fourfold in 15 min and maintained contact with the oral mucosa for at least 4 h. Erosion of the tablets was variable with only minor losses in one subject at all times tested, whereas over 80% tablet weight loss occurred in two subjects after 2.5 h. These differences were not solely related to differences in salivary flow. Loss of betamethasone occurred in parallel with the loss of weight from the tablet suggesting that drug release was mainly by erosion of the gelled polymer and not by diffusion from the matrix. The tablets provided prolonged contact with the mucosa but the intersubject variability and drug loss should be addressed to improve the formulation.

Traumatic bone cyst of the mandible; regression following aspiration.

A review of the literature suggests that traumatic bone cysts have been detected more frequently since the advent of panoramic radiography. Some authorities believe that these lesions may regress spontaneously without intervention within a period of time. Surgical exploration will enhance the bony repair of these cysts and is the usual recommended treatment. A case is reported in which complete regression of a traumatic bone cyst has occurred within 30 months of aspiration of its contents.