Cell-phone based assistance for waterworks/sewage plant maintenance.

Cell-phones are now incorporating the functions necessary for them to be used as mobile IT devices. In this paper, we present our results of the evaluation of cell-phones as the mobile IT device to assist workers in industrial plants. We use waterworks and sewage plants as examples. By employing techniques to squeeze the SCADA screen on CRT into a small cell-phone LCD, we have made it easier for a plant's field workers to access the information needed for effective maintenance, regardless of location. An idea to link SCADA information and the plant facility information on the cell-phone is also presented. Should an accident or emergency situation arise, these cell-phone-based IT systems can efficiently deliver the latest plant information, thus the worker out in the field can respond to and resolve the emergency.

Onset and evolution of nephropathy in rats with spontaneous diabetes mellitus.

The occurrence of renal diabetic complications was studied in diabetic nonobese IIM/FmeSS (eSS) rats. The results were compared with eumetabolic Wistar rats paired by sex and age. Between 6 and 12 months of age, eSS male rats had higher fructosamine values and glucose intolerance as well as increasing proteinuria and uremia. Enhancement in water, calcium and phosphorus fractional excretion with a concomitant lower sodium excretion, was observed from 12 months of age on. 18- and 21-month-old eSS rats exhibited fasting hyperglycaemia and rising values of fructosamine, glucose intolerance and glycosuria. Simultaneously, a notorious worsening of proteinuria as well as alterations in glomerular filtration were verified. Optic microscopy of 12-month-old eSS rat kidneys showed areas of tubular dilatation with protein cylinders. In 21-month-old eSS animals, kidneys appeared overtly damaged. Increased capsular, glomerular and Henle's thin loop diameters were verified in 12- and 21-month-old eSS rats. Glomeruli showed diffuse hypertrophy of mesangial tissue and thickening of the basement membrane. Areas of markedly atrophic and dilated tubules containing acidophilic proteinaceous material were observed. At age of 21 months, kidneys of eumetabolic Wistar control rats presented foci of interstitial and pielic inflammatory infiltrates.

Induction and suppression of endothelial cell apoptosis by sphingolipids: a possible in vitro model for cell-cell interactions between platelets and endothelial cells.

Because sphingosine (Sph) is actively incorporated into platelets and rapidly converted to sphingosine 1-phosphate (Sph-1-P), which is then released extracellularly, it is important to study the effects of Sph and Sph-1-P on endothelial cells from the viewpoint of platelet-endothelial cell interaction. In this study, we found that Sph, as well as ceramide, induces apoptosis in human umbilical vein endothelial cells (HUVECs). In contrast, Sph-1-P acts as a HUVEC survival factor; this bioactive lipid was shown to protect HUVECs from apoptosis induced by the withdrawal of growth factors and to stimulate HUVEC DNA synthesis. In metabolic studies, [3H]Sph, incorporated into HUVECs, was converted to [3H]Cer and further to [3H]sphingomyelin in a time-dependent manner, whereas [3H]Sph-1-P formation from [3H]Sph was weak and transient. These findings in HUVECs are very different from those of platelets, which possess a highly active Sph kinase but lack Sph-1-P lyase. As a result, platelets abundantly store Sph-1-P, whereas HUVECs contain much less Sph-1-P. Finally, HUVECs, in contrast to platelets, failed to release Sph-1-P extracellularly, indicating that HUVECs themselves are not able to supply the survival factor Sph-1-P, but receive it from activated platelets. Our results suggest that platelets may maintain the integrity of endothelial cells by incorporating Sph and releasing Sph-1-P.

[Intestinal alterations and reduction of growth in prepuberal rats fed with soybean]. / Alteraciones intestinales y disminución del crecimiento en ratas prepúberes alimentadas con soja.

Weanling rats from the inbred lines alpha and beta were fed with a soybean-cereal mixture used for human consumption (AN). A group fed with laboratory rat chow was used as reference (AC). Growth and other nutritional parameters as well as intestinal morphohystometry were evaluated from 22 to 44 days of age. Growth rate and final weight were greater with AC in both lines of rats. The greater initial food conversion efficiency of AN diet, compared to AC, decreased rapidly with the progression of age, particularly in the beta strain. Nitrogen (N) and lipid fecal contents were significantly larger for AN in both lines. Apparent nitrogen digestibility, expressed as the difference between N intake and fecal N with respect to N intake was AC < AN (p < 0.01) for line alpha and AC > AN (p < 0.01) for line beta. The weight and the mucosal total width of the small intestine were AC > AN in both lines. AN produced a significant decrease of villi goblet cells in both strains (p < 0.005). Cecum weight was AC > AN (p < 0.01) for the beta strain. These results alert about uncontrolled consumption of soybean products without adequate inhibition of antinutritional factors, a potential risk for growing animal populations.

Quantification of sphingosine derivatives in human platelets: inducible formation of free sphingosine.

To elucidate the physiologic role of sphingolipid-derived products as signaling molecules, we analyzed the levels of endogenous sphingosine (Sph) derivatives in human platelets. When the platelets were stimulated with thrombin or 12-O-tetradecanoylphorbol 13-acetate, neither ceramide formation nor sphingomyelin hydrolysis was observed, which suggests that the sphingomyelin cycle may not be an essential part of the signaling pathway under these conditions. In contrast, Sph was found to increase in platelets upon stimulation. The level of Sph 1-phosphate, which is formed from Sph by the action of Sph kinase, was not affected under our conditions. Although it has been established that Sph inhibits protein kinase C, which regulates the functional responses of the platelets, Sph levels which exert an inhibitory effect on protein kinase C cannot be attained under physiological conditions (without exogenous Sph). Considering the stimulation of the synthesis of Sph by the physiological agonist thrombin, we speculate that Sph is a signaling molecule of physiological importance in platelets, but protein kinase C may not be its target.

Entrapment of islets into reversible disulfide hydrogels.

Currently, there are three types of devices for a bioartificial pancreas; microencapsulation, an extravascular diffusion chamber, and an intravascular diffusion chamber. The purpose of the present study was to provide a new extracellular matrix hydrogel for the devices of extra- and intravascular diffusion chamber types. As the sol-gel transition of this hydrogel is reversible, refilling of islets in vivo will be possible without a severe traumatic procedure. The hydrogel was produced from a polyacrylamide derivative carrying thiol groups synthesized by radical copolymerization of acrylamide and N,N'-bis-acrylcystamine, followed by reduction of the disulfide bonds in the copolymer. This water-soluble copolymer was used to entrap hamster islets by re-formation of disulfide bonds on the copolymer to produce a hydrogel. The formed hydrogel was easily reliquefied by reduction of the disulfide crosslinks to thiols. Insulin release from the islet-entrapped hydrogel continued for more than 1 month when examined in vitro. A static glucose stimulation test for the entrapped islets exhibited an increased insulin release.

Sphingosine 1-phosphate, a bioactive sphingolipid abundantly stored in platelets, is a normal constituent of human plasma and serum.

Although sphingosine 1-phosphate (Sph-1-P) is reportedly involved in diverse cellular processes and the physiological roles of this bioactive sphingolipid have been strongly suggested, few studies have revealed the presence of Sph-1-P in human samples, including body fluids and cells, under physiological conditions. In this study, we identified Sph-1-P as a normal constituent of human plasma and serum. The Sph-1-P levels in plasma and serum were 191+/-79 and 484+/-82 pmol/ml (mean+/-SD, n=8), respectively. Furthermore, when Sph-1-P was measured in paired plasma and serum samples obtained from 6 healthy adults, the serum Sph-1-P/plasma Sph-1-P ratio was found to be 2.65+/-1.26 (mean+/-SD). It is most likely that the source of discharged Sph-1-P during blood clotting is platelets, because platelets abundantly store Sph-1-P compared with other blood cells, and release part of their stored Sph-1-P extracellularly upon stimulation. We also studied Sph-1-P-related metabolism in plasma. [3H]Sph was stable and not metabolized at all in plasma, but was rapidly incorporated into platelets and metabolized mainly to Sph-1-P in platelet-rich plasma. [3H]Sph-1-P was found to be unchanged in plasma, revealing that plasma does not contain the enzymes needed for Sph-1-P degradation. In summary, platelets can convert Sph into Sph-1-P, and are storage sites for the latter in the blood. In view of the diverse biological effects of Sph-1-P, the release of Sph-1-P from activated platelets may be involved in a variety of physiological and pathophysiological processes, including thrombosis, hemostasis, atherosclerosis and wound healing.

Activation of protein-tyrosine kinase Syk in human platelets stimulated with lysophosphatidic acid or sphingosine 1-phosphate.

It has been reported that not only lysophosphatidic acid (LPA) but also its sphingolipid counterpart, sphingosine 1-phosphate (Sph-1-P), induce platelet functional responses. We report here Syk activation in human platelets stimulated with these lysophospholipids. LPA rapidly induced platelet protein-tyrosine phosphorylation, including that of Syk, and Syk activation, assessed by immunoprecipitation kinase assay. Sph-1-P, although rather weaker, mimicked LPA in inducing these tyrosine kinase-related events. Pretreatment of platelets with staurosporine, a potent protein kinase inhibitor, diminished LPA-induced Syk phosphorylation and activation, but not intracellular Ca2+ mobilization. These results demonstrate that, in platelets, the bioactive lysophospholipids induce Syk activation, which, however, may not be related to Ca2+ mobilization.

Female reproductive profile in a fertile, genetically obese line of rats.

The female reproductive profile of a fertile genetically obese line of rats, named beta, is characterized. Hypophysis, ovaries, oviducts, and uteri weights do not differ from those of nonobese controls. Histological features in ovary, uterus, and vagina in beta line and alpha controls are similar, in agreement with classical descriptions in the subject. Vaginal opening, number of estrus, number of corpora lutea at ovulation time, and pregnancy patterns (i.e., ovary weight, number of corpora lutea, sites of implantation, and living fetuses, as well as productivity, fertility, litter size, and preweaning mortality) show no significant differences between obese and nonobese animals. From a reproductive standpoint, obese beta line would behave as nonobese. Up to now beta would represent the only fertile genetically obese line of rats, appearing as a profitable biological model to widen and deepen reproductive analysis on obesity.

Effects on hamster vaginal development of a single dose of testosterone or estradiol given neonatally.

Postnatal injections of a single dose of testosterone propionate or estradiol benzoate to newborn female hamsters produce a precocious vaginal opening at 5 days of age. Vaginal postnatal development, histologically, has shown that in testosterone-propionate-injected animals sinusal vagina is absent. The Müllerian vagina presented a stimulated epithelium at early ages. After 40 days, the Müllerian epithelium was stratified keratinized, with zones of stratified cuboidal epithelium. In estradiol-benzoate-treated animals, the Müllerian epithelium rapidly changes to stratified keratinized epithelium (10 days), with zones of stratified cuboidal after 20 days of life. The sinusal epithelium was stratified squamous at 10 days, and after 40 days changes to stratified keratinized epithelium were seen. Probably, early changes are due to a direct effect of steroid action. Later effects are due to ovarian secretion. Histologically, no significant changes were observed in the preputial and urethral glands. The clitoris showed malformations.

Postnatal development of vagina, clitoris and urethral glands of the golden hamster.

We have made a histological study of the postnatal development of the clitoris, preputial glands, urethral glands and vagina of the golden hamster. The 'phallic groove' of the clitoris is closed at 10 days of life, then the urethra has a cuboidal stratified, a stratified squamous and a stratified keratinized epithelium. The preputial glands are composed of branched saccular glands. These glands develop, with few changes during their maturation period. Formation of the urethral glands begins at 5 days and the alveoli are fully developed at puberty. The hamster vagina has two origins; the upper part is Müllerian, the caudal part is sinusal. The wall of the Müllerian vagina has a cylindrical epithelium at birth, which becomes 'double epithelium' at puberty and thereafter changes cyclically in connection with the estrous cycle. The sinusal vagina is solid at birth, its lumen being formed in the first 10 days of life and its wall having a cuboidal stratified epithelium. At 15 days it becomes a stratified keratinized epithelium, which will later line the vaginal pouch. At the 5th day, an ectodermic invagination (stratified keratinized epithelium) is observed in the zone of the future introitus. At the time of vaginal opening this zone forms the distal segment.