Oral mucosal grafts in laryngeal reconstruction (author''s transl)]

Thirty-one children with behavioural problems and learning difficulties were allergy tested for sensitivity to salicylates, artificial colours and flavours, eighteen children had a positive response, and 15 of these were given the Australian Version of the Feingold K.P. diet. Ninety-three per cent responded with improved behaviour in the areas of overactivity, distractability, impulsiveness and excitability. Sleep and enuresis problems were resolved partially or completely. This study demonstrates that the aforementioned elimination diet significantly affects behaviour.     

alpha-Ketoglutarate uptake in human fibroblasts

The effects of Corynebacterium parvum on host protection, tissue reaction and "in vivo" chemotaxis in Schistosoma mansoni infected mice were studied. The C. parvum was given intraperitoneally using a dose of 0.7 mg, twice a week (for 4 weeks), thirty days before (prophylactic treatment) or after infection (curative treatment). The host protection was evaluated through the recovery of adult worms by liver perfusion and was lower in the prophylactic group as compared to the control group (p = 0.018), resulting in 44% protection. The "in vivo" leukocyte response in both prophylactic and curative groups was higher as compared to the infected/non treated group (p = 0.009 and p = 0.003, respectively). Tissue reactions were described in the experimental and control groups, but there were not remarkable differences among them. The possible biological implications and relevance of the findings for the defensive response of the host and control of schistosomiasis are discussed.     

Perceived problems for self and others: self-protection by social downgrading throughout adulthood

In this study the authors investigated social downgrading as reflected in the difference between perceptions about the self and about "most people my age." A large cross-national probability sample of adults at different age levels throughout adulthood provided ratings of perceived problems expected for the self and for "most other people my age" with regard to 12 domains of life (e.g., health, marriage, and job). Results showed that with regard to all domains, younger, middle-aged, and older adults believed other people's problems to be more serious than their own problems in these domains. Social downgrading was particularly pronounced for those domains for which a given participant experienced problems himself or herself. This self-protection tendency under threat was particularly pronounced in the older adults. The function and adaptive values for social downgrading across adulthood and old age are discussed.     

The donor stage of orthotopic liver transplantation

First clinical experience of the harvesting (donor) stage of orthotopic transplantation of the liver in Russia is represented. During 5-year period in National Research Center of Surgery RAMS 16 orthotopic transplantations of the liver were carried out. Surgical modes of harvesting of the donor liver are detailed ("standard" and "fast"), the regimes and methods of preservation of the liver were determined. The influence of various parameters on function of the graft in postoperative period was established. Adequate selection of donors, correct and proper choice of donor-recipient pair, limited time of preservation allow to decrease the number of graft function failure and to eliminate primarily nonfunctioning grafts.     

Growth hormone and bone

It is well known that GH is important in the regulation of longitudinal bone growth. Its role in the regulation of bone metabolism in man has not been understood until recently. Several in vivo and in vitro studies have demonstrated that GH is important in the regulation of both bone formation and bone resorption. In Figure 9 a simplified model for the cellular effects of GH in the regulation of bone remodeling is presented (Fig. 9). GH increases bone formation in two ways: via a direct interaction with GHRs on osteoblasts and via an induction of endocrine and autocrine/paracrine IGF-I. It is difficult to say how much of the GH effect is mediated by IGFs and how much is IGF-independent. GH treatment also results in increased bone resorption. It is still unknown whether osteoclasts express functional GHRs, but recent in vitro studies indicate that GH regulates osteoclast formation in bone marrow cultures. Possible modulations of the GH/IGF axis by glucocorticoids and estrogens are also included in Fig. 9. GH deficiency results in a decreased bone mass in both man and experimental animals. Long-term treatment (> 18 months) of GHD patients with GH results in an increased bone mass. GH treatment also increases bone mass and the total mechanical strength of bones in rats with a normal GH secretion. Recent clinical studies demonstrate that GH treatment of patients with normal GH secretion increases biochemical markers for both bone formation and bone resorption. Because of the short duration of GH treatment in man with normal GH secretion, the effect on bone mass is still inconclusive. Interestingly, GH treatment to GHD adults initially results in increased bone resorption with an increased number of bone-remodeling units and more newly produced unmineralized bone, resulting in an apparent low or unchanged bone mass. However, GH treatment for more than 18 months gives increased bone formation and bone mineralization of newly produced bone and a concomitant increase in bone mass as determined with DEXA. Thus, the action of GH on bone metabolism in GHD adults is 2-fold: it stimulates both bone resorption and bone formation. We therefore propose "the biphasic model" of GH action in bone remodeling (Fig. 10). According to this model, GH initially increases bone resorption with a concomitant bone loss that is followed by a phase of increased bone formation. After the moment when bone formation is stimulated more than bone resorption (transition point), bone mass is increased. However, a net gain of bone mass caused by GH may take some time as the initial decrease in bone mass must first be replaced (Fig. 10). When all clinical studies of GH treatment of GHD adults are taken into account, it appears that the "transition point" occurs after approximately 6 months and that a net increase of bone mass will be seen after 12-18 months of GH treatment. It should be emphasized that the biphasic model of GH action in bone remodeling is based on findings in GHD adults. It remains to be clarified whether or not it is valid for subjects with normal GH secretion. A treatment intended to increase the effects of GH/IGF-I axis on bone metabolism might include: 1) GH, 2) IGF, 3) other hormones/factors increasing the local IGF-I production in bone, and 4) GH-releasing factors. Other hormones/growth factors increasing local IGF may be important but are not discussed in this article. IGF-I has been shown to increase bone mass in animal models and biochemical markers in humans. However, no effect on bone mass has yet been presented in humans. Because the financial cost for GH treatment is high it has been suggested that GH-releasing factors might be used to stimulate the GH/IGF-I axis. The advantage of GH-releasing factors over GH is that some of them can be administered orally and that they may induce a more physiological GH secretion. (ABSTRACT TRUNCATED)     

Effect of nitrite on primary photosynthetic processes in isolated chloroplasts of wheat grown under various conditions of nitrogen supply

In wheat chloroplasts, NO2- (5 mM) inhibited non-cyclic phosphorylation coupled to the linear electron flow through both photosystems but stimulated cyclic phosphorylation with phenazine methosulfate (plus diuron) and electron flux from an artificial electron donor through PSI and methylviologen to oxygen. During light energization of chloroplasts, NO2- increased the F740/F695 ratio in the low-temperature fluorescence spectra, thus suggesting that the energy of absorbed quanta is redistributed in favor of PSI. Nitrite also stimulated the activity of Mg2+-dependent H+-ATPase. Changes in the slow component of the induction curve of delayed fluorescence also suggest that NO2- affects energy transformation processes that are coupled to electron transport in the chloroplasts. Nitrite had no effect on these functional characteristics of thylakoids and chloroplasts isolated from plants grown under nitrogen deficiency in the medium.