Platelet-rich plasma stimulates dermal microvascular endothelial cells and adipose derived stem cells after external radiation.

BACKGROUND: Platelet-rich plasma (PRP) products are currently suggested in the treatment of chronic wounds due to possible pro-angiogenic effects. Microvascular compromise represents the major component in radiogenic wound healing complications. The effects of PRP on irradiated cells of the cutaneous wound healing process are still poorly understood. MATERIAL AND METHODS: Human dermal microvascular endothelial cells (HDMEC) and human adipose derived stem cells (hASC) were cultured and irradiated with doses of 2 to 12 Gy. PRP was activated, characterized and added to the incubation media in different concentrations after external radiation. Cell count was determined 48 h after radiation using a semi-automated cell counting system. Levels of interleukin-6 (IL-6), basic fibroblast growth factor (bFGF) and soluble intercellular adhesion molecule-1 (sICAM-1) in the supernatants of HDMEC and hASC co-cultures were determined by enzyme-linked immunosorbent assay (ELISA). Non-irradiated hASC and HDMEC served as controls. RESULTS: The employed PRP preparations were characterized and contained platelet derived growth factor (PDGF-AB), vascular endothelial growth factor (VEGF), bFGF and high levels of sICAM-1. Addition of PRP to irradiated cultures of HDMEC and hASC prevented profound radiation-induced decline in cell numbers. 10% PRP restored cell numbers to levels of untreated, non-irradiated cultures. Basic FGF expression was decreased significantly in hASC monocultures treated with 10% PRP without external radiation and after irradiation with 6 and 12 Gy. These inhibitory effects of PRP were also observed in HDMEC. In contrast, co-cultures of HDMEC-ASC showed a dose-dependent increase in bFGF expression when treated with 5 or 10% PRP. Doses of 6 and 12 Gy increased IL-6 expression in cultures stimulated with 5% PRP. CONCLUSIONS: Use of PRP in co-cultures of hASC and HDMEC restores proliferative defects caused by external radiation probably by induction of bFGF. Under irradiated conditions, PRP might induce pro-inflammatory stimuli which could be beneficial in treatment of chronic wounds where healing processes are defective. Combined use of hASC and PRP products might be helpful in the treatment of radiogenic wounds.

MedJet--a new CO2-based disposable cleaning device allows safe and effective bowel cleansing during colonoscopy: a pilot study.

BACKGROUND AND STUDY AIMS: Complete bowel cleansing is mandatory for effective colon cancer screening and surveillance. The aim of the current pilot study, which was conducted in humans, was to test the safety and efficiency of a newly developed disposable cleaning device, the MedJet, for intraprocedural bowel cleansing. PATIENTS AND METHODS: Patients with screening or surveillance colonoscopy after previous polypectomy were included. The colonoscope was first inserted to the cecum and the overall cleansing was assessed according to the Ottawa scale. The MedJet device was used if colon cleansing had been incomplete. The MedJet catheter was passed over the working channel of the colonoscope and the colon was cleaned during withdrawal. The MedJet device delivered controlled jets comprising compressed CO2 and minimal amounts of sterile water, which allowed disintegration and removal of residual stool. The efficiency of cleaning was assessed according to the Boston scale. RESULTS: A total of 32 patients (16 female; mean age 61 years) were treated with the device. No device-related adverse or serious adverse events were noted. MedJet application during withdrawal provided effective and significant improvement in bowel cleansing (P = 0.005). Furthermore, 18 adenomas and 1 colon cancer, which were hidden behind stool remnants, could be identified in 11 patients following use of the MedJet device. However, the withdrawal times were prolonged (11.4±6.0 minutes) due to the additional cleaning procedure. All patients tolerated the procedure well. CONCLUSIONS: The new MedJet device enabled highly effective and safe bowel cleansing during colonoscopy. The catheter-based system was easy to use and CO2 was applied for cleansing. The procedure was well tolerated by patients.

Vaccinium myrtillus as an antidiabetic medicinal plant--research through the ages.

Bilberry leaves (Vaccinium myrtillus L.) were one of the most frequently used antidiabetic remedies of plant origin before the discovery of insulin. During the last century, many animal, clinical and phytochemical studies have been undertaken with this plant and its extracts and are summarized here. Overall, it must be concluded that the results were more or less disappointing and could not support the traditional use of bilberry leaves against diabetes mellitus which is sometimes recommended even up to the present day.

TGF-beta modulates programmed cell death in the retina of the developing chick embryo.

Programmed cell death (PCD) is a key phenomenon in the regulation of cell number in multicellular organisms. We have shown that reduction of endogenous transforming growth factor beta (TGF-beta) prevents apoptotic PCD of neurons in the developing peripheral and central nervous system, suggesting that TGF-beta is an important mediator of ontogenetic neuron death. Previous studies suggested that there are other pro-apoptotic molecules, nerve growth factor (NGF) and brain-derived neurotrophic factor, that induce cell death in the nervous system. In the developing chick retina, NGF induces PCD by activation of the p75 receptor. We have studied the role of TGF-beta and its putative interdependence with NGF-mediated PCD in the chick retina. We found that TGF-beta is present in the developing chick retina during the period of PCD and is essentially required to regulate PCD of retinal cells. TGF-beta 2, TGF-beta 3 and the ligand-binding TGF-beta receptor can be detected immunocytochemically in the central retina, a region where apoptosis is most prominent during the early period of PCD. Application of a TGF-beta-neutralizing antibody to chick embryos in ovo resulted in a decrease in the number of TUNEL-positive cells and a reduction of free nucleosome levels. In terms of magnitude, reduction of PCD caused by the neutralization of endogenous TGF-beta was equivalent to that seen after anti-NGF application. Neutralization of both factors did not result in a further decrease in apoptosis, indicating that NGF and TGF-beta may act on the same cell population. Furthermore, neutralization of TGF-beta did not affect the expression of NGF or the p75-receptor. Our results suggest that TGF-beta and NGF are both required to regulate cell death in the chick retina in vivo.

Wild-type p53 inhibits protein kinase CK2 activity.

The growth suppressor protein p53 and the protein kinase CK2 are both implicated in cellular growth regulation. We previously found that p53 binds to protein kinase CK2 via its regulatory beta-subunit. In the present study, we analyzed the consequences of the binding of p53 to CK2 for the enzymatic activity of CK2 in vitro and in vivo. We found that the carboxy-terminus of p53 which is a potent transforming agent stimulated CK2 activity whereas full length wild-type p53 which is a growth suppressor inhibited the activity of protein kinase CK2. Inhibition of protein kinase CK2 by p53 was dose-dependent and was seen for various CK2 substrates. Experiments with heat-denatured p53 and the conformational mutant p53(R175H) revealed that an intact conformation of p53 seemed to be necessary. Transfection of wild-type and of mutant p53 into p53-/- cells showed that the inhibition of p53 on CK2 activity was also detectable in intact cells and specific for wild-type p53 indicating that the growth suppressing function of p53 might at least be partially achieved by down-regulation of protein kinase CK2.

Reduction of endogenous transforming growth factors beta prevents ontogenetic neuron death.

We show that following immunoneutralization of endogenous transforming growth factors beta (TGF-beta) in the chick embryo, ontogenetic neuron death of ciliary, dorsal root and spinal motor neurons was largely prevented, and neuron losses following limb bud ablation were greatly reduced. Likewise, preventing TGF-beta signaling by treatment with a TbetaR-II fusion protein during the period of ontogenetic cell death in the ciliary ganglion rescued all neurons that normally die. TUNEL staining revealed decreased numbers of apoptotic cells following antibody treatment. Exogenous TGF-beta rescued the TGF-beta-deprived phenotype. We conclude that TGF-beta is critical in regulating ontogenetic neuron death as well as cell death following neuronal target deprivation.

Specific binding of protein kinase CK2 catalytic subunits to tubulin.

Protein kinase CK2 is composed of two regulatory beta-subunits and two catalytic alpha- or alpha'-subunits. To analyse these subunits individually we generated antibodies against unique peptides derived from the alpha-, alpha'- and beta-subunit. Immunofluorescence studies with these antibodies revealed the presence of all three CK2 subunits in the cytoplasm and weakly in the nucleus with strong signals around the nuclear membrane. Double staining experiments revealed a co-localisation of all three subunits with tubulin. A direct association between the CK2 alpha- and the alpha'-subunit and tubulin was confirmed by co-immunoprecipitation experiments as well as by Far Western analysis. There was no binding of the CK2 beta-subunit to tubulin. Thus, with tubulin we have identified a new binding partner specific for the catalytic subunits of CK2.

Regulation of p53 mediated transactivation by the beta-subunit of protein kinase CK2.

The growth suppressor protein p53 plays a main part in cellular growth control. Two of its key functions are sequence specific DNA binding and transactivation. Functions of p53 in growth control are regulated at least in part by its interaction with protein kinases. p53 binds to protein kinase CK2, formerly known as casein kinase 2, and it is phosphorylated by this enzyme. CK2 is composed of two regulating beta-subunits and two catalytic alpha- or alpha'-subunits and the interaction with p53 is mediated by the regulatory beta-subunit of CK2. Recently we showed that the beta-subunit could inhibit the sequence specific DNA binding activity of p53 in vitro. Based on this finding, we asked if a coexpression of the beta-subunit of CK2 with p53 in mammalian cells could inhibit the DNA binding activity of p53 in a physiological context. We found that the coexpression of the beta-subunit showed the same inhibitory effect as in the previous assays with purified proteins. Then, we investigated the effects of the coexpression of the beta-subunit of CK2 on the transactivation and transrepression activity of p53. We found that transactivation of the mdm2, p21(WAF1/CIP1) and cyclin G promoter was inhibited in three different cell lines whereas transactivation of the bax promoter was not affected in COS1 cells but down-regulated in MCO1 and SaosS138V21 cells. p53 mediated transrepression of the fos promoter was not influenced by coexpression of the CK2 beta-subunit. Taken together we propose a cell type dependent fine regulation of the p53 transactivation function by the CK2 beta-subunit in vivo, which does not affect p53 mediated transrepression.

Protein kinase CK2 interacts with a multi-protein binding domain of p53.

p53 is one of the most powerful negative regulators of growth. To manage this in an efficient way it has to interact with a set of different cellular proteins. Most contacts with the cellular environment occur in the N- or the C-terminal domain of the protein. Since we previously found that p53 binds to the regulatory beta-subunit of CK2 we now analyzed N- and C-terminal domains of p53 separately for the binding of protein kinase CK2, an enzyme which seems to have a certain importance for proliferation processes. With different overlay assays we could map the binding domain of protein kinase CK2 to a sequence between amino acids 325-344, a region which coincides with the interaction domain of some other p53 binding proteins. We also found that the regulatory beta-subunit of protein kinase CK2 binds independent of the catalytic alpha-subunit to this C-terminal domain of p53.

Regulation of the DNA binding of p53 by its interaction with protein kinase CK2.

Some of the numerous functions of the growth suppressor protein p53 are regulated by its interaction with viral and cellular proteins. C-terminal sequences of p53 are implicated in binding to the regulatory beta-subunit of protein kinase CK2. Using a p53-specific DNA binding element we found that the beta-subunit of CK2 inhibited the DNA binding of p53 whereas the alpha-subunit had no influence. The CK2 holoenzyme consisting of two alpha- and two beta-subunits led to a supershift in DNA binding of p53 similar to the p53-specific monoclonal antibody PAb421 as well as the C-terminus of p53. Thus, our results showed an individual role of the free beta-subunit of CK2 on the DNA binding activity of p53.

Quantification of conjunctival vascular reaction by digital imaging.

BACKGROUND: No objective evaluation of the conjunctival provocation test (CPT) was possible until now. OBJECTIVE: The aim of this study was to develop a tool that would enable us to monitor conjunctival allergic inflammation by objective measurements. METHODS: Twenty-four patients allergic to grass pollen were challenged by a CPT with grass pollen and genuine grass pollen in the "Vienna Challenge Chamber." Patients were randomized to treatment with placebo or topical application of an H1-receptor antagonist (azelastine). Vascular reaction of the conjunctiva was repeatedly monitored by special video equipment. The signal was sent to a digital frame grabber, and digital image analysis was done with the aid of the WCUE-3 program (Olympus Optical Co., Hamburg, Germany). RESULTS: The CPT led to an immediate increase of the red density. This extension was linear within the first 15 minutes. During the long-term challenge, the increasing vascular effect lasted 2 hours. During active treatment a consistent reaction pattern was obvious; however, the corresponding levels were statistically lower (p = 0.022). CONCLUSION: The calculation of red density of the conjunctiva by digital analysis proved to be a sensitive tool for measuring the conjunctival allergic reaction. It is possible to overcome the insufficient subjective evaluation of the CPT by objective measurements of the vascular reaction.

Postpolio survivors: needs for and access to social and health care services.

A needs assessment survey of 268 polio survivors residing in Maine explored the incidence of postpolio syndrome as well as perceived need for and access to social and health care services. A large proportion reported experiencing postpolio syndrome. Although knowledgeable of their condition, a majority perceived that they had no access to knowledgeable physicians or social and health care services and most were having difficulty coping. Findings indicate that polio survivors' self-appraisal of their illness status is related to their perceived need for and access to social and health care services. The need for community-based services, including medical, rehabilitative, educational, and social work services, is indicated.

Repeated mass treatment of schistosomiasis mansoni: experience in hyperendemic areas of Brazil. I. Parasitological effects and morbidity.

The current project, carried out in Viçosa (state of Alagoas, Brazil), sought to assess the impact of repeated mass treatment campaigns (4 times over a period of 5 years) upon the prevalence, egg counts and morbidity of schistosomiasis mansoni. Results were not impressive. Some control seems to have been achieved in zones of the town better-off in terms of sanitation and socio-economic conditions, while in other areas no effect whatsoever of chemotherapy was detected. Neither resistance to the drug (oxamniquine) nor its deterioration could be held responsible, since a short-term follow-up of a group of children personally treated by the authors showed rapid reinfection, after an excellent initial response. This study, complemented by data from an area in Pernambuco and a hospital survey over the period 1978-84, indicated that morbidity due to schistosomiasis was decreasing, although there was some evidence that other factors may be at least partly responsible for the increasing scarcity of "hepatosplenic" schistosomiasis. Schistosomiasis, a strictly focal problem, thus calls for a targeted approach to control. It is believed that chemotherapy alone will not suffice and that sanitation, vector control and, perhaps, health education are equally essential in areas which remain refractory to mass treatment.

Burnout among physical therapists.

Burnout results in a decrease in job performance because of excessive work-related stress. This study assessed the presence of burnout among physical therapists and determined if potential organizational and personal causes of burnout could predict symptoms of burnout. One hundred and sixty therapists surveyed nationwide met the established criteria for inclusion in the study; 84 (53%) stated that they were currently experiencing feelings of burnout. Subjects were asked to respond to the frequency of their symptoms of burnout and the relevancy of the list of potential causes. A standard multiple regression equation was completed on each of the five dependent variables (symptoms) predicted by the eight potential causes of burnout, four of which were organizational in nature and four of which were personal in nature. Four out of the five symptoms of burnout were significantly predicted by different potential causes. Burnout experienced by physical therapists can have a detrimental effect on patients, therapists, and the facilities in which they are employed.

Plasma alkaline phosphatase as a screening test for low zinc status in broiler hybrid chickens affected with 'clubbed down'.

Broiler chickens affected by 'clubbed down' on a number of Victorian farms had low liver zinc concentrations and low plasma alkaline phosphatase activities. The results indicated that the zinc status of affected flocks should be considered in future studies and that measurement of plasma alkaline phosphatase activity may be a useful means of screening large numbers of samples. Nutritional and genetic factors may be involved in the aetiology of 'clubbed down'.

Analysis of a community hospital employee tuberculosis screening program 31 months after its inception.

The employee tuberculosis screening program for this 450-bed, medical-surgical hospital was evaluated as of November 30, 1975. On that date, there were 1,488 employees, excluding physicians and medical and nursing students. Of the 626 employees tested at least twice with purified protein derivative, 28 converted their test from negative (zero induration) to positive (greater than or equal to 10 mm of induration), and 20 converted their tests from weakly reactive (3 to 9 mm of induration) to positive (greater than or equal to 10 mm of induration and showing a 6-mm or greater increase in induration over that resulting from the first test). The rate of conversion (tests with purified protein derivative going from negative to positive) was no different between the groups with high and with low degrees of exposure to tuberculous patients, suggesting the possibility of nonhospital-acquired infection in the latter group. A direct relationship existed between increasing age and increasing rate of conversion, suggesting that some of the convertors were not newly infected, but were persons with boosted reactivity. These data illustrate some of the practical problems of monitoring for tuberculous infections and subsequently offering preventive therapy to convertors.