Inducible nitric oxide synthase inhibition by mycophenolic acid

The focus of this review is the influence of an immunosuppressive xenobiotic drug mycophenolic acid on the induction of nitric oxide production in various cell types. The potential therapeutic significance of the cell-specific fine-tuning of nitric oxide release by mycophenolic acid, as well as the mechanisms behind the drug action are discussed.

Embodied Changes and the Search for Gynecological Cancer Diagnosis

The detection and successful treatment of cancers is dependent on timely presentation with abnormal and often subtle symptoms. In this article, we draw on research conducted with Australian immigrant women in 2001-02 who experienced delays in diagnosis of gynecological cancer. Data from in-depth interviews with women with gynecological cancer indicated a common trajectory of an "illness career" whereby the search for diagnosis was often painful and lengthy, either because women normalized the abnormal signs or because their experiences of bodily abnormality, pain, and dysfunction contrasted with medical explanations. This delay was sometimes exacerbated by structural barriers. As a result, diagnosis was often protracted, during which time women presented with symptoms that were dismissed or resulted in the misdiagnosis, with a resultant loss of confidence in clinical services.

Regulation of inducible nitric oxide synthase by cAMP-elevating phospho-diesterase inhibitors

Among the numerous genes controlled by cyclic adenosine monophosphate (cAMP)/protein kinase A signalling machinery is the gene encoding the inducible nitric oxide synthase (iNOS), an enzyme catalyzing the synthesis of a highly reactive free radical nitric oxide (NO). While being a major microbicidal and tumoricidal molecule, iNOS-derived NO has also been implicated in tissue destruction, as well as in regulation of inflammatory/immune cell function in various disorders associated with excessive inflammation. A feasible way for cAMP-dependent therapeutic control of inflammation, including iNOS-mediated NO synthesis, could involve the administration of drugs that block the enzymatic activity of cAMP-degrading phosphodiesterases (PDE). Indeed, cAMP-elevating PDE inhibitors can influence iNOS activation in different cell types in vitro, and their potent anti-inflammatory effects in experimental disease models and clinical studies were frequently accompanied with profound modulation of NO production. A set of conflicting data has been generated over the years, ranging from strong suppression to marked enhancement of NO release by cAMP-increasing PDE inhibitors, depending on cell-type, iNOS stimuli, and/or the agents used. The present review summarizes the data on iNOS modulation by cAMP-elevating PDE inhibitors and possible mechanisms behind it, speculating on its contribution to the therapeutic effects of these drugs.

Gynaecological day surgery and quality of care

The aim of the study was to explore the experiences of Australian public and private patients undergoing gynaecological day surgery in a public hospital. A telephone survey was conducted with 315 women within two days of hospital discharge. The findings indicate that patients generally favour the "in and out" experience of day surgery, with some reservations. Prior to hospital admission, private patients were less likely to have access to multiple sources of information as well as information that they found easy to understand. Alternative means of supporting women recovering from day surgery may be needed for those whose family members and/or friends cannot provide sufficient support following discharge. This study contributes to discussion on setting objective standards to evaluate the health system in the field of day surgery.

Remineralization effect of a low-concentration fluoride rinse in an intraoral model

A previous study showed that a sodium hexafluorosilicate-calcium chloride-based two-solution fluoride (F) rinse containing 6 mmol/l of F was more effective than a 12 mmol/l F sodium fluoride rinse in depositing F on tooth surfaces and increasing oral F levels. The present study compared the remineralization effects of these two rinses in an intraoral de- and remineralization model. The results showed that the 6 mmol/l F two-solution rinse produced greater remineralization in increasing lesion mineral contents and reducing lesion depths. The results demonstrated that the effectiveness of an F regimen depends less on the F dose and more on the ability of the treatment to utilize F efficiently for remineralization.

Declarative memory in early Parkinson's disease: serial position learning effects

This study tested the question of whether executive failure associated with frontal lobe deficit is associated with, and therefore, may influence declarative memory dysfunction in Parkinson's disease (PD). A variety of memory and 'frontal sensitive' tasks were used. The 'frontal lobe dysfunction' hypothesis was tested in part, by examining the serial position effects (SPE) of word list learning across five successive trials. The relationship between memory and 'frontal sensitive' task scores was tested also. A total of 39 PD patients early in the course of the disease and 31 matched controls were included in the study. The PD subjects showed mild memory deficits in comparison to the healthy control group. In the face of any hypothesized selective 'dysexecutive' syndrome in PD group, the latter groups learning strategy across five trials did not differ from that of the control group. Also, the expected interrelation between memory and 'frontal sensitive' scores was not obtained. Therefore, the hypothesis that frontal dysfunction alone may account for memory impairments in PD is not fully supported.

Interleukin-17 stimulates inducible nitric oxide synthase activation in rodent astrocytes

The effect of interleukin-17 (IL-17) on production of nitric oxide (NO) in rodent astrocytes was investigated. While IL-17 by itself did not induce NO production, it caused a dose-dependent enhancement of IFN-gamma-triggered NO synthesis in both mouse and rat primary astrocytes. In contrast, IL-17 was unable to stimulate NO synthesis in either murine or rat macrophages. IFN-gamma-triggered expression of mRNA for iNOS, but not for its transcription factor interferon regulatory factor-1 (IRF-1), was markedly elevated in IL-17-treated astrocytes. The induction of iNOS mRNA by IL-17 in IFN-gamma-pretreated astrocytes was abolished by antagonists of nuclear factor-kappaB (NF-kappaB) activation--a proteasome inhibitor MG132 and an antioxidant agent PDTC, as well as with specific p38 MAP kinase inhibitor SB203580. While IL-17 stimulated both IL-1beta and IL-6 production in astrocytes, only IL-1 was partly responsible for IL-17-induced NO release. Finally, IL-17 synergized with exogenous IL-1beta and TNF-alpha for astrocyte NO production. Having in mind a well-known neurotoxic action of NO, these results suggest a possible role for IL-17 in the inflammatory diseases of the CNS.

Amphotericin B potentiates the activation of inducible nitric oxide synthase and causes nitric oxide-dependent mitochondrial dysfunction in cytokine-treated rodent astrocytes

Because the neurotoxic effects of the antifungal drug amphotericin B (AMB) closely resemble those ascribed to the highly reactive gaseous free radical nitric oxide (NO), we investigated the effect of AMB on NO production in rodent astrocytes. AMB caused a dose-dependent increase of NO generation in interferon-gamma (IFN-gamma)-stimulated rat and mouse astrocytes, as well as in IFN-gamma + tumor necrosis factor-alpha (TNF-alpha)-activated rat astrocytoma cell line C6. Treatment of rat astrocytes with AMB markedly potentiated IFN-gamma-triggered expression of mRNA for iNOS, but not for its transcription factor IRF-1. The activation of transcription factor NF-kappaB was apparently required for AMB-induced iNOS mRNA expression, as the latter was abolished by NF-kappaB inhibitors: pyrrolidine dithiocarbamate and MG132. AMB-mediated enhancement of astrocyte NO production was partly dependent on endogenous IL-1, as shown by partial inhibition of AMB effect with IL-1 receptor antagonist. IFN-gamma + AMB treatment led to reduction of astrocyte mitochondrial respiration (measured by MTT assay) that has been completely reverted by selective iNOS inhibitor aminoguanidine. AMB toxicity toward IFN-gamma-stimulated astrocytes was dependent on both AMB and NO action, since AMB and NO-releasing substance SNP synergized in inducing astrocyte mitochondrial dysfunction. These results suggest that the enhancement of cytokine-induced iNOS activation in astrocytes and the subsequent release of high amounts of NO might be at least partly responsible for AMB neurotoxicity.

[Stress-rest myocardial tomoscintigraphy with 99mTc-tetrofosmin in the diagnosis of ischemic disease]

The aim of this study was to evaluate the accuracy of 1-day stress-rest technetium-99m tetrofosmin myocardial tomography in the identification of patients with coronary artery disease (CAD), and in the detection of the individual occluded coronary vessels. A total of 42 patients with suspected CAD were studied. Significant coronary narrowing (> or = 50% luminal stenosis) was detected by angiography in 22 patients. All patients received two i.v. injections of 99mTc tetrofosmin, one at peak exercises (370 MBq) and the other (740 MBq) at rest 3 h after exercise (images 15-30 min after injections for both studies). At visual analysis, all patients with CAD (> or = 50% luminal stenosis) (n-22) had an abnormal 99mTc tetrofosmin tomogram. Nine out of 20 patients without significant coronary narrowing (but with tortuosis, atheromathosis, with microvascular diseases) showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the identification of CAD was 100%, 55%, and 79%, respectively. Sensitivity, specificity and diagnostic accuracy in the identification of individuals with occluded coronary vessels were 100%, 76% and 85%, respectively. The results of this study demonstrate that 1-day exercise-rest 99mTc tetrofosmin single-photon emission tomographic imaging (SPET) is a suitable and accurate technique to identify patients with CAD and for detection of individual occluded coronary vessels.

[Risk factors for Clamydia infections of the genital organs in adolescent females]

INTRODUCTION

Chlamydia trachomatis (Ct) infections are the most common bacterial sexually transmitted diseases (STDs). The highest age-specific rates for chlamydia are found in adolescents. Female adolescents are more susceptible to STDs than older women because their cervical anatomic development is incomplete and especially sensitive to infection by certain sexually transmitted pathogens, and for some other features that characterize sexual behavior and health care behavior of the young people. The aim of this study was to identify risk factors and risk indicators statistically associated with the presence of Ct genital infection in adolescent females.

METHOD

The study group comprised 300 sexually active 19 years old girls who were attending the Mother and Child Health Care Institute of Serbia in the period from 1995 to 1997. The participants of this study were interviewed about their sexual behavior, health care behavior and their responsibility level in sexual relationships. Physical examination included microbiological and colposcopic findings. Vaginal and cervical microbiological examinations included the analysis of collected specimens for microscopic and culture analyses. Ct infection of the cervix was identified by direct immunofluorescence staining of smears using monoclonal antibodies. Colposcopic findings were divided in two groups: cervical ectopy and other findings. Data were statistically analyzed using step-wise linear regression.

RESULTS

The prevalence of Ct genital infection in the study group was 30.3%. Characteristics in adolescent girls with this infection were mostly as follows: first sexual intercourse was before the age of 17, first sexual partner was older, a great number of sexual partners, (more than 3-25.3% vs 20.1%; more than 4-16.5% vs 10.5%), sexual intercourse during casual contact (44.0% vs 34.4%) and high coital frequency (83.5% vs 72.7%). Among these characteristics, only the coital frequency was significantly associated with the probability of chlamydial genital infection (p < 0.05). Statistical findings about the use of contraceptives among the adolescents indicated that the level of safe sexual practice was low in the majority of girls, despite the presence of chlamydial genital infection. Nevertheless, the girls without Ct genital infection more frequently reported the condom as the method of contraception used for the longest adolescence period (41.6%) in comparison with the adolescent females infected by Ct (17.6%). This difference was statistically significantly associated with the possible manifestation of Ct genital infection (p < 0.05). Healthy adolescent females used condom more frequently at the last intercourse (37.3%) than girls with Ct genital infection (18.2%). Adolescent females often experienced only 0-2 methods of contraception (70.3% of girls infected with Ct and 59.8% of healthy girls). Health care behavior was poor in the examined girls. The suspicion of getting a STD was the reason for their first gynaecological examination in 25.3% of adolescent women with Ct genital infection and in 20.6% of healthy girls. Unwanted pregnancy during adolescence reported 16.5% of girls with Ct cervicitis and 15.8% of healthy girls. The existence of STD previous to examination was noted in 7.9% of infected girls and 7.7% of healthy subjects. Drug abuse reported 23.1% of studied adolescent females with Ct genital infection and 23.0% without it. A large proportion of both the adolescent females and their partners had negative attitudes toward the condom use (54.9% of infected girls and 57.1% of their partners; 32.1% of healthy girls and 35.9% of their partners). The difference between the attitudes toward the condom use among infected and healthy adolescent women and their partners was statistically significant (p < 0.001). Clinical findings of cervical ectopy were more frequent in girls infected with Ct (60.4%) in comparison to healthy girls (15.8%). These differences were also statistically significant (p < 0.001). Associated genital infections (vaginal and/or cervical) were more frequent in adolescent women with Ct cervicitis (56.0%) than in healthy girls (36.8%). The observed differences were statistically significant (p < 0.01).

CONCLUSION

Predictors of Ct genital infection in adolescent women, according to the step-wise linear regression analysis, were as follows: the presence of cervical ectopy, negative attitudes of adolescent girls and their partners toward the condom use; associated genital infections; frequent coitus; experience in causal sexual relations and older age of the first sexual partner. However, the possibility that this criterion provides imprecise identification of uninfected adolescent women and separation of only Ct infected women, is limited. Therefore, screening of the presence of Ct genital infections in all sexually active adolescent women is necessary.

Morphological and phase characterizations of retrieved calcium phosphate cement implants

A self-hardening calcium phosphate cement (CPC), consisting of equimolar amounts of tetracalcium phosphate and dicalcium phosphate anhydrous, hardens when mixed with water and forms a resorbable hydroxyapatite (HA) as the end-product. The objective of this study was to investigate the changes of the phase and morphology of the CPC during hardening and aging under in vivo conditions. CPC samples retrieved 12 h after hardening in vivo had already contained carbonated HA (type B), even though the initial cement mixture did not contain carbonate as one of the solid components. The mass fraction of carbonate in the 12-h sample was about 1%. The results suggested that under in vivo conditions carbonate is readily available and this allows formation of carbonated HA in favor of carbonate-free HA. The carbonate content of the CPC samples retrieved 3 months after implantation was similar to that of the 12-h samples, and the exterior surfaces of the 3-month samples appeared less crystalline than that of the 12-h samples.

Visuomotor skill learning on serial reaction time task in patients with early Parkinson's disease

This study tested the role of basal ganglia in visuomotor skill learning. Thirty-nine patients early in the course of Parkinson's disease (PD) and 30 patients after operation for an aneurysm of the anterior communicating artery (ACoA) were compared with 31 matched control subjects on a Serial Reaction Time test (SRTt). The patients with PD showed impaired visuomotor skill learning across the repeating blocks, in the presence of preserved declarative knowledge of embedded sequences, in contrast to the ACoA group in whom the reverse pattern was observed. The significant correlation in patients with PD between the standard neuropsychological and motor measures and the performance observed in the skill acquisition test, in the ACoA group and control subjects was not observed. The suggestion that this learning impairment could not be attributed to a motor deficit per se was also confirmed more directly for patients with PD. Accuracy of performance after the initial learning phase on the SRTt in patients with PD was associated predominantly with visual span capacity measures. Declarative knowledge of the embedded sequence of the SRTt was correlated to general cognitive and verbal span abilities in the PD group. The impairment observed in the PD group was not the result of a general decline in cognitive functioning, mood disturbances, or the severity of the motor symptoms.

Reappraisal of the quantity and nature of renal calcifications and mineral metabolism in the magnesium-deficient rat. Effects of treatment with potassium citrate or the combination magnesium citrate and potassium citrate

There is an urgent need for drugs capable of inhibiting renal calcifications, nephrocalcinosis and stones included, in humans. Current anticalcification medication is based mainly on alkalinization of the metabolism using potassium-containing citrate alone, despite the fact that calcium stone patients suffer marginally from both magnesium and potassium deficiency. We investigated the anticalcification efficacy of oral potassium citrate versus the combined administration of this drug and magnesium citrate in the magnesium-deficient rat developing corticomedullary nephrocalcinosis and luminal microliths in the long term. Among other things we employed specific stains for calcium and oxalate, light microscopy and element analysis for renal tissue and calcifications, respectively. In addition, minerals in renal tissue, urine and plasma were determined, as well as the state of extracellular calcium homeostasis. Magnesium deficiency caused pure calcium phosphate tissue deposits, containing no magnesium, but no deposition of calcium oxalate in the tubular lumen; tissue magnesium, calcium and phosphorus were increased, and there was marked potassium wastage via urine; despite mild hypercalcemia other signs of hyperparathyroidism were not found. Alkalinization with the two kinds of medication evoked an increase in urinary pH, citrate, and potassium; however, potassium citrate alone tended to aggravate renal concretions, whereas the combination of this drug with magnesium citrate completely prevented concretions. It was concluded that: (1) magnesium deficiency-induced calcifications are oxalate-free and are not sensitive to mobilization by alkalinization with potassium citrate, which might explain the failure of the drug to prevent stone recurrence in clinical stone patients, and (2) the combination of potassium citrate and magnesium citrate, which shows enormous anticalcification efficacy, deserves high priority in clinical trials aimed at evaluating strategies for the prevention of stones.

Koori Primary Health Care in Victoria: Developments in Service Planning

The Alma Ata 1978 Declaration on primary health care has conventionally been applied in developing countries, where medically trained personnel and other highly skilled health professionals and medical infrastructure are limited. Although such concepts have salience in relatively resource rich countries such as Australia, it is in Aboriginal and Torres Strait Islander health policy that they have become pivotal. A growing national focus on the development of Aboriginal primary health care capacity followed the release of the National Aboriginal Health Strategy (NAHS) in 1989 (Anderson, 1997). This focus consolidated further, following the evaluation of the National Aboriginal Health Strategy implementation in 1994 which preceded the transfer of administrative responsibility for the Commonwealth Aboriginal health program from the Aboriginal and Torres Strait Islander Commission (ATSIC) to the Commonwealth Health portfolio (DHFS, 1994). Within the strategic framework provided by federal state agreements, the development of primary health care services is a priority. In the current national policy framework domains of policy and strategy development have been identified as key developmental themes.

From theory to perioperative practice with Parse

The operating room nurse today is often thought of as a task skilled, highly technical, process oriented, and efficient member of the operating room team. Too often her/his nursing education and preparation in practice, theory and discipline are overlooked. Perioperative nursing as a specialty is an important, vital factor in the success of the planned surgical intervention. Perioperative nursing practice involves caring for the patient; it is patient-centered rather than task oriented. The RN combines both the physiologic and psychosocial aspects of nursing in delivery of care. This is reflective of the theoretical model used to plan effective nursing care. The RN interacting with the preoperative patient has a focus on being in true presence with the patient (Parse, 1987). The interrelationship sets in motion utilization of theory, reflecting nursing knowledge and practice.

Thermophysical properties of some pharmaceutical excipients compressed in tablets

PURPOSE

Thermophysical properties of three tableting excipients; microcrystalline cellulose, lactose and dicalcium phosphate dihydrate were observed to evaluate their ability to resist temperature induced changes in tablet form.

METHODS

Two thermophysical parameters, thermal diffusivity and specific heat, were measured by a pulse heating method. The materials were also evaluated by differential scanning calorimetry (DSC).

RESULTS

Microcrystalline cellulose in tablet form was found to be rather insensitive to heating and cooling treatments, even though the tablets seemed to remain in a stressed state four weeks after tableting. This stress, indicated by low temperature anomalies, was observed by the pulse method, but not by DSC. When magnesium stearate was incorporated as a lubricant within the microcrystalline cellulose powder, the thermophysical parameters indicated that the internal structure of the tablets changed with heating and cooling. Magnesium stearate eliminated the low temperature anomalies as well. The heat treatment changed the thermophysical properties of tablets made of the crystalline excipients lactose and dicalcium phosphate dihydrate, permanently causing irreversible structural changes.

CONCLUSIONS

The melting of the lubricant together with enhanced stress relaxation in the structure of microcrystalline cellulose most probably caused the improved thermal diffusivity. The observed thermophysical changes with the crystalline excipients were due to changes in tablet's structure and material. The combination of methods used was found to be an accurate and reliable way to obtain useful information on the structural changes and material relaxations of intact tablets during temperature treatment and age-related changes in material properties.

Liposome-entrapped superoxide dismutase reduces ischemia/reperfusion 'oxidative stress' in gerbil brain

Bilateral common carotid artery occlusion (15 min.) followed by two hours of recirculation reduced mitochondrial superoxide dismutase (SOD) and glutathione reductase (GR) activities, and increased susceptibility of mitochondrial membranes to in vitro lipid peroxidation in brain regions (i.e., cortex, striatum and hippocampus) of Mongolian gerbil. Intraperitoneal bolus injection (2 mg/kg b.w.) of liposome-entrapped CuZn superoxide dismutase (1-SOD) increased the endogenous SOD activity in normal brain tissue and, when given at the end of ischemia, counteracted both the ischemic reduction of endogenous SOD and the increased peroxidation of mitochondrial membranes. 1-SOD treatment was ineffective in reducing brain swelling, suggesting that superoxide radicals are not a main participant in the process of (post)ischemic brain edema formation.

'Therapeutic window's for multiple drug treatment of experimental cerebral ischemia in gerbils

The effects of the following drugs: nimodipine (1 mg/kg b.w., i.p.), 2-amino-5-phosphonovaleric acid (4 mg/kg b.w., i.p.) and propentofylline (25 mg/kg b.w., i.p.), administered (alone or in combination) at the end of 15 min bilateral ischemia in gerbils were evaluated on mitochondrial superoxide dismutase (SOD), glutathione reductase (GR), glucose-6 phosphate dehydrogenase (G6PD), monoamine oxidase (MAO) activities, and thiobarbituric acid reactive material (TBARM), and brain water content at 1 hour of reperfusion. The combined treatment virtually abolished early postischemic brain edema (4.1% v.s. 0.6%) and efficiently counteracted ischemia-induced changes [decreased SOD (79% v.s. 98%), GR (52% v.s. 105%) and MAO (25% v.s. 79%), and increased TBARM (198% v.s. 108%)]. The same combination of drugs administered 15 min before ischemia had a similar effect (e.g., reduced brain swelling and lipid peroxidation) as when given at the end of ischemia, whereas a limited or absent impact was seen when the drugs were given 15 min or 1 hour after ischemia, respectively. The data suggest that (post)ischemic brain swelling and mitochondrial dysfunction can be reduced by drugs which synchronously prevent processes induced in the early stages of reperfusion.

Microbial growth in clinically used enteral delivery systems

Potential contamination of enteral formulas has led to the development of policies limiting formula hangtimes. However, enteral administration bags can easily become contaminated during formula refilling. We prospectively studied enteral formula contamination when the hangtime of a prefilled 1000 ml pouch was compared with the standard 4-hour hangtime of a refilled enteral administration bag. Samples of formula collected from different locations along the enteral delivery system were cultured during 57 days of enteral hyperalimentation in 19 patients. The overall enteral formula contamination rate was 61%, where the greatest microbial growth occurred in reconstituted enteral formulas. The presence of microbial growth did not differ between canned formulas administered according to a 4-hour hangtime and the prefilled pouch. Greatest growth in all cases was at the distal tubing hub, where contamination during system manipulation or from the patient probably occurred. Use of prefilled enteral administration bags may delay formula contamination in the administration reservoir. A change in equipment design that would decrease the need to manipulate feeding sets or feeding tube connections should be further investigated.