Dental student readiness to treat special care patients upon graduation

INTRODUCTION

There has been a global increase in patients with special needs. Undergraduate dental curricula need to adjust to meet the needs of these patients. This study aimed to identify how confident final year dental students felt about treating patients with special needs upon graduation and evaluate the influence that the curriculum had on their preparedness based on competencies outlined by the International Association for Disability and Oral Health (iADH).

METHODS

A questionnaire was administered to final year dental students at two different Universities in Scotland and in Spain to: (1) evaluate how prepared students felt when treating patients with special needs and (2) assess the competencies outlined by iADH.

RESULTS

The response rate was 18.4% (30/163 students). Overall, 83.3% of the students (n = 25) perceived they would benefit from more practical sessions with patients with learning and physical disabilities to improve their clinical management of these patients. 53.3% (n = 16) didn't feel that had the knowledge to properly treat all special care dentistry (SCD) patients upon graduation (scored 5 or 6 on the IADH competency framework). 83.3% of the students (n = 25) felt that the mode of teaching should be problem-based complemented with small group seminars.

CONCLUSION

Students from both Universities agreed that more clinical practice might be required for them to further their skills to treat special needs patients upon graduation, which correlates with the need to have more practical sessions to consolidate competency 4 (communication skills with SCD) and competency 6 (clinical management of patients requiring SCD).

Inhibition of PKC-dependent extracellular Ca2+ entry contributes to the depression of contractile activity in long-term pressure-overloaded endothelium-denuded rat aortas

We examined the contractile responsiveness of rat thoracic aortas under pressure overload after long-term suprarenal abdominal aortic coarctation (lt-Srac). Endothelium-dependent angiotensin II (ANG II) type 2 receptor (AT₂R)-mediated depression of contractions to ANG II has been reported in short-term (1 week) pressure-overloaded rat aortas. Contractility was evaluated in the aortic rings of rats subjected to lt-Srac or sham surgery (Sham) for 8 weeks. ANG I and II levels and AT₂R protein expression in the aortas of lt-Srac and Sham rats were also evaluated. lt-Srac attenuated the contractions of ANG II and phenylephrine in the aortas in an endothelium-independent manner. However, lt-Srac did not influence the transient contractions induced in endothelium-denuded aortic rings by ANG II, phenylephrine, or caffeine in Ca²⁺-free medium or the subsequent tonic constrictions induced by the addition of Ca²⁺ in the absence of agonists. Thus, the contractions induced by Ca²⁺ release from intracellular stores and Ca²⁺ influx through stored-operated channels were not inhibited in the aortas of lt-Srac rats. Potassium-elicited contractions in endothelium-denuded aortic rings of lt-Srac rats remained unaltered compared with control tissues. Consequently, the contractile depression observed in aortic tissues of lt-Srac rats cannot be explained by direct inhibition of voltage-operated Ca²⁺ channels. Interestingly, 12-O-tetradecanoylphorbol-13-acetate-induced contractions in endothelium-denuded aortic rings of lt-Srac rats were depressed in the presence but not in the absence of extracellular Ca²⁺. Neither levels of angiotensins nor of AT₂R were modified in the aortas after lt-Srac. The results suggest that, in rat thoracic aortas, lt-Srac selectively inhibited protein kinase C-mediated activation of contraction that is dependent on extracellular Ca²⁺ entry.

[Evaluation of a pharmaceutical care program to improve adherence to antiretroviral therapy]

OBJECTIVE

To establish the impact of a pharmaceutical care program on the improvement of adherence to antiretroviral therapy, and on patient immunologic and virologic outcome.

MATERIALS AND METHODS

A multicenter, observational, prospective study in a HIV-infected patient cohort under treatment with antiretrovirals selected by random sampling in 19 Spanish hospitals. The study lasted 12 months, in which the program was applied through a baseline preprocedural visit and 4 quarterly visits. Adherence estimation was based on pill counting. An adherence > or = 90, or > or = 95% was considered adequate (in two time points).

RESULTS

541 patients were included, most of them were males (68.8%) between 20 and 78 years of age. Major risk groups included injecting drug users (43.4%) and heterosexuals (29.4%). Sixty percent had already received treatment for more than 3 years. Mean baseline viral load and CD4 count values were 32,866 copies/ml and 485 cells/mm3, respectively. Throughout the study a slight increase in the percentage of adherent patients was seen; however, statistical significance was not reached (64.3 and 79.2% of patients showed an adherence > 95 and > 90%, respectively, during the fourth quarter, versus 59.8 and 75.5% at baseline). A statistically significant decrease in viral load and increase in CD4 cells was seen following program application. The percentage of patients with a viral load < 200 copies/ml was 72.2, 76.7, and 75.0% at the 2nd, 3rd, and 4th quarters, respectively, versus 64.2% at baseline. CD4 cell counts increased by 50 cells/mm3 on average from the start to the end of follow-up.

CONCLUSIONS

Patients included in the program had a good immunologic and virologic outcome, and a trend towards an increased percentage of patients with good adherence was also seen. These results confirm the need to implement follow-up programs for patients receiving antiretrovirals in order to ensure maximum therapeutic benefits.

Influence of oxidation and crosslinking on oxygen binding properties of mouse erythrocytes

Different chemical treatments for mouse erythrocyte modification has been used. Oxidation treatments with Ascorbate/Fe(3+), a system able to react with intracellular proteins, produced a displacement of the O(2) binding equilibrium curve to a higher affinity behaviour with loss of the haemoglobin cooperativity for oxygen binding. Incubation of mouse erythrocytes with diamide showed that at low reagent concentration (0.8 mM) no modification on oxygen binding equilibrium curves was observed. At higher reagent concentration (2.0 mM), an increased affinity and a disappearance of the cooperative behaviour can be observed. Additionally, crosslinking reactions on mouse erythrocytes with band 3 crosslinkers seemed to affect oxygen binding properties when used at a crosslinker concentration of 5 mM. Oxyhaemoglobin levels in crosslinked and diamide-treated erythrocytes are similar to those found in control cells. In contrast, ascorbate/Fe(3+) treatments produced an increment in the proportion of methaemoglobin, decreasing the oxyhaemoglobin levels in these oxidized erythrocytes.

alpha 1D-adrenoceptors contribute to the neurogenic vasopressor response in pithed rats

The aim of the present study was to assess the role of vascular alpha 1D-adrenoceptors in the sympathetic vasopressor response in vivo. Specifically, we evaluated the effect of a selective alpha 1D-adrenoceptor antagonist, BMY 7378 (8-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-8-azaspiro(4,5)dec ane-7,9- dione 2HCl), on the vasopressor response induced by preganglionic (T7-T9) sympathetic stimulation in the pithed rat. The vasopressor response was dose-dependently sensitive to inhibition by intravenous BMY 7378 (0.1, 0.31, 1 and 3.1 mg/kg), doses of 1 and 3.1 mg/kg being equally effective. Like BMY 7378, 5-methylurapidil (0.1, 0.31, 1 and 3.1 mg/kg) antagonized the vasopressor response to spinal stimulation; doses of 1 and 3.1 mg/kg were also equally effective. In combination experiments, BMY 7378 (1 mg/kg, i.v.) and the alpha 1A-adrenoceptor antagonist, 5-methylurapidil (1 mg/kg, i.v.), showed an additive effect. The present results demonstrate that the alpha 1D-adrenoceptor subtype plays an important role in the pressor response to sympathetic nerve stimulation in the pithed rat, and confirm the participation of the alpha 1A-adrenoceptor subtype in the same response.

Hematopoietic cell transplantation using plasma and DMSO without HES, with non-programmed freezing by immersion in a methanol bath: results in 213 cases

A simplified cryopreservation method for bone marrow (BM) and peripheral blood progenitor cells (PBPC) was utilized in hematopoietic cell transplantation of 213 patients with hematological or solid neoplasms after ablative chemotherapy (187 with peripheral blood progenitor cells and 26 with bone marrow). Cells were cryopreserved, after addition of autologous fresh plasma with DMSO, without HES, by freezing to -80 degrees C in a methanol bath and non-programmed freezer. For the patients autotransplanted with PBPC, the median period necessary for recovery of more than 0.5 x 10(9)/l granulocytes was 11 days (range 6-44), and 15 (8-204) days were required to obtain more than 20 x 10(9)/l platelets. For the patients autotransplanted with BM, the median period necessary to recover >0.5 x 10(9)/l granulocytes was 12 days (range 9-33), and 24 (12-57) days to obtain more than 20 x 10(9)/l platelets. These results support this method as being very effective in achieving high-quality cryopreservation. The procedure, which uses a non-programmed freezer, simplifies and reduces enormously the cost of the technical measures currently in use, enabling its adoption in almost any clinical oncological institution.

Visceral leishmaniasis in haemophiliac patients with HIV: four case reports

Visceral leishmaniasis (VL), an endemic parasitosis in Spain, is increasing as an important opportunistic infection in AIDS patients. We describe four cases of severe haemophilic patients with end-stage HIV disease who present with visceral leishmaniasis. We report the clinical course, methods of diagnosis and response to therapy. From the assessed clinical data it does not appear to be any difference with regard to VL either in other HIV risk groups or in immunocompetent groups. In contrast with previous reports, we have found that despite their immunodepressed state, positive serology for Leishmania was found in three of the four cases. A similar observation has been made in patients with VL who are immunodepressed because of other reasons. We also confirm previous reports of poor response and intolerance of antimony treatment, the deteriorating course of the disease in AIDS patients and that there is only a slight relationship between the disease and the cause of patient death. We agree with the proposition that this pathology ought to be included in the definition critera for AIDS.

Pharmacokinetic properties and in-vivo biological activity of recombinant human erythropoietin encapsulated in red blood cells

The in-vivo survival of 51Cr-labelled murine red blood cells (RBCs) loaded with recombinant human erythropoietin (rhEpo-RBCs) was slightly lower than that of normal RBCs. Intravenous administration to normal mice of the encapsulated rhEpo shows the pharmacokinetic bicompartmental profile typical of the free rhEpo. Distribution and elimination half-life values for the RBC-entrapped rhEpo were no longer than those for the free protein. The area under the curve value was significantly increased for rhEpo-RBCs. Hypertransfused polycythaemic mice were evaluated as an adequate animal model to study the in vivo biological activity of encapsulated rhEpo. rhEpo-RBCs stimulate the erythropoiesis of polycythaemic mice in a linear dose-radio-iron incorporation response relationship. These results suggest that rhEpo-RBCs may behave as an alternative to the administration of free rhEpo in the clinical field.

Erythrocytes as carriers for recombinant human erythropoietin

PURPOSE

The aim of this work was to encapsulate recombinant human erythropoietin (rHuEpo) in human and mouse red blood cells (RBCs) to improve the stability of encapsulated rHuEpo.

METHODS

The encapsulation of rHuEpo was achieved by an hypotonic dialysis-isotonic resealing procedure. A radioimmunoassay method was used for the estimation of rHuEpo. The hypoosmotic resistance of carrier erytrhocytes was studied by osmotic fragility measurements. Cell morphology was observed under scanning electron microscopy. Encapsulated rHuEpo was identified by an immunogold labeling assay.

RESULTS

Encapsulation yields were 22% for human RBCs and 14% for mouse RBCs. Cell recovery was around 70%. Carrier-RBCs exhibited a tendency to spherocytic morphology, and showed the typical higher hypoosmotic resistance than normal RBCs. The presence of rHuEpo inside carrier RBCs was identified. The stability of encapsulated rHuEpo seems to be related to the experimental conditions used during the encapsulation procedure. An increase with time of released rHuEpo was observed in carrier-RBC suspensions.

CONCLUSIONS

The encapsulation of rHuEpo in RBCs has been achieved for the first time. These carrier RBC-preparations may serve as an alternative sustained cell delivery system for the in vivo administration of rHuEpo.

Alteration of cyclosporin-A pharmacokinetics after experimental spinal cord injury

The pharmacokinetics of the immunosuppressive agent cyclosporin-A (CsA) were studied in rats submitted to spinal cord (SC) injury. A single CsA 10 mg/kg dose was given either intraperitoneally (i.p.) or orally to rats submitted to experimental SC injury at the T8 level. Twenty four hours after lesion (acute stage of SC injury) i.p. CsA bioavailability was increased, while t1/2 was prolonged. However, oral bioavailability was reduced. Seven weeks after lesion (chronic stage of SC injury) CsA bioavailability, by either route, was not significantly different from control values. Results indicate that parenteral CsA bioavailability is increased during the acute stage of SC lesion, probably due to an impaired elimination. Oral bioavailability, however, is decreased, since there is also an important reduction in gastrointestinal CsA absorption that overrides the effect of impaired elimination. Alterations in CsA pharmacokinetics appear to revert during the chronic stage of SC injury. Changes in CsA bioavailability, depending on the route of administration and on time, must be considered to design an adequate immunosuppressive treatment in SC injury.

Pharmacokinetics of conventional formulation versus fat emulsion formulation of amphotericin B in a group of patients with neutropenia

The pharmacokinetics of amphotericin B administered in a conventional 5% dextrose (glucose) (5% D) solution and in a 20% fat emulsion formulation (Intralipid; 20% IL) were compared in 16 patients (mean age, 42 years [range, 18 to 70 years]) who had been hospitalized for hematological malignancies and with proven or suspected fungal infections. All of the patients received 50 mg (approximately 1 mg/kg of body weight per day) of amphotericin B daily in random order, either as a 50-ml lipid emulsion (20% IL) (group I) or in 500 ml of 5% D (group II). Five serum samples were taken during the 24 h after drug administration, and the levels of amphotericin B were measured by high-pressure liquid chromatography. Serum amphotericin B concentrations declined rapidly during the first 6 h, and subsequent measurements revealed a slow terminal elimination phase in both groups. The maximum serum amphotericin B concentration was significantly lower when the drug was administered in 20% IL (1.46 +/- 0.61 versus 2.83 +/- 1.17 micrograms/ml; P = 0.02). The area under the concentration-time curve from 0 to 24 h was also much lower in group I (17.22 +/- 11.15 versus 28.98 +/- 15.46 micrograms.h/ml). The half-life of the distribution phase was approximately three times longer in group I (2.92 +/- 2.34 h versus 0.64 +/- 0.24 h; P = 0.011). Conversely, the half-lives of the elimination phase were approximately equal in the two groups (11.44 +/- 5.18 versus 15.23 +/- 5.25 h). The mean residence times were also similar in both groups (19.41 +/- 11.13 versus 19.65 +/- 7.86 h). The clearance and the steady-state volume of distribution of amphotericin B in group I were about twice as great as those in group II (62.97 +/- 35.51 versus 33.01 +/- 14.33 ml/kg/h and 1,043.92 +/- 512.10 versus 562.32 +/- 152.05 ml/kg [P = 0.034], respectively). Finally, the volume of distribution in the central compartment was greater in group I than in group II (618.17 +/- 231.80 versus 328.19 +/- 151.71 ml/kg; P = 0.013), but there were no differences in the volume of distribution in the peripheral compartment (425.75 +/- 352.87 versus 234.14 +/- 75.92 ml/kg). These results suggest that amphotericin B has a different pharmacokinetic profile when it is administered in 20% IL than when it is administered in the standard 5% D form and that the main difference is due to a clear-cut difference in the steady-state volume of distribution, especially that in the central compartment.

Impairment by cyclosporin A of reperfusion-induced arrhythmias

This study introduces the immunosuppressor, cyclosporin A, as a cardioprotective drug. This effect was analyzed during development of reperfusion/induced arrhythmias after 5-min period of coronary ligation in hearts of rats under anesthesia. The results indicate that cyclosporin, when given before coronary occlusion, at a dose of 20 mg/kg, effectively protects against the high incidence of arrhythmias and the fall in blood pressure induced by reperfusion. In addition, in inhibits the delivery of lactic dehydrogenase and creatine kinase enzymes to the plasma. We propose that the protective effect could be related with its well documented action to restrain Ca(2+)-induced damage of mitochondrial functions.