Effect of sandblasting on fracture load of titanium ceramic crowns

Purpose of the Study:

It is difficult to achieve a reliable bond between the titanium and veneering porcelain. The aim of this study was to evaluate the bond strength between titanium ceramic crowns.

Materials and Methods:

The surfaces of titanium copings were divided in two groups. Group A sandblasted with 250 um (n = 10) and Group B without sandblasting (n = 10). Low-fusing porcelain was bonded over copings. A universal testing machine was used to determine the fracture load (N) of the crowns. All data were compared using Student''s t-test.

Results:

There was a significant difference in fracture toughness between two groups (P = 0.05). The mean value of fracture strength for Group A was 721.66 N and for Group B was 396.39 N.

Conclusions:

Sandblasting improves the bond strength between titanium, and ceramic, mechanical bonding plays a crucial role in the bonding between titanium and ceramic.Key Words: Bonding, fracture load, sandblasting, titanium     

Self-reported hypoglycaemia in insulin-treated patients with diabetes mellitus: results from the Singapore cohort of the International Operations Hypoglycaemia Assessment Tool study

INTRODUCTIONHypoglycaemia constitutes a significant barrier to achieving glycaemic control with insulin in both Type 1 (T1DM) and Type 2 diabetes mellitus (T2DM). The International Operations Hypoglycaemia Assessment Tool (IO HAT) study was designed to determine the incidence of hypoglycaemia in insulin-treated patients with T1DM and T2DM.METHODSThe IO HAT study retrospectively and prospectively assessed the incidence of hypoglycaemia in patients with insulin-treated diabetes mellitus in nine countries. This sub-analysis included patients from Singapore with T1DM or T2DM who were aged ≥ 21 years and had completed two self-assessment questionnaires (SAQ1 and SAQ2).RESULTSOf the 50 T1DM and 320 T2DM patients who completed the SAQ1, 39 T1DM and 265 T2DM patients completed SAQ2; 100% and 90.9%, respectively, experienced at least one hypoglycaemic event prospectively. The incidence rates of any hypoglycaemia were 49.5 events per patient-year (EPPY) and 16.1 EPPY for T1DM and T2DM patients, respectively, in the four-week prospective period. Hypoglycaemia rate did not differ in terms of glycated haemoglobin level. The vast majority of T1DM or T2DM patients (92.0% and 90.7%, respectively) knew the overall definition of hypoglycaemia before study participation, although over half of the patients (T1DM 54.0%, T2DM 51.9%) defined hypoglycaemia based only on symptoms.CONCLUSIONHigh proportions of insulin-treated patients with diabetes mellitus in Singapore reported hypoglycaemic events prospectively, showing that they had underreported hypoglycaemic episodes retrospectively. Patient education can help in improving hypoglycaemia awareness and its management in the region.     

Current concepts in combination antibiotic therapy for critically ill patients

Widespread emergence of multidrug resistant (MDR) bacterial pathogens is a problem of global dimension. MDR infections are difficult to treat and frequently associated with high mortality. More than one antibiotic is commonly used to treat such infections, but scientific evidence does not favor use of combination therapy in most cases. However, there are certain subgroups where combination therapy may be beneficial, e.g. sepsis due to carbapenem-resistant Enterobacteriaceae (CRE), bacteremic pneumococcal pneumonia, and patients with multiple organ failure. Well-designed prospective studies are needed to clearly define the role of combination therapy in these subgroups.     

Searching for the initiating site of the major capsid protein to generate virus-like particles for a novel laboratory mouse papillomavirus

Correctly folded virus-like particles (VLPs) of papillomavirus (PV) display conformationally dependent epitopes that are type specific, maintained on authentic virions, and induce neutralizing antibodies. Alignment of the L1 amino acid (aa) sequences of 84 PVs revealed that the lengths of their N-termini are diverse and that multiple, possible initiation methionine (met) codons exist. The L1 gene of MusPV (MmuPV1), that naturally infects immunodeficient laboratory mouse strain (NMRI-Foxn1^nu/Foxn1^nu), has four met codons at the 1st, 2nd, 28th, and 30th aas from its N-terminus. Of these, the 3rd and 4th mets, that are at the 28th and 30th aa position from the N-termius, respectively, are located at the position where most PVs have their first met. These two mets, located at the 9th and 11th from the YLPP conserved aas of most PVs, should be considered as consensus initiation codons of PV L1s. Three L1 proteins of MusPV, starting from the 2nd, 3rd, and 4th mets, were expressed using a baculovirus expression system and characterized for their ability to self-assemble into VLPs. While MusPV L1 proteins starting from the 2nd met expressed an L1 protein that did not fold into VLPs, the L1s starting from the 3rd and 4th mets generated correct VLPs in abundant quantities. We now conclude that the highest quantity and best quality VLPs are made from the consensus L1 met of MusPV.     

Ventricular tachycardia due to perinatal asphyxia

Background

Perinatal asphyxia is known to precipitate myocardial dysfunction, rhythm abnormalities and congestive cardiac failure.

Case characteristics

A 2-day old neonate with perinatal asphyxia.

Observation

He developed shock secondary to ventricular tachycardia, and required synchronized cardioversion for reversion of abnormal rhythm.

Outcome

Reversal of arrhythmia leading to recovery.

Message

Early identification and management of ventricular tachycardia in neonate with perinatal asphyxia can be lifesaving.     

Design,Development, and Evaluation of a Novel Microneedle Array-based Continuous Glucose Monitor

The development of accurate, minimally invasive continuous glucose monitoring (CGM) devices has been the subject of much work by several groups, as it is believed that a less invasive and more user-friendly device will result in greater adoption of CGM by persons with insulin-dependent diabetes. This article presents the results of preliminary clinical studies in subjects with diabetes of a novel prototype microneedle-based continuous glucose monitor. In this device, an array of tiny hollow microneedles is applied into the epidermis from where glucose in interstitial fluid (ISF) is transported via passive diffusion to an amperometric glucose sensor external to the body. Comparison of 1396 paired device glucose measurements and fingerstick blood glucose readings for up to 72-hour wear in 10 diabetic subjects shows the device to be accurate and well tolerated by the subjects. Overall mean absolute relative difference (MARD) is 15% with 98.4% of paired points in the A+B region of the Clarke error grid. The prototype device has demonstrated clinically accurate glucose readings over 72 hours, the first time a microneedle-based device has achieved such performance.     

Anti-IL-7 receptor-α reverses established type 1 diabetes in nonobese diabetic mice by modulating effector T-cell function

Genetic variation in the IL-7 receptor-α (IL-7R) gene is associated with susceptibility to human type 1 diabetes (T1D). Here we investigate the therapeutic efficacy and mechanism of IL-7Rα antibody in a mouse model of T1D. IL-7Rα antibody induces durable, complete remission in newly onset diabetic mice after only two to three injections. IL-7 increases, whereas IL-7Rα antibody therapy reduces, the IFN-γ-producing CD4(+) (T(H)1) and IFN-γ-producing CD8(+) T cells. Conversely, IL-7 decreases and IL-7Rα antibody enhances the inhibitory receptor Programmed Death 1 (PD-1) expression in the effector T cells. Programmed Death 1 blockade reversed the immune tolerance mediated by the IL-7Rα antibody therapy. Furthermore, IL-7Rα antibody therapy increases the frequency of regulatory T cells without affecting their suppressor activity. The durable efficacy and the multipronged tolerogenic mechanisms of IL-7Rα antibody therapy suggest a unique disease-modifying approach to T1D.