p53 regulates a non-apoptotic death induced by ROS

DNA damage induced by reactive oxygen species and several chemotherapeutic agents promotes both p53 and poly (ADP-ribose) polymerase (PARP) activation. p53 activation is well known to regulate apoptotic cell death, whereas robust activation of PARP-1 has been shown to promote a necrotic cell death associated with energetic collapse. Here we identify a novel role for p53 in modulating PARP enzymatic activity to regulate necrotic cell death. In mouse embryonic fibroblasts, human colorectal and human breast cancer cell lines, loss of p53 function promotes resistance to necrotic, PARP-mediated cell death. We therefore demonstrate that p53 can regulate both necrotic and apoptotic cell death, mutations or deletions in this tumor-suppressor protein may be selected by cancer cells to provide not only their resistance to apoptosis but also to necrosis, and explain resistance to chemotherapy and radiation even when it kills via non-apoptotic mechanisms.

Influence of Er:YAG and Ti:sapphire laser irradiation on the microtensile bond strength of several adhesives to dentin

The aim of the present study was to evaluate the influence of erbium:yttrium-aluminum-garnet (Er:YAG) and Ti:sapphire laser irradiation on the microtensile bond strength (MTBS) of three different adhesive systems to dentin. Flat dentin surfaces from 27 molars were divided into three groups according to laser irradiation: control, Er:YAG (2,940 nm, 100 μs, 2.7 W, 9 Hz) and Ti:sapphire laser (795 nm, 120 fs, 1 W, 1 kHz). Each group was divided into three subgroups according to the adhesive system used: two-step total-etching adhesive (Adper Scotchbond 1 XT, from now on XT), two-step self-etching adhesive (Clearfil SE Bond, from now on CSE), and all-in-one self-etching adhesive (Optibond All-in-One, from now on OAO). After 24 h of water storage, beams of section at 1 mm(2) were longitudinally cut from the samples. Each beam underwent traction test in an Instron machine. Fifteen polished dentin specimens were used for the surface morphology analysis by scanning electron microscopy (SEM). Failure modes of representative debonded microbars were SEM-assessed. Data were analyzed by ANOVA, chi-square test, and multiple linear regression (p < 0.05). In the control group, XT obtained higher MTBS than that of laser groups that performed equally. CSE showed higher MTBS without laser than that with laser groups, where Er:YAG attained higher MTBS than ultrashort laser. When OAO was used, MTBS values were equal in the three treatments. CSE obtained the highest MTBS regardless of the surface treatment applied. The Er:YAG and ultrashort laser irradiation reduce the bonding effectiveness when a two-step total-etching adhesive or a two-step self-etching adhesive are used and do not affect their effectiveness when an all-in-one self-etching adhesive is applied.

Comparative validity of the OIDP and OHIP-14 in describing the impact of oral health on quality of life in a cross-sectional study performed in Spanish adults

OBJECTIVES

We aimed to compare the utility and validity of two popular socio-dental indicators (OIDP and OHIP-14) for describing the impact of oral conditions on quality of life applied simultaneously.

STUDY DESIGN

We recruited a consecutive sample of 270 healthy Spanish workers visiting the Employment Risk Prevention Centre for a routine medical check-up. OHIP-14 was self-completed before the oral examination and the face to face interview of the OIDP was performed. Both instruments were compared by evaluating its reliability and its validity.

RESULTS AND CONCLUSIONS

The standardised Cronbach alphas for OHIP-14 and OIDP were 0.89 and 0.74 respectively. OIDP showed lower face validity but higher content validity than OHIP-14. Both indicators showed high construct and criterion validity, since individuals perceiving need for dental treatment or having any complaint about their mouth obtained significantly higher total OIDP and OHIP scores than their counterparts. The prevalence of impacts was much higher using the OHIP (80.7%) than the OIDP (27.8%).

The Discovery of Surgical Anesthesia

The suppression of pain during surgical interventions has been a major achievement for humankind. Chronologically, in 1842, William E. Clarke, a chemist in Rochester (NY), provided Elijah Pope with ether for the purposes of tooth extraction. In 1844, in Boston, G.Q. Colton and the dentist Horace Wells used nitrous oxide as an anesthetic for tooth extraction. On the 16th of October, 1846, the American dentist William T.G. Morton became a pioneer within the medical community with respect to anesthesia by inhalation when he used ether as an anesthetic at the Massachusetts General Hospital. In 1847, the Scot James Young Simpson began to use chloroform as an anesthetic for obstetrics in Edinburgh. These events gave rise to several disputes among their users (who are not very well-known today), who strove to claim that they had been the discoverers of surgical anesthesia, with a view to obtaining a series of patents and state sinecures. This article attempts to clarify certain discrepancies about the authorship of surgical anesthesia. The evidence suggests that surgical anesthesia first began to be applied in the field of dentistry.

[SERV clinical practice guidelines: management of retinal vein occlusion. Sociedad Española de Retina y Vitreo]

PURPOSE

A guidelines for the management of retinal vein occlusion is presented. This is necessary because at this moment several therapeutic alternatives have been developed although their role is not yet sufficiently defined.

METHODS

Review of the literature for evidence published up to date. Relevant literature was identified and the level of evidence graded. Evidence was then assessed for consistency, applicability and clinical impact. The information was contrasted with those guides published in other countries.

RESULTS

Taking into account the different options of treatment that are currently used, several modes of action are suggested. The role of the various complementary examinations are discussed and it is recommended that criteria for the treatment are based on clinical, angiographic, and tomographic findings.

CONCLUSIONS

Although there is no overall consensus, these guidelines promote a good standard of clinical practise and provide an update of the management of retinal vein occlusion.

[Assessment of the efficiency of the clinical management of neuropathic pain in specialist clinics compared to general clinics in neurology health care units in Spain]

OBJECTIVES

To analyse the cost-consequences of chronic neuropathic pain (NeP) outpatients care comparing management in general clinics (GC) versus specialised pain clinics (SPC) in neurology settings in Spain.

METHODS

A 6-month retrospective, cross-sectional, comparative observational study including NeP subjects was designed. Sociodemographics and clinical characteristics of subjects along with pain-related healthcare and non healthcare resources utilization were recorded. Lost-work-days equivalent missed as a consequence of pain were also collected to compute indirect costs. Costs to society were calculated in euros for the year 2008. Severity and interference of pain were used for the main effectiveness evaluation.

RESULTS

A total of 234 patients (53% in SPC), 56.8% women, and 59.3+/-14.7 years were included. Patients were allocated according to usual administrative procedures in each participant centre, consecutively and independently of the diagnosis and clinical status of patients. Yearly indirect costs were euro1,299+/-2,804 in SPC compared to euro1,483+/-3,452 in GC (p=0.660), while annual direct costs were, euro2,911+/-3,335 and euro3,563+/-4,797, respectively (p=0.239), with total costs of euro4,210+/-4,654 and euro5,060+/-6,250, respectively (p=0.249). Mean pain severity at the time of evaluation was 3.8+/-2.3 in subjects in SPC vs. 5.2+/-2 in GC (p<0.001), while the average interference of pain on daily activities were 3.3+/-2 and 4.7+/-2.5, respectively (p<0.001).

CONCLUSIONS

In neurology settings in Spain, the outpatient clinical management of chronic NeP in SPC was a dominant alternative compared with GC healthcare, since it has shown better patients healthcare outcomes with less severity and interference of pain on daily activities, while maintaining a similar level of costs. These results could help health decision makers when planning the use of health care resources.