Surgical versus non-surgical endodontic re-treatment for periradicular lesions

Background : Though success rates of endodontic initial treatment have been improving over the years, persistence of periapical disease is far from being a rare condition. The most common therapeutical options for the re‐treatment of teeth with periapical pathosis are non‐surgical orthograde treatment and surgical treatment. Selection between alternative treatments should be based on assessment of respective benefits (mainly healing) and risks from studies consistent with a high level of evidence. Objectives : To test the null hypothesis of no difference in outcome between surgical and non‐surgical therapy for endodontic re‐treatment of periradicular lesions. Search strategy : The Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE and EMBASE were searched with appropriate search strategies. Handsearching included eight dental journals. The bibliographies of relevant clinical trials and relevant articles were checked for identifying studies outside the handsearched journals. Seven manufacturers of instruments in the field of endodontics or endodontic surgery or both, as well as the authors of the identified randomized controlled trials (RCTs) were contacted in order to identify unpublished or ongoing RCTs. No language restriction was placed. The last electronic search was conducted on 3rd April 2007. Selection criteria : All RCTs about re‐treatment of teeth with periapical pathosis in which both surgical and non‐surgical approaches were used and having a follow up of at least 1 year were considered for the analysis. Data collection and analysis : A quality assessment of the included RCTs was carried out and the authors were contacted for missing information. We independently extracted the data in duplicate. We followed the Cochrane Oral Health Group's statistical guidelines. Main results : Three RCTs were identified, two of them reporting different data from the same clinical study. The risk of bias was judged as moderate for one study and high for the other one. One hundred and twenty‐six cases were followed up for at least 1 year, and 82 had a follow up of 4 years. At the 1‐year follow up the success rate for surgical treatment was slightly better than non‐surgical (risk ratio (RR) 1.13; 95% confidence interval (CI) 0.98 to 1.30). When the follow up was extended to 4 years (only one RCT made it) the outcome for the two procedures became similar. Authors' conclusions : The finding that healing rates can be higher for cases treated surgically as compared to those treated non‐surgically, at least in the short term, is based on two RCTs only. A single RCT reported that in the medium to long term healing rates for the two procedures are very similar. There is currently scarce evidence for a sound decision making process among alternative treatments for the re‐treatment of a periradicular pathosis. More well‐designed RCTs should be performed with follow up of at least 4 years, and with a consistent sample size, to detect a true difference in the long term between the outcomes of the two alternative treatments, if any exist.     

Blood donation leads to a decrease in natural killer cell activity: a study in normal blood donors and cancer patients

Transfusion-induced immunosuppression has long been known to be beneficial for organ transplantation patients, but recent retrospective studies suggest that blood transfusions may be detrimental for patients with cancer. If autologous blood is used to avoid immunosuppression, the assumption is that the procedure, involving blood donation, is immunologically neutral. In the present study, this assumption was evaluated by monitoring 33 normal blood donors and 16 colorectal cancer patients before and after donation of 1 (500 mL) and 2 units of blood, respectively. The cancer patients belonged to the autologous arm of a randomized trial in which the effects of allogeneic versus autologous blood on cancer prognosis were studied. The patients donated 2 units of blood with an interval of 3 to 4 days between donations. Flow cytometric analysis revealed that blood donation by normal donors and cancer patients had no effect on the proportion of B, T, and natural killer (NK) cells. Only the total number of lymphocytes was significantly decreased in the normal donors on Day 12 after donation. Blood donation had no significant effect on T-cell function assessed by phytohemagglutinin stimulation in normal donors or in cancer patients donating 2 units of blood. A significant depression of NK cell function (88% and 74% of predonation levels) was observed in normal donors on Days 2 and 5 after donation; on Day 12, the activity was again normal. Colorectal cancer patients had a significantly depressed NK cell activity (54% of predonation activity) on Day 12 after the first donation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Nationwide survey of home transfusion practices

BACKGROUND: Limited information exists on home transfusion practices. STUDY DESIGN AND METHODS: In 1995, a survey requesting data for 1994 was sent to 1273 American Association of Blood Banks (AABB) institutional members and 113 non-AABB home health care agencies that provide out-of-hospital transfusions. RESULTS: Of 943 respondents, 102 provide blood to a home transfusion program, 37 provide blood and run a home transfusion program, and 13 run a home transfusion program only, for a total of 152 (16%) with some involvement in home blood transfusions. Most of the 50 respondents with a home transfusion program are licensed by their state and accredited by the Joint Commission on Accreditation of Healthcare Organizations. All respondents have written policies for home transfusion, and 90 percent require a signed informed-consent document before initiating transfusions in the home. Most have policies requiring that there be a second adult and a telephone in the home, that the home be deemed safe for transfusion, that the patient's physician be readily available, and that the patient have had prior transfusions. The most common component issued by the blood providers was red cells, followed by platelets. White cell-reduced components were always provided by 36 percent of respondents. The most common patient diagnosis was cancer. Home transfusions were provided primarily by registered nurses. Only 14 percent of respondents indicated that the medical director of the blood bank is responsible for approving a patient for home transfusion. A posttransfusion visit is performed by 46 percent of respondents. CONCLUSION: Although most facilities have policies for the administration of home transfusions, there remains marked heterogeneity among blood providers and transfusionists regarding home transfusion practices.     

Normalization of enhanced hepatic gluconeogenesis by the antiglucocorticoid RU 38486 in acutely uraemic rats

Hepatic amino acid uptake, urea and glucose production are increased in acute uraemia. It has been shown that this metabolic pattern is mediated by glucocorticoids. Accordingly, the administration of the antiglucocorticoid RU 38486 to acutely uraemic rats resulted in a reduction of serum urea-N and glucose levels. To clarify whether this effect is due to a reduction in hepatic gluconeogenesis we examined the effect of the antiglucocorticoid RU 38486 on urea and glucose formation in isolated hepatocytes from sham-operated (SHAM) and bilaterally nephrectomized (BNX) rats receiving RU 38486 or the vehicle only. Hepatic glucose production in BNX rats was considerably increased from Na-pyruvate (+79%), alanine (+174%), glutamine (+158%), and serine (+87%) compared with SHAM animals. Concomitantly, hepatic urea formation was also enhanced from amino acid substrates in acutely uraemic rats. When uraemic animals were treated with RU 38486, glucose production from amino acids and Na-pyruvate was reduced to the range of SHAM animals or even lower. This effect could not be demonstrated in SHAM-operated controls. A comparable decrement in hepatic urea production was observed in BNX rats treated with the antiglucocorticoid. Thus, glucocorticoids appear to play a key role in the abnormal hepatic urea and glucose production of acutely uraemic rats.     

Towards a Smart Non-Invasive Fluid Loss Measurement System

In this article, a smart wireless sensing non-invasive system for estimating the amount of fluid loss, a person experiences while physical activity is presented. The system measures three external body parameters, Heart Rate, Galvanic Skin Response (GSR, or skin conductance), and Skin Temperature. These three parameters are entered into an empirically derived formula along with the user’s body mass index, and estimation for the amount of fluid lost is determined. The core benefit of the developed system is the affluence usage in combining with smart home monitoring systems to care elderly people in ambient assisted living environments as well in automobiles to monitor the body parameters of a motorist.     

Biological evaluation of intervertebral disc cells in different formulations of gellan gum‐based hydrogels

Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd.     

Additional Diagnostic Yield of Adding Serology to PCR in Diagnosing Viral Acute Respiratory Infections in Kenyan Patients 5 Years of Age and Older

The role of serology in the setting of PCR-based diagnosis of acute respiratory infections (ARIs) is unclear. We found that acute- and convalescent-phase paired-sample serologic testing increased the diagnostic yield of naso/oropharyngeal swabs for influenza virus, respiratory syncytial virus (RSV), human metapneumovirus, adenovirus, and parainfluenza viruses beyond PCR by 0.4% to 10.7%. Although still limited for clinical use, serology, along with PCR, can maximize etiologic diagnosis in epidemiologic studies.     

Comparison of thrombin and ristocetin in the interaction between von Willebrand factor and platelets

It is known that the antibiotic ristocetin exposes the platelet membrane receptor for factor VIII/von Willebrand glycoprotein (FVIII/vWF). Recent reports suggest that low concentrations of thrombin also cause platelet membrane receptors to become available for FVIII/vWF. As a consequence, the suspicion has been raised that thrombin provides similar or equivalent activity in vivo to that observed for ristocetin under in vitro conditions. In this study, we quantitated the extent to which thrombin promotes the binding of FVII/vWF to platelets and determined whether or not this interaction initiates or complements platelet aggregation. With ristocetin present, the amount of 125I-FVIII/vWF that became platelet-bound correlated closely with the onset, rate, and extent of platelet aggregation. In contrast, at every thrombin concentration tested, the amount of 125I- FVIII/vWF that specifically bound to platelets was about 6% of that observed with ristocetin. Significantly, FVIII/vWF did not augment the rate of aggregation of platelets in response to thrombin or initiate platelet aggregation when subaggregating doses of thrombin were used. These observations indicate that the minimal association that occurs between FVIII/vWF and the platelet membrane in the presence of thrombin does not correlate with platelet aggregation and therefore is not analogous to the effects of ristocetin. Whether the low level of binding relates to another process, such as platelet-endothelial interactions, remains unknown.     

Autoantibodies inhibit interleukin-7-mediated proliferation and are associated with the age-dependent loss of pre-B cells in autoimmune New Zealand Black Mice

Surface IgM+B220+ B cell precursors can be categorized as either leukosialin (CD43/S7) negative (late stage pre-B cells) or positive (pro-B/early pre-B cells). In autoimmune New Zealand Black (NZB) mice, bone marrow small pre-B cells (IgM-CD43-B220+) and pro-B/early pre-B cells (IgM-CD43+B220+) declined significantly with age. In particular, subpopulations of pro-B/early pre-B cells expressing the heat stable antigen (HSA) were found in lower proportions with age. Significant decreases in interleukin-7 (IL-7) colony forming units (CFU) were also seen in NZB mice by 6 to 8 months of age and accompanied alterations in the numbers of pro-B and pre-B cells in bone marrow. Concomitant with reduced numbers of B lineage precursor cells and IL-7 CFU in vivo, NZB mice produced serum IgM antibodies that strongly inhibited IL-7 CFU responses in vitro. Two monoclonal IgM antibodies (5G9, 2F5) derived from LPS stimulated 10-month-old NZB splenocytes recognized pre-B cell surface antigens on both pre-B cell lines and on IL-7 stimulated bone marrow pro-B/pre-B cells. However, these monoclonal antibodies (MoAb) failed to significantly stain ex vivo bone marrow cells. The 5G9 and 2F5 MoAbs also partially inhibited IL-7 CFU in vitro. These results suggest that NZB bone marrow becomes increasingly deficient in B cell precursors and especially in IL-7 responsive pre-B cells with age. IgM serum antibodies and monoclonal IgM antibodies derived from older NZB mice inhibit pre-B cell growth to IL-7. The production of such autoantibodies may interfere with B cell development in aging NZB mice by preventing IL-7-mediated proliferation.