Comparing the effects of root surface scaling with ultrasound instruments and Er,Cr:YSGG laser

There are several studies done to show the comparability of laser scaling and root planing with routine methods. The most suitable wavelengths for such an application are reported as 2,940 and 2,780 nm. The superficial interactions of the current wavelength with root surface is investigated in this study to compare the crater and crack formation during the procedures between ultrasound and Er,Cr:yttrium-scandium-gallium garnet (YSGG; 2,780 nm) laser-treated teeth. Thirty human teeth with calculus on their root surface, which were extracted because of the severe periodontitis, were selected for this interventional in vitro study. Calculus area were divided into two equal parts: One of them was prepared for Er,Cr:YSGG (Biolase, Waterlase, USA) laser irradiation and the other one for ultrasound treatment (Dentsply cavitron, DENTSPLY International, USA). The Er,Cr:YSGG laser was specified as follows: pulse energy = 50 mJ, power = 1 W, wavelength = 2,780 nm, pulse repetition rate = 20 pulse per seconds, tip length = 6 mm, and tip diameter = 600 microm. Nineteen of the laser samples (95%) and eight of ultrasound ones (40%) out of 20 samples in each group had craters showing a statistical significant difference (p < 0.001). The number and depth of these craters are also evaluated. Thirteen samples of the laser cases (65%) and all samples of the ultrasound group showed cracks with significant differences (p = 0.008). In addition, the number and width of cracks in both groups are reported. As a general conclusion, the laser-treated samples show more craters but less cracks.     

Interleukin 18 binding protein (IL18-BP) inhibits neointimal hyperplasia after balloon injury in an atherosclerotic rabbit model

OBJECTIVES: Interleukin 18 (IL18) is an interferon (IFN)-gamma-inducing factor and a proinflammatory and proatherogenic cytokine. IL18 binding protein (IL18-BP) functions as an IL18 inhibitor. This study was designed to investigate whether systemic administration of IL18-BP could inhibit neointimal hyperplasia and arterial lipid deposition. METHODS: New Zealand white, male rabbits were fed with a 21% fat, 0.15% cholesterol diet. The left superficial femoral artery (SFA) was de-endotheliazed with a 2F arterial embolectomy catheter. IL18-BP (5 microg, 10 microg, or 25 microg), or 0.9% saline (control) was administered by i.v. bolus during surgery. Rabbits were followed-up at 2 and 4 weeks. Intima-media (I/M) and lumen-whole artery (L/A) area ratios, and luminal areas were measured. Serum lipid levels, liver enzymes, and kidney function were evaluated. Inflammatory cells were quantified and further verified with immunohistofluorescence staining. The extent of lipid deposition in the artery wall was quantified with Oil Red O (ORO) staining employing Zeiss AxioVision 4.6.3. Image analysis software. Lipid laden cells including macrophages were evaluated by transmission electron microscopy (TEM). RESULTS: Intravenous IL18-BP 5 microg, 10 microg, and 25 microg significantly reduced I/M ratios compared with the control group at both 2 and 4 weeks. There was no significant difference between the 5 microg and 10 microg dose groups. However, at 10 microg, IL18-BP significantly increased L/A ratio more than either the 5 microg IL18-BP or control groups. The high fat diet caused significant elevation of serum lipids at 4 and 6 weeks. IL18-BP had no effect on blood lipid levels. Lipid deposit in the thoracic aorta of the control group at 6 weeks was more than at 4 weeks (P = .025). Administration of IL18-BP inhibited the lipid deposition at 4 weeks (not significant) and 6 weeks (P = .012 to .008) compared with its control group. Lipid laden macrophages (foam cells), as well as endothelial cells and smooth muscle cells were seen in the descending thoracic aorta after 6 weeks of a high fat diet by ORO, immunohistofluorescence staining, and TEM. The lipid laden cells were not seen in either of IL18-BP groups. IL18-BP 10 microg significantly inhibited mono/macro adherence and infiltration in the SFA after balloon-injury at 2 weeks after surgery. CONCLUSION: A single intravenous dose of IL18-BP significantly decreased arterial neointimal hyperplasia, improved lumen to artery ratio after balloon-injury and also prevented arteriosclerosis progression. CLINICAL RELEVANCE: A single intravenous dose of IL18BP decreased neointimal hyperplasia and improved arterial L/A ratios in an atherosclerotic balloon-injury animal model. These preliminary results suggest that IL18BP may be a promising molecular approach to inhibit neointimal hyperplasia and arteriosclerosis progression following coronary and peripheral angioplasty.     

Imaging data in COVID-19 patients: focused on echocardiographic findings

To assess imaging data in COVID-19 patients and its association with clinical course and survival and 86 consecutive patients (52 males, 34 females, mean age?=?58.8 year) with documented COVID-19 infection were included. Seventy-eight patients (91%) were in severe stage of the disease. All patients underwent transthoracic echocardiography. Mean LVEF was 48.1% and mean estimated systolic pulmonary artery pressure (sPAP) was 27.9 mmHg. LV diastolic dysfunction was mildly abnormal in 49 patients (57.6%) and moderately abnormal in 7 cases (8.2%). Pericardial effusion was present in 5/86 (minimal in size in 3 cases and mild- moderate in 2). In 32/86 cases (37.2%), the severity of infection progressed from “severe” to “critical”. Eleven patients (12.8%) died. sPAP and computed tomography score were associated with disease progression (P value?=?0.002, 0.002 respectively). Tricuspid annular plane systolic excursion (TAPSE) was significantly higher in patients with no disease progression compared with those who deteriorated (P value?=?0.005). Pericardial effusion (minimal, mild or moderate) was detected more often in progressive disease (P?=?0.03). sPAP was significantly lower among survivors (P value?=?0.007). Echocardiographic findings (including systolic PAP, TAPSE and pericardial effusion), total CT score may have prognostic and therapeutic implication in COVID-19 patients.

     

Injection of intrathecal normal saline in decreasing postdural puncture headache

Purpose

Postdural puncture headache (PDPH) is the most common and still unresolved postoperative complication of spinal anesthesia. Although there are several positive results of intrathecal saline injection for the treatment of PDPH and prophylaxis after accidental dural puncture, the effect of deliberate intrathecal saline injection before spinal anesthesia has not been examined. The objective of our study was to evaluate the effect of prophylactic administration of intrathecal normal saline in decreasing PDPH.

Methods

One hundred healthy women (ASA physical status I) of age between 18 and 35 years scheduled for elective term cesarean delivery under spinal anesthesia were included. Patients were randomly divided into two equal groups. Group C received 2.5 ml (12.5 mg) hyperbaric bupivacaine 0.5 % as a control, and group S received intrathecal normal saline 5 ml before intrathecal injection of 2.5 ml (12.5 mg) hyperbaric bupivacaine 0.5 %. The incidence and severity of PDPH were assessed after 48 h and again 3–7 days after operation.

Results

Basal characteristics were statistically similar in both groups (P > 0.05). The incidences of moderate and severe PDPH during first postoperative 48 h were not different between the groups (P = 0.24). However, the frequency of PDPH after 3–7 days was statistically higher in group C in compared with group S (16 vs. 2 %, P = 0.03). Totally the frequency of PDPH was higher in group C (24 vs. 2 %, P = 0.002).

Conclusion

Administration of normal saline (5 ml) before intrathecal administration of hyperbaric bupivacaine as a preventive approach is an effective and simple way to minimize PDPH in patients undergoing cesarean section.     

Uric acid stimulates vascular smooth muscle cell proliferation and oxidative stress via the vascular renin-angiotensin system

BACKGROUND: Plasma uric acid has been associated with hypertension in a variety of disorders, and has been shown to be predictive of hypertension. The mechanistic role of uric acid in the development of hypertension is not known however. METHOD: We tested the hypothesis that uric acid stimulates vascular smooth muscle cell (VSMC) proliferation and oxidative stress by stimulating the vascular renin-angiotensin system (RAS). Rat VSMC were exposed to 0-300 micromol uric acid for 48 h. RESULTS: Uric acid (200 and 300 micromol) stimulated the proliferation of VSMC as measured by thymidine uptake. This effect was prevented by 10(-6) mol losartan or by 10(-6) mol captopril. Incubation of VSMC with uric acid for 48 h also increased angiotensinogen messenger RNA expression and intracellular concentrations of angiotensin II. These responses were also inhibited by losartan and captopril. Increased expression of angiotensinogen mRNA was also inhibited by co-incubation with PD 98059, a mitogen-activated protein (MAP) kinase inhibitor. Uric acid stimulated the production of hydrogen peroxide and 8-isoprostane in VSMC. These increases in oxidative stress indicators were significantly reduced by co-incubating the cells with captopril or losartan. Uric acid also decreased nitrite and nitrate concentrations in the culture medium, an effect that was prevented by losartan and captopril. CONCLUSION: These results demonstrate that uric acid stimulates proliferation, angiotensin II production, and oxidative stress in VSMC through tissue RAS. This suggests that uric acid causes cardiovascular disorders by stimulating the vascular RAS, and this stimulation may be mediated by the MAP kinase pathway.     

Effect of a clinical decision support system on adherence to a lower tidal volume mechanical ventilation strategy

Purpose

The purpose of the study was to measure the effect of a computerized decision support system (CDSS) on adherence to tidal volume (V_T) recommendations.

Materials and Methods

We performed a prospective before-after evaluation study on applied V_T to examine the impact of a CDSS on adherence to our local protocol in a 30-bed mixed medical-surgical intensive care unit of a university hospital. All intensive care unit patients who were intubated and mechanically ventilated for at least 1 hour were included.

Results

A total of 3 663 674 V_T records of 696 patients were analyzed. The average volume greater than 6 mL/kg predicted body weight (PBW) and the mean percentage of ventilation time with V_T greater than 6 mL/kg PBW decreased after intervention by 6.0% and 3.4%, respectively (not significant). A stronger effect of the decision support intervention was found among patients with longer duration of mechanical ventilation (>24 hours): for these patients, the average V_T in exceeding 6 mL/kg PBW and the mean percentage of ventilation time with V_T greater than 6 mL/kg PBW decreased after intervention by 18.3% (P = .01) and 9.5% (P = .01), respectively. In this group, the mean percentage of ventilation time with V_T records between 8 and 10, between 10 and 12, and greater than 12 mL/kg PBW decreased by 21.8% (P = .006), 21.5% (P = .047), and 24.7% (P = .155), respectively.

Conclusions

The use of a CDSS, integrated in a patient data management system, improves implementation of a lower V_T mechanical ventilation strategy for patients ventilated for longer than 24 hours.     

The Effect of a Constant Electrical Field on Osseointegration after Immediate Implantation in Dog Mandibles: A Preliminary Study

PURPOSE: The long time span between insertion of implants and functional rehabilitation often inconveniences patients. Accelerating bone growth around dental implants can shorten this time span. This in vivo study evaluated the effect of a constant electrical field on bone growth around dental implants. MATERIALS AND METHODS: Four mongrel dogs were used in this study. Sixteen dental implants were placed immediately after extraction of the first premolar and molar teeth. A constant electrical field (CEF) generator was placed in the mucoperiostal pouch created from the subperiostral dissection under the inferior border of the dog's mandible and connected to the experiment side fixtures. CEF provided 3 V of electrical potential during osseointegration. Histologic sections were stained with hematoxylin-eosin and observed under light microscopy. The sections were analyzed histomorphometrically to calculate the amount of newly formed bone. Statistical analysis was performed with SPSS 11.0 computer software (alpha= 0.05). RESULTS: At the end of the first stage of the osseointegration (90 days) CEF group sections showed enhanced growth of the trabeculae compared with the control group. Statistical analysis revealed significant differences between experimental and control groups. Bone contact ratio was statistically significant in the experimental group (p= 0.001). An increase in the local bone formation and bone contact ratio was observed with direct electrical stimulation of the implant and the bone area around the implant. CONCLUSION: Minimal direct electrical current, which can produce an electrical field around the implant, can increase the amount of bone formation and decrease the time of osseointegration.