Near infrared spectrophotometry (cerebral oximetry) in predicting the return of spontaneous circulation in out-of-hospital cardiac arrest

Aim

We assessed out-of-hospital cardiac arrest patients’ cerebral oxygenation during cardiopulmonary resuscitation (CPR) using near infrared spectrophotometry (NIRS). We evaluated the relation between a rise in patients’ cerebral saturation values between the start and end of CPR and return of spontaneous circulation.

Materials and methods

Twenty-three patients with unwitnessed out-of-hospital cardiac arrest and brought to our emergency department by emergency ambulance were evaluated. Cerebral saturations from time of start of CPR were measured using NIRS. CPR was performed for a maximum of 30 min. The relation between cerebral saturations in patients with or without return of spontaneous circulation was then evaluated.

Results

Twenty-three patients, 12 (52.2%) female and 11 (47.8%) male, with a mean age of 64.09 ± 13.66 were included. A correlation was determined between a rise in cerebral saturation measured throughout CPR and the return of spontaneous circulation (P < .001).

Conclusion

Patients whose cerebral saturation values measured with NIRS rise during CPR have a higher post-resuscitation survival rate. Monitoring of patients during CPR with this non-invasive technique may be a good method for predicting return of spontaneous circulation.     

Insulin resistance in type 2 diabetes mellitus may be related to bone mineral density

The mechanism of bone mineral density (BMD) changes in type 2 diabetes mellitus is not clear. We aimed to investigate the effect of insulin resistance in type 2 diabetics on BMD. Insulin resistance was determined using the homeostasis model assessment index (HOMA-IR). Nineteen type 2 diabetic patients with a HOMA-IR <2.7 (mean age, 51.5±9.6yr; body mass index [BMI], 27.3±5.1kg/m(2); duration of diabetes, 10.5±7.3yr) were included in Group A, and 30 BMI- and age-matched type 2 diabetic patients with a HOMA-IR ≥2.7 were included in Group B. The BMD was measured with dual-energy X-ray absorptiometry. Independent t-test was used for statistical analysis. The Group A values for mean fasting glucose and insulin levels were 160.1±77.0mg/dL and 4.79±2.89μU/L, respectively, whereas the Group B values were 195.1±58.9mg/dL (p>0.05) and 19.30±16.89μU/L (p=0.0001). Significantly higher total lumbar vertebra T-score (p=0.02) and total lumbar vertebra BMD in Group A were determined than Group B (p=0.033). The lumbar vertebra total Z-score was significantly lower in Group B (p=0.042). Marked insulin resistance may have a negative effect on BMD in type 2 diabetics, while the presence of hyperinsulinemia may be associated with the low BMD.     

Effect of different disinfectant methods on the initial microtensile bond strength of a self-etch adhesive to dentin

The aim of this in vitro study was to evaluate the effect of different disinfection methods on the initial microtensile bond strength of a two-step, self-etch adhesive to dentin. Twenty mandibular molars were sectioned parallel to the occlusal plane to expose the mid-coronal dentin. All of the teeth were divided into four groups (n = 5 per group): (1) in group OZ, the dentin surfaces were exposed to ozone gas from the Ozonytron X delivery system (OzonyTron X-Bioozonix, Munich, Germany), (2) in group ND, the dentin surfaces were irradiated with an Nd:YAG laser (Pulsmaster 600 IQ, American Dental Technologies, U.S.), (3) in group CHX, the dentin surfaces were treated with a 2% chlorhexidine solution, and (4) in the control group, no treatment was applied. In all of the groups, the teeth were restored with Clearfil SE Bond (Kuraray, Tokyo, Japan) and Clearfil Majesty Posterior (Kuraray, Tokyo, Japan), according to the manufacturer's instructions. The teeth were sectioned perpendicular to the bonded surface (surface area of approximately 1 mm(2)). Thus, six to seven specimens were obtained from each tooth, and a total of 34 specimens were analyzed in each group. The specimens were attached to the microtensile test machine (Micro Tensile Tester, T-61010 K, Bisco, U.S.). The data was analyzed using the one-way analysis of variance (ANOVA) and Tukey test (p < 0.05). Fracture modes of each specimen were determined using a stereomicroscope (SZ-PT Olympus, Tokyo, Japan) and a scanning electron microscope (SEM). The lowest bond strength occurred in the OZ group. Significant differences were determined only between group OZ and the other groups (group ND, group CHX, and control group) (p < 0.05). In conclusion, although ozone decreased the microtensile bond strength of the self-etch adhesive system to dentin, the Nd:YAG laser and 2% chlorhexidine did not change the microtensile bond strength so in context of the present study it would appear that the Nd:YAG laser and 2% chlorhexidine may be used as pre-restorative sterilization procedures on the dentin prior to the application of a two-step, self-etch adhesive.     

Selenium has a protective effect on ischemia/reperfusion injury in a rat ovary model: biochemical and histopathologic evaluation

Background/PurposeThe aim of the study was to evaluate the effects of selenium (Se) on ischemia/reperfusion (I/R) injury in rat ovaries.MethodsThirty-five female Sprague-Dawley rats were randomly divided into 5 groups (n = 7): sham (S), I/R1, I/R2, Se1, and Se2. In the I/R1 and Se1 groups, 4 hours of ischemia was followed by 6 hours of reperfusion, and in the I/R2 and Se2 groups, 4 hours of ischemia was followed by 12 hours of reperfusion. In the Se groups, 30 minutes before reperfusion, a single dose of 0.2 mg/kg Se was administered intraperitoneally. The ovarian tissue levels of malondialdehyde (MDA) and nitric oxide (NO), and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were measured biochemically. Tissue damage to ovarian tissue was scored by histopathologic examination.ResultsThe I/R groups had significantly higher MDA levels and lower CAT, SOD, and GPx activities than the sham group (P < .05). Although NO levels were significantly higher in the I/R1 group than in the sham group (P < .05), the NO levels in the I/R2 and sham groups were similar. Selenium pretreatment significantly lowered tissue MDA and NO levels and increased tissue SOD and GPx activities in the Se groups, compared with those in the I/R groups (P < .05). Catalase activities were significantly higher in the Se2 group than in the I/R2 group (P < .05). Catalase activities were higher in the Se1 group than in the I/R1 group, but the difference was not statistically significant. Treatment with Se significantly decreased the ovarian tissue damage scores in the Se2 group compared with those in the I/R2 group (P < .05).ConclusionSelenium is effective in preventing tissue damage induced by I/R in rat ovaries.     

Stroke Mechanism in COVID-19 Infection: A Prospective Case-Control Study

BackgroundThe characteristics and pathophysiological mechanisms involved in acute ischemic stroke in patients with COVID-19 infection have not been fully clarified. We prospectively studied the phenotypic and etiological features of acute stroke occurring in COVID-19 infection.Patients & methodsWithin nine months starting from April-2020, the presence of COVID-19 infection was determined by thoracic CT and SARS-CoV-2 PCR in all acute stroke cases managed in a single tertiary center. Consecutive and prospective data on vascular risk factors/comorbidities, in-hospital quality metrics, discharge outcomes, etiological subclassification and blood markers of thrombosis / inflammation were compared in 44 COVID-19 positive cases (37 acute ischemic stroke, 5 TIA, 2 intracerebral hematoma) and 509 COVID-19 negative patients (355 ischemic, 105 TIA, 44 hematoma and 5 stroke mimic).ResultsCOVID-19 positive patients had more severe strokes, delayed hospital admission, longer hospital stay, higher mortality rates, but had similar vascular risk factors/comorbidities frequency, thrombolysis/thrombectomy utilization rates, metrics, and stroke etiological subtype. They had significantly higher CRP, fibrinogen, ferritin, leukocyte count and lower lymphocyte count. No difference was detected in aPTT, INR, D-dimer, platelet, hemoglobin, homocysteine levels and ANA, anti-dsDNA antibody and ENA panel positivity rates. Anti-phospholipid antibodies have been studied in 70% of COVID-19 positive and all cryptogenic patients, but were never found positive. Tests for coagulation factor levels and hereditary thrombophilia did not show major thrombophilia in any of the stroke patients with COVID-19.ConclusionWe documented that there is no significant difference in etiological spectrum in acute stroke patients with COVID-19 infection. In addition, cryptogenic stroke and antiphospholipid antibody positivity rates did not increase.     

3D-printed poly(lactic acid) scaffolds for trabecular bone repair and regeneration: scaffold and native bone characterization

Purpose: Study objectives were set to (i) fabricate 3D-printed scaffolds/grafts with varying pore sizes, (ii) characterize surface and mechanical properties of scaffolds, (iii) characterize biomechanical properties of bovine trabecular bone, and (iv) evaluate attachment and proliferation of human bone marrow mesenchymal stem cells on 3D-printed scaffolds.

Materials and Methods: Poly(lactic acid) scaffolds were fabricated using 3D-printing technology, and characterized in terms of their surface as well as compressive mechanical properties. Trabecular bone specimens were obtained from bovine and characterized biomechanically under compression. Human bone marrow mesenchymal stem cells were seeded on the scaffolds, and their attachment capacity and proliferation were evaluated.

Results: Contact angles and compressive moduli of scaffolds decreased with increasing pore dimensions of 0.5 mm, 1.0 mm, and 1.25 mm. Biomechanical characterization of trabecular bone yielded higher modulus values as compared to scaffolds with all pore sizes studied. Human bone marrow mesenchymal stem cells attached to the surfaces of all scaffolds yet proliferated more on scaffolds with 1.25 mm pore size.

Conclusions: Collectively, given the similarity between 3D-printed scaffolds and native bone in terms of pore size, porosity, and appropriate mechanical properties of scaffolds, the 3D-printed poly(lactic acid) (PLA) scaffolds of this study appear as candidate substitutes for bone repair and regeneration.     

Evaluation of periodontal status and cytokine/chemokine profile of GCF in patients with severe congenital neutropenia

Severe congenital neutropenia (SCN) is a primary immunodeficiency characterized by defect in neutrophil count. Increased risk of infections in addition to periodontal problems, such as ulcerations of oral mucosa, gingival inflammation, and rapid loss of attachment are common in the course of the disease. The aim of the present study is to define the causal relationship between the severity of periodontal inflammation and severe congenital neutropenia through identification of cytokine profile in gingival crevicular fluid (GCF). A case–control study was performed in patients diagnosed with SCN and healthy controls. Demographic data, the molecular defect, laboratory work-up were gathered from the hospital registry. Periodontal indices were recorded and GCF samples were analyzed using multiplex analysis for the simultaneous measurements of the particular cytokines and chemokines. The present study included 14 patients and 22 control subjects. Both groups were comparable in terms of age and sex. Severity of gingival inflammation measured by the criteria of Löe was higher in the SCN cases (p < 0.05). Moreover, GCF levels of IFN-α, TNF-α, IL-10, IL-13, IL-15, IL-17, IL-2, IL-7, IL-33, IP-10, MIG, MIP-1β were significantly higher in the controls. Decreased cytokine secretion seems to correlate with the decrease in neutrophil counts. The severity of gingival inflammation in SCN patients may be due to the bacterial overgrowth and the change in the content of the oral flora due to the decreased neutrophil counts. Therefore, regular periodontal examinations, the motivation of oral hygiene as well as the compliance with therapy in SCN patients contribute to the periodontal health.

     

Rabbit Antithymocyte Globulin Treatment in Childhood Acquired Severe Aplastic Anemia

Acquired severe aplastic anemia (SAA) is a life threatening bone marrow failure characterized by pancytopenia and hypocellular bone marrow. Matched sibling donor is not available for majority of the patients and many children receive immunosuppressive therapy (IST). Although horse antithymocyte globuline (ATG) is the preferred option, our patients received rabbit ATG; since horse ATG is not available in Turkey. We reviewed the medical records of children with SAA who were treated with rabbit ATG, cyclosporine, and granulocyte colony stimulating factor (GCSF) between 2006 and 2012. Fifteen children with SAA aged between 1.5 and 17 years received rabbit ATG as first line treatment. Only two of them showed partial response and the others did not give any response at 3rd, 6th, and 12th months after the first course of IST. The second course of ATG was given to 8 of the patients; Rabbit ATG at the same dosage was used for 3 of them, and others were given horse ATG. None of the patients responded to the second course of ATG. Invasive fungal infection (IFI) which was seen in 80% of the patients was the most significant problem. Overall survival rate was 60%. The median time between the diagnosis and initiation of IST was 57 (range; 29–144) days. This delay might be significantly contributed to unresponsiveness. In our series, the use of rabbit ATG was not effective for these patients as first line treatment modality. Response rate was very low and the incidence of fungal infections was very high in the SAA patients who received rabbit ATG.