A new COVID-19 prediction scoring model for in-hospital mortality: experiences from Turkey, single center retrospective cohort analysis.

OBJECTIVE: Although many studies reported prognostic factors proceeding to severity of COVID-19 patients, in none of the article a prediction scoring model has been proposed. In this article a new prediction tool is presented in combination of Turkish experience during pandemic. MATERIALS AND METHODS: Laboratory and clinical data of 397 over 798 confirmed COVID-19 patients from Gülhane Training and Research Hospital electronic medical record system were included into this retrospective cohort study between the dates of 23 March to 18 May 2020. Patient demographics, peripheral venous blood parameters, symptoms at admission, in hospital mortality data were collected. Non-survivor and survivor patients were compared to find out a prediction scoring model for mortality. RESULTS: There was 34 [8.56% (95% CI:0.06-0.11)] mortality during study period. Mean age of patients was 57.1±16.7 years. Older age, comorbid diseases, symptoms, such as fever, dyspnea, fatigue and gastrointestinal and WBC, neutrophil, lymphocyte count, C-reactive protein, neutrophil-to-lymphocyte ratio of patients in non-survivors were significantly higher. Univariate analysis demonstrated that OR for prognostic nutritional index (PNI) tertile 1 was 18.57 (95% CI: 4.39-78.65, p<0.05) compared to tertile 2. Performance statistics of prediction scoring method showed 98% positive predictive value for criteria 1. CONCLUSIONS: It is crucial to constitute prognostic clinical and laboratory parameters for faster delineation of patients who are prone to worse prognosis. Suggested prediction scoring method may guide healthcare professional to discriminate severe COVID-19 patients and provide prompt intensive therapies which is highly important due to rapid progression leading to mortality.

The efficacy of platelet-rich plasma gel in MRSA-related surgical wound infection treatment: an experimental study in an animal model.

INTRODUCTION: The wound healing properties of platelet-rich plasma (PRP) gel have been documented in many studies. PRP gel has also become a promising agent for treating surgical site infections. In this study, we investigated the antibacterial activity and wound healing effectiveness of PRP in an animal model of Methicillin-resistant Staphylococcus aureus subsp. aureus (MRSA N315)-contaminated superficial soft tissue wounds. MATERIALS AND METHODS: Subcutaneous wounds in Wistar Albino male rats were created by making two cm midline incisions followed by inoculation of microorganisms. Study groups comprised of Sham (no treatment), PRP alone, MRSA alone, MRSA + PRP, MRSA + Vancomycin, and MRSA + Vancomycin + PRP groups. We inoculated 0.1 mL (3 × 108 CFU/mL) of MRSA in contaminated groups. After 8 days, all rats were killed, wounds were excised and subjected to histopathologic examination, and MRSA counts were determined. RESULTS: MRSA counts in MRSA, MRSA + PRP, MRSA + Vancomycin and MRSA + Vancomycin + PRP groups were 5.1 × 106 (SD ± 0.4) CFU/mL, 4.3 × 106 (SD ± 0.7) CFU/mL, 2.3 × 106 (SD ± 0.3) CFU/mL, 1.1 × 106 (SD ± 0.4) CFU/mL, respectively. The inflammation scores of MRSA + PRP, MRSA + Vancomycin, and MRSA + Vancomycin + PRP groups were significantly lower than the MRSA group. MRSA + Vancomycin + PRP group inflammation score was significantly lower than the MRSA + PRP group. DISCUSSION: All treatment groups were effective in wound healing and decreasing the MRSA counts. MRSA + PRP combined created identical inflammation scores to the PRP group. More in vivo studies are required to corroborate these findings.

Polidocanol (Lauromacrogol 400) has anti-angiogenic effects in vitro and in vivo.

OBJECTIVE: Polidocanol is the most frequently used sclerosant for sclerotherapy all around the world. Our experimental research aims to find out the angiogenic effects of Polidocanol. MATERIALS AND METHODS: Angiogenic activity of polidocanol was examined in vivo in the chick chorioallantoic membrane (CAM) model, cell viability assay (human umbilical vein endothelial cells - HUVECs) and in vitro tube formation assay of HUVECs. RESULTS: In CAM assay, a significant decrease on CAM vessel growth was observed after the application of polidocanol solutions. Vessel growth inhibition was strongly dose-dependent. There was a cytotoxic effect on HUVECs in the presence of polidocanol observed with MTT assay (p < 0.05). In the tube formation assay, statistically significant decrease in tube formation was observed in polidocanol group. It was found that polidocanol had an anti-angiogenic effect (p < 0.05). The results provide evidence that polidocanol decreases angiogenesis and has a cytotoxic effect on ECs. CONCLUSIONS: These results provide evidence that Polidocanol (lauromacrogol 400) have strong anti-angiogenic effects in vitro and in vivo. Further researches needed to reveal early and long-term effects of polidocanol in the human vascular system and new treatment approach as an anti-angiogenic therapy.

New probing and warm-wash-out technique improves early patency rates in arteriovenous fistula surgery.

OBJECTIVE: Arteriovenous fistulas (AVFs) are commonly used during hemodialysis. Early failure of AVFs is quite common with incidence of 43% to 63%. In this study we aimed to describe a novel approach to AVF surgery for improving early patency rates. PATIENTS AND METHODS: Patients were divided into two groups according to use of probing and warm-wash-out technique. Group I consisted of 31 patients with additional probing technique. Group II consisted of 32 patients without additional maneuver. End-to-side anastomosis were used to all patients. Technical success was defined as having palpation of a thrill on fistula. Flow rates of draining vein was measured at 1st hour, 24th hour, 1st week and 3rd week of surgery. SURGICAL TECHNIQUE: Classical maneuvers were performed until end of the anastomosis. At this time, vein lumen was washed by low-dosed heparinized warm fluid, with assistance of a simple catheter. RESULTS: Technical success was similar in both groups at 1st hour and 24th hour, while there were significantly differences between groups at 1st week (p = 0.042) and 3rd week (p = 0.05) assessments. Flow rates were also measured significantly higher in Group I at 1st hour (p = 0.011) and 24th hour (p = 0.016). Flow rates were almost similar in two groups at 1st and 3rd weeks but overall success rate was higher in Group I comparing with Group II (96.8% vs. 81.3%, respectively, p = 0.05). CONCLUSIONS: Probing and warm-wash out technique will simply increase the surgical success and flow rate of draining vein.

In vitro effect of sodium nitrite on platelet aggregation in human platelet rich plasma--preliminary report.

OBJECTIVE: The role of nitrates and nitric oxide on platelet functions has obtained an increasing attention with respect to their potential effects on cardiovascular disorders. In this study we aimed to analyze the effect of sodium nitrite on platelet functions in human platelets. PATIENTS AND METHODS: This in vitro study was designed to show the effect of sodium nitrite on platelet functions in seven healthy volunteers. Blood samples were centrifuged to prepare platelet rich plasma and platelet poor plasma. Platelet rich plasma was diluted with the platelet poor plasma to have a final count of 300,000 ± 25,000 platelets. Platelet rich plasma was incubated with six different increasing doses (from 10 µM to 5 mM) of sodium nitrite for 1 hour at 37°C. Then stimulating agents including collagen (3 µg ml-1), adenosine diphosphate (10 µM), and epinephrine (10 µM) were added to the cuvette. Changes in light transmission were observed for 10 minutes. In addition spontaneous aggregation were performed in control group with all aggregating agents separately. RESULTS: Effect of sodium nitrite on agonist-induced platelet aggregation depends on the concentration of sodium nitrite. Compared with control group, agonist-induced platelet aggregations were significantly suppressed by sodium nitrite at the concentration of 5, 1.0 and 0.5 mM. CONCLUSIONS: Our results suggested that sodium nitrite has inhibitory effects in vitro on platelet aggregation in a dose-dependent manner.

Effects of taurine on contractions of human internal mammary artery: a potassium channel opening action.

OBJECTIVE: Taurine is an abundant amino acid that is widely distributed in human and animal tissues. Pharmacodynamic studies show that taurine has hypotensive and myocardial protective effects. Studies in isolated tissue baths show that taurine relaxes precontracted arteries. This study aimed to show the effects of taurine on human internal mammary artery (IMA) in vitro and to explain the mechanisms of its effects. METHODS: The response in the IMA was recorded isometrically by a force displacement transducer in isolated organ baths. Taurine (20, 40, 80 mM) was added to organ baths after precontraction with KCl (45 mM) or serotonin (5-HT, 30 µM). Taurine-induced relaxations were also tested in the presence of the cyclooxygenase inhibitor indomethacin (10 µM), the nitric oxide synthase inhibitor L-NAME (100 µM), the large conductance Ca2+-activated K+ channel inhibitor tetraethylammonium (TEA, 1 mM), the ATP-sensitive K+ channel inhibitor glibenclamide (GLI, 10 µM), the voltage-sensitive K+ channel inhibitor 4-aminopyridine (4-AP, 1 mM) and the inward rectifier K+ channel inhibitor barium chloride (BaCl2, 30 µM). RESULTS: Taurine did not affect the resting tone of IMA. However, it produced relaxation in the 5-HT and KCl -precontracted preparations. The relaxation to IMA was not affected by GLI, 4-AP, BaCl2, indomethacin and L-NAME. But, TEA inhibited taurine -induced relaxations significantly (p < 0.05). CONCLUSIONS: The preincubation of IMA with taurine antagonized KCl and 5-HT induced contractions in a concentration dependent manner, while it did not affect the resting tone. The relaxations to taurine were significantly antagonized by pretreatment with TEA. These results suggest that mechanism of vasodilator effect of taurine in IMA may be the activation of large conductance Ca2+-activated K+ channels.

Local sympathetic stimulation not only have local effects in patients with Raynaud's phenomenon.

OBJECTIVE: Many other organs and system can be affected in the course of Primary Raynaud's Phenomenon (RP). Simultaneously increased vasospasm in the pulmonary vascular bed may likely affect the pulmonary function. Therefore, we investigated the effect of Raynaud's phenomenon on the respiratory functions in this study. PATIENTS AND METHODS: Between March 2014 and December 2014, 30 patients with the diagnosis of PRP more than two years and 32 age-sex matched healthy controls were enrolled into this study. Cold stimulation test (CST) was performed. Pulmonary function test were performed following 30 minutes after CST and spirometric measurements were calculated. RESULTS: There were no statistically significant differences between two groups regarding their demographic and clinical data. Mean duration of symptoms from onset to present was 3.01 ± 1.05 years. Patients with Primary RP had significantly lower FVC and higher FEV1/FVC values compared to the control groups (p = 0.015 and p=0.045, respectively). CONCLUSIONS: We found that statistically significant decrease of FVC values in patients with Primary RP compared to the healthy controls could be a impaired innervation of pulmonary system and a predictor of pulmonary vasospasm and/or pulmonary Raynaud's phenomenon, which may develop in future periods.