Effect of time-activity patterns and microenvironments on the personal exposure of undergraduate students to black carbon.

In this study, the personal exposure to and potential dose of black carbon (BC) of undergraduate students (22-27 years old, nonsmokers) were determined. BC was continuously measured by a portable device (microAeth® AE51) for four consecutive days in Istanbul between April and May 2019. The time-activity diaries filled out by each volunteer were assessed to define the activities and microenvironments (home, school, transportation and entertainment) that contributed to daily BC exposure. The overall mean concentration of BC was 2.0 µg/m3, and the mean concentrations on weekdays and weekends were 3.0 µg/m3 and 1.1 µg/m3, respectively. Transportation made the highest contribution to mean BC exposure (42%) and dose (45.8%) on weekdays, while the contributions of home-based activities to BC exposure (66.1%) and dose (63.2%) were higher on weekends. Students had the most intense exposure to (2.8% and 4.6%) and dose (3.1% and 5.8%) of BC in transportation both on weekdays and on weekends, respectively. Between transportation modes, the mean BC concentration was the highest for minibuses (14.8 µg/m3), while walking made the largest contribution to BC exposure (16.8%) on weekdays. Students spent 12.8% of their weekdays at school, and the contributions of the school environment to BC exposure and dose were 8.5% and 7%, respectively. Exposure to BC increased during cooking and eating activities in microenvironments such as the kitchen, cafe and dining hall.

Cisterna chyli: An important landmark in laparoscopic paraaortic lymphadenectomy.

OBJECTIVE: Cisterna chyli is a pearl-shaped elongated lymphatic structure located at the level of L1-L2 vertebra just beneath the aorta (Hsu and Itkin, 2016 [1]). It receives lymphatic drainage of intestines and lower body structures (Loukas et al., 2007 [2]). Size, shape and location are all highly variable and in some autopsy series CC was identified in only half of the cases (Song, 2016 [3]). During the laparoscopic paraaortic lymphadenectomy inadvertent injury to otherwise unidentified CC could lead to refractory chylous ascites (Favero et al., 2010 [4]). The objective of this video is to demonstrate the anatomic localization and consequences of inadvertent injury to CC in laparoscopic paraaortic lymphadenectomy. METHODS: Two different patients undergoing laparoscopic paraaortic lymphadenectomy were presented. RESULTS: The first case is a 51 year old woman with grade III endometrioid adenocarcinoma of uterus who was subjected to laparoscopic staging (laparoscopic hysterectomy + BSO + pelvic and paraaortic lymphadenectomy). Intraoperatively an injury to cisterna chyli occurred which was sealed and repaired immediately. The second case is a woman with stage IIB clear cell cervical cancer undergoing laparoscopic staging (pelvic and paraaortic lymphadenectomy). In this case cisterna chyli could be recognized and preserved. CONCLUSION: Cisterna chyli is an important anatomic structure which should be identified and preserved during laparoscopic paraaortic lymphadenectomy. Any iatrogenic injury to cisterna chyli could lead to chylous ascites and indeed in minority of these cases surgical intervention is required.

Comparison of different glomerular filtration methods in the elderly: which formula provides better estimates?

OBJECTIVES: Technetium-99m diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) is an ideal radioisotopic method having a high correlation with inulin clearance for the determination of glomerular filtration rate (GFR). Different formulas like creatinine clearance (CrCl) in 24 h urine samples, Cockroft-Gault formula (CGF), and modification of diet in renal disease (MDRD) are being used to come up with an estimate. In this study, we compared (99m)Tc-DTPA with the formulas mentioned above in an attempt to best identify the method that would yield the nearly ideal GFR estimates in the elderly. MATERIALS AND METHODS: In 76 patients who were admitted to our clinic, we measured 24 h urine volume (V), urine creatinine (Ucr), and serum creatinine (Scr) levels together with CrCl, Scr, serum urea (Su), and albumin (Alb) levels. By using coefficients identified for age, gender, and race, we calculated modification of diet in renal disease 1 (MDRD1). Different from MDRD1, we calculated modification of diet in renal disease 2 (MDRD2) that does not include Su and Alb parameters and formulas like CGF that include Scr, age, gender, and weight parameters to come up with GFR levels. All patients underwent (99m)Tc-DTPA procedure. RESULTS: The mean of the GFR values measured by (99m)Tc-DTPA was 54.3 ± 19.9. The means of GFR values calculated by CrCl, MDRD1, MDRD2, and CGF were 58.0 ± 30.5, 60.9 ± 22.1, 54.4 ± 20.1, and 57.9 ± 22.4, respectively. GFR as measured by (99m)Tc-DTPA showed statistically significant correlations with the results of other methods (p < 0.001 for all methods). The most significant correlation was with MDRD1. CONCLUSION: MDRD1 can be used for next to ideal and accurate predictions of GFR in the elderly in the daily practice.

Existence of SARS-CoV-2 RNA on ambient particulate matter samples: A nationwide study in Turkey.

Coronavirus disease 2019 (COVID-19) is caused by the SARS-CoV-2 virus and has been affecting the world since the end of 2019. The disease led to significant mortality and morbidity in Turkey, since the first case was reported on March 11th, 2020. Studies suggest a positive association between air pollution and SARS-CoV-2 infection. The aim of the present study was to investigate the role of ambient particulate matters (PM), as potential carriers for SARS-CoV-2. Ambient PM samples in various size ranges were collected from 13 sites including urban and urban-background locations and hospital gardens in 10 cities across Turkey between 13th of May and 14th of June 2020 to investigate the possible presence of SARS-CoV-2 RNA on ambient PM. A total of 203 daily samples (TSP, n = 80; PM2.5, n = 33; PM2.5-10, n = 23; PM10µm, n = 19; and 6 size segregated PM, n = 48) were collected using various samplers. The N1 gene and RdRP gene expressions were analyzed for the presence of SARS-CoV-2, as suggested by the Centers for Disease Control and Prevention (CDC). According to real time (RT)-PCR and three-dimensional (3D) digital (d) PCR analysis, dual RdRP and N1 gene positivity were detected in 20 (9.8%) samples. Ambient PM-bound SARS-CoV-2 was analyzed quantitatively and the air concentrations of the virus ranged from 0.1 copies/m3 to 23 copies/m3. The highest percentages of virus detection on PM samples were from hospital gardens in Tekirdag, Zonguldak, and Istanbul, especially in PM2.5 mode. Findings of this study have suggested that SARS-CoV-2 may be transported by ambient particles, especially at sites close to the infection hot-spots. However, whether this has an impact on the spread of the virus infection remains to be determined.

Assessment of the health risk related to exposure to ultrafine, fine, and total particulates and metals in a metal finishing plant.

The materials and byproducts of the processes used in the metal finishing industry are released as particle contaminants into the air in the workplace. The present study aimed to determine the concentrations and size distributions of these particles and of elements chromium, nickel, copper, manganese, cobalt, and lead (Cr, Ni, Cu, Mn, Co, and Pb, respectively) in a metal finishing industry and evaluate their potential health risks. Particles that are airborne from the dipping baths in the plant were sampled using a Sioutas cascade impactor at five different size fractions (PM>2.5, PM1.0-2.5, PM0.5-1.0, PM0.25-0.5, PM<0.25) and gravimetric analyses were conducted on the sampled filters. The GF-AAS 600 graphite atomic absorption spectrophotometer (PerkinElmer Corporation, Waltham, MA, USA) was used to analyze the elements and the method of USEPA was used to assess the health risk. The ratio of fine particles (PM2.5) to total suspended particles (TSPs) was 0.6. We observed that 50% of TSPs were composed of PM1.0 and that 68-88% of the metals were found in the fine particle fractions. Pb, Cr, and Mn were significantly positively correlated in the PM1.0 fraction, and the highest linear relationship was found between Pb and Cr (r = 0.85, p < 0.01). The total hazard quotient (HQ) for PM2.5 was 1.43, which is higher than the acceptable limit of 1.0. The excess lifetime cancer risk (ELCR) for hexavalent chromium (Cr[VI]) in PM2.5 was 6.09 × 10-5 for female workers and 6.54 × 10-5 for male workers, which are higher than the acceptable limit of 1.0 × 10-6, while total ELCRs for female and male workers were 6.21 × 10-5 and 6.21 × 10-5, respectively. The lifetime cancer risk associated with Cr(VI) in Cr electroplating plants should be taken into consideration as a significant health risk for the workers.

Therapeutic Angiogenesis by Autologous Transplantation of Bone Marrow Mononuclear Cells for Buerger's Patients with Retractable Limb Ischaemia: A Preliminary Report.

Bone marrow implantation into ischaemic limbs could enhance angiogenesis by supplying endothelialprogeniter cells and angiogenic cytokinesot factors. We investigated efficacy and safety of autologousimplantation of bonemarrow-mononuclearcells (BMMC)in patients with ischaemic limbs due to Buerger's disease. We commence daciinical study to test cell therapy with autologous BMMC in patients with ischaemic limbs at the University of Ankara School of Medicine. In order for the patients to qualify for BMMC implantation, they should have critical limb ischaemia define das ischaemic rest painin a limb with or without non healing ulcers, should not respond to previous iloprost infusions and smoking cessation six months prior to evaluation and should not be candidates for nonsurgicalor surgical revascularisation. Primaryend points were safety andfeasibility of the treatmentand total healing of the most importantlesion. Secondary endpoints were total relief of rest pain without the need for analgesies,change in peak walkingtime (PWT)at 12 weeks, improvements in ankle-brachial pressure index(ABI), transcutaneous oxygen saturation using pulse oximetry(SaO2),angiographic evidence of newcollatera lvesselformation, tissue perfusion in the affected extremity using Thallium perfusions cintigraphyW. hilepatients(meanage46.7: !: 10.3years)were undergeneraal naesthesiaw, eharvested bonemarrow(519: t 45.5mUfromtheposteridilriacspineA. fterredbloodcell(RBCd) epletiaannd volumereduction using a continuous flow cell separator,we achieved 91% RBC depletian and concentrated /~MMC to a final volume and concentration of 51.5: t io.1 mLand7.04: t 1.9 x ioe7/mL total nucleated cells, respectively W.eimplantedBMMC (mean12.16: t 4.3 x ioe8) within three hours after marrow aspiration by intramuscular injection into the gastrocnemiusmuscle of ischaemic legs. Isotonic saline were injected into the other extremityin as similar fashion as control. 13 Unilateral intramuscular administration of BMMC was not associated with any complications. The primary efficacy end point, total healing of the most importantlesion, was achieved in three patients. All patients were followed up for at least four weeks. The secondary measures; change in PWT(LlPWT)at 12 weeks, total relief of rest pain without the need of analgesics improved in three patjents. These improvements were sustained for 24 weeks in the first two patients. Digital subtraction angiographic studies before and 3 months after the BMMC implantation showed the presence of a new vascular collateral network across the affected arteries in three patients. Preliminary results of the presentedstudy are promising. Thus, bone marrow maybe a potential source of cells for Buerger'spatients with end-stage Iimbischaemia refractory to other medical treatment modalities.