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1.
Medicine (Baltimore) ; 102(51): e36713, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38134055

RESUMO

Acute kidney damage (AKI) is a common cause of pediatric intensive care unit (PICU) admissions. Implementing a reno-protective strategy for AKI prediction can significantly enhance outcomes. The renal angina index (RAI) is a risk stratification tool used to predict severe AKI. We aim to assess the reliability and accuracy of the RAI scoring system in predicting AKI as compared to other conventional AKI markers. A prospective, observational study was conducted in the PICU of 2 tertiary medical centers in the Middle East. A total of 446 patients, aged 1-month to 14-years, without chronic kidney disease were enrolled. The RAI was calculated using the renal risk and renal injury score within the first 8 to 12 hours of admission. The accuracy of RAI was compared to changes in serum creatinine from baseline. The outcome was assessed on Day 3 for presence of AKI according to the kidney disease improving global outcome (KDIGO) criteria and associated sequelae. A positive RAI (RA+) was defined as RAI readings ≥ 8. Among the patients, 89 (19.9%) had a positive RAI within the first 8 to 12 hours of admission. The RA + group had a significantly higher occurrence of Day 3 severe AKI (KDIGO stages 2&3) compared to the RA- group (60.6% vs 4.2%, P < .001). The RA + group also had a significantly higher utilization of renal replacement therapy (RRT) (21.3% vs 1.1%, P < .001), longer mean PICU length of stay in days (11.1 ±â€…3.5 vs 5.5 ±â€…2.1, P < .001), and increased mortality (31.4% vs 2.8%, P < .001) compared to the RA- group. The RAI score demonstrated superior predictive ability for Day 3 AKI, with a sensitivity of 72%, specificity of 95%, and area under the curve (AUC) of 0.837, compared to changes in serum creatinine from baseline (sensitivity: 65%, specificity: 89%, AUC: 0.773), fluid overload (sensitivity: 43.7%, specificity: 79%, AUC: 0.613), and illness severity scores (sensitivity: 52.4%, specificity: 80.5%, AUC: 0.657). RAI proved to be a reliable and rapid bedside test for identifying critically ill children at risk of developing severe AKI. This enables physicians to implement reno-protective measures and intervene early, thereby improving prognosis.


Assuntos
Injúria Renal Aguda , Estado Terminal , Criança , Humanos , Creatinina , Estudos Prospectivos , Estado Terminal/terapia , Reprodutibilidade dos Testes , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Injúria Renal Aguda/epidemiologia , Angina Pectoris/complicações
2.
Microsc Microanal ; 29(3): 1178-1189, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37749685

RESUMO

Wounds can be a result of surgery, an accident, or other factors. There is still a challenge to find effective topical wound-healing agents. This study aims to investigate the wound-healing activity of chemical and green synthesized chitosan nanoparticles (Ch-NPs) using Lawsonia inermis leaves extract. The nanoparticles were morphologically and chemically characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (HRTEM). Forty-five adult female albino rats were randomly divided into three groups. The cutaneous surgical wounds were topically treated with 0.9% normal saline (control group), green Ch-NPs (second group), and chemical Ch-NPs gels (third group), respectively. The clinical picture of wounds and histopathological changes were assessed on the 3rd, 7th, 14th, and 21st days post-treatment. X-ray diffraction analysis revealed great crystallinity and purity of nanoparticles. The studied nanoparticles increased the wound contraction percent (WC%), reduced healing time and wound surface area (WSA), and these results were backed up by histological findings that indicated improved epithelialization, dermal differentiation, collagen deposition, and angiogenesis in treated rats compared with control rats (p < 0.05). We concluded that the wound-healing effects of the studied nanoparticles are encouraging, and further studies for complete assessment are still needed.


Assuntos
Quitosana , Lawsonia (Planta) , Nanopartículas , Feminino , Animais , Ratos , Cicatrização , Etanol , Extratos Vegetais/farmacologia
3.
J Parasit Dis ; 47(2): 349-362, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37193508

RESUMO

Trapped Schistosoma mansoni eggs trigger fibrotic liver disease that can continue to liver cirrhosis and failure. This work evaluates the outcome of platelet rich plasma (PRP) on S. mansoni-induced liver fibrosis by intraperitoneal (IP) and intrahepatic (IH) routes with/without Praziquantel (PZQ) treatment. Swiss albino mice (n = 162) were divided into non-infected (n = 66) and infected (n = 96) groups, then subdivided into non-treated and treated subgroups with PRP(IP), PRP(IH) 6th and 10th weeks post-infection, PZQ, PZQ + PRP(IP) and PZQ + PRP(IH) 6th and 10th weeks post-infection. Effects of treatments were evaluated by parasitological, histopathological and Immunohistochemical assessments. In the early assessment (12th week post-infection) of infected-treated groups, the mean granuloma number showed significant reduction in groups treated with PZQ + PRP (IH) 10th week, PRP (IP), PZQ + PRP (IP) and PZQ + PRP (IH) 6th week (33.33%, 33%, 27.77% and 27.22%, respectively). Furthermore, the mean granuloma diameter showed significant reduction in groups treated with PRP (IH) 10th week and PZQ + PRP (IP) (24.17% and 15.5%, respectively). Also, the fibrotic index showed significant reduction in groups treated with PZQ + PRP (IP), PRP (IP) and PZQ + PRP (IH) 6th week (48.18%, 46.81% and 41.36%, respectively). Transforming growth factor ß1(TGF-ß1) expression was in correlation with parasitological and histopathological results. Diminished TGF-ß1 expression was mostly in infected groups treated with PZQ + PRP (IP), PZQ + PRP (IH) 6th week and PRP (IP) (88.63%, 88.63% and 77.27%, respectively). In the late assessment (14th week post-infection) of infected treated groups, TGF-ß1expression was reduced in groups treated with PZQ, PRP (IH) 10th weeks, PRP (IP) (83.33%, 66.66%, 33.33% respectively). PRP showed promising anti-fibrotic effects on S. mansoni-induced liver fibrosis.

4.
Dermatol Ther ; 35(11): e15811, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36086943

RESUMO

Isotretinoin is among the most frequently used medications in the dermatologic daily practice. With a Black box warning, teratogenicity is a major concern. Female fertility may be an issue to be investigated when it comes to its use in females. The aim of this work was to assess the effect of low dose isotretinoin on the ovarian reserve in female patients with moderate to severe acne. Sixty-sex female acne patients candidate for isotretinoin therapy and 66 controls were enrolled in this prospective controlled cohort study. Low dose isotretinoin (0.25-0.4 mg/kg/day) was given to the patients group for 6 months. Serum anti-Mullarian hormone (AMH), ovarian volume (OV) and Antral follicle count (AFC) were evaluated at baseline and 6 months after the last dose in the patients' group, and 1 year after the baseline assessment for the control subjects. There was no significant difference in serum AMH between patients after isotretinoin treatment and control subjects (p = 0.898). AMH failed to show any significant change in pre- and post- treatment levels in patients' group (p = 0.747). Both OV and AFC showed no significant changes in patient group when comparing pre- post- treatment levels on both sides (p > 0.05) and in control group between baseline and 1-year-interval levels on both sides (p > 0.05). Low-dose isotretinoin in treatment of moderate to severe acne seems to be safer on ovarian reserve as indicated by non-significant change in AMH levels as a sensitive parameter of female fertility.


Assuntos
Acne Vulgar , Reserva Ovariana , Humanos , Feminino , Isotretinoína/uso terapêutico , Hormônio Antimülleriano/farmacologia , Hormônio Antimülleriano/uso terapêutico , Estudos Prospectivos , Estudos de Coortes
5.
Medicine (Baltimore) ; 101(33): e29860, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35984137

RESUMO

Long-term glucocorticoids administration inhibits bone mineralization and has a negative impact on basic cellular mechanisms that are critical in the development and maintenance of bone strength. Steroids can cause osteoporosis in children and have a negative impact on bone mineral content (BMC) and bone mineral density (BMD). We aim to determine the BMD of children with idiopathic nephrotic syndrome (INS) who are on corticosteroids therapy. This cross-sectional study included 90 patients on corticosteroids therapy and 50 apparently healthy age and sex-matched children served as a control group. Renal functions, bone biochemistry, and parathyroid hormone (PTH) were measured in patients and controls. BMD was measured at the lumbar spinal region (L2-L4) using Dual-energy X-ray absorptiometry (DEXA) scan in both patients and controls groups. Serum PTH, phosphorous, and alkaline phosphatase levels were significantly higher in patients than in controls. There was a statistically significant reduction in blood calcium levels in patients compared to controls. Osteopenia was diagnosed by DEXA scan in 24 patients (26.7%) and osteoporosis in 12 patients (13.3 %). There was a statistically significant decline in BMD-z score, BMD, and BMC in patients compared to the healthy group. Patients with INS on corticosteroids treatment have a lower BMD than their peers. Pediatric INS patients had a high prevalence of osteopenia and osteoporosis as measured by DEXA. Steroid therapy has a deleterious impact on bone mineralization in children with INS.


Assuntos
Doenças Ósseas Metabólicas , Nefrose Lipoide , Síndrome Nefrótica , Osteoporose , Absorciometria de Fóton , Densidade Óssea , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/epidemiologia , Criança , Estudos Transversais , Densitometria , Humanos , Nefrose Lipoide/complicações , Síndrome Nefrótica/complicações , Síndrome Nefrótica/tratamento farmacológico , Osteoporose/induzido quimicamente , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Hormônio Paratireóideo , Esteroides
6.
Front Oncol ; 12: 877147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707368

RESUMO

Colorectal cancer (CRC) represents around 10% of all cancers, with an increasing incidence in the younger age group. The gut is considered a unique organ with its distinctive neuronal supply. The neuropeptide, human galanin, is widely distributed in the colon and expressed in many cancers, including the CRC. The current study aimed to explore the role of galanin at different stages of CRC. Eighty-one CRC cases (TNM stages I - IV) were recruited, and formalin-fixed paraffin-embedded samples were analyzed for the expression of galanin and galanin receptor 1 (GALR1) by immunohistochemistry (IHC). Galanin intensity was significantly lower in stage IV (n= 6) in comparison to other stages (p= 0.037 using the Mann-Whitney U test). Whole transcriptomics analysis using NGS was performed for selected samples based on the galanin expression by IHC [early (n=5) with high galanin expression and late (n=6) with low galanin expression]. Five differentially regulated pathways (using Absolute GSEA) were identified as drivers for tumor progression and associated with higher galanin expression, namely, cell cycle, cell division, autophagy, transcriptional regulation of TP53, and immune system process. The top shared genes among the upregulated pathways are AURKA, BIRC5, CCNA1, CCNA2, CDC25C, CDK2, CDK6, EREG, LIG3, PIN1, TGFB1, TPX2. The results were validated using real-time PCR carried out on four cell lines [two primaries (HCT116 and HT29) and two metastatic (LoVo and SK-Co-1)]. The current study shows galanin as a potential negative biomarker. Galanin downregulation is correlated with advanced CRC staging and linked to cell cycle and division, autophagy, transcriptional regulation of TP53 and immune system response.

7.
Medicine (Baltimore) ; 101(6): e28689, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35147090

RESUMO

ABSTRACT: A big problem is the delayed growth and sexual maturity in children with chronic kidney disease (CKD) with the consequent reduction in adults' height. Testosterone and estradiol have significant physiologic changes in children suffering from CKD, resulting in delayed puberty. We aim to assess blood levels of these hormones in patients with CKD-5 on regular hemodialysis.One hundred-six participants were enrolled in the current study, 56 of whom had CKD on hemodialysis 3 times a week 4 hours per session, and 60 healthy age- and gender-matched children acted as controls. Full history was taken, and a clinical review was performed on both patients and controls. The pubertal assessment was performed according to Tanner's classification and laboratory investigations of total and free serum (s.) testosterone in boys and s.estradiol in girls.Patients' weight and height were considerably lower than controls. The free and total s.testosterone of patients were significantly reduced. The same applies to s.estradiol levels which were substantially reduced in comparison to controls. In both patients and controls, Tanner staging & male total s.testosterone levels and female s.estradiol levels had significant positive associations. There was a negative association between the sex hormones levels and the disease's and dialysis duration in the patients' group.S.testosterone and s.estradiol levels were significantly low in CKD patients on dialysis and were positively correlated with delayed pubertal growth observed in those patients.


Assuntos
Estradiol/sangue , Puberdade/sangue , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/terapia , Testosterona/sangue , Adulto , Peso Corporal , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino
8.
Environ Sci Pollut Res Int ; 29(16): 23975-23987, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34820756

RESUMO

Wound healing is one of the utmost medical issues in human and veterinary medicine, which explains the urgent need for developing new agents that possess wound healing activities. The present study aimed to assess the effectiveness of green and chemical zinc oxide nanoparticles (ZnO-NPs) for wound healing. ZnO-NPs (green using Lawsonia inermis leaf extract and chemical) were synthesized and characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and high-resolution transmission electron microscopy (HRTEM). The gels containing the nanomaterials were prepared and inspected. Forty-five albino rats were divided into three groups, the control group was treated with normal saline 0.9%, and the other two groups were treated with gels containing green or chemical ZnO-NPs, respectively. On the 3rd, 7th, 14th, and 21st days post-treatment (PT), the wounds were clinicopathologically examined. Both nanomaterials have good crystallinity and high purity, but green ZnO-NPs have a longer nanowire length and diameter than chemical ZnO-NPs. The formed gels were highly viscous with a pH of 6.5 to 7. The treated groups with ZnO-NP gels showed clinical improvement, as decreased wound surface area (WSA) percent (WSA%), increased wound contraction percent (WC%), and reduced healing time (p < 0.05) when compared with the control group. The histological scoring showed that the epithelialization score was significantly higher at the 21st day post-treatment in the treated groups than in the control group (p < 0.05), but the vasculature, necrosis, connective tissue formation, and collagen synthesis scores were mostly similar. The green and chemical ZnO-NP gels showed promising wound healing properties; however, the L. inermis-mediated ZnO-NPs were more effective.


Assuntos
Lawsonia (Planta) , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Animais , Antibacterianos/química , Humanos , Lawsonia (Planta)/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Cicatrização , Difração de Raios X , Óxido de Zinco/química
9.
Medicine (Baltimore) ; 100(29): e26661, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34398026

RESUMO

ABSTRACT: Vitamin D deficiency is a worldwide public health problem. Low vitamin D and its consequences among children and adolescents could be considered as one of the most important health-related problems. This study aimed to estimate the prevalence of vitamin D deficiency in healthy Egyptian adolescents and investigate factors associated with vitamin D status.A cross-sectional study was conducted on 572 school children (270 males and 302 females) aged 14 to 18 years, who were randomly selected from high schools in one governorate in Egypt. Data were collected through a self-administered questionnaire. Vitamin D level, serum calcium, phosphorus, alkaline phosphates were measured.Vitamin D deficiency was almost present in all the studied Egyptian healthy adolescents (99%), 94.8% had vitamin D deficiency and 4.2% had vitamin D insufficiency. Girls had a higher prevalence of vitamin D deficiency than boys. There was a significant association between lack of physical activity, sun exposure, and vitamin D deficiency.Vitamin D deficiency and insufficiency are highly prevalent. In sunny countries, the special pattern of conservative clothing and the lack of outdoor physical activity might be the underlying factors for the high prevalence in females. Vitamin D supplementation seems to be mandatory to halt the problem.


Assuntos
Deficiência de Vitamina D/epidemiologia , Adolescente , Serviços de Saúde do Adolescente , Estudos Transversais , Egito/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Estudantes , Inquéritos e Questionários , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etiologia
10.
EXCLI J ; 16: 770-779, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28827993

RESUMO

The goal of the present study is to design a good anaesthetic program for dogs which can lead to optimal anaesthesia with no or minimal post-operative adverse effects. For this purpose, we designed two anaesthetic combinations and compared their effects in Mongrel dogs: combination 'A' consisting of atropine, xylazine, ketamine plus propofol, and combination 'B' consisting of atropine, diazepam, ketamine plus propofol. The onset and duration of anaesthesia induction, the duration of maintenance as well as the period of recovery were recorded and compared for both combinations. Furthermore, heart rate, respiratory rate, body temperature as well as blood picture were analyzed before and after administration of the proposed anaesthetic regimens. Administration of combination 'A' lead to rapid onset, within seconds, and induction of anaesthesia. The anaesthetic effect was maintained for approximately 29 minutes after injection of propofol. This was followed by very smooth recovery within approximately 68 minutes after induction of anaesthesia. In contrast, a less efficient induction and maintenance of anaesthesia as well as individual variability was observed after administration of combination 'B'. Approximately 14 minutes were needed for anaesthesia induction, which was maintained for 23 minutes after injection of propofol. Furthermore, administration of combination 'B' was associated with alterations in heart rate, body temperature and hematological picture. In conclusion, our results revealed that combined administration of atropine, xylazine, ketamine plus propofol (combination 'A') is considered satisfactory for anaesthesia in dogs with minimal post-operative side effects.

11.
Open Access Maced J Med Sci ; 4(4): 543-547, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28028388

RESUMO

BACKGROUND: Growing evidence supports the notion that the onset of tumorigenesis could occur through cancer stem cells (CSCs). These tumour cells show low proliferative rates, high self-renewal capacity, propensity to differentiate into active proliferating tumour cells & resistance to chemoradiotherapy thus, possibly causing local recurrences & metastasis formation. CD44 has been used as a marker to isolate CSCs from colorectal carcinoma (CRC). AIM: To investigate the immunohistochemical expression of cancer stem cells marker (CD44) in CRC and correlate its expression with the clinicopathological aspects, TNM staging and modified Dukes' classification. MATERIALS AND METHODS: Tumour biopsies from colectomy specimens of 60 patients with CRC were stained with hematoxylin-eosin for histological evaluation then immunostained with monoclonal antibodies against CD44 which was detected in term of negative or positive expression. RESULTS: CD44 was demonstrated in 58.3% (35/60) of cases and showed statistically significant correlation with tumour site and histological type (p-value < 0.05). However, CD44 showed statistically insignificant inverse correlation with tumour invasiveness (T), lymph node status (N), grade, TNM stage grouping and modified Dukes' classification, while it was directly correlated with distant metastasis (M) (p-value > 0.05). Chi-square /Fisher exact test proportion independence and the p-value are set significant at 0.05 level. CONCLUSION: the CD44 rate of expression is higher in the colon than rectum and in adenocarcinoma than mucinous and undifferentiated carcinoma. CD44 showed statistically insignificant relation with T, N, M, grade, TNM stage grouping and modified Dukes' classification.

12.
Arch Virol ; 161(8): 2095-102, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27155943

RESUMO

Human bocavirus (HBoV) is a prevalent virus worldwide and is mainly associated with respiratory disorders. Recently, it was detected in several disease conditions, including cancers. Colorectal cancer (CRC) is the third main cause of cancers worldwide. Risk factors that initiate cell transformation include nutritional, hereditary and infectious causes. The aim of the current study was to screen for the presence of HBoV in solid tumors of colorectal cancer and to determine the genotypes of the detected strains. Surgically excised and paraffin-embedded colorectal cancer tissue specimens from 101 male and female patients with and without metastasis were collected over the last four years. Pathological analysis and tumor stages were determined. The presence of HBoV was screened by polymerase chain reaction, and the genotype of the detected HBoV was determined by direct gene sequencing. Most of the examined specimens were adenocarcinoma with mucinous activity in many of them. Twenty-four out of 101 (23.8 %) CRC tissue specimens were found to contain HBoV-1. Low sequence diversity was recorded in the detected strains. The virus was detected in both male and female patients with an age range of 30-75 years. It is proposed that HBoV-1 could play a potential role in the induction of CRC.


Assuntos
Neoplasias Colorretais/virologia , Bocavirus Humano/isolamento & purificação , Infecções por Parvoviridae/virologia , Adulto , Idoso , Colo/patologia , Colo/cirurgia , Colo/virologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Bocavirus Humano/classificação , Bocavirus Humano/genética , Bocavirus Humano/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Parvoviridae/patologia , Infecções por Parvoviridae/cirurgia , Filogenia
13.
Acta Crystallogr D Biol Crystallogr ; 67(Pt 7): 646-56, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21697603

RESUMO

X-ray transparent crystallization plates based upon a novel drop-pinning technology provide a flexible, simple and inexpensive approach to protein crystallization and screening. The plates consist of open cells sealed top and bottom by thin optically, UV and X-ray transparent films. The plates do not need wells or depressions to contain liquids. Instead, protein drops and reservoir solution are held in place by rings with micrometre dimensions that are patterned onto the bottom film. These rings strongly pin the liquid contact lines, thereby improving drop shape and position uniformity, and thus crystallization reproducibility, and simplifying automated image analysis of drop contents. The same rings effectively pin solutions containing salts, proteins, cryoprotectants, oils, alcohols and detergents. Strong pinning by rings allows the plates to be rotated without liquid mixing to 90° for X-ray data collection or to be inverted for hanging-drop crystallization. The plates have the standard SBS format and are compatible with standard liquid-handling robots.


Assuntos
Cristalografia por Raios X/instrumentação , Proteínas/análise , Automação Laboratorial/instrumentação , Automação Laboratorial/métodos , Cristalização , Cristalografia por Raios X/métodos
14.
J Air Waste Manag Assoc ; 58(5): 641-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18512441

RESUMO

The Traffic Air Quality (TAQ) model is a simple tool to estimate traffic fine particulate emissions on roadways (g/km) and can be used for both real-time analysis and for localized conformity analysis ("hot-spot" analysis for nonattainment areas) as defined by 40 CFR 93.123. This paper is a follow-up to a study published earlier regarding the development of the TAQ model. This paper shows how local air quality levels can be a factor in traffic management in nonattainment areas. Similar to the industrial source quotas measured in tons per year, it is proposed that road segments are to be assigned emission quotas (or TAQ indices) measured in pollutant mass emitted per road length (g/km) above which traffic-measures have to be taken to reduce the fine-particulates emissions on such road links. The TAQ model as well as traffic-rerouting measures along with the Intelligent Transportation System (ITS) protocols can be used to have a real-time control of the traffic conditions along expressways to maintain the fine-particulates emissions below the quota assigned per road link and consequently improving the over all local air quality in nonattainment areas.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Automóveis , Modelos Estatísticos
15.
J Air Waste Manag Assoc ; 56(11): 1540-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17117739

RESUMO

The purpose of the study was to quantify the impact of traffic conditions, such as free flow and congestion, on local air quality. The Borman Expressway (I-80/94) in Northwest Indiana is considered a test bed for this research because of the high volume of class 9 truck traffic traveling on it, as well as the existing and continuing installation of the Intelligent Transportation System (ITS) to improve traffic management along the highway stretch. An empirical traffic air quality (TAQ) model was developed to estimate the fine particulate matter (PM2.5) emission factors (grams per kilometer) based solely on the measured traffic parameters, namely, average speed, average acceleration, and class 9 truck density. The TAQ model has shown better predictions that matched the measured emission factor values more than the U.S. Environmental Protection Agency (EPA)-PART5 model. During congestion (defined as flow-speeds < 50 km/hr [30 mi/hr]), the TAQ model, on average, overpredicted the measured values only by a factor of 1.2, in comparison to a fourfold underprediction using the EPA-PART5 model. On the other hand, during free flow (defined as flow-speeds > 80 km/hr [50 mi/hr]), the TAQ model was conservative in that it overpredicted the measured values by 1.5-fold.


Assuntos
Poluentes Atmosféricos/análise , Modelos Teóricos , Material Particulado/análise , Emissões de Veículos/análise , Exposição Ambiental , Monitoramento Ambiental , Indiana , Tamanho da Partícula , Vento
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