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1.
Traffic Inj Prev ; : 1-11, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39325682

RESUMEN

OBJECTIVE: Loop ramps are complex due to their combination of horizontal curves and vertical alignments. Analyzing driving behavior and measuring safety levels can provide insights for designers, helping to improve the performance and alignment of design assumptions with actual driving behavior on loops. Therefore, the primary objective of this research is to explore the safety, performance and geometric configuration of the main body and general shape of free-flow loop ramps in the free-following mode. METHODS: The study uses data from a UAV to investigate vehicle demand behavior. Maximum lateral acceleration (ay,i) in loops is used as a Surrogate Safety Measure (SSM), along with a new parameter, the a/b ratio, to determine the general shape of loop bodies. The study presents the Loop Safety Level (LSL), an approach for proactive risk analysis and ranking that relies on threshold lateral acceleration (at), 85th percentile maximum lateral acceleration (ay,max,85%), and crash analysis. RESULTS: A higher LSL value points to a more critical safety concern regarding the loop's shape in relation to lateral acceleration caused by driving behaviors. Comparing crash statistics with lateral acceleration results enables the LSL to provide appropriate safety ratings and diagnose loop segment safety. A prediction model for maximum lateral acceleration, based on loop geometry, demonstrates a good fit (R2=0.88) between observed and predicted data. CONCLUSIONS: The study enhances understanding of safety considerations in geometric configuration and general shape enhancement of loops during the design process.

2.
Artículo en Inglés | MEDLINE | ID: mdl-32824601

RESUMEN

Road transportation poses one of the significant public health risks. Several contributors and factors strongly link public health and road safety. The design and advancement of higher-quality roads can significantly contribute to safer roads and save lives. In this article, the safety aspect of the roads' horizontal curves under the standard of the American Association of State Highway Transportation Officials (AASHTO) is evaluated. Several factors, including vehicle weight, vehicle dimensions, longitudinal grades, and vehicle speed in the geometric design of the horizontal curves, are investigated through a multi-body dynamic simulation process. According to the AASHTO, a combination of simple circular and clothoid transition curves with various longitudinal upgrades and downgrades was designed. Three vehicles were used in this simulation, including a sedan, a bus, and a 3-axle truck. The analysis was based on the lateral friction between the tire and the pavement and also the safety margin parameter. The results showed that designers must differentiate between light and heavy vehicles, especially in curves with a high radius. Evaluation of longitudinal grade impacts indicated that the safety margin decreases when the vehicle is entering the curve. Safety margin reduction on the clothoid curve takes place with a lower grade toward the simple circular curve. By increasing the speed, the difference between lateral friction demand obtained from simulation and lateral friction demand proposed by AASHTO grows. The proposed novel methodology can be used for evaluating road safety.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Planificación Ambiental , Accidentes de Tránsito/prevención & control , Fricción , Vehículos a Motor , Seguridad
7.
IUBMB Life ; 68(8): 629-33, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27273823

RESUMEN

Renal cell carcinoma (RCC) represents, on average, over 90% of all malignancies of the kidney that occur in adults in both sexes. Chemokine receptors expression has been found in many kinds of cancer and at tumor metastasis site. We determined CXCR2 and CXCR3 expression in RCC by immunohistochemistry method and analyzed the prognostic value of these markers. Our finding demonstrated that CXCR3 were highly overexpressed in renal cancer tissues compared with those adjacent normal kidney tissues (P < 0.001). The results showed that high expression of CXCR3 was markedly correlated with metastasis (P = 0.021) and tumor stage (P = 0.031). CXCR2 were overexpressed in renal cancer tissues compared with those adjacent normal kidney tissues (P < 0.001). Our result showed that CXCR2 expression was correlated with high grade (P = 0.024), advanced stage (P = 0.029) and metastasis (P = 0.018). The log-rank test revealed that high CXCR2 and CXCR3 expressions are related to poorer overall survival (P < 0.001; P < 0.001). In conclusion, this study indicates the correlation of CXCR3 and CXCR3 with progression of RCC. In addition, high CXCR3 andCXCR2 expressions were correlated with shorter overall survival. © 2016 IUBMB Life, 68(8):629-633, 2016.


Asunto(s)
Carcinogénesis/genética , Carcinoma de Células Renales/genética , Receptores CXCR3/genética , Receptores de Interleucina-8B/genética , Adulto , Anciano , Carcinoma de Células Renales/patología , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Receptores CXCR3/biosíntesis , Receptores de Interleucina-8B/biosíntesis
8.
Tumour Biol ; 37(6): 8153-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26715275

RESUMEN

Current evidences have indicated that osteosarcoma is strongly associated with abnormal genetic and epigenetic changes that lead to the abnormal expression of oncogenes or methylation of tumor suppressor genes. In the present study, MACC1 and CDC5L mRNA levels in the patients with osteosarcoma were evaluated using quantitative real-time PCR. Our results demonstrated that CDC5L mRNA levels were higher in tumor tissues than in adjacent normal tissues (2.713 ± 0.738 vs. 1.071 ± 0.629; P < 0.05). Moreover, MACC1 was upregulated in tumor bone tissues than in adjacent normal tissues (3.221 ± 0. 624 vs. 1.427 ± 0.456; P < 0.05). Our result demonstrated that high expression of CDC5L was significantly related to advanced TNM stage (P = 0.032). No significant difference was determined between CDC5L mRNA expression and other clinicopathological parameters including age, gender, tumor diameter, location, tumor grade, and histological type. In addition, overexpression of MACC1 was strongly correlated with advanced TNM stage (P = 0.027) and high tumor grade (P = 0.035). Our findings indicated that mRNA level of CDC5L is correlated with advanced TNM stage, and MACC1 may be involved in progression of osteosarcoma.

9.
Tumour Biol ; 37(6): 7501-5, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26678893

RESUMEN

Current evidences indicated that a group of soluble mediators called chemokines is involved in tumor growth and metastasis. The association of IL-8 with tumor cell migration was previously found, and its expression was related to angiogenesis, tumor progression, and metastasis in many kinds of carcinomas in human and animal models. Furthermore, it has been showed that IL-17 plays its role as either a proteome of tumor progression or antitumor indifferent cancer models. To investigate the messenger RNA (mRNA) expressions of IL-8 and IL-17 in patients with colorectal cancer (CRC) and non-tumor tissue, quantitative real-time PCR was used in the study. Our results showed that expression of IL-8 mRNA was significantly increased in tumor tissues (mean ± SD 3.84 ± 0.08) compared with adjacent normal mucosa (mean ± SD 1.17 ± 0.75, P = 0.001). Furthermore, a higher expression of IL-17 mRNA was found in tumor tissues (mean ± SD 2.73 ± 0.69) when compared with normal tissues (mean ± SD 1.06 ± 0.07, P = 0.001). Our findings indicated that advanced tumor-node-metastasis (TNM) stage (P = 0.024) and histological grade (poorly differentiated, P = 0.013) and distant metastasis (P = 0.001) were correlated with expression of IL-8. Moreover, high expression of IL-17 showed significant association with early stage CRC (TNM) (P = 0.038). In conclusion, the expression of IL-8 and IL-17 mRNAs was significantly increased in tumor tissues compared with adjacent normal tissues. We found that advanced TNM stage and histological grade and distant metastasis were correlated with expression of IL-8, while high expression of IL-17 showed significant association with early stage CRC (TNM) stage and overexpression of IL-8 may be associated with progression of CRC.

10.
Tumour Biol ; 37(6): 7583-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26687644

RESUMEN

In order to evaluate the correlation of B7-H4 and B7-H1 with renal cell carcinoma (RCC), we analyzed B7-H1 and B7-H4 expressions and their clinical significance by immunohistochemical method. Our result indicated that B7-H4-positive staining was detected in 58.13 % of RCC tissues (25 tissues tumors), and there were 18 tissues of patients without detectable B7-H4. Furthermore, 21 cases (48.83 %) were B7-H1-positive. Positive tumor expressions of B7-H4 and B7-H1 were markedly related to advanced TNM stage (P = 0.001; P = 0.014), high grade (P = 0.001; P = 002), and larger tumor size (P = 0.002; P = 024) in RCC tissues than patients with B7-H4-negative and B7-H1-negative in RCC tissues. The patients with B7-H1 and B7-H4-positive expressions were found to be markedly correlated with the overall survival of the patients (P < 0.05) and tended to have an increased risk of death when compared with negative expression groups. Univariate analysis showed that B7-H4 and B7-H1 expressions, TNM stage, high grade, and tumor size were significantly related to the prognosis of RCC. Furthermore, multivariate analysis showed that B7-H4 and B7-H1 expressions decreased overall survival. The adjusted HR for B7-H1 was 2.83 (95 % CI 1.210-2.971; P = 0.031) and also was 2.918 (95 % CI 1.243-3.102; P = 0.006) for B7-H4 that showed these markers were independent prognostic factors in RCC patients. The expressions of B7-H1 and B7-H4 in RCC patients indicate that these markers may be as a predictor of tumor development and death risk. Further investigations can be helpful to confirm B7-H1 and B7-H4 roles as an independent predictor of clinical RCC outcome.

11.
Arch Gynecol Obstet ; 289(4): 845-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24121689

RESUMEN

PURPOSE: The aim of this study was to assess the frequency of different histopathological findings obtained from dilatation and curettage (D&C) specimens in patients with abnormal uterine bleeding (AUB). METHODS: In a retrospective review of 591 specimens, the included subjects were all women with AUB who underwent D&C between 2002 and 2006 in Be'sat Hospital, Tehran, Iran. The pathological diagnoses were analyzed in four groups from normal to malignant endometrium. The pathological groups were evaluated for patients' characteristics including demographic data and medical history. RESULTS: The majority of patients (61.6%) were in the 41-50 year age group. Totally, 81.4% of patients had normal pathology. The disordered proliferative endometrium/polyps, hyperplasia, and malignant pathology were found in 15.4, 2.5, and 0.7% of specimens, respectively. The abnormal pathologies were seen more among patients with postmenopausal status, nulli-/primigravid women, and those with hypertension, diabetes, hypothyroidism, and polycystic ovary syndrome. CONCLUSIONS: The proliferative endometrium and secretory endometrium were the most common histopathological observations in AUB patients in our region, and except normal endometrium, disordered proliferative endometrium was the most common cause of AUB.


Asunto(s)
Dilatación y Legrado Uterino/estadística & datos numéricos , Endometrio/patología , Pólipos/patología , Hemorragia Uterina/patología , Adulto , Biopsia , Dilatación y Legrado Uterino/efectos adversos , Femenino , Humanos , Irán , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Hemorragia Uterina/etiología
12.
Turk Patoloji Derg ; 29(1): 15-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23354791

RESUMEN

OBJECTIVE: To investigate the frequency of hemophagocytic syndrome in a series of patients with otherwise unexplained cytopenia. MATERIAL AND METHOD: In this cross-sectional, single-centre study, bone marrow specimens (n=288) were obtained from the patients with unexplained cytopenia. The diagnosis of hemophagocytic syndrome was made according to universally accepted criteria. Characteristics of the patients, as well as the clinical and laboratory findings were reported. RESULTS: Fifteen cases (5.2%) fulfilled the hemophagocytic syndrome criteria, including 8 males (53.3%) and 7 females (46.7%) with a mean age of 39.7±20.7 (range: 14-72) years at the time of diagnosis. The main clinical and laboratory findings were cytopenia (100%), fever (73.3%), hyperferritinemia (66.7%), elevated erythrocyte sedimentation rate (60%), hypertriglyceridemia (60%), organomegaly (53.3%), elevated liver enzymes (53.3%), lymphadenopathy (26.7%), neurological symptoms (20%), and skin rash (13.3%). Two patients (13.3%) died before a diagnosis was made. CONCLUSION: Our findings indicate that the hemophagocytic syndrome is not a rare pathologic condition in patients with otherwise unexplained cytopenia. Without treatment, the mortality rate may be high.


Asunto(s)
Linfohistiocitosis Hemofagocítica/complicaciones , Linfohistiocitosis Hemofagocítica/diagnóstico , Pancitopenia/etiología , Trombocitopenia/etiología , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Linfohistiocitosis Hemofagocítica/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
13.
World J Gastrointest Surg ; 3(10): 156-8, 2011 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-22110848

RESUMEN

Degos' disease, otherwise known as "malignant atrophic papulosis" is a rare vasculopathy with an unknown etiology characterized by typical cutaneous lesions. Involvement of the gastrointestinal (GI) tract is observed in approximately half of patients and small infarctions in the mucosa can cause perforation and resulting peritonitis, the leading cause of death. We present a fatal case of Degos' disease with skin and GI involvement, manifesting as recurrent intestinal perforations and peritonitis, in a 15-year-old Iranian boy.

14.
J Vasc Surg ; 36(6): 1264-6, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12469061

RESUMEN

Isolated intractable bleeding from anorectal varices is a rare complication of portal hypertension. We report a case of a patient with cirrhosis and hepatofugal flow who had severe lower gastrointestinal bleeding from anorectal varices. This is the first case report of construction of a distal inferior mesenteric vein shunt to left renal vein as a selective shunt for treatment of bleeding anorectal varices in a patient with hepatofugal flow. The patient is a 39-year-old white man with a medical history significant for alcohol abuse who was seen with bright red blood per rectum requiring 10 units of packed red blood cells over the course of a year. The work-up revealed anorectal varices with no other colonic lesions. The patient underwent construction of a distal inferior mesenteric vein to left renal vein shunt.


Asunto(s)
Anastomosis Quirúrgica , Hemorragia Gastrointestinal/complicaciones , Hemorragia Gastrointestinal/cirugía , Venas Mesentéricas/cirugía , Recto/irrigación sanguínea , Recto/cirugía , Venas Renales/cirugía , Várices/complicaciones , Várices/cirugía , Adulto , Hemorragia Gastrointestinal/diagnóstico por imagen , Humanos , Masculino , Venas Mesentéricas/diagnóstico por imagen , Radiografía , Recto/diagnóstico por imagen , Venas Renales/diagnóstico por imagen , Várices/diagnóstico por imagen
15.
Ann Vasc Surg ; 16(3): 358-62, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11957001

RESUMEN

Primary arterial dissection of the peripheral vessels is a rare condition. We report a case of spontaneous dissection of the distal superficial femoral artery compounded by distal embolization leading to ischemic symptoms. The patient was successfully treated with exploration of the superficial femoral artery over the area of the dissection, distal embolectomy, and reconstruction by way of an interposition graft. Awareness of this condition leads to potentially earlier diagnosis and expands the therapeutic options.


Asunto(s)
Disección Aórtica/complicaciones , Embolia/etiología , Arteria Femoral , Isquemia/etiología , Pierna/irrigación sanguínea , Humanos , Masculino , Persona de Mediana Edad
16.
Vasc Endovascular Surg ; 36(1): 51-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12704525

RESUMEN

Isolated left lower extremity swelling secondary to left iliac vein compression was first described by McMurrich in 1908, and defined anatomically by May and Thurner in 1957 and clinically by Cockett and Thomas in 1965. The left iliac vein is usually located posterior to the right iliac artery and can be compressed between the artery and the fifth lumbar vertebrae. Symptoms include left lower extremity edema, pain, varicosities, venous stasis changes, and deep venous thrombosis. Evaluation of these patients historically included a venous duplex scan to rule out deep venous thrombosis and an abdominal computed tomography scan to rule out pelvic mass. This paper describes the use of magnetic resonance imaging and venography in the evaluation of patients with isolated left lower extremity swelling. A retrospective analysis of a series of 24 patients who presented with symptomatic left lower extremity edema was performed. Infrainguinal deep venous thrombosis and valvular reflux was evaluated by duplex scan. The presence of suprainguinal deep venous thrombosis and pelvic mass was evaluated by magnetic resonance imaging. Magnetic resonance imaging was used to define the anatomic characteristics of the May-Thurner syndrome. Patients identified with the syndrome were treated either conservatively with lower extremity compression and elevation or with angioplasty and stenting. Follow-up of this subset of patients was performed with clinical assessment of the resolution of their symptomatic lower extremity edema as well as quality of life assessments via phone interviews. Twenty-four patients were evaluated for isolated left lower extremity swelling. Seven patients had positive results on duplex scans for deep venous thrombosis. Magnetic resonance imaging results demonstrated 1/24 (4%) had a pelvic mass compressing the iliac vein; 2/24 (8%) patients had iliac vein thrombosis; 1/24 (4%) patients with a history of deep venous thrombosis demonstrated a long stenotic segment of the left iliac vein unrelated to its association with the right iliac artery; 9/24 patients (37%) had anatomic evidence of May-Thurner syndrome; and 2/24 patients (8%) had isolated left lower extremity swelling of unknown etiology. Five patients diagnosed with May-Thurner syndrome were treated conservatively with compression stockings and leg elevation. Four patients with May-Thurner syndrome underwent iliac vein angioplasty and stenting. Technical success was 100%. On clinical follow-up, the patients with May-Thurner syndrome have had improvement/resolution of their symptoms. There have been no complications from either therapy. May-Thurner syndrome is a clinical entity of left iliac vein compression by the right iliac artery, resulting in isolated left lower extremity swelling and may be a precipitating factor for iliofemoral deep venous thrombosis. Magnetic resonance imaging is the best modality for diagnosis of this entity as it can rule out the presence of pelvic masses and deep venous thrombosis while simultaneously demonstrating the anatomy characteristic of this syndrome.


Asunto(s)
Vena Femoral/diagnóstico por imagen , Vena Femoral/patología , Vena Ilíaca/diagnóstico por imagen , Vena Ilíaca/patología , Imagen por Resonancia Magnética , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Enfermedades Vasculares Periféricas/patología , Flebografía , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/patología , Adolescente , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/terapia , Estudios Retrospectivos , Sensibilidad y Especificidad , Síndrome , Trombosis de la Vena/terapia
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