Laurentiu Vasile Sima

Prof. Dr. Laurentiu Vasile Sima

Surgycal semiology, University of Medicine and Pharmacy Victor Babes, Timişoara, Timiş, Romania
orcid
Dr

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
25 September 2023 in Microorganisms
Verified
Journal Article
Open access
PDF file
A(Ana Alexandra Ardelean (Paduraru)
Ana Alexandra Ardelean (Paduraru)
MLMaria Alina Lupu
Maria Alina Lupu
Laurentiu Vasile SimaLaurentiu Vasile Sima
Laurentiu Vasile Sima
GCGabriel Veniamin Cozma
Gabriel Veniamin Cozma
SOSorin Olariu
Sorin Olariu
Tudor Rares OlariuTudor Rares Olariu
Tudor Rares Olariu
Cystic echinococcosis (CE) is a neglected parasitic disease caused by the tapeworm Echinococcus granulosus. The aim of this study was to assess the epidemiological features of human cystic echinococcosis in patients from Western Romania. We retrospectively investigated the medical records of patients hospitalized with CE between 1 January 2007 and 1 September 2022. A total of 366 patients (range 18–90 years) were recorded. The number of hospitalized individuals was higher in patients aged 50–59 years (83/366, 22.7%), in females (194/366, 53%), and in residents of rural areas (225/366, 61.5%). The liver was the most common localization of the cysts (302/366, 82.5%). Ninety-eight patients (26.8%) presented complications, including biliary fistula, allergies, and infection of the cyst. Patients with complications had a longer mean hospital stay (15.7 ± 8.3 days) compared to patients without complications (11.5 ± 7.3 days) (p < 0.001). The results of this study revealed that patients diagnosed with CE required hospitalization and extended medical care, indicating that this zoonotic disease remains a significant public health problem in Western Romania. Public health authorities should enhance CE surveillance by implementing control programs and mandatory notification of new cases.

12 August 2025 in Antioxidants
Verified
Journal Article
Open access
PDF file
SRSonia Ratiu
Sonia Ratiu
MIMARIȘ MIHAELA IOANA
MARIȘ MIHAELA IOANA
AFAdina V. Furdui-Lința
Adina V. Furdui-Lința
Laurentiu Vasile SimaLaurentiu Vasile Sima
Laurentiu Vasile Sima
TBTiberiu Bratu
Tiberiu Bratu
OCOctavian Marius Cretu
Octavian Marius Cretu
Chronic venous disease (CVD) and its major manifestation, varicose veins (VV) of the lower limbs, is a common, multifactorial disease that affects a significant percentage of adult and elderly people worldwide. Its prevalence has been constantly increasing with the aging of the population and, particularly, with the obesity pandemic (hence, the term ‘phlebesity’). The major pathophysiological mechanisms that are potentiating each other in a vicious cycle, leading to chronic venous hypertension, are represented by endothelial dysfunction, chronic inflammation, impaired hemodynamics, and venous wall remodeling. Oxidative stress is another pathomechanism responsible for CVD and its complications, with the increased generation of reactive oxygen species and decreased antioxidant defense being reported to contribute to VV formation. Herein, we present evidence for the role of impaired redox homeostasis as pathophysiological mechanism responsible for chronic local and systemic oxidative stress in patients with CVD.

11 January 2025 in Biomedicines
Verified
Journal Article
Open access
PDF file
LGLaura Andreea Ghenciu
Laura Andreea Ghenciu
MGMirela Grigoras
Mirela Grigoras
MRMaria Luminioara Rosu
Maria Luminioara Rosu
SBSorin Lucian Lucian Bolintineanu
Sorin Lucian Lucian Bolintineanu
Laurentiu Vasile SimaLaurentiu Vasile Sima
Laurentiu Vasile Sima
OCOctavian Marius Cretu
Octavian Marius Cretu
Background and Objectives: This study aimed to identify and analyze imaging and pathological features that differentiate liver metastases from primary liver cancer in patients with histopathological confirmation, and to evaluate the diagnostic accuracy of imaging modalities. Materials and Methods: This retrospective study included 137 patients who underwent liver biopsy or resection between 2016 and 2024, comprising 126 patients with liver metastases and 11 patients with primary liver cancer (hepatocellular carcinoma). Imaging features on contrast-enhanced MRI were evaluated, including lesion number, size, margins, enhancement patterns, presence of capsule, T1/T2 signal characteristics, diffusion-weighted imaging (DWI) signal, and portal vein thrombosis. Laboratory data such as liver function tests and alpha-fetoprotein (AFP) levels were collected. Pathological features recorded included tumor differentiation, vascular invasion, necrosis, and fibrosis. Statistical analyses were performed using chi-squared tests, t-tests, and logistic regression, with a significance level of p < 0.05. The diagnostic accuracy of imaging features was assessed using receiver operating characteristic (ROC) curve analysis. Results: Liver metastases were more likely to present as multiple lesions (82.5% vs. 27.3%, p < 0.001), had irregular margins (78.6% vs. 36.4%, p = 0.002), rim enhancement (74.6% vs. 18.2%, p < 0.001), and were hypointense on T1-weighted images (85.7% vs. 45.5%, p = 0.004). Primary liver cancers were more likely to be solitary (72.7% vs. 17.5%, p < 0.001), have smooth margins (63.6% vs. 21.4%, p = 0.002), exhibit arterial phase hyperenhancement (81.8% vs. 23.8%, p < 0.001), and portal venous washout (72.7% vs. 19.0%, p < 0.001). Vascular invasion was more common in primary liver cancer (45.5% vs. 11.1%, p = 0.01). AFP levels > 400 ng/mL were significantly associated with primary liver cancer (63.6% vs. 4.8%, p < 0.001). ROC curve analysis showed that a combination of imaging features had an area under the curve (AUC) of 0.91 for differentiating the two entities. Conclusions: Imaging features such as lesion number, margin characteristics, enhancement patterns, T1/T2 signal characteristics, and portal venous washout, along with pathological features like vascular invasion and AFP levels, can effectively differentiate liver metastases from primary liver cancer. The diagnostic accuracy of imaging is high when multiple features are combined.

19 June 2024 in Medicina
Verified
Journal Article
Open access
PDF file
DPDorel Popovici
Dorel Popovici
CSCristian Stanisav
Cristian Stanisav
Laurentiu Vasile SimaLaurentiu Vasile Sima
Laurentiu Vasile Sima
Alina NegruAlina Negru
Alina Negru
SMSERGIU MURG
SERGIU MURG
ACAdrian Carabineanu
Adrian Carabineanu
Background and objectives: Colorectal cancer is a major global health concern, with a significant increase in morbidity and mortality rates associated with metastatic stages. This study investigates the prognostic significance of various clinical and laboratory parameters in patients with metastatic CRC. Materials and Methods: A retrospective cohort of 188 CRC patients with hepatic metastasis from the OncoHelp Association in Timisoara was analyzed from January 2016 to March 2023. Data on demographics, clinical characteristics, and biomarkers, such as lymphocyte counts, as well as various inflammation indices, were examined. Statistical analyses included univariate and multivariate logistic regression, Kaplan-Meier survival analysis, and ROC curve assessments. Results: Our findings indicate significant associations between survival outcomes and several biomarkers. Higher BMI and lymphocyte counts were linked with better survival rates, while higher values of Neutrophil-Hemoglobin-Lymphocyte (NHL) score, Neutrophil-Lymphocyte Ratio (NLR), Platelet-Lymphocyte Ratio (PLR), and Systemic Immune-Inflammation Index (SII) were predictors of poorer outcomes. Notably, the presence of hepatic metastasis at diagnosis was a critical factor, significantly reducing overall survival. Conclusions: The study has expanded the current understanding of prognostic factors in CRC, advocating for a multi-dimensional approach to prognostic evaluations. This approach should consider not only the traditional metrics such as tumor stage and histological grading but also incorporate a broader spectrum of biomarkers. Future studies should aim to validate these findings and explore the integration of these biomarkers into routine clinical practice, enhancing the precision of prognostic assessments and ultimately guiding more personalized treatment strategies for CRC patients.

16 August 2024 in Cancers
Verified
Journal Article
Open access
PDF file
TCTrandafir Cornelia
Trandafir Cornelia
RCRaluca Maria Cloșca
Raluca Maria Cloșca
MMMarioara Mot
Marioara Mot
OSOana Silvana Sarau
Oana Silvana Sarau
CSCristian Andrei Sarau
Cristian Andrei Sarau
Laurentiu Vasile SimaLaurentiu Vasile Sima
Laurentiu Vasile Sima
Sinonasal mucosal melanoma originates from melanocytes and it is a rare malignancy in the sinonasal tract. It is an aggressive melanocytic neoplasm with a very poor prognosis. The symptoms are nonspecific and the diagnosis is delayed, usually until the advanced stages of the disease. The current study performs a correlation between the histopathological aspects of sinonasal mucosal melanoma and different types of immune cells present in the microenvironment, with prognostic and therapeutic implications. The endpoint is to quantify the cellular immune microenvironment and correlate it with patient survival. This study presents nine cases of primary sinonasal mucosal melanomas diagnosed at the Emergency City Hospital Timisoara, Romania during a period of 15 years. The histopathological examination was performed in the Department of Pathology of the same hospital, using morphological hematoxylin–eosin staining. Additional immunohistochemical reactions were performed to confirm the diagnosis and evaluate the components of the tumor immune microenvironment. This study identifies eosinophils, macrophages, natural killer cells and plasma cells as favorable prognostic factors. Therefore, a CD8:CD4 ratio of more than 3 is correlated with a good response to PD-1 inhibitor therapy.

7 November 2019 in Medicina
Verified
Journal Article
Open access
PDF file
AVAnda Cornelia Vizitiu
Anda Cornelia Vizitiu
DSDanae Stambouli
Danae Stambouli
APAnca Gabriela Pavel
Anca Gabriela Pavel
MMMaria-Cezara Muresan
Maria-Cezara Muresan
DADiana Maria Anastasiu
Diana Maria Anastasiu
Laurentiu Vasile SimaLaurentiu Vasile Sima
Laurentiu Vasile Sima
Background and Objective: Although Down syndrome is the most frequent aneuploidy, its pathogenic molecular mechanisms are not yet fully understood. The aim of our study is to quantify—by qRT-PCR—the expression levels of both the mature forms and the pri-miRNAs of the microRNAs resident on chromosome 21 (miR(21)) in the amniotic fluid samples from Down syndrome singleton pregnancies and to estimate the impact of the differentially expressed microRNAs on Down syndrome fetal heart and amniocytes transcriptomes. Materials and methods: We collected amniotic fluid samples harvested by trained obstetricians as part of the second trimester screening/diagnostic procedure for aneuploidies to assess the trisomy 21 status by QF-PCR and karyotyping. Next, we evaluated—by Taqman qRT-PCR—the expression levels of both the mature forms and the pri-miRNA precursors of the microRNAs resident on chromosome 21 in amniotic fluid samples from singleton Down syndrome and euploid pregnancies. Further, we combined miRWalk 3.0 microRNA target prediction with GEO DataSets analysis to estimate the impact of hsa-miR-99a abnormal expression on Down syndrome heart and amniocytes transcriptome. Results: We found a statistically significant up-regulation of the mature form of miR-99a, but not pri-miR-99a, in the amniotic fluid samples from Down syndrome pregnancies with female fetuses. GATHER functional enrichment analysis of miRWalk3.0-predicted targets from Down syndrome amniocytes and fetal hearts transcriptome GEODataSets outlined both focal adhesion and cytokine–cytokine receptor interaction signaling as novel signaling pathways impacted by miR-99a and associated with cardiac defects in female Down syndrome patients. Conclusions: The significant overexpression of miR-99a, but not pri-miR-99a, points towards an alteration of the post-transcriptional mechanisms of hsa-miR-99a maturation and/or stability in the female trisomic milieu, with a potential impact on signaling pathways important for proper development of the heart.