Catalin Vasilescu

MicroRNA fingerprints identify miR-150 as a plasma prognostic marker in patients with sepsis

BACKGROUND The physiopathology of sepsis continues to be poorly understood, and despite recent advances in its management, sepsis is still a life-threatening condition with a poor outcome. If new diagnostic markers related to sepsis pathogenesis will be identified, new specific therapies might be developed and mortality reduced. Small regulatory non-coding RNAs, microRNAs (miRNAs), were recently linked to various diseases; the aim of our prospective study was to identify miRNAs that can differentiate patients with early-stage sepsis from healthy controls and to determine if miRNA levels correlate with the severity assessed by the Sequential Organ Failure Assessment (SOFA) score. METHODOLOGY/PRINCIPAL FINDINGS By using genome-wide miRNA profiling by microarray in peripheral blood leukocytes, we found that miR-150, miR-182, miR-342-5p, and miR-486 expression profiles differentiated sepsis patients from healthy controls. We also proved by quantitative reverse transcription-polymerase chain reaction that miR-150 levels were significantly reduced in plasma samples of sepsis patients and correlated with the level of disease severity measured by the SOFA score, but were independent of the white blood counts (WBC). We found that plasma levels of tumor necrosis factor alpha, interleukin-10, and interleukin-18, all genes with sequence complementarity to miR-150, were negatively correlated with the plasma levels of this miRNA. Furthermore, we identified that the plasma levels ratio for miR-150/interleukin-18 can be used for assessing the severity of the sepsis. CONCLUSIONS/SIGNIFICANCE We propose that miR-150 levels in both leukocytes and plasma correlate with the aggressiveness of sepsis and can be used as a marker of early sepsis. Furthermore, we envision miR-150 restoration as a future therapeutic option in sepsis patients.

Laparoscopic subtotal splenectomy in hereditary spherocytosis

BackgroundClinical manifestations of hereditary spherocytosis can be controlled by splenectomy. The use of this procedure has been restricted due to concerns regarding exposure of patients to a lifelong risk of overwhelming infections. Subtotal splenectomy, which removes 85–90% of the enlarged spleen, is a logical alternative. In the first cases performed by laparoscopy we have chosen to preserve the upper pole. However, this technique showed some disadvantages, especially concerning the correct intraoperative evaluation of the splenic remnant volume. Therefore, we developed a new variant of the procedure by preserving the lower pole of the spleen.MethodsBased on the authors’ experience in laparoscopy (176 laparoscopic splenectomies), 10 laparoscopic subtotal splenectomies were performed in patients with hereditary microspherocytosis, preserving either the upper or the lower splenic pole.ResultsPatient age ranged between 5 and 35 years. The mean volume of the remnant spleen was 41.4 cm3. There were no complications, and no transfusions were needed. Follow-up for 1–30 months was available.ConclusionsSubtotal splenectomy appears to control hemolysis while maintaining splenic function. The laparoscopic approach is safe and effective and should be considered the procedure of choice in hereditary microspherocytosis. Laparoscopic subtotal splenectomy presents an advantage over open subtotal splenectomy, resulting in decreased blood loss, shorter hospital stay, no conversions, fewer operative and postoperative complications, and excellent remission rates. On the basis of our experience, the preservation of the lower pole of the spleen seems to be a first-line option for the optimal evaluation of the residual splenic mass.

The decisive role of the patient-side surgeon in robotic surgery

IntroductionMinimally invasive technology literature is mainly concerned about the feasibility of the robotic procedures and the performance of the console surgeon. However, few of these technologies could be applied without a well-trained team. Our goal was to demonstrate that robotic surgery depends more on the patient-side assistant surgeon’s abilities than has been previously reported.MethodsIn our department, 280 interventions in digestive, thoracic, and gynecological surgery were performed since the acquisition of the robotic equipment. There are three teams trained in robotic surgery with three console surgeons and four certified patient-side surgeons. Four more patient-side assistants were trained at our center. Trocar placement, docking and undocking of the robot, insertion of the laparoscopic instruments, and hemostatic maneuvers with various devices were quantified and compared.ResultsAssistants trained by using animal or cadaver surgery are more comfortable with the robotic instruments handling and with docking and undocking of the robot. Assistants who finalized their residency or attend their final year are more accurate with the insertion of the laparoscopic instrument to the targeted organ and more skillful with LigaSure or clip applier devices. Interventions that require vivid participation of the assistants have shorter assistant-depending time intervals at the end of the learning curve than at the beginning.ConclusionsRobotic surgery is a team effort and is greatly dependant on the performance of assistant surgeons. Interventions that have the benefit of a trained team are more rapid and secure.

MicroRNAs and ceRNAs: therapeutic implications of RNA networks

Introduction: A new concept of gene regulation, in which competitive endogenous RNAs (ceRNAs) compete for common microRNAs (miRNAs), suggests that mRNA targets have an active role as key elements in the regulation of miRNA availability within cells. ceRNAs are considered to be natural decoys of miRNA activity and can influence the expression of multiple miRNAs. Areas covered: A new complex network of indirect interaction among the RNA transcripts competing for the same pool of miRNAs has been described; in this network, the nodes are the targets, and the links between the nodes are the miRNAs the targets have in common, which form smaller subnetworks. The incidence, state and severity of cancer can be evaluated on the basis of this network signature. The study of these new genome-scale regulatory networks involving miRNAs and ceRNAs may provide information that researchers can use to fine-tune these networks to improve responses to cancer therapy and/or develop new therapeutic interventions. Expert opinion: Combinational approaches based on complex regulatory ceRNA networks (ceRNETs) may be one of the most promising strategies for silencing important mediators of cancer-promoting pathways. Targeting a single miRNA may in fact represent a combined intervention that acts on the feedback and compensatory pathways that can impair treatment response or cause treatment resistance.

Genetic chaos and antichaos in human cancers.

Cancer is considered the genetic disease with the most complex pathogenetic mechanism. Contrary to normal human tissues, which function in a highly ordered and uniform manner, tumor tissues were considered to develop chaos. Here we propose that analysis of human neoplasia according to the concepts of chaos and antichaos allowed to distinguish two main types of cancers: the hematopoietic cancers, characterized by the orderly antichaos and solid cancers governed by a disordered complex of genetic and molecular events characteristic of a chaotic pattern. Genetic chaos and antichaos have generated rules that can be applied to the diagnosis and therapy of human tumors.

Cellular and Kaposi's sarcoma-associated herpes virus microRNAs in sepsis and surgical trauma.

Once a patient is in septic shock, survival rates drop by 7.6% for every hour of delay in antibiotic therapy. Biomarkers based on the molecular mechanism of sepsis are important for timely diagnosis and triage. Here, we study the potential roles of a panel of cellular and viral miRNAs as sepsis biomarkers. We performed genome-wide microRNA (miRNA) expression profiling in leukocytes from septic patients and nonseptic controls, combined with quantitative RT-PCR in plasmas from two cohorts of septic patients, two cohorts of nonseptic surgical patients and healthy volunteers. Enzyme-linked immunosorbent assay, miRNA transfection and chromatin immunoprecipitation were used to study the effects of Kaposi sarcoma herpes virus (KSHV) miRNAs on interleukins secretion. Differences related to sepsis etiology were noted for plasma levels of 10 cellular and 2 KSHV miRNAs (miR-K-10b and miR-K-12-12*) between septic and nonseptic patients. All the sepsis groups had high KSHV miRNAs levels compared with controls; Afro-American patients had higher levels of KSHV-miR-K12-12* than non-Afro-American patients. Both KSHV miRNAs were increased on postoperative day 1, but returned to baseline on day 7; they acted as direct agonists of Toll-like receptor 8 (TLR8), which might explain the increased secretion of the IL-6 and IL-10. Cellular and KSHV miRNAs are differentially expressed in sepsis and early postsurgical patients and may be exploited for diagnostic and therapeutic purposes. Increased miR-K-10b and miR-K12-12* are functionally involved in sepsis as agonists of TLR8, forming a positive feedback that may lead to cytokine dysregulation.

Entirely robotic total pelvic exenteration.

Objective We present an entirely robotic total pelvic exenteration and extended lymphadenectomy with “barreled ureterocutaneostomy” and end colostomy for recurrent endometrial cancer. In 1948, Brunschwig first described a pelvic exenteration as treatment of advanced recurrent malignancy in the pelvis. Currently it represents the only potentially curative option for patients with recurrent endometrial cancer. Methods A 69-year-old female with perineal recurrence invading urethral and vaginal walls, lower rectum and anal sphincter was the perfect candidate for total pelvic exenteration. Results Total operative time was 250 minutes, with a console time of 175 minutes. The estimated blood loss was 365 mL. Conclusions Good oncological results are expected after robotic total pelvic exenteration owing to the accurate, precise dissection and the extension of lymphadenectomy in the narrow space of the deep pelvis similar to robotic prostatectomy and total mesorectal excision.

Robotic spleen-preserving distal pancreatectomy. A case report.

Abstract Distal pancreatectomy (DP) is the removal of the pancreatic tissue at the left side of the superior mesenteric vein and it is traditionally approached by an open or laparoscopic exposure. Preservation of the spleen is optional but appears to have a better immunological outcome. We present the case of a 53-year old patient with a 2.4/2.2 tumor located in the tail of the pancreas, with high tumour marker values for whom we decided to perform a robotic spleen-preserving distal pancreatectomy (RSPDP). The postoperative outcome was satisfactory. In conclusion, we recommend this type of approach for small pancreatic tail lesions.

Robotic surgery of locally advanced gastric cancer -- an initial experience.

Abstract Background : The treatment of gastric cancer is currently based on open gastric resection and regional lymph node dissection. Although the minimally invasive approach is currently being adopted for ever more complex procedures in order to improve post-operative outcomes, the laparoscopic radical D2 gastrectomy has not yet gained a wide acceptance, it being considered one of the most difficult operations in general surgery. Robotic surgery is better than the conventional laparoscopic approach, in that it avoids some of its limitations. Wristed instruments with seven degrees of freedom, the tremor filtering system, the ability to scale motion, and tridimensional vision improve the surgeons’ dexterity when a fine manipulation of tissues in a narrow, fixed operating field or handsewn sutures are required. This study will attempt to evaluate the feasibility of robotic total and subtotal gastrectomy for locally advanced gastric cancer. Methods : Two patients with locally advanced gastric adenocarcinoma underwent robot-assisted gastrectomy with D2 lymph node dissection, with no open or laparoscopic conversion. Results: The post-operative evolution was uneventful and they were both discharged without complications. The number of lymph nodes retrieved was comparable to open surgery. Currently, after a follow-up period of 23 and 26 months respectively, both patients are disease-free. Conclusions : Robotic surgery can be a simpler way of expanding the indications of minimally invasive surgery so as to include the advanced gastric cancer. However, controlled prospective studies are needed in order to evaluate the role of robotics in the management of gastric cancer.

Key principles of miRNA involvement in human diseases

Although rapid progress in our understanding of the functions of miRNA has been made by experimentation and computational approach, a considerable effort still has to be done in determining the general principles that govern the miRNA’s mode of action in human diseases. We will further discuss how these principles are being progressively approached by molecular studies, as well as the importance of miRNA in regulating different target genes and functions in specific biological contexts. There is a great demand to understand the principles of context-specific miRNA target recognition in order to design future experiments and models of normal developmental and disease states.