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1.
Mass Spectrom Rev ; 40(5): 670-691, 2021 09.
Article in English | MEDLINE | ID: mdl-32949473

ABSTRACT

Mass spectrometry (MS) has played a remarkable role in exploring the chemical make-up of our solar system. In situ probes were historically developed to analyze inorganic/elemental compositions while leveraging native ions or harsh ionization methods to aid in exploring astrophysics applications (e.g., heliophysics). The part played by MS is demonstrated in a majority of scientific payloads focused on exploration, particularly at the turn of the century with missions including Cassini-Huygens, Rosetta, and now Mars Science Laboratory. Plasma mass spectrometers have grown more sophisticated to interrogate fundamental inorganic analysis (e.g., solar wind and magnetospheres) including both native ions and neutrals. Cosmic dust floating in-between and orbiting planetary bodies has been targeted by unique sampling via impact ionization. More complex systems rely on landed planetary instrumentation with lessons learned from pioneering missions in the 1970s and 1980s to near neighbors Mars and Venus. Modern probes have expanded applicable target chemicals by recognizing the needs to provide for molecular analyses, extended mass range, and high resolution to provide unequivocal detection and identification. Notably, as the field surrounding astrobiology has gained momentum, so has the in situ detection of complex molecular chemistry including the chemical evolution of organic molecules. Mission context often includes long term timelines from spacecraft launch to arrival and additionally the diverse target environments across various planets. Therefore, customized experimental designs for space MS have been born of necessity. To this point, the development of MS instrumentation on Earth has now far outpaced development for experiments in space. Therefore, exciting developments lie ahead among various international space agencies conducting current and future mission planning with increasingly enhanced instrumentation. For instance, near-neighbor Mars has entertained considerable attention with complex MS instrumentation with laser desorption ionization aboard the Mars Organic Molecule Analyzer instrument. To study comets, the Rosetta mission employs a secondary ionization mechanism. Meanwhile, the various moons of Jupiter and Saturn have intriguing surface and subsurface properties that warrant more advanced analyzer systems. Instrumentation design will continue to evolve as requirements develop and this review serves as a reflection of the contribution of in situ MS to space exploration in the past 20 years and the anticipated contribution yet to come. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.

2.
Anal Chem ; 92(4): 2917-2921, 2020 02 18.
Article in English | MEDLINE | ID: mdl-31976655

ABSTRACT

Due to the widespread abuse of opioids in recent years, the development of quick and reliable methods for analyzing compounds such as fentanyl and its derivatives is increasingly important. Ahead of online mass spectrometric analysis, field asymmetric ion mobility spectrometry (FAIMS) has previously been used for rapid ion prefiltering and demonstrated significantly improved peak capacity with the addition of vapor modifiers to the carrier gas. The application of FAIMS-mass spectrometry (MS) in the analysis of fentanyl and related compounds is presented herein with the use of a water vapor modifier. The inclusion of the water vapor modifier to the FAIMS methodology is made more robust with the incorporation of a humidity sensor. A dramatic improvement in the separation of fentanyl, alfentanil, 4-aminophenyl-1-phenethylpiperidine (4-ANPP), norfentanyl, and heroin has been achieved, and the ability to distinguish the isobars in a mixture, alfentanil and ortho-isopropyl furanyl fentanyl, is demonstrated without lengthy chromatography.

3.
Arab J Urol ; 17(3): 167-180, 2019.
Article in English | MEDLINE | ID: mdl-31489232

ABSTRACT

Objective: To determine the role of lymph node dissection (LND) in the treatment of upper tract transitional cell carcinoma (UTTCC), as the role of LND along with nephroureterectomy in treating UTTCC is unclear and several retrospective studies have been published on this topic with conflicting results. Methods: The Medical Literature Analysis and Retrieval System Online (MEDLINE), the Excerpta Medica dataBASE (EMBASE), Cochrane Central Register of Controlled Trials database (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Clinicaltrials.gov, Google Scholar, and individual urological journals, were searched for all studies investigating the role of LND in the treatment of UTTCC. Of the studies identified, those that met inclusion criteria were included in this review. Results: In all, 27 studies were included in this review, with 9303 patients who underwent LND. No randomised controlled trials (RCTs) were identified. Tumours were located in the renal pelvis in 62% of patients, in the ureter in 35.5%, and multifocal in 2.3%. In total: 77.1% were LN-negative and 22.9% had LN metastasis. For all patients undergoing LND, the 5-year recurrence-free survival (RFS) and cancer-specific survival (CSS) rates were 27-65.4% and 32.3-95%, respectively. For patients who underwent a LND in accordance with a standardised anatomical template, the 5-year RFS and CSS rates were 84.3-93% and 83.5-94%, respectively. Conclusion: LND may provide a survival benefit in patients undergoing nephroureterectomy for UTTCC, particularly if following a standardised anatomical template and in those patients with muscle-invasive disease; however, a prospective RCT is required to confirm this. Abbreviations: CSS: cancer-specific survival; LN(D): lymph node (dissection); MeSH: Medical Subject Headings; OS: overall survival; pT: pathological T stage; RCT: randomised controlled trial; RFS: recurrence-free survival; UTTCC: upper tract TCC.

4.
J Endourol ; 33(4): 263-273, 2019 04.
Article in English | MEDLINE | ID: mdl-30793934

ABSTRACT

INTRODUCTION AND OBJECTIVES: Standard of care in upper tract urothelial cancer is nephroureterectomy with bladder cuff excision (BCE). However, alternative techniques such as transurethral incision/resection have been used to simplify distal ureterectomy. The optimum strategy is unclear, and current guidelines do not specify a gold standard technique. The objective of this study was to perform a systematic review of the literature, to compare BCE and transurethral distal ureter methods. MATERIALS AND METHODS: A Cochrane and PRISMA-guided systematic literature search was conducted on English language articles from January 2000 to present, reporting on centers' experience with either BCE or transurethral distal ureterectomy. A cumulative meta-analysis comparison between the two procedures was performed. Primary outcome was intravesical recurrence. Secondary outcomes were local/distant recurrence, surgical margins, and disease-specific mortality (DSM). Groups were compared using chi-square analysis. RESULTS: In total, 66 studies were included after excluding 1795. BCE and transurethral groups contained 6130 and 1183 patients, respectively. Mean/median age ranged from 57.5 to 75.2 years, and follow-up from 6.1 to 78 months. Level of evidence was low, with high risk of bias and small sample size (<100 patients) in 41 (62%) and 52 (79%) studies, respectively. Baseline cancer demographic analysis identified significantly higher rates of high grade, advanced stage, node-positive and carcinoma in situ disease in the BCE group. However, intravesical recurrence (23.6% vs 28.7%, p = 0.0002) and local/distant recurrence (17.9% vs 21.6%, p = 0.02) were significantly lower than the transurethral group. No difference was seen regarding surgical margins (3.1% vs 2.4%, p = 0.27) or DSM (16.8% vs 14.3%, p = 0.06). CONCLUSIONS: No prospective, randomized comparisons exist for distal ureterectomy at nephroureterectomy. In this analysis, patients undergoing BCE had more advanced disease burden compared with the transurethral group. Despite this, the BCE group had statistically lower intravesical and local/distant recurrence. Further prospective research should be encouraged to identify gold standard ureter management.


Subject(s)
Nephroureterectomy/methods , Ureter/surgery , Ureteral Neoplasms/surgery , Aged , Cystectomy , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/surgery , Recurrence , Robotic Surgical Procedures , SEER Program , United States
5.
Can Urol Assoc J ; 12(7): E345-E348, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29603920

ABSTRACT

INTRODUCTION: Prognosis in patients with cancer is influenced by underlying tumour biology and also the host inflammatory response to the disease. There is limited evidence to suggest that an elevated neutrophil-lymphocyte ratio (NLR) predicts a poorer prognosis in patients undergoing nephrectomy for renal cell carcinoma (RCC). The aim of this paper is to investigate if patients undergoing nephrectomy for RCC with NLR ≤4 have a better overall and recurrence-free survival than patients with NLR >4. METHODS: All patients who underwent nephrectomy at a single centre between January 1, 2011 and December 31, 2014 were identified. Patients were included if postoperative histology demonstrated RCC and if preoperative NLR was available. Patients were excluded if nephrectomy was not curative intent (i.e., cytoreductive nephrectomy), if primary tumour was graded to be T3b-4 disease, if there was presence of nodal or metastatic disease on preoperative staging, or if adequate followup notes were not available. Primary and secondary outcomes were overall survival and recurrence-free survival, respectively. RESULTS: A total of 154 patients were included in analysis of overall survival; 146 patients were included in analysis of recurrence-free survival. Patients with NLR ≤4 had a much better overall survival than patients with NLR >4 (95% vs. 78%; p=0.0219). Patients with NLR >4 also had higher rates of recurrence (p=0.0218). CONCLUSIONS: NLR may be a useful tool in identifying patients who may benefit from more frequent surveillance in the early postoperative period and may allow clinicians to offer surveillance schemes tailored to the individual patient.

6.
Clin Genitourin Cancer ; 14(4): 271-6, 2016 08.
Article in English | MEDLINE | ID: mdl-26949171

ABSTRACT

The objective is to evaluate the prognostic benefit of the Glasgow Prognostic Score (GPS), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and Prognostic Nutrition Index (PNI) in patients with localized renal cell carcinoma undergoing nephrectomy with curative intent. Embase and MEDLINE databases were searched for all publications before April 2015. Duplicates were excluded, and inclusion/exclusion criteria were applied to all abstracts; of those remaining, full articles were obtained and inclusion/exclusion criteria were again applied, and the remaining articles were included and critically appraised. Eight articles were included in this review. Three articles were included for GPS. Outcomes included recurrence-free survival, cancer-specific survival (CSS), and overall survival (OS). All articles demonstrated better prognosis associated with a lower GPS on multivariate analysis: 1-year recurrence-free survival hazard ratio (HR), 7.0 (P = .001); CSS HR, 6.7 to 8.6 (P < .001); and OS HR 4.2 (P < .001). Four articles were included for NLR. All articles demonstrated elevated NLR to be associated with a poorer prognosis. Two articles demonstrated elevated NLR to be associated with a lower progression-free survival. One article demonstrated elevated NLR to be associated with a lower CSS (HR, 1.02, P = .009), and 2 articles demonstrated elevated NLR to be associated with a lower OS (HR, 1.02-1.6). No articles were included for PLR, and only 1 article was identified for PNI. There may be a role for modified GPS and NLR in patients with renal cell carcinoma undergoing nephrectomy with curative intent. Evidence for PLR and PNI is minimal.


Subject(s)
Carcinoma, Renal Cell/blood , Carcinoma, Renal Cell/surgery , Kidney Neoplasms/blood , Kidney Neoplasms/surgery , Female , Humans , Leukocyte Count , Lymphocyte Count , Male , Platelet Count , Survival Analysis
7.
Hepatobiliary Pancreat Dis Int ; 13(5): 474-81, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25308357

ABSTRACT

BACKGROUND: Various scoring systems based on assessment of the systemic inflammatory response help assessing the prognosis of patients with pancreatic ductal adenocarcinoma. In the present systematic review we evaluated the validity of four pre-intervention scoring systems: Glasgow prognostic score (GPS) and its modified version (mGPS), platelet lymphocyte ratio (PLR), neutrophil lymphocyte ratio (NLR), and prognostic nutrition index (PNI). DATA SOURCES: MOOSE guidelines were followed and EMBASE and MEDLINE databases were searched for all published studies until September 2013 using comprehensive text word and MeSH terms. All identified studies were analyzed, and relevant studies were included in the systematic review. RESULTS: Six studies were identified for GPS/mGPS with 3 reporting statistical significance for GPS/mGPS on both univariate analysis (UVA) and multivariate analysis (MVA). Two studies suggested prognostic significance on UVA but not MVA, and in the final study UVA failed to show significance. Eleven studies evaluated the prognostic value of NLR. Six of them reported prognostic significance for NLR on UVA that persisted at MVA in 4 studies, and in the remaining 2 studies NLR was the only significant factor on UVA. In the remaining 5 studies, all in patients undergoing resection, there was no significance on UVA. Seven studies evaluated PLR, with only one study demonstrated its prognostic significance on both UVA and MVA, the rest did not show the significance on UVA. Of the two studies identified for PNI, one demonstrated a statistically significant difference in survival on both UVA and MVA, and the other reported no significance for PNI on UVA. CONCLUSIONS: Both GPS/mGPS and NLR may be useful but further better-designed studies are required to confirm their value. PLR might be little useful, and there are at present inadequate data to assess the prognostic value of PNI. At present, no scoring system is reliable enough to be accepted into routine use for the prognosis of patients with pancreatic ductal adenocarcinoma.


Subject(s)
Adenocarcinoma/blood , Inflammation/blood , Pancreatic Neoplasms/blood , C-Reactive Protein/metabolism , Humans , Lymphocyte Count , Neutrophils , Nutritional Status , Platelet Count , Prognosis , Serum Albumin/metabolism , Severity of Illness Index
8.
Surg Oncol ; 23(4): 177-85, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25263794

ABSTRACT

BACKGROUND: Gastric cancer has a high mortality, with many patients presenting with advanced disease. Many patients who undergo curative gastrectomy will subsequently develop metastatic disease. Hepatectomy has an established place in treating metastases from a variety of cancers but its role in gastric cancer is not clear. This review sought to systematically appraise the literature to establish the role of hepatectomy in treating gastric cancer metastases. METHOD: Medline and EMBASE were searched for all papers publishing data on survival of patients with metastatic gastric adenocarcinoma who underwent hepatectomy. RESULTS: Seventeen studies with 438 patients were included. There were no randomised controlled trials. Perioperative mortality was 2%, with morbidity between 17 and 60%. Patients with solitary metastases appeared to have better survival. Other favourable survival characteristics included unilobar disease, and metachronous presentation. No advantage was demonstrated with either adjuvant or neoadjuvant chemotherapy. DISCUSSION: Few patients with hepatic metastases from gastric cancer are suitable for hepatectomy, but for those suitable there appears to be survival benefit. Patients with synchronous, multiple or bilobar metastases have worse survival. CONCLUSION: The evidence supporting the role of hepatectomy in the treatment of hepatic metastases from gastric cancer is weak. However in a selected group there appears to be a survival advantage; patients with solitary metastases had better survival outcomes than those with multiple metastases and metachronous presentation was associated with a better prognosis than synchronous presentation. Hepatectomy should be considered in these patients in the setting of a randomised trial.


Subject(s)
Adenocarcinoma/surgery , Hepatectomy , Liver Neoplasms/surgery , Stomach Neoplasms/pathology , Adenocarcinoma/drug therapy , Adenocarcinoma/secondary , Chemotherapy, Adjuvant , Hepatectomy/adverse effects , Hepatectomy/mortality , Humans , Liver Neoplasms/drug therapy , Liver Neoplasms/secondary , Neoadjuvant Therapy , Prognosis , Survival Rate
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