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1.
HPB (Oxford) ; 23(11): 1700-1707, 2021 11.
Article En | MEDLINE | ID: mdl-34023210

BACKGROUND: The application of intra-operative blood salvage autotransfusion(IBSA) in liver transplantation(LT) for hepatocellular carcinoma(HCC) remains controversial due to the theoretical risk of tumour cell(TC) reintroduction. Current studies evaluating for presence of TC are limited by suboptimal detection techniques. This study aims to analyze the presence of TC in HCC LT autologous blood using microfluidics technology. METHODS: A prospective study of HCC patients who underwent LT from February 2018-April 2019 was conducted. Blood samples were collected peri-operatively. TCs were isolated using microfluidics technology and stained with antibody cocktails for confirmation. RESULTS: A total of 15 HCC LT patients were recruited. All recipients had tumour characteristics within the University of California, San Francisco(UCSF) criteria pre-operatively. TC was detected in all of the autologous blood samples collected from the surgical field. After IOCS wash, five patients had no detectable TC, while 10 patients had detectable TC; of these two remained positive for TC after Leukocyte Depletion Filter(LDF) filtration. CONCLUSION: The risk of tumour cell reintroduction using IBSA in HCC LT patients can be reduced with a single LDF. Future studies should evaluate the proliferation capacity and tumorigenicity of HCC TC in IBSA samples, and the effects of TC reintroduction in patients with pre-existing HCC TCs.


Carcinoma, Hepatocellular , Liver Neoplasms , Liver Transplantation , Operative Blood Salvage , Blood Transfusion, Autologous , Carcinoma, Hepatocellular/surgery , Humans , Liver Neoplasms/surgery , Liver Transplantation/adverse effects , Microfluidics , Neoplasm Recurrence, Local , Prospective Studies , Retrospective Studies
2.
Ann Oncol ; 31(9): 1207-1215, 2020 09.
Article En | MEDLINE | ID: mdl-32422171

BACKGROUND: The tropomyosin receptor kinase (TRK) pathway controls appetite, balance, and pain sensitivity. While these functions are reflected in the on-target adverse events (AEs) observed with TRK inhibition, these AEs remain under-recognized, and pain upon drug withdrawal has not previously been reported. As TRK inhibitors are approved by multiple regulatory agencies for TRK or ROS1 fusion-positive cancers, characterizing these AEs and corresponding management strategies is crucial. PATIENTS AND METHODS: Patients with advanced or unresectable solid tumors treated with a TRK inhibitor were retrospectively identified in a search of clinical databases. Among these patients, the frequency, severity, duration, and management outcomes of AEs including weight gain, dizziness or ataxia, and withdrawal pain were characterized. RESULTS: Ninety-six patients with 15 unique cancer histologies treated with a TRK inhibitor were identified. Weight gain was observed in 53% [95% confidence interval (CI), 43%-62%] of patients and increased with time on TRK inhibition. Pharmacologic intervention, most commonly with glucagon-like peptide 1 analogs or metformin, appeared to result in stabilization or loss of weight. Dizziness, with or without ataxia, was observed in 41% (95% CI, 31%-51%) of patients with a median time to onset of 2 weeks (range, 3 days to 16 months). TRK inhibitor dose reduction was the most effective intervention for dizziness. Pain upon temporary or permanent TRK inhibitor discontinuation was observed in 35% (95% CI, 24%-46%) of patients; this was more common with longer TRK inhibitor use. TRK inhibitor reinitiation was the most effective intervention for withdrawal pain. CONCLUSIONS: TRK inhibition-related AEs including weight gain, dizziness, and withdrawal pain occur in a substantial proportion of patients receiving TRK inhibitors. This safety profile is unique relative to other anticancer therapies and warrants careful monitoring. These on-target toxicities are manageable with pharmacologic intervention and dose modification.


Protein-Tyrosine Kinases , Receptor, trkA , Humans , Proto-Oncogene Proteins , Pyrazoles , Pyrimidines , Retrospective Studies
3.
Ann Oncol ; 29(12): 2302-2312, 2018 12 01.
Article En | MEDLINE | ID: mdl-30016395

Urothelial malignancies, including carcinomas of the bladder, ureters, and renal pelvis comprised ∼8% of new cancer cases in the USA in 2016. In the metastatic setting, 15% of patients exhibit long-term survival following cisplatin-based chemotherapy and in patients with recurrent disease, response rates to second-line chemotherapy are generally 15%-20% with a 3-month progression-free survival. However, recent advances in immunotherapy represent an opportunity to significantly improve patient outcomes. Moreover, the advent of next-generation sequencing has resulted in both an improved understanding of the fundamental genetic changes that characterize urothelial carcinoma (UC) and identification of several candidate biomarkers of response to various therapies. Incorporation of prospective genotyping into clinical trials will allow for the identification and enrichment of patients most likely to respond to specific targeted therapies and chemotherapy. Combining different therapeutic classes to enhance outcomes is also an area of active research in UC.


Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/genetics , Carcinoma, Transitional Cell/drug therapy , Urologic Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Biomarkers, Tumor/antagonists & inhibitors , Carcinoma, Transitional Cell/genetics , Carcinoma, Transitional Cell/mortality , Carcinoma, Transitional Cell/pathology , Clinical Trials as Topic , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/genetics , Genotyping Techniques , High-Throughput Nucleotide Sequencing , Humans , Molecular Targeted Therapy/methods , Mutation Rate , Progression-Free Survival , Urologic Neoplasms/genetics , Urologic Neoplasms/pathology , Urothelium/pathology
4.
Urol Oncol ; 36(7): 345-346, 2018 07.
Article En | MEDLINE | ID: mdl-29859727

PURPOSE: Platinum-based chemotherapy remains the standard treatment for advanced urothelial carcinoma by inducing DNA damage. We hypothesize that somatic alterations in DNA damage response and repair (DDR) genes are associated with improved sensitivity to platinum-based chemotherapy. EXPERIMENTAL DESIGN: Patients with diagnosis of locally advanced and metastatic urothelial carcinoma treated with platinum-based chemotherapy who had exon sequencing with the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) assay were identified. Patients were dichotomized based on the presence/absence of alterations in a panel of 34 DDR genes. DDR alteration status was correlated with clinical outcomes and disease features. RESULTS: One hundred patients were identified, of which 47 harbored alterations in DDR genes. Patients with DDR alterations had improved progression-free survival (9.3 vs. 6.0 months, log-rank P = 0.007) and overall survival (23.7 vs. 13.0 months, log-rank P = 0.006). DDR alterations were also associated with higher number mutations and copy-number alterations. A trend toward positive correlation between DDR status and nodal metastases and inverse correlation with visceral metastases were observed. Different DDR pathways also suggested variable effect on clinical outcomes. CONCLUSIONS: Somatic DDR alteration is associated with improved clinical outcomes in platinum-treated patients with advanced urothelial carcinoma. Once validated, it can improve patient selection for clinical practice and future study enrollment.


Carcinoma, Transitional Cell , Platinum , DNA Damage , Humans , Mutation , Urologic Neoplasms
6.
Minerva Chir ; 72(6): 455-463, 2017 Dec.
Article En | MEDLINE | ID: mdl-28621510

BACKGROUND: There is an increasing preference for early laparoscopic cholecystectomy (ELC) as compared to delayed LC (DLC) in the management of acute cholecystitis (AC). Conversion to open cholecystectomy (LOC) remains an important outcome. We aim to compare ELC and DLC outcomes and identify LOC predictors. METHODS: Retrospective analysis of 466 patients who underwent LC for AC from June 2010 to June 2015 was performed. Patients were divided into ELC and DLC groups, defined as LC performed within 7 days and between 4 to 24 weeks of symptom onset, respectively. Peri-operative outcomes and predictors for LOC were analyzed. RESULTS: Conversion rates were comparable [ELC, 8.6% vs. DLC, 8.0%] (P=0.867). While median operative time was longer in ELC (101.5 min [83.0-130.1]) than DLC (88.0 min [62.3-118.8]) (P<0.001), intraoperative (ELC, 1.9% vs. DLC, 3.0%; P=0.541) and postoperative morbidity (ELC, 13.5% vs. DLC, 12.5%; P=0.688) was comparable. Median total length of stay (LOS) was shorter in ELC (4 days [3-6]) than DLC (5 days [4-9]) (P<0.001). Univariate analysis showed increased age (LC, 57 [45-66] vs. LOC, 60 [56-72]; P=0.016), presence of comorbidities (LC, 69.0% vs. LOC, 87.8%; P=0.009), previous abdominal surgery (LC, 6.1% vs. LOC, 17.1%; P=0.014), fever (P=0.001), Murphy's sign (P=0.005) and lower albumin (LC, 42.0 [39.0-45.0] vs. LOC, 40.0 [36.0-43.0]; P=0.003) to be predictors for LOC. CONCLUSIONS: ELC provides shorter LOS and eliminates the risk of gallstone-related morbidity while awaiting surgery. It should be advocated for patients with AC. The presence of comorbidities, increased age, previous abdominal surgery and low albumin are predictors for conversion.


Cholecystectomy, Laparoscopic , Cholecystitis, Acute/surgery , Operative Time , Patient Selection , Adult , Aged , Body Mass Index , Cholecystectomy , Cholecystectomy, Laparoscopic/methods , Cholecystitis, Acute/diagnosis , Conversion to Open Surgery/methods , Female , Hospitals, University , Humans , Length of Stay , Male , Middle Aged , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome
7.
J Gastrointest Surg ; 21(5): 840-845, 2017 May.
Article En | MEDLINE | ID: mdl-28243979

INTRODUCTION: Studies have shown that same-admission laparoscopic cholecystectomy (SALC) is superior to delayed laparoscopic cholecystectomy (DLC) for acute cholecystitis (AC). However, no studies have compared both modalities in patients with delayed presentation. The aim of the study was to compare outcomes between SALC and DLC in AC patients with more than 7-day symptom duration. METHODS: A retrospective analysis of 83 AC patients who underwent LC after presenting with >7 days of symptoms from June 2010 to June 2015 was performed. Patients were divided into L-SALC and L-DLC, defined as LC performed within the same admission and between 4 and 24 weeks after discharge, respectively. Peri-operative outcomes were evaluated. RESULTS: In L-SALC patients, the intra-operative severity was higher (p < 0.001) and median operative time was longer (L-SALC, 107 min (46-220) vs L-DLC, 95 mins (25-186)) (p = 0.048). Conversion rates were also higher in L-SALC than that in L-DLC (L-SALC, 21.4% vs L-DLC, 4.9%) (p = 0.048). While post-operative morbidity was similar, L-SALC was associated with a longer post-operative length of stay as compared to L-DLC (L-SALC, 2 (1-17) vs L-DLC, 1 (1-6)) (p < 0.001). CONCLUSION: DLC provides lower conversion rates and shorter length of stay in AC patients presenting beyond 7 days of symptoms. This group of patients should be offered DLC.


Cholecystectomy, Laparoscopic , Cholecystitis, Acute/surgery , Adult , Aged , Aged, 80 and over , Conversion to Open Surgery , Female , Hospitalization , Humans , Length of Stay , Male , Middle Aged , Operative Time , Retrospective Studies , Time Factors
8.
HPB (Oxford) ; 19(1): 47-51, 2017 01.
Article En | MEDLINE | ID: mdl-27825751

BACKGROUND: Studies have shown that same admission laparoscopic cholecystectomy (SALC) is superior to delayed laparoscopic cholecystectomy for acute cholecystitis (AC). While some proposed a"golden 72-hour" for SALC, the optimal timing remains controversial. The aim of the study was to compare the outcomes of SALC in AC patients with different time intervals from symptom onset. METHODS: A retrospective analysis of 311 patients who underwent SALC for AC from June 2010-June 2015 was performed. Patients were divided into three groups based on the time interval between symptom onset and surgery: <4 days (E-SALC), 4-7 days (M-SALC), >7 (L-SALC). RESULTS: The mean duration of symptoms was 2(1-3), 5(4-7) and 9 (8-13) days for E-SALC, M-SALC and L-SALC, respectively (p < 0.001). Conversion rates were higher in the L-SALC group [E-SALC, 8.2% vs M-SALC, 9.6% vs L-SALC, 21.4%] (p = 0.048). The total length of stay was longer in patients with longer symptom duration [E-SALC, 4 (2-33) vs M-SALC, 2 (2-23) vs L-SALC, 7 (2-49)] (p < 0.001). CONCLUSION: Patients with AC presenting beyond 7 days of symptoms have higher conversion rates and longer length of stay associated with SALC. However, patients with less than a week of symptoms should be offered SALC.


Cholecystectomy, Laparoscopic , Cholecystitis, Acute/surgery , Patient Admission , Time-to-Treatment , Adult , Aged , Aged, 80 and over , Cholecystectomy, Laparoscopic/adverse effects , Cholecystitis, Acute/diagnosis , Female , Humans , Length of Stay , Male , Middle Aged , Retrospective Studies , Time Factors , Treatment Outcome , Young Adult
9.
Indian J Med Microbiol ; 34(4): 536-538, 2016.
Article En | MEDLINE | ID: mdl-27934839

Recent studies indicate that hepatitis C virus (HCV) proteins can mediate innate immune response and inflammation in conjunctival fibroblasts which contributes to the pathology of dry eye condition associated with chronic HCV infection. The present study investigates the phagocytic potential of human conjunctival fibroblasts (HCFj) for HCV core protein. HCFj cells were incubated with HCV core antigen for different periods of time, and fluorescent micrographs were taken to observe protein internalisation. HCFj cells were capable of internalising HCV core antigen within 1 h; this gives an insight into another molecular mechanism which may contribute towards HCV-associated conjunctival inflammation.


Endocytosis , Fibroblasts/physiology , Viral Core Proteins/metabolism , Cells, Cultured , Conjunctiva/cytology , Humans , Male , Middle Aged
10.
HPB (Oxford) ; 17(11): 988-93, 2015 Nov.
Article En | MEDLINE | ID: mdl-26334002

BACKGROUND: The surgical management of giant hepatocellular carcinoma (G-HCC), or HCC of ≥10 cm in diameter, remains controversial. The aim of this study was to compare the outcomes of surgical resection of, respectively, G-HCC and small HCC (S-HCC), or HCC measuring <10 cm. METHODS: A retrospective review of all patients (n = 86) diagnosed with HCC and submitted to resection in a tertiary hospital during the period from January 2007 to June 2012 was conducted. Overall survival (OS), recurrence rates and perioperative mortality at 30 days were compared between patients with, respectively, G-HCC and S-HCC. Prognostic factors for OS were analysed. RESULTS: The sample included 23 patients with G-HCC (26.7%) and 63 with S-HCC (73.3%) based on histological tumour size. Patient demographics and comorbidities were comparable. Median OS was 39.0 months in patients with G-HCC and 65.0 months in patients with S-HCC (P = 0.213). Although size did not affect OS in this cohort, the presence of satellite lesions [hazard ratio (HR) 3.70, P = 0.012] and perioperative blood transfusion (HR 2.85, P = 0.015) were negative predictors for OS. CONCLUSIONS: Surgical resection of G-HCC provides OS comparable with that after resection of S-HCC.


Carcinoma, Hepatocellular/surgery , Hepatectomy/methods , Liver Neoplasms/surgery , Liver/anatomy & histology , Neoplasm Staging , Postoperative Complications/epidemiology , Tertiary Care Centers , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/mortality , Female , Follow-Up Studies , Humans , Incidence , Liver/surgery , Liver Neoplasms/diagnosis , Liver Neoplasms/mortality , Male , Middle Aged , Organ Size , Prognosis , Retrospective Studies , Risk Factors , Singapore/epidemiology , Survival Rate/trends , Time Factors , Tomography, X-Ray Computed , Treatment Outcome
12.
Ann Oncol ; 24(9): 2414-21, 2013 Sep.
Article En | MEDLINE | ID: mdl-23897706

BACKGROUND: Variations in urothelial carcinoma (UC) response to platinum chemotherapy are common and frequently attributed to genetic and epigenetic variations of somatic DNA. We hypothesized that variations in germline DNA may contribute to UC chemosensitivity. PATIENTS AND METHODS: DNA from 210 UC patients treated with platinum-based chemotherapy was genotyped for 80 single nucleotide polymorphisms (SNPs). Logistic regression was used to examine the association between SNPs and response, and a multivariable predictive model was created. Significant SNPs were combined to form a SNP score predicting response. Eleven UC cell lines were genotyped as validation. RESULTS: Six SNPs were significantly associated with 101 complete or partial responses (48%). Four SNPs retained independence association and were incorporated into a response prediction model. Each additional risk allele was associated with a nearly 50% decrease in odds of response [odds ratio (OR) = 0.51, 95% confidence interval 0.39-0.65, P = 1.05 × 10(-7)). The bootstrap-adjusted area under the curves of this model was greater than clinical prognostic factors alone (0.78 versus 0.64). The SNP score showed a positive trend with chemosensitivity in cell lines (P = 0.115). CONCLUSIONS: Genetic variants associated with response of UC to platinum-based therapy were identified in germline DNA. A model using these genetic variants may predict response to chemotherapy better than clinical factors alone.


Carboplatin/therapeutic use , Cisplatin/therapeutic use , Drug Resistance, Neoplasm/genetics , Urologic Neoplasms/drug therapy , Urologic Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/genetics , Female , Genetic Association Studies , Genetic Variation , Genotype , Germ-Line Mutation/genetics , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide , Treatment Outcome , Urologic Neoplasms/mortality , Urothelium/pathology
14.
Appl Biochem Biotechnol ; 169(3): 1026-38, 2013 Feb.
Article En | MEDLINE | ID: mdl-23296805

The chemical modification of developed ethyl cellulose-based membrane was carried out to make it suitable for bioseparation. The different reagents were used for the modification of membrane to couple protein A (PA) to study the purification of immunoglobulin G (IgG) from blood. The chemical modification was carried out using relatively simple and mild reaction conditions. The attenuated total reflectance Fourier transform infrared analysis of chemically modified membrane showed new peak at 1,596.06 and 1,716.49 cm⁻¹. The scanning electron microscopy of PA-coupled membrane, which was used for IgG purification showed open pores and 950 ± 21.5 LMH (L m⁻² h⁻¹) operational flux at 0.5-bar out pressure. The flux of unmodified membrane was 1,746 ± 18.5 LMH at 0.5-bar out pressure. The equilibrium adsorption concentration (318.5 ± 5.9 µg cm⁻²) was obtained at 3 h. The adsorption character of PA-coupled membrane was consistent with the Langmuir adsorption model and the non-specific binding was 67.08 ± 1.3 µg cm⁻². The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed similar purification pattern for purified IgG from human serum and commercial preparation of IgG. All the results have suggested a high potential of PA-coupled ethyl cellulose-based membrane for large-scale purification of IgG.


Cellulose/analogs & derivatives , Immunoglobulin G/chemistry , Immunoglobulin G/isolation & purification , Cellulose/chemistry , Membranes, Artificial
15.
FEMS Microbiol Rev ; 35(1): 124-46, 2011 Jan.
Article En | MEDLINE | ID: mdl-20584083

Cystic fibrosis (CF), the most common autosomal recessive disorder in Caucasians, and chronic obstructive pulmonary disease (COPD), a disease of adults, are characterized by chronic lung inflammation, airflow obstruction and extensive tissue remodelling, which have a major impact on patients' morbidity and mortality. Airway inflammation is stimulated in CF by chronic bacterial infections and in COPD by environmental stimuli, particularly from smoking. Pseudomonas aeruginosa is the major bacterial pathogen in CF, while in COPD, Haemophilus influenzae is most frequently observed. Molecular studies indicate that during chronic pulmonary infection, P. aeruginosa clones genotypically and phenotypically adapt to the CF niche, resulting in a highly diverse bacterial community that is difficult to eradicate therapeutically. Pseudomonas aeruginosa clones from COPD patients remain within the airways only for limited time periods, do not adapt and are easily eradicated. However, in a subgroup of severely ill COPD patients, P. aeruginosa clones similar to those in CF persist. In this review, we will discuss the pathophysiology of lung disease in CF and COPD, the complex genotypic and phenotypic adaptation processes of the opportunistic bacterial pathogens and novel treatment options.


Bacteria/pathogenicity , Bacterial Infections/microbiology , Cystic Fibrosis/complications , Pneumonia, Bacterial/microbiology , Pulmonary Disease, Chronic Obstructive/complications , Respiratory Tract Infections/microbiology , Adaptation, Biological , Bacteria/genetics , Bacterial Physiological Phenomena , Chronic Disease , Humans , Stress, Physiological
16.
Proc Natl Acad Sci U S A ; 106(52): 22287-92, 2009 Dec 29.
Article En | MEDLINE | ID: mdl-20018714

Super-resolution optical microscopy is a rapidly evolving area of fluorescence microscopy with a tremendous potential for impacting many fields of science. Several super-resolution methods have been developed over the last decade, all capable of overcoming the fundamental diffraction limit of light. We present here an approach for obtaining subdiffraction limit optical resolution in all three dimensions. This method relies on higher-order statistical analysis of temporal fluctuations (caused by fluorescence blinking/intermittency) recorded in a sequence of images (movie). We demonstrate a 5-fold improvement in spatial resolution by using a conventional wide-field microscope. This resolution enhancement is achieved in iterative discrete steps, which in turn allows the evaluation of images at different resolution levels. Even at the lowest level of resolution enhancement, our method features significant background reduction and thus contrast enhancement and is demonstrated on quantum dot-labeled microtubules of fibroblast cells.


Microscopy, Fluorescence/methods , 3T3 Cells , Animals , Biophysical Phenomena , Fibroblasts/ultrastructure , Fluorescent Dyes , Imaging, Three-Dimensional , Mice , Microscopy, Fluorescence/instrumentation , Microscopy, Fluorescence/statistics & numerical data , Microtubules/ultrastructure , Models, Theoretical , Optical Phenomena , Quantum Dots
17.
Neurol India ; 55(3): 260-6, 2007.
Article En | MEDLINE | ID: mdl-17921655

Opportunistic fungal infections are major causes of morbidity and mortality in the immunocompromized. Fungi have evolved complex and coordinated mechanisms to survive in the environment and the mammalian host. Fungi must adapt to "stressors" in the host, including nutrient scarcity, pH and reactive oxygen and nitrogen intermediates, in addition to evading host immunity. Knowledge of the immunopathogenesis of fungal infections has paved the way to promising strategies for immunotherapy. These include strategies that increase phagocyte number, activate innate host defense pathways in phagocytes and dendritic cells and stimulate antigen-specific immunity (e.g, vaccines). Immunotherapy must be tailored to specific immunocompromized states. Our review focuses on cryptococcosis and coccidioidomycosis because of the propensity of these diseases to involve the central nervous system (CNS). The CNS has long been considered "immunologically privileged" in the sense of being isolated from normal immune surveillance. This notion is only partially accurate. Immune-based therapies for fungal CNS disease are at an exploratory level and merit further evaluation in clinical trials.


Central Nervous System Fungal Infections/immunology , Central Nervous System Fungal Infections/therapy , Immunotherapy/methods , Humans
18.
J Agric Saf Health ; 13(1): 33-43, 2007 Jan.
Article En | MEDLINE | ID: mdl-17370912

This article discusses the pollution caused by chrome composite leather-clad (CCLC) rollers commonly used in cotton roller ginning mills and suggests an alternative roller material. CCLC rollers contain about 18,000 to 36,000 mg/kg (ppm) total chromium in trivalent and hexavalent forms, which are toxic to human health and carcinogenic. When seed-cotton is processed in double roller (DR) ginning machines, the lint is contaminated with chromium, and chromium particles are carried into the spun yarns and cotton by-products. Specifically, due to persistent rubbing of the leather-clad roller over the stationary knife during the ginning process, the lint is contaminated with about 140 to 1990 ppm of chromium, and the spun yarns and cotton by-products contain about 100 to 200 ppm, far in excess of the standard limit of 0.1 ppm. Gin and mill workers are directly exposed to this carcinogenic substance. To offset this problem, pollution-free rubberized cotton fabric (RCF) rollers have been fabricated and tested in roller gins. The RCF roller covering is made of multiple layers of fabric bonded together using a white rubber compound, which has a surface finish conducive to high ginning efficiency. This eliminates chromium contamination and pollution during the ginning process. On the basis of the design and development of various test rollers and subsequent evaluation studies, the performance of pollution-free RCF rollers has been demonstrated with reference to their commercial benefit and eco-friendliness in cotton ginning mills.


Agriculture/instrumentation , Chromium/toxicity , Environmental Pollution/prevention & control , Gossypium/chemistry , Occupational Diseases/chemically induced , Trace Elements/toxicity , Carcinogens/toxicity , Cotton Fiber , Humans , Rubber , Textiles
20.
Article En | MEDLINE | ID: mdl-29176922

We have developed a new functionalization approach for semiconductor nanocrystals based on a single-step exchange of surface ligands with custom-designed peptides. This peptide-coating technique yield small, monodisperse and very stable water-soluble NCs that remain bright and photostable. We have used this approach on several types of core and core-shell NCs in the visible and near-infrared spectrum range and used fluorescence correlation spectroscopy for rapid assessment of the colloidal and photophysical properties of the resulting particles. This peptide coating strategy has several advantages: it yields probes that are immediately biocompatible; it is amenable to improvements of the different properties (solubilization, functionalization, etc) via rational design, parallel synthesis, or molecular evolution; it permits the combination of several functions on individual NCs. These functionalized NCs have been used for diverse biomedical applications. Two are discussed here: single-particle tracking of membrane receptor in live cells and combined fluorescence and PET imaging of targeted delivery in live animals.

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