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1.
ESMO Open ; 8(3): 101567, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37263081

ABSTRACT

This article summarises expert discussion on the management of patients with hepatocellular carcinoma (HCC), which took place during the 24th World Gastrointestinal Cancer Congress (WGICC) in Barcelona, July 2022. A multidisciplinary approach is mandatory to ensure an optimal diagnosis and staging of HCC, planning of curative and therapeutic options, including surgical, embolisation, ablative strategies, or systemic therapy. Furthermore, in many patients with HCC, underlying liver cirrhosis represents a challenge and influences the therapeutic options.


Subject(s)
Carcinoma, Hepatocellular , Gastrointestinal Neoplasms , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/therapy , Gastrointestinal Neoplasms/diagnosis , Gastrointestinal Neoplasms/therapy , Liver Neoplasms/diagnosis , Liver Neoplasms/therapy , Practice Guidelines as Topic
2.
ESMO Open ; 8(2): 100781, 2023 04.
Article in English | MEDLINE | ID: mdl-36842299

ABSTRACT

BACKGROUND: Following a European Society for Medical Oncology Women for Oncology (ESMO W4O) survey in 2016 showing severe under-representation of female oncologists in leadership roles, ESMO launched a series of initiatives to address obstacles to gender equity. A follow-up survey in October 2021 investigated progress achieved. MATERIALS AND METHODS: The W4O questionnaire 2021 expanded on the 2016 survey, with additional questions on the impact of ethnicity, sexual orientation and religion on career development. Results were analysed according to respondent gender and age. RESULTS: The survey sample was larger than in 2016 (n = 1473 versus 482), especially among men. Significantly fewer respondents had managerial or leadership roles than in 2016 (31.8% versus 51.7%). Lack of leadership development for women and unconscious bias were considered more important in 2021 than in 2016. In 2021, more people reported harassment in the workplace than in 2016 (50.3% versus 41.0%). In 2021, ethnicity, sexual orientation and religion were considered to have little or no impact on professional career opportunities, salary setting or related potential pay gap. However, gender had a significant or major impact on career development (25.5% of respondents), especially in respondents ≤40 years of age and women. As in 2016, highest ranked initiatives to foster workplace equity were promotion of work-life balance, development and leadership training and flexible working. Significantly more 2021 respondents (mainly women) supported the need for culture and gender equity education at work than in 2016. CONCLUSIONS: Gender remains a major barrier to career progression in oncology and, although some obstacles may have been reduced since 2016, we are a long way from closing the gender gap. Increased reporting of discrimination and inappropriate behaviour in the workplace is a major, priority concern. The W4O 2021 survey findings provide new evidence and highlight the areas for future ESMO interventions to support equity and diversity in oncology career development.


Subject(s)
Medical Oncology , Working Conditions , Humans , Male , Female , Sex Factors , Surveys and Questionnaires
3.
Clin Oncol (R Coll Radiol) ; 34(1): 28-35, 2022 01.
Article in English | MEDLINE | ID: mdl-34479769

ABSTRACT

AIMS: Most randomised controlled trials (RCTs) in oncology are now funded by the pharmaceutical industry. We explore the extent to which RCT design, results and interpretation differ between industry-funded and non-industry-funded RCTs. MATERIALS AND METHODS: In this cross-sectional analysis, a structured literature search was used to identify all oncology RCTs published globally during 2014-2017. Industry funding was identified based on explicit statements in the publication. Descriptive statistics were used to compare elements of trial methodology and output between industry- and non-industry-funded RCTs. RESULTS: The study sample included 694 RCTs; 71% were funded by industry. Industry-funded trials were more likely to test systemic therapy (97% versus 62%; P < 0.001), palliative-intent therapy (71% versus 41%; P < 0.001) and study breast cancer (20% versus 12%; P < 0.001). Industry-funded trials were larger (median sample size 474 versus 375; P < 0.001) and more likely to meet their primary end point (49% versus 41%; P < 0.001). Among positive trials, there were no differences in the magnitude of benefit between industry- and non-industry-funded RCTs. Trials funded by industry were published in journals that had a significantly higher median impact factor (21, interquartile range 7, 28) than non-industry-funded trials (impact factor 12, interquartile range 5, 24; P = 0.005); this persisted when adjusted for whether a trial was positive or negative. CONCLUSIONS: The vast majority of oncology RCTs are now funded by industry. Industry-funded trials are larger, more likely to be positive, predominantly test systemic therapies in the palliative setting and are published in higher impact journals than trials without industry support.


Subject(s)
Drug Industry , Medical Oncology , Cross-Sectional Studies , Humans , Randomized Controlled Trials as Topic
4.
Scand J Surg ; 109(3): 228-237, 2020 Sep.
Article in English | MEDLINE | ID: mdl-30931801

ABSTRACT

BACKGROUND AND AIMS: There is no consensus regarding the routine placement of intra-abdominal drains after pancreaticoduodenectomy. We aim to determine the effects of intraperitoneal drain placement during pancreaticoduodenectomy on 30-day postoperative morbidity and mortality. METHODS: Patients who underwent pancreaticoduodenectomy for pancreatic tumors were identified from the 2014-2015 American College of Surgeons-National Surgical Quality Improvement Program Database. Univariate and multivariate analyses adjusting for known prognostic variables were performed. A subgroup analysis was performed based on the risk for development of postoperative pancreatic leak determined by the pancreatic duct caliber, parenchymal texture, and body mass index. RESULTS: A total of 6858 patients with pancreatic tumors who underwent pancreaticoduodenectomy were identified in the 2014-2015 American College of Surgeons-National Surgical Quality Improvement Program Database dataset. In all, 87.4% of patients had intraperitoneal drains placed. A 30-day mortality rate was higher in the no-drain group (2.9% vs. 1.7%, P = 0.003). Patients in the drain group had a higher incidence of overall morbidity (49.5% vs. 41.2%, P = 0.0008), delayed gastric emptying (18.1% vs. 13.7%, P = 0.004), pancreatic fistulae (19.4% vs. 9.9%, P ⩽ 0.0001), and prolonged length of hospital stay over 10 days (43.7% vs. 34.9%, P < 0.0001). Subgroup analysis based on risk categories revealed a higher 30-day mortality rate in the no-drain group among patients with high-risk features (3.1% vs. 1.6%, P = 0.02). Delayed gastric emptying and pancreatic fistula development remained significantly higher in the drain group only in the high-risk category. Prolonged length of hospital stay and composite morbidity remained higher in the drain group regardless of the risk category. CONCLUSION: To our knowledge, this is the largest study to date that aims at clarifying the pros and cons of the intraperitoneal drain placement during pancreaticoduodenectomy for pancreatic tumors. We showed a higher 30-day mortality rate if drain insertion was omitted during pancreaticoduodenectomy in patients with softer pancreatic textures, smaller pancreatic duct caliber, and body mass index over 25. Postoperative 30-day morbidity rate was higher if a drain was inserted regardless of the risk category. Further randomized controlled trials with prospective evaluation of stratification factors for fistula risk are needed to establish a clear recommendation.


Subject(s)
Drainage , Pancreaticoduodenectomy , Perioperative Care/methods , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Adult , Aged , Aged, 80 and over , Databases, Factual , Drainage/adverse effects , Drainage/methods , Female , Humans , Length of Stay/statistics & numerical data , Logistic Models , Male , Middle Aged , Pancreaticoduodenectomy/mortality , Perioperative Care/adverse effects , Postoperative Complications/epidemiology , Risk Assessment , Risk Factors , Treatment Outcome
5.
Clin Radiol ; 70(12): 1382-7, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26392317

ABSTRACT

AIM: To evaluate the association of quantitative computed tomography (CT) measures of emphysema with the occurrence of pneumothorax after CT-guided needle lung biopsy (NLB) accounting for other risk factors. MATERIALS AND METHODS: One hundred and sixty-three CT-guided NLBs performed between 2008 and 2013 with available complete chest CT within 30 days were reviewed for the occurrence of post-procedure pneumothorax. Percent emphysema was determined quantitatively as the percentage of lung voxels below -950 HU on chest CT images using automated software. Multivariable regression was used to assess the association of percent emphysema volume with the occurrence of post-procedure pneumothorax. The association of percent emphysema volume with the pneumothorax size and need for chest tube placement after NLB was also explored. RESULTS: Percent emphysema was significantly associated with the incidence of post-NLB pneumothorax (OR=1.10 95% confidence interval: 1.01-1.15; p=0.03) adjusting for lower-lobe lesion location, needle path length, lesion size, number of passes, and pleural needle trajectory angle. Percent emphysema was not associated with the size of the pneumothorax, nor the need for chest tube placement after NLB. CONCLUSION: Percent emphysema determined quantitatively from chest CT is a significant predictor of post-NLB pneumothorax.


Subject(s)
Pneumothorax/diagnostic imaging , Pneumothorax/pathology , Radiography, Interventional , Biopsy, Needle/methods , Cross-Sectional Studies , Female , Humans , Image-Guided Biopsy/methods , Lung/diagnostic imaging , Lung/pathology , Male , Middle Aged , Predictive Value of Tests , Reproducibility of Results , Risk Factors , Tomography, X-Ray Computed
6.
Clin Radiol ; 70(4): 359-65, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25555314

ABSTRACT

AIM: To test the hypothesis that computed tomography (CT)-based signs might precede symptomatic malignant spinal cord compression (MSCC) in men with metastatic castration-resistant prostate cancer (mCRPC). MATERIALS AND METHODS: A database was used to identify suitable mCRPC patients. Staging CT images were retrospectively reviewed for signs preceding MSCC. Signs of malignant paravertebral fat infiltration and epidural soft-tissue disease were defined and assessed on serial CT in 34 patients with MSCC and 58 control patients. The presence and evolution of the features were summarized using descriptive statistics. RESULTS: In MSCC patients, CT performed a median of 28 days prior to the diagnostic magnetic resonance imaging (MRI) demonstrated significant epidural soft tissue in 28 (80%) patients. The median time to MSCC from a combination of overt malignant paravertebral and epidural disease was 2.7 (0-14.6) months. Conversely, these signs were uncommon in the control cohort. CONCLUSIONS: Significant malignant paravertebral and/or epidural disease at CT precede MSCC in up to 80% of mCRPC patients and should prompt closer patient follow-up and consideration of early MRI evaluation. These CT-based features require further prospective validation.


Subject(s)
Spinal Cord Compression/diagnostic imaging , Spinal Cord Neoplasms/diagnostic imaging , Aged , Case-Control Studies , Humans , Male , Middle Aged , Prostatic Neoplasms, Castration-Resistant/pathology , Retrospective Studies , Spinal Cord Neoplasms/secondary , Tomography, X-Ray Computed
7.
Eur Urol ; 65(2): 270-273, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24295792

ABSTRACT

Metastatic involvement of the viscera in men with advanced castration-resistant prostate cancer (CRPC) has been poorly characterised to date. In 359 CRPC patients treated between June 2003 and December 2011, the frequency of radiologically detected visceral metastases before death was 32%. Of the 92 patients with computed tomography performed within 3 mo of death, 49% had visceral metastases. Visceral metastases most commonly involved the liver (20%) and lung (13%). Median survival from diagnosis of visceral disease was 7.1 mo (95% confidence interval, 5.9-8.3). Survival was affected by the degree of bone involvement at detection of visceral disease, varying from 6.1 mo in men with more than six bone metastases to 18.2 mo in men with no bone metastases (p=0.001). Heterogeneity was noted in clinical phenotypes and prostate-specific antigen trends at development of visceral metastases. Visceral metastases are now more commonly detected in men with CRPC, likely due to the introduction of novel survival-prolonging treatments.


Subject(s)
Bone Neoplasms/secondary , Liver Neoplasms/secondary , Lung Neoplasms/secondary , Prostatic Neoplasms, Castration-Resistant/pathology , Antineoplastic Agents/therapeutic use , Bone Neoplasms/blood , Bone Neoplasms/diagnostic imaging , Bone Neoplasms/drug therapy , Bone Neoplasms/mortality , Humans , Kallikreins/blood , Kaplan-Meier Estimate , Liver Neoplasms/blood , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/drug therapy , Liver Neoplasms/mortality , Lung Neoplasms/blood , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/drug therapy , Lung Neoplasms/mortality , Male , Phenotype , Proportional Hazards Models , Prostate-Specific Antigen/blood , Prostatic Neoplasms, Castration-Resistant/blood , Prostatic Neoplasms, Castration-Resistant/diagnostic imaging , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/mortality , Risk Factors , Time Factors , Tomography, X-Ray Computed , Treatment Outcome
9.
Br J Cancer ; 109(10): 2579-86, 2013 Nov 12.
Article in English | MEDLINE | ID: mdl-24169353

ABSTRACT

BACKGROUND: Prostate cancer remains dependent of androgen receptor (AR) signalling, even after emergence of castration resistance. EZN-4176 is a third-generation antisense oligonucleotide that binds to the hinge region (exon 4) of AR mRNA resulting in full-length AR mRNA degradation and decreased AR protein expression. This Phase I study aimed to evaluate EZN-4176 in men with castration-resistant prostate cancer (CRPC). METHODS: Patients with progressing CRPC were eligible; prior abiraterone and enzalutamide treatment were allowed. EZN-4176 was administered as a weekly (QW) 1-h intravenous infusion. The starting dose was 0.5 mg kg(-1) with a 4-week dose-limiting toxicity (DLT) period and a 3+3 modified Fibonacci dose escalation design. After determination of the DLT for weekly administration, an every 2 weeks schedule was initiated. RESULTS: A total of 22 patients were treated with EZN-4176. At 10 mg kg(-1) QW, two DLTs were observed due to grade 3-4 ALT or AST elevation. No confirmed biochemical or soft tissue responses were observed. Of eight patients with <5 circulating tumour cells at baseline, a conversion to <5 was observed in three (38%) patients. The most common EZN-4176-related toxicities (all grades) were fatigue (59%), reversible abnormalities in liver function tests ALT (41%) and AST (41%) and infusion-related reactions including chills (36%) and pyrexia (14%). CONCLUSION: Activity of EZN-4176 at the doses and schedules explored was minimal. The highest dose of 10 mg kg(-1) QW was associated with significant but reversible transaminase elevation.


Subject(s)
Adenocarcinoma/therapy , Androgen Antagonists/therapeutic use , DNA/therapeutic use , Prostatic Neoplasms/therapy , Receptors, Androgen/genetics , Adenocarcinoma/genetics , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Aged , Aged, 80 and over , Androgen Antagonists/adverse effects , Androgen Antagonists/pharmacokinetics , DNA/adverse effects , DNA/pharmacokinetics , Exons/genetics , Humans , Male , Middle Aged , Oligonucleotides/adverse effects , Oligonucleotides/pharmacokinetics , Oligonucleotides/therapeutic use , Oligonucleotides, Antisense/adverse effects , Oligonucleotides, Antisense/pharmacokinetics , Oligonucleotides, Antisense/therapeutic use , Orchiectomy , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , RNA, Messenger/genetics , Treatment Failure
10.
Br J Cancer ; 109(5): 1079-84, 2013 Sep 03.
Article in English | MEDLINE | ID: mdl-23928659

ABSTRACT

BACKGROUND: Abiraterone is a standard treatment for men with castration-resistant prostate cancer (CRPC). We evaluated the antitumour activity of abiraterone following the synthetic oestrogen diethylstilboestrol (DES). METHODS: Castration-resistant prostate cancer patients treated with abiraterone were identified. Demographics, response variables and survival data were recorded. RESULTS: Two-hundred and seventy-four patients received abiraterone, 114 (41.6%) after DES. Pre-chemotherapy abiraterone resulted in ≥50% PSA declines in 35/41 (85.4%) DES-naïve and 20/27 (74.1%) DES-treated patients. Post-docetaxel abiraterone resulted in ≥50% PSA declines in 40/113 (35.4%) DES-naïve and 23/81 (28.4%) DES-treated patients. Time to PSA progression was similar regardless of prior DES. CONCLUSION: Abiraterone has important antitumour activity in men with CRPC even after DES exposure.


Subject(s)
Androstenols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Diethylstilbestrol/therapeutic use , Estrogens, Non-Steroidal/therapeutic use , Prostatic Neoplasms/drug therapy , Steroid 17-alpha-Hydroxylase/antagonists & inhibitors , Adult , Aged , Aged, 80 and over , Androgen Antagonists/therapeutic use , Androstenes , Antineoplastic Agents/therapeutic use , Disease Progression , Docetaxel , Humans , Male , Middle Aged , Orchiectomy , Prostate-Specific Antigen , Prostatic Neoplasms/surgery , Taxoids/therapeutic use , Treatment Outcome
11.
Br J Cancer ; 109(2): 325-31, 2013 Jul 23.
Article in English | MEDLINE | ID: mdl-23807167

ABSTRACT

BACKGROUND: Standard medical castration reduces muscle mass. We sought to characterize body composition changes in men undergoing maximal androgen suppression with and without exogenous gluocorticoids. METHODS: Cross-sectional areas of total fat, visceral fat and muscle were measured on serial CT scans in a post-hoc analysis of patients treated in Phase I/II trials with abiraterone followed by abiraterone and dexamethasone 0.5 mg daily. Linear mixed regression models were used to account for variations in time-on-treatment and baseline body mass index (BMI). RESULTS: Fifty-five patients received a median of 7.5 months abiraterone followed by 5.4 months abiraterone and dexamethasone. Muscle loss was observed on single-agent abiraterone (maximal in patients with baseline BMI >30, -4.3%), but no further loss was observed after addition of dexamethasone. Loss of visceral fat was also observed on single-agent abiraterone, (baseline BMI >30 patients -19.6%). In contrast, addition of dexamethasone led to an increase in central visceral and total fat and BMI in all the patients. INTERPRETATION: Maximal androgen suppression was associated with loss of muscle and visceral fat. Addition of low dose dexamethasone resulted in significant increases in visceral and total fat. These changes could have important quality-of-life implications for men treated with abiraterone.


Subject(s)
Androgen Antagonists/adverse effects , Androstenols/adverse effects , Body Composition/drug effects , Prostatic Neoplasms/drug therapy , Sarcopenia/chemically induced , Aged , Aged, 80 and over , Androgen Antagonists/administration & dosage , Androstenes , Androstenols/administration & dosage , Antineoplastic Agents, Hormonal/administration & dosage , Antineoplastic Agents, Hormonal/adverse effects , Humans , Male , Maximum Tolerated Dose , Middle Aged , Orchiectomy , Prostatic Neoplasms/epidemiology , Prostatic Neoplasms/surgery , Retrospective Studies , Sarcopenia/epidemiology , Treatment Failure
12.
Transplant Proc ; 42(3): 713-5, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20430154

ABSTRACT

INTRODUCTION: The shortage of organ donors along with the increased number of waiting recipients have created the need for new strategies to expand the organ pool: living donors, split livers, domino livers, and organs from donations after cardiac death (DCD). The purpose of this article was to focus upon aspects of DCD application in the religious, traditional, ethical, and legal aspects of the Arab world. BACKGROUND: DCD can increase the donor pool by 15%-25%. Several ethical, legal, and social concerns need to be addressed to make DCD more widely accepted by the general population in Western countries as well as in the Middle East. Organs from DCD donors have been transplanted since the 1960s. As soon as brain death criteria were published in 1968, organ retrieval from cadaveric heart-beating donors predominated. Donation after brain death (DBD) almost completely replaced DCD. In the 1990s, the organ shortage led to DCD in many countries, but not in the Arab world. DCD is still not accepted by most in the Arab world due to religious, ethical, social, and legal issues. CONCLUSION: DCD in the Arab world is more complicated than in Western countries. It should be re-evaluated and thoroughly reviewed with the new criteria for DCD and its implementation in our region.


Subject(s)
Death, Sudden, Cardiac/epidemiology , Tissue and Organ Procurement/statistics & numerical data , Arabs/psychology , Arabs/statistics & numerical data , Brain Death , Cadaver , Death , Ethics, Medical , Humans , Kidney Transplantation/statistics & numerical data , Legislation, Medical , Middle East/epidemiology , Tissue and Organ Procurement/standards
13.
Nanotechnology ; 20(24): 245704, 2009 Jun 17.
Article in English | MEDLINE | ID: mdl-19471085

ABSTRACT

Internal defects and strain in nanoparticles can influence their properties and therefore measuring these values is relevant. Powder diffraction techniques (neutron and synchrotron) are successfully used to characterize internal strain in the core-shell Ni(3)Si(Al)-SiO(x) nanoparticles having mean diameters of approximately 80 nm. The nanoparticles, which are strain-free after extraction from the bulk alloys, develop internal strain on heating. Both micro- and macro-strains can be measured from the analysis of Bragg peak shift and broadening. It is identified that differences in thermal expansion coefficient of the metallic core and the amorphous shell of the nanoparticles, as well as partial disordering of the L1(2) ordered core phase, are the main causes of strain evolution. Synchrotron measurements also detected partial crystallization of the amorphous silica shell.


Subject(s)
Materials Testing/methods , Nanostructures/chemistry , Nickel/chemistry , Refractometry/methods , Silicon Compounds/chemistry , Silicon Dioxide/chemistry , Elastic Modulus , Stress, Mechanical
14.
Nanotechnology ; 19(6): 065706, 2008 Feb 13.
Article in English | MEDLINE | ID: mdl-21730712

ABSTRACT

There is increasing demand to functionalize meso- and nanoporous materials by coating and make the porous substrate biocompatible or environmentally friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. We adopted the pulsed laser deposition (PLD) method to coat Ni(3)Al-based meso-porous membranes, which were fabricated from a single-crystal Ni-based superalloy by a unique selective phase dissolution technique. These membranes were about 250 µm thick and had channel-like pores (∼200 nm wide) with very high aspect ratio. Two different coating materials, i.e. diamond-like carbon (DLC) and titanium, were used to coat these membranes. High energy C or Ti ions, produced in the plasma plume by the PLD process, penetrated the channel-like pores and deposited coatings on the pore walls deep inside the membrane. The thickness and the quality of coatings on the pore walls were examined using the dual-beam system. The coating thickness, of the order of 50 nm, was adherent to the pore walls and was quite uniform at different depths. The carbon and the Ti deposition behaved quite similarly. The preliminary experiments showed that the PLD is an adequate method for coating fine open cavities of complex geometry. Simulations based on stopping and the range of ions in matter (SRIM) calculations helped in understanding the deposition processes on pore walls at great depths.

15.
Clin Nephrol ; 68(3): 186-9, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17915624

ABSTRACT

Tumor lysis syndrome has historically been associated with hyperuricemia and uric acid crystal deposition. We present three cases of tumor lysis syndrome resulting in renal failure in the context of normouricema, highlighting the spectrum of clinical presentations and mechanisms of renal damage. Two cases occurred following the treatment of hematological malignancies and were associated with hyperphosphatemia; the third resulted from ischemic necrosis following transarterial chemoembolization of a hepatic tumor. We also discuss the role of renal biopsy in the investigation of tumor lysis syndrome.


Subject(s)
Acute Kidney Injury/etiology , Tumor Lysis Syndrome/complications , Acute Kidney Injury/diagnosis , Acute Kidney Injury/therapy , Adult , Carcinoma, Hepatocellular/drug therapy , Humans , Leukemia, Myeloid/drug therapy , Liver Neoplasms/drug therapy , Male , Middle Aged , Tumor Lysis Syndrome/diagnosis , Tumor Lysis Syndrome/therapy
16.
Nanotechnology ; 17(16): 4195-203, 2006 Aug 28.
Article in English | MEDLINE | ID: mdl-21727559

ABSTRACT

We have used an electrochemical selective phase dissolution method to extract nanoprecipitates of the Ni(3)Si-type intermetallic phase from two-phase Ni-Si and Ni-Si-Al alloys by dissolving the matrix phase. The extracted nanoparticles are characterized by transmission electron microscopy, energy-dispersive x-ray spectrometry, x-ray powder diffraction, and electron powder diffraction. It is found that the Ni(3)Si-type nanoparticles have a core-shell structure. The core maintains the size, the shape, and the crystal structure of the precipitates that existed in the bulk alloys, while the shell is an amorphous phase, containing only Si and O (SiO(x)). The shell forms around the precipitates during the extraction process. After annealing the nanoparticles in nitrogen at 700 °C, the tridymite phase recrystallizes within the shell, which remains partially amorphous. In contrast, on annealing in air at 1000 °C, no changes in the composition or the structure of the nanoparticles occur. It is suggested that the shell forms after dealloying of the matrix phase, where Si atoms, the main constituents of the shell, migrate to the surface of the precipitates.

17.
Ann Hum Biol ; 32(4): 407-44, 2005.
Article in English | MEDLINE | ID: mdl-16147394

ABSTRACT

BACKGROUND: Anthropometric variation can be fruitfully utilized to investigate microevolutionary processes. Anthropometric variations in the Indian subcontinent based on stature and three indices (Cephalic Index, Nasal Index, and Total Facial Index) are highly variable and discriminative among populations across geographical regions. AIMS: Anthropometric variation in stature, Cephalic Index (CI), Nasal Index (NI) and Total Facial Index (TFI) were investigated with respect to ethnic, linguistic, geographical and climatic affiliation, across the Indian subcontinent. SUBJECTS AND METHODS: Published data on anthropometric variations of 531 populations from the Indian subcontinent were analysed using discriminant analysis and spatial autocorrelation analysis. RESULTS: Discriminant analysis of the four anthropometric variables shows that stature and NI are good discriminators for populations of different languages. Stature, NI and CI discriminate well among populations of diverse ethnic origin and climatic conditions in different regions. TFI is not a good discriminator for populations of diverse ethnic, linguistic and climatic attributes. Spatial autocorrelation analysis showed significant departure from randomness, suggesting geographic structuring. The Moran's I estimate is positive and statistically significant for the four variables at low distances but exhibits significant negative association at higher values. CONCLUSION: The results suggest geographical clines for the four anthropometric variables and indicate the influence of population structure on the studied variables.


Subject(s)
Anthropometry/methods , Climate , Ethnicity , Language , Analysis of Variance , Chi-Square Distribution , Geography , Humans , India , Time Factors
18.
Nanotechnology ; 16(10): 2176-87, 2005 Oct.
Article in English | MEDLINE | ID: mdl-20817992

ABSTRACT

A method which is able to produce different types of nano-structured materials, namely nano-particles, nano-structured surfaces and nano-porous membranes, from two-phase metallic alloys is reviewed. The new process first establishes nano-structures in the bulk alloy and then separates them by selective phase dissolution. Variation in processing makes it possible to produce different types of nano-structure even from the same alloy. The process can be applied to many different alloy systems. An overview is presented emphasizing the versatility of the process with examples of different nano-structure types that can be produced. Further, the new method is discussed in relation to similar processes (specifically, electrochemical processes) which have been used for nano-structure synthesis.

19.
Indian J Physiol Pharmacol ; 41(3): 269-74, 1997 Jul.
Article in English | MEDLINE | ID: mdl-10232772

ABSTRACT

Effect of felodipine on serum lipids of rabbits was studied and was compared with that of propranolol. Lipid parameters were estimated at basal (0 wk), end of 4th and 16th week of diet/drug administration by using standard kits for analysis. There was a significant increase in mean serum cholesterol, TG, VLDLc, LDLC and decrease in HDLc, (P<0.05) in the group of rabbits receiving Atherogenic diet (AD)/Propranolol. This effect was maximally observed in rabbits receiving both AD and propranolol. This change was satisfactorily prevented when felodipine was administered from very beginning (P<0.001). In addition, there was a significant increase in HDLc (28.89%) of rabbits receiving felodipine from beginning. Thus both AD and propranolol have dyslipidemic effect and early administration of felodipine favorably changes all lipid parameters.


Subject(s)
Calcium Channel Blockers/pharmacology , Felodipine/pharmacology , Hypolipidemic Agents/pharmacology , Lipids/blood , Propranolol/pharmacology , Animals , Antihypertensive Agents/pharmacology , Lipids/chemistry , Male , Rabbits
20.
Man India ; 68(2-3): 252-7, 1988.
Article in English | MEDLINE | ID: mdl-12342056

ABSTRACT

"There is an assumption that family planning leads to less infant mortality, and [that a] lower rate of infant mortality will lead toward the evolution of small family. The present paper, based on the data collected from 472 eligible couples from a suburban area of West Bengal, does not reveal any such strong relation between family planning and infant mortality. The data have also been examined in the perspective of familial economic status and formal educational standard of the mothers concerned."


Subject(s)
Educational Status , Family Planning Services , Infant Mortality , Social Class , Asia , Demography , Developing Countries , Economics , India , Mortality , Population , Population Dynamics , Socioeconomic Factors
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