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Malherbe F, Roodt L, Noor F, Gamieldien R, Chetty D, Anderson D, Thebe T, Cairncross L. Magseed placement before neoadjuvant chemotherapy to facilitate subsequent breastconserving surgery - a single-centre audit. S AFR J SURG 2022; 60:109-114. [PMID: 35851364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
BACKGROUND A radio-opaque clip is placed in all patients planned for breast-conserving surgery (BCS) receiving neoadjuvant chemotherapy (NACT) to localise the tumour bed in case response to chemotherapy makes later localisation impossible. A tumour that was localised with a radio-opaque clip before NACT will then need a second localisation procedure, after the completion of NACT to aid BCS. The two most commonly used methods are hookwire and radioguided occult lesion localisation. Magseed®, a newly available technology consisting of a small magnetic seed, has now become available. The seed is placed instead of a radio-opaque clip before the start of or during NACT and can remain in place until the time of BCS. METHODS A retrospective cohort study was performed, collecting data on patients who had a Magseed placed before or during NACT from December 2018 to February 2020. RESULTS Twenty-one Magseed devices were placed into the breasts of 20 patients, 18 under ultrasound guidance, and three under stereotactic guidance. The average breast volume of individuals who had seeds placed was 1 532 g ± 869 g. The duration that the seeds were in situ was 138 days ± 45 days. All preoperatively placed seeds were retrieved at the surgery with no observed migration outside the tumour bed. CONCLUSION Magseed placement before NACT is a safe and technically simple technique that can be done under ultrasound guidance in the majority of cases. It has the advantage of being a single procedure with an associated reduction in time off work and travel cost to the patient, as well as flexibility in terms of the time of placement.
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Affiliation(s)
- F Malherbe
- Division of General Surgery, University of Cape Town, South Africa
| | - L Roodt
- Division of General Surgery, University of Cape Town, South Africa
| | - F Noor
- Division of General Surgery, University of Cape Town, South Africa
| | - R Gamieldien
- Division of Radiology, University of Cape Town, South Africa
| | - D Chetty
- Division of Anatomical Pathology, University of Cape Town, South Africa
| | - D Anderson
- Division of Radiation Oncology, University of Cape Town, South Africa
| | - T Thebe
- Division of Radiation Oncology, University of Cape Town, South Africa
| | - L Cairncross
- Division of General Surgery, University of Cape Town, South Africa
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Chetty D, Glover RD, Tong XM, deHarak BA, Xu H, Haram N, Bartschat K, Palmer AJ, Luiten AN, Light PS, Litvinyuk IV, Sang RT. Carrier-Envelope Phase-Dependent Strong-Field Excitation. Phys Rev Lett 2022; 128:173201. [PMID: 35570453 DOI: 10.1103/physrevlett.128.173201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 03/15/2022] [Indexed: 06/15/2023]
Abstract
We present a joint experimental-theoretical study on the effect of the carrier-envelope phase (CEP) of a few-cycle pulse on the atomic excitation process. We focus on the excitation rates of argon at intensities in the transition between the multiphoton and tunneling regimes. Through numerical simulations, we show that the resulting bound-state population is highly sensitive to both the intensity and the CEP. The experimental data clearly agree with the theoretical prediction, and the results encourage the use of precisely tailored laser fields to coherently control the strong-field excitation process. We find a markedly different behavior for the CEP-dependent bound-state population at low and high intensities with a clear boundary, which we attribute to the transition from the multiphoton to the tunneling regime.
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Affiliation(s)
- D Chetty
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - R D Glover
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
- Institute for Photonics and Advanced Sensing and School of Physical Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - X M Tong
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan
| | - B A deHarak
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
- Physics Department, Illinois Wesleyan University, Bloomington, Illinois 61702-2900, USA
| | - H Xu
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - N Haram
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - K Bartschat
- Department of Physics and Astronomy, Drake University, Des Moines, Iowa 50311, USA
| | - A J Palmer
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - A N Luiten
- Institute for Photonics and Advanced Sensing and School of Physical Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - P S Light
- Institute for Photonics and Advanced Sensing and School of Physical Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - I V Litvinyuk
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - R T Sang
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
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Malherbe F, Roodt L, Noor F, Gamieldien R, Chetty D, Anderson D, Thebe T, Cairncross L. Magseed placement before neoadjuvant chemotherapy to facilitate subsequent breast-conserving surgery – a single-centre audit. S AFR J SURG 2022. [DOI: 10.17159/2078-5151/sajs3679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND: A radio-opaque clip is placed in all patients planned for breast-conserving surgery (BCS) receiving neoadjuvant chemotherapy (NACT) to localise the tumour bed in case response to chemotherapy makes later localisation impossible. A tumour that was localised with a radio-opaque clip before NACT will then need a second localisation procedure, after the completion of NACT to aid BCS. The two most commonly used methods are hookwire and radio-guided occult lesion localisation. Magseed®, a newly available technology consisting of a small magnetic seed, has now become available. The seed is placed instead of a radio-opaque clip before the start of or during NACT and can remain in place until the time of BCS. METHODS: A retrospective cohort study was performed, collecting data on patients who had a Magseed placed before or during NACT from December 2018 to February 2020. RESULTS: Twenty-one Magseed devices were placed into the breasts of 20 patients, 18 under ultrasound guidance, and three under stereotactic guidance. The average breast volume of individuals who had seeds placed was 1 532 g ± 869 g. The duration that the seeds were in situ was 138 days ± 45 days. All preoperatively placed seeds were retrieved at the surgery with no observed migration outside the tumour bed. CONCLUSION: Magseed placement before NACT is a safe and technically simple technique that can be done under ultrasound guidance in the majority of cases. It has the advantage of being a single procedure with an associated reduction in time off work and travel cost to the patient, as well as flexibility in terms of the time of placement.
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Antel K, Chetty D, Oosthuizen J, Mohamed Z, Van der Vyver L, Verburgh E. CD68-positive tumour associated macrophages, PD-L1 expression, and EBV latent infection in a high HIV-prevalent South African cohort of Hodgkin lymphoma patients. Pathology 2021; 53:628-634. [PMID: 33558066 DOI: 10.1016/j.pathol.2020.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/30/2020] [Accepted: 11/02/2020] [Indexed: 10/22/2022]
Abstract
A higher proportion of CD68-positive tumour associated macrophages (TAMs) has been associated with poorer outcomes in HIV-negative patients with Hodgkin lymphoma (HL), but whether this is true in HIV-positive patients with HL is not known. In this study, we investigated the number of CD68-positive TAMs and expression of programmed cell death-ligand 1 (PD-L1) in lymph node specimens from HL patients and correlated expression with clinical features (HIV status, disease severity and survival) and histopathological features (EBV latent positivity and subtype of HL). We stained archived lymph node specimens from 77 patients diagnosed with HL for CD68 and PD-L1. Stains were graded as: CD68 low (≤25%), CD68 high (>25%), PD-L1 low (≤50%), and PD-L1 high (>50%). Expression levels were correlated with the clinical and histopathological features using bivariate and multivariate analyses. Survival was analysed by overall and progression-free survival. Thirty-four of the 77 included patients (44%) were HIV-positive. EBV latency was detected in 97% of HIV-positive HL patients and in 14% of HIV-negative HL patients. A high CD68 score was associated with lower median haemoglobin levels (9.4 vs 11.4 g/dL; p=0.02), platelet numbers (262 vs 424 cells ×109/L; p=0.01), and lymphocyte numbers (0.99 vs 1.70 cells ×109/L, p=0.01) and a trend towards advanced disease (international prognostic score ≥4; hazard ratio 2.4; confidence interval 0.89-6.47; p=0.08). HIV status did not affect CD68 or PD-L1 expression. A higher proportion of CD68-positive TAMs was found in samples that were EBV-positive. HIV positivity and EBV negativity correlated with poorer survival. CD68 and PD-L1 expression were not predictive of survival. High CD68 expression was associated with EBV positivity but not HIV positivity and did not predict adverse outcomes. PD-L1 expression was unaffected by HIV status or EBV positivity and did predict adverse outcomes.
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Affiliation(s)
- Katherine Antel
- Division of Clinical Haematology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa.
| | - D Chetty
- Division of Anatomical Pathology, Department of Pathology, Faculty of Health Sciences, University of Cape Town and National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa
| | - J Oosthuizen
- Division of Clinical Haematology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - Z Mohamed
- Department of Radiation Oncology, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - L Van der Vyver
- Division of Clinical Haematology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | - E Verburgh
- Division of Clinical Haematology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
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Haram N, Ivanov I, Xu H, Kim KT, Atia-Tul-Noor A, Sainadh US, Glover RD, Chetty D, Litvinyuk IV, Sang RT. Relativistic Nondipole Effects in Strong-Field Atomic Ionization at Moderate Intensities. Phys Rev Lett 2019; 123:093201. [PMID: 31524440 DOI: 10.1103/physrevlett.123.093201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Indexed: 06/10/2023]
Abstract
We present a detailed experimental and theoretical study on the relativistic nondipole effects in strong-field atomic ionization by near-infrared linearly polarized few-cycle laser pulses in the intensity range of 10^{14}-10^{15} W/cm^{2}. We record high-resolution photoelectron momentum distributions of argon using a reaction microscope and compare our measurements with a truly ab initio fully relativistic 3D model based on the time-dependent Dirac equation. We observe counterintuitive peak shifts of the transverse electron momentum distribution in the direction opposite to that of laser propagation as a function of laser intensity and demonstrate an excellent agreement between the experimental results and theoretical predictions.
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Affiliation(s)
- Nida Haram
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - Igor Ivanov
- Centre for Relativistic Laser Science, Institute for Basic Science, Gwangju, 61005, Republic of Korea
| | - Han Xu
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - Kyung Taec Kim
- Centre for Relativistic Laser Science, Institute for Basic Science, Gwangju, 61005, Republic of Korea
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - A Atia-Tul-Noor
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - U Satya Sainadh
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - R D Glover
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - D Chetty
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - I V Litvinyuk
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
| | - R T Sang
- Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
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Smijesh N, Rao KH, Chetty D, Litvinyuk IV, Sang RT. Plasma plumes produced by laser ablation of Al with single and double pulse schemes. Opt Lett 2018; 43:6081-6084. [PMID: 30548009 DOI: 10.1364/ol.43.006081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 11/12/2018] [Indexed: 06/09/2023]
Abstract
We generated and characterized plasma with single and double picosecond laser pulses to study the plume dynamics and to control the plasma properties. The double pulse scheme was found to be superior for generating a homogeneous plasma. Lateral expansion was prominent in irradiation schemes wherein the energy in the first pulse is lower than or equal to that of the second pulse. The velocities of the fast and slow species were found to be nearly equal with the emission counts corresponding to slow species being larger for the single pulse compared to the double pulse.
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Chetty D, Hoque ME. Effectiveness of a nurse facilitated cognitive group intervention among mild to moderately-depressed-women in KwaZulu-Natal, South Africa. ACTA ACUST UNITED AC 2013; 16:29-34. [PMID: 23417633 DOI: 10.4314/ajpsy.v16i1.5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Accepted: 11/04/2011] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The purpose of the study was to determine the effectiveness of a nurse-facilitated-cognitive-group (NFCG) intervention as an adjunct to antidepressant medication, in mild to moderately, depressed women. METHOD This was a quasi-experimental, nonequivalent, control group design study. A sample of 30 consenting participants was selected from an urban, community psychiatric clinic, and the participants were randomly allocated to the control and the intervention groups. The effectiveness of the intervention was measured using the Beck Depression Inventory (BDI). RESULTS After six weeks of implementation of the NFCG intervention, there was a decrease in the BDI scores of the intervention group, and an increase in the BDI scores in the control group (CG) - but the difference in scores was not significant (Student's t-test=1.076, p=0.291). After 12 weeks of the group intervention, the BDI scores for the intervention group, showed a considerable reduction in their levels of depression, whilst the participants of the control group had a further increase in their scores. There was a statistically significant difference between the groups, with respect to the BDI scores (p<0.001). The Friedman test indicated that the mean BDI scores, were statistically significant (p<0.001) within the intervention group, meaning that the BDI scores improved, at the end of the intervention for all the participants. Analysis of the BDI scores, using the Friedman test, showed that there was no improvement in the control group (p=0.597). CONCLUSION The NFCG intervention, as an adjunct to antidepressant medication, contributed to a reduction in depressive symptoms.
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Affiliation(s)
- D Chetty
- Department of Nursing Science, School of Health Care Sciences, University of Limpopo (Medunsa Campus), South Africa
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Shamra V, Donde B, Mohiuddin M, Rabin B, Majeed U, Chetty D, Nyongensa C, Msemo A, Van der Merwe D, Glynn-Thomas R. Vertebral height as the measure of lesion length in carcinoma of the oesophagus - is it accurate? SA J Radiol 2004. [DOI: 10.4102/sajr.v8i1.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
No abstract available.
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