Publications by authors named "Arvind K Sharma"

31 Publications

Association of SARS CoV-2 Cycle Threshold (Ct) with Outcomes in COVID-19: Hospital-Based Study.

J Assoc Physicians India 2021 07;69(7):20-23

Academic Research Development Unit, Rajasthan University of Health Sciences, Jaipur, Rajasthan.

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July 2021

The mucormycosis epidemic within COVID-19 pandemic- lessons from India.

Brain Behav Immun 2021 Aug 8. Epub 2021 Aug 8.

Department of Medicine, National University Hospital and Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Electronic address:

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http://dx.doi.org/10.1016/j.bbi.2021.08.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8349392PMC
August 2021

Efficacy of IVRS-based mHealth intervention in reducing cardiovascular risk in metabolic syndrome: A cluster randomized trial.

Diabetes Metab Syndr 2021 Jun 21;15(5):102182. Epub 2021 Jun 21.

Academic Research Development Unit, Rajasthan University of Health Sciences, 302033, Jaipur, India.

Aims: Efficacy of mobile-phone based intervention for reducing cardiovascular risk in metabolic syndrome (MetSyn).

Methods: We screened adults 20-60 years in 10 villages in India for MetSyn using stratified cluster sampling. Lifestyle and biochemical risk factors were assessed. International Harmonized Criteria were used for diagnosis. Villages were randomized with 5 each in control and intervention groups. Interactive voice response system (IVRS) in Hindi was developed. In intervention clusters two messages for promotion of healthy lifestyle and medical treatment were broadcast daily over 12-months and risk factors reassessed.

Results: 1012/1200(84%) persons were screened and MetSyn diagnosed in 286(28.3%). Villages were divided into 5 control(n = 136) and 5 intervention(n = 147) clusters. Baseline characteristics in both clusters were similar. Acceptability of intervention was >60% in 80% participants. At 12 months, significantly greater participants in intervention vs control clusters had healthier lifestyle (healthy diet 28.8vs14.7%, physical activity 25.9vs13.1%, tobacco 13.7vs32.5%), anthropometry (waist circumference 85.7 ± 6.3vs88.6 ± 14.0 cm, body mass index 21.9 ± 2.8vs23.1 ± 2.9 kg/m), systolic BP 123.6 ± 7.7vs128.6 ± 14.1 mmHg, fasting glucose 95.6 ± 19.4vs109.4 ± 43.7 mg/dl, cholesterol 175.5 ± 36.5vs186.4 ± 43.3 mg/dl, and triglycerides 147.6 ± 48.3vs159.5 ± 60.7 mg/dl (p < 0.01). Prevalence of metabolic syndrome declined in intervention group by 22.3%vs3.9%, p < 0.001).

Conclusion: An interactive voice response system based technology significantly reduced multiple cardiovascular risk factors and prevalence of metabolic syndrome.
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http://dx.doi.org/10.1016/j.dsx.2021.06.019DOI Listing
June 2021

Mucormycosis and COVID-19: An epidemic within a pandemic in India.

Mycoses 2021 Jul 13. Epub 2021 Jul 13.

Division of Neurology, Department of Medicine, National University Hospital and Yong Loo Lin School of Medicine, National University of Singapore, Singapore.

Importance: Coronavirus disease (COVID-19) causes an immunosuppressed state and increases risk of secondary infections like mucormycosis. We evaluated clinical features, predisposing factors, diagnosis and outcomes for mucormycosis among patients with COVID-19 infection.

Methods: This prospective, observational, multi-centre study included 47 consecutive patients with mucormycosis, diagnosed during their course of COVID-19 illness, between January 3 and March 27, 2021. Data regarding demography, underlying medical conditions, COVID-19 illness and treatment were collected. Clinical presentations of mucormycosis, imaging and biochemical characteristics and outcome were recorded.

Results: Of the 2567 COVID-19 patients admitted to 3 tertiary centres, 47 (1.8%) were diagnosed with mucormycosis. Mean age was 55 ± 12.8years, and majority suffered from diabetes mellitus (n = 36, 76.6%). Most were not COVID-19 vaccinated (n = 31, 66.0%) and majority (n = 43, 91.5%) had developed moderate-to-severe pneumonia, while 20 (42.6%) required invasive ventilation. All patients had received corticosteroids and broad-spectrum antibiotics while most (n = 37, 78.7%) received at least one anti-viral medication. Mean time elapsed from COVID-19 diagnosis to mucormycosis was 12.1 ± 4.6days. Eleven (23.4%) subjects succumbed to their disease, mostly (n = 8, 72.7%) within 7 days of diagnosis. Among the patients who died, 10 (90.9%) had pre-existing diabetes mellitus, only 2 (18.2%) had received just one vaccine dose and all developed moderate-to-severe pneumonia, requiring oxygen supplementation and mechanical ventilation.

Conclusions: Mucormycosis can occur among COVID-19 patients, especially with poor glycaemic control, widespread and injudicious use of corticosteroids and broad-spectrum antibiotics, and invasive ventilation. Owing to the high mortality, high index of suspicion is required to ensure timely diagnosis and appropriate treatment in high-risk populations.
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http://dx.doi.org/10.1111/myc.13353DOI Listing
July 2021

Mucormycosis- A Dreaded Complication Of Covid-19.

QJM 2021 Jun 14. Epub 2021 Jun 14.

Yong Loo Lin School of Medicine, National University of Singapore and Division of Neurology, National University Hospital, Singapore.

Covid-19 pandemic is in a massive second wave in India. The new variant is considered more infectious. Diabetic patients are considered more vulnerable to develop some of the complications of acute Covid-19 infections. Furthermore, steroids are being used in the treatment of Covid-19 related pneumonia in a large number of patients. Hence, secondary fungal infections are being increasing observed, with very high mortality. We present the clinical, imaging and histopathological features in a diabetic patient who recovered from acute Covid-19 infection. However, he developed palatal and maxillary mucormycosis. Mucosal debridement, sinus surgery and antifungal treatment led to a satisfactory outcome.
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http://dx.doi.org/10.1093/qjmed/hcab166DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8344851PMC
June 2021

An Asia-Pacific study on healthcare workers' perceptions of, and willingness to receive, the COVID-19 vaccination.

Int J Infect Dis 2021 May 26;106:52-60. Epub 2021 Mar 26.

Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Division of Neurology, Department of Medicine, National University Health System, Singapore.

Objective: In the fight against COVID-19, vaccination is vital in achieving herd immunity. Many Asian countries are starting to vaccinate frontline workers; however, expedited vaccine development has led to hesitancy among the general population. We evaluated the willingness of healthcare workers to receive the COVID-19 vaccine.

Methods: From 12 to 21 December 2020, we recruited 1720 healthcare workers from 6 countries: China, India, Indonesia, Singapore, Vietnam and Bhutan. The self-administrated survey collected information on willingness to vaccinate, perception of COVID-19, vaccine concerns, COVID-19 risk profile, stigma, pro-socialness scale, and trust in health authorities.

Results: More than 95% of the healthcare workers surveyed were willing to vaccinate. These respondents were more likely to perceive the pandemic as severe, consider the vaccine safe, have less financial concerns, less stigmatization regarding the vaccine, higher pro-socialness mindset and trust in health authorities. A high perceived pandemic risk index, low vaccine harm index and high pro-socialness index were independent predictors in multivariable analysis.

Conclusions: The majority of healthcare workers in Asia are willing to receive COVID-19 vaccination. Perceived COVID-19 susceptibility, low potential risk of vaccine harm and pro-socialness are the main drivers. These findings may help formulate vaccination strategies in other countries.
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http://dx.doi.org/10.1016/j.ijid.2021.03.069DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7997703PMC
May 2021

Macrolevel association of COVID-19 with non-communicable disease risk factors in India.

Diabetes Metab Syndr 2021 Jan-Feb;15(1):343-350. Epub 2021 Jan 20.

Department of Medicine and Critical Care, Eternal Hospital, Eternal Heart Care Centre & Research Institute, Jaipur, India; Academic Research Development Unit, Rajasthan University of Health Sciences, Jaipur, India. Electronic address:

Background & Aims: Greater COVID-19 related mortality has been reported among persons with various non-communicable diseases (NCDs). We performed an ecological study to determine the association of state-level cases and deaths with NCD risk factors and healthcare and social indices.

Methods: We obtained cumulative national and state-level data on COVID-19 cases and deaths from publicly available database www.covid19india.org from February to end November 2020. To identify association with major NCD risk factors, NCDs, healthcare related and social variables we obtained data from public sources. Association was determined using univariate and multivariate statistics.

Results: More than 9.5 million COVID-19 cases and 135,000 deaths have been reported in India towards end of November 2020. There is significant positive correlation (Pearson r) of state-level COVID-19 cases and deaths per million, respectively, with NCD risk factors- obesity (0.64, 0.52), hypertension (0.28, 0.16), diabetes (0.66, 0.46), NCD epidemiological transition index (0.58, 0.54) and ischemic heart disease mortality (0.22, 0.33). Correlation is also observed with indices of healthcare access and quality (0.71, 0.61), urbanization (0.75, 0.73) and human (0.61, 0.56) and sociodemographic (0.70, 0.69) development. Multivariate adjusted analyses shows strong correlation of COVID-19 burden and deaths with NCD risk factors (r = 0.51, 0.43), NCDs (r = 0.32, 0.16) and healthcare (r = 0.52, 0.38).

Conclusions: COVID-19 disease burden and mortality in India is ecologically associated with greater state-level burden of NCDs and risk factors, especially obesity and diabetes.
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http://dx.doi.org/10.1016/j.dsx.2021.01.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7817457PMC
March 2021

Asian-Pacific perspective on the psychological well-being of healthcare workers during the evolution of the COVID-19 pandemic.

BJPsych Open 2020 Oct 8;6(6):e116. Epub 2020 Oct 8.

Division of Neurology, Department of Medicine, National University Health System, Singapore; and Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.

Background: The coronavirus disease 2019 (COVID-19) pandemic has led to significant strain on front-line healthcare workers.

Aims: In this multicentre study, we compared the psychological outcomes during the COVID-19 pandemic in various countries in the Asia-Pacific region and identified factors associated with adverse psychological outcomes.

Method: From 29 April to 4 June 2020, the study recruited healthcare workers from major healthcare institutions in five countries in the Asia-Pacific region. A self-administrated survey that collected information on prior medical conditions, presence of symptoms, and scores on the Depression Anxiety Stress Scales and the Impact of Events Scale-Revised were used. The prevalence of depression, anxiety, stress and post-traumatic stress disorder (PTSD) relating to COVID-19 was compared, and multivariable logistic regression identified independent factors associated with adverse psychological outcomes within each country.

Results: A total of 1146 participants from India, Indonesia, Singapore, Malaysia and Vietnam were studied. Despite having the lowest volume of cases, Vietnam displayed the highest prevalence of PTSD. In contrast, Singapore reported the highest case volume, but had a lower prevalence of depression and anxiety. In the multivariable analysis, we found that non-medically trained personnel, the presence of physical symptoms and presence of prior medical conditions were independent predictors across the participating countries.

Conclusions: This study highlights that the varied prevalence of psychological adversity among healthcare workers is independent of the burden of COVID-19 cases within each country. Early psychological interventions may be beneficial for the vulnerable groups of healthcare workers with presence of physical symptoms, prior medical conditions and those who are not medically trained.
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http://dx.doi.org/10.1192/bjo.2020.98DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7542327PMC
October 2020

Effect of erroneous body-weight estimation on outcome of thrombolyzed stroke patients.

J Thromb Thrombolysis 2020 Nov;50(4):921-928

Division of Neurology, National University Health System, Singapore, Singapore.

Intravenously administered tissue plasminogen activator (IV-tPA), dose determined by patients' body-weight, remains the only approved drug treatment for acute ischemic stroke (AIS). Since a shorter onset-to-treatment time results in better functional outcome, treatment is often initiated according to the estimated or last-known body-weight of the patient. This approach may result in underdosing or overdosing of tPA. In this multicenter retrospective study, we evaluated the extent of error in tPA dosing in our AIS cohort and its impact on functional outcome and symptomatic intracranial hemorrhage (SICH). Consecutive AIS patients, receiving IV-tPA, dose determined by the estimated body-weight, at three tertiary centers between January and December 2017 were included. Collected data included information about demographics, cardiovascular risk factors, stroke subtype and National Institute of Health Stroke Scale (NIHSS) score. Estimated and measured body-weights were recorded. Modified Rankin scale (mRS) of 2 or more defined unfavorable outcome. The study included 150 patients. Median age was 64 -years (IQR 55-75) with male preponderance (67%) and median NIHSS score of 9 points (IQR 6-17). Mean measured weight of our study population was 58 (SD 13) kg. Median difference between actual and estimated body-weight was 3 kg (IQR 1.5-6). Difference was more than 10% in 35 (23.3%) patients. Good functional outcome (mRS 0-1) was achieved by 74 (49.3%) patients and 10 (6.8%) developed SICH. NIHSS (OR 1.288; 95% CI 1.157-1.435, p < 0.001) and large artery atherosclerosis (OR 5.878; 95% CI 1.929-17.910, p = 0.002) were independent predictors of unfavorable functional outcome. Our finding of the statistically insignificant 2.5-fold increase in poor outcomes among patients where the estimated and actual weight differed by more than 10% should be interpreted with caution due to the limited sample size. Significant difference occurs between estimated and actual body-weight in a considerable proportion of thrombolysed AIS patients. However, this discrepancy does not affect functional outcome or the risk of SICH.
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http://dx.doi.org/10.1007/s11239-020-02118-3DOI Listing
November 2020

A multinational, multicentre study on the psychological outcomes and associated physical symptoms amongst healthcare workers during COVID-19 outbreak.

Brain Behav Immun 2020 08 21;88:559-565. Epub 2020 Apr 21.

Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Division of Neurology, Department of Medicine, National University Health System, Singapore. Electronic address:

Objective: Since the declaration of the coronavirus 2019 (COVID-19) outbreak as pandemic, there are reports on the increased prevalence of physical symptoms observed in the general population. We investigated the association between psychological outcomes and physical symptoms among healthcare workers.

Methods: Healthcare workers from 5 major hospitals, involved in the care for COVID-19 patients, in Singapore and India were invited to participate in a study by performing a self-administered questionnaire within the period of February 19 to April 17, 2020. Healthcare workers included doctors, nurses, allied healthcare workers, administrators, clerical staff and maintenance workers. This questionnaire collected information on demographics, medical history, symptom prevalence in the past month, Depression Anxiety Stress Scales (DASS-21) and the Impact of Events Scale-Revised (IES-R) instrument. The prevalence of physical symptoms displayed by healthcare workers and the associations between physical symptoms and psychological outcomes of depression, anxiety, stress, and post-traumatic stress disorder (PTSD) were evaluated.

Results: Out of the 906 healthcare workers who participated in the survey, 48 (5.3%) screened positive for moderate to very-severe depression, 79 (8.7%) for moderate to extremely-severe anxiety, 20 (2.2%) for moderate to extremely-severe stress, and 34 (3.8%) for moderate to severe levels of psychological distress. The commonest reported symptom was headache (32.3%), with a large number of participants (33.4%) reporting more than four symptoms. Participants who had experienced symptoms in the preceding month were more likely to be older, have pre-existing comorbidities and a positive screen for depression, anxiety, stress, and PTSD. After adjusting for age, gender and comorbidities, it was found that depression (OR 2.79, 95% CI 1.54-5.07, p = 0.001), anxiety (OR 2.18, 95% CI 1.36-3.48, p = 0.001), stress (OR 3.06, 95% CI 1.27-7.41, p = 0.13), and PTSD (OR 2.20, 95% CI 1.12-4.35, p = 0.023) remained significantly associated with the presence of physical symptoms experienced in the preceding month. Linear regression revealed that the presence of physical symptoms was associated with higher mean scores in the IES-R, DASS Anxiety, Stress and Depression subscales.

Conclusions: Our study demonstrates a significant association between the prevalence of physical symptoms and psychological outcomes among healthcare workers during the COVID-19 outbreak. We postulate that this association may be bi-directional, and that timely psychological interventions for healthcare workers with physical symptoms should be considered once an infection has been excluded.
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http://dx.doi.org/10.1016/j.bbi.2020.04.049DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7172854PMC
August 2020

Transcranial Doppler: Techniques and advanced applications: Part 2.

Ann Indian Acad Neurol 2016 Jan-Mar;19(1):102-7

Department of Neurology, National University Hospital and YLL School of Medicine, National University of Singapore, Singapore.

Transcranial Doppler (TCD) is the only diagnostic tool that can provide continuous information about cerebral hemodynamics in real time and over extended periods. In the previous paper (Part 1), we have already presented the basic ultrasound physics pertaining to TCD, insonation methods, and various flow patterns. This article describes various advanced applications of TCD such as detection of right-to-left shunt, emboli monitoring, vasomotor reactivity (VMR), monitoring of vasospasm in subarachnoid hemorrhage (SAH), monitoring of intracranial pressure, its role in stoke prevention in sickle cell disease, and as a supplementary test for confirmation of brain death.
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http://dx.doi.org/10.4103/0972-2327.173407DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4782524PMC
March 2016

Nanostructuring with chirality: binaphthyl-based synthons for the production of functional oriented nanomaterials.

Nanoscale 2014 Jul;6(13):7165-74

Department of Chemistry, University of Pavia, Viale Taramelli 10, 27100 Pavia, Italy.

Chirality is a powerful tool for the generation of order, directionality, and, as such, of function, in assembled nanoscale chemical devices. Axially chiral binaphthyls have been widely used in organic synthesis; the stability of the enantiomers enables their use as robust chirality inducers and catalysts in asymmetric reactions, and they are nowadays industrially applied in a variety of organic transformations. Applications of these compounds in the field of nanosciences are more recent, and not yet fully explored. The integration of such a robust class of chiral compounds, capable of efficient transfer of stereochemical information, into functional aggregates and nanoarchitectures is of great current interest. We will discuss preeminent examples of applications of these synthons in several fields of nanoscience, such as reticular chemistry, non-linear optical materials and imaging, and liquid crystals.
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http://dx.doi.org/10.1039/c4nr00801dDOI Listing
July 2014

Usefulness of transcranial Doppler-derived cerebral hemodynamic parameters in the noninvasive assessment of intracranial pressure.

J Neuroimaging 2015 Jan-Feb;25(1):111-6. Epub 2014 Mar 5.

Division of Neurology, National University Health System, Singapore.

Background: Transcranial Doppler (TCD) ultrasonography is a noninvasive bedside tool that can evaluate cerebral blood flow hemodynamics in major intracranial arteries. TCD-derived pulsatility index (PI) is believed to be influenced by intracranial pressure (ICP).

Objective: To correlate TCD-PI with cerebrospinal fluid (CSF) pressure (representing ICP), measured by standard lumbar puncture (LP) manometry.

Methods: CSF pressures (CSF-P) were measured in 78 patients by LP manometry. Stable TCD spectra were obtained 5 minutes before LP from either middle cerebral arteries using Spencer's head frame and 2-MHz transducer. PI values were calculated from the TCD spectra by an independent neurosonologist.

Results: Factors displaying a significant relationship with CSF-P included age (R = -.426, P < .0005); EDV (R = -.328, P = .002;) and PI (R = .650, P < .0005). On analyzing dichotomized data (CSF-P < 20 vs. ≥ 20 cm H2 0) TCD-PI was an independent determinant (OR per .1 increase in PI = 2.437; 95% CI, 1.573-3.777; P < .0005). PI ≥ 1.26 could reliably predict CSF-P ≥ 20 cm H2 0 (sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were 81.1%, 96.3%, 93.8%, 88.1%, and 90.1% respectively).

Conclusion: TCD-derived PI could be used to identify patients with CSF-P ≥ 20 cm H2 0 and may play an important role as a monitoring tool.
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http://dx.doi.org/10.1111/jon.12100DOI Listing
September 2015

Cerebral hyperperfusion syndrome after superficial temporal artery-middle cerebral artery bypass for severe intracranial steno-occlusive disease: a case control study.

Neurosurgery 2013 Jun;72(6):936-42; discussion 942-3

Division of Neurosurgery, National University Hospital, Singapore.

Background: Intracranial stenoses carry increased risk for cerebral ischemia. We perform external carotid-internal carotid (EC-IC) artery bypass in our patients with severe stenosis of the intracranial internal carotid (ICA) or middle cerebral artery (MCA) with impaired cerebral vasodilatory reserve (CVR).

Objective: To evaluate cerebral hemodynamics and cerebral hyperperfusion syndrome (HPS) in patients who develop focal neurological deficits after EC-IC bypass surgery.

Methods: Patients with severe intracranial ICA or MCA stenosis and impaired CVR on transcranial Doppler (TCD) derived breath-holding index (BHI) were evaluated with acetazolamide-challenged technetium-99m hexamethylpropyleneamineoxime-single-photon emission computed tomography (SPECT). EC-IC bypass surgery was offered to patients with impaired CVR on SPECT. Close monitoring was performed in patients developing focal neurological deficits within 7 days of surgery.

Results: Of 112 patients with severe intracranial ICA/MCA stenosis, 77 (69%) showed impaired CVR and 46 (41%) underwent EC-IC bypass. Transient neurological deficits within 7 days of surgery developed in 8 (17%). HPS was confirmed by CT perfusion and/or SPECT in 7 cases. A strong correlation was observed between HPS and preoperative TCD-BHI values (0%, 6.3%, and 41% in patients with BHI 0.3-0.69, 0-0.3 and <0, respectively; P = .012). HPS patients showed more than a 50% increase in MCA flow velocity on TCD (compared with preoperative values) on the operated side (63.3% vs 3.3% on control side, P < .001). Meticulous control of blood pressure and hydration led to rapid and complete resolution of neurological deficits in all cases.

Conclusion: Symptomatic cerebral HPS is common in the early postoperative period after EC-IC bypass surgery. Early diagnosis and appropriate management might prevent the complications of this syndrome.
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http://dx.doi.org/10.1227/NEU.0b013e31828bb8b3DOI Listing
June 2013

Switching of emissive and NLO properties in push-pull chromophores with crescent PPV-like structures.

Phys Chem Chem Phys 2013 Feb 17;15(5):1666-74. Epub 2012 Dec 17.

Department of Chemistry, University of Pavia, Viale Taramelli, 10-27100 Pavia, Italy.

We report on a series of novel homologous push-pull compounds, in which identical donor (a dimethylamino) and acceptor (a malonate ester) functionalities endcap crescent PPV fragments, bearing, respectively, 1, 2 and 3 p-phenylenevinylene units in direct linear conjugation (compounds 7-9). The three compounds exhibit striking differences in their linear and nonlinear optical properties. The shorter compound 7 exhibits aggregation-induced emission with a strong luminescence in the solid state (blue emission, photoluminescence quantum yield 38%), and it is nonemissive in solution; the more extended conjugated systems 8 and 9 show classical aggregation-caused quenching in the solid state, while high quantum yield photoluminescence (21 and 93% in toluene) is restored in diluted solutions, through mechanisms involving intramolecular charge transfer in the excited states. EFISH measurements in solutions demonstrate a strong solvent and concentration dependence. As rationalized with the aid of molecular modelling, compounds 8 and, more markedly, 9 aggregate in stable centrosymmetric dimers in solution.
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http://dx.doi.org/10.1039/c2cp43140hDOI Listing
February 2013

Spectroscopic and electrochemical sensing of lanthanides with π-extended chromophores incorporating ferrocenes and a coordinative end.

Dalton Trans 2011 Nov 4;40(44):11719-25. Epub 2011 Oct 4.

Department of Chemistry, University of Pavia, Italy.

In this study, we report the synthesis and characterization of three novel "push-pull" chromophores, in which multiple phenylenevinylene units are endcapped by ferrocene as donor units and malonate moieties as acceptor units. These chromophores have spectroscopic and electrochemical characteristics which consistently change according to the extension of the conjugated bridge, thus to the variation of the HOMO-LUMO band gap. The 1,3-dicarbonyl units, directly incorporated into the conjugated molecular structures, are able to coordinate Lewis acid-like cations, such as lanthanides, as confirmed by UV/Vis, (1)H NMR and cyclic voltammetry studies. The UV/Vis spectroscopic response upon complexation with Sc(3+) or Eu(3+) as the triflate salts is rather unselective and nonlinear in going from the least to the most π-extended chromophore. Binding studies in MeCN, analyzed via equilibrium-restricted factor analysis, give values between log K(a) = 1.21 and 3.07 and affirm a 1 : 1 stoichiometry of the host:guest complexes in all cases. On the other hand, cyclic voltammetry reveals a selectivity in the response to Sc(3+) coordination over Ln(3+) (Eu(3+), but also Lu(3+) and Er(3+) were tested) for the two shorter chromophores, whereas the ligand with the longest π-bridge is able to sense Er(3+) (ΔE(1/2) complexed/uncomplexed chromophore = 20 mV) selectively over the other lanthanides.
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http://dx.doi.org/10.1039/c1dt11031dDOI Listing
November 2011

Mild preparation of functionalized [2.2]paracyclophanes via the Pummerer rearrangement.

Org Biomol Chem 2011 Jul 14;9(14):5018-20. Epub 2011 Apr 14.

Department of Chemistry and INSTM Research Unit, University of Pavia, Viale Taramelli 10, 27100, Pavia, Italy.

[2.2]Paracyclophanes, incorporating functional groups in the aliphatic bridges, suitable for elimination to give [2.2]paracyclophanedienes, are synthesized through a novel approach. It relies on a double Pummerer rearrangement on dithiacyclophane precursors, followed by ring contraction through a photochemical sulfur extrusion, and it is compatible with aryl moieties possessing very different electronic properties.
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http://dx.doi.org/10.1039/c1ob05319aDOI Listing
July 2011

Preprocedure hyperglycemia is more strongly associated with restenosis in diabetic patients after percutaneous coronary intervention than is hemoglobin A1C.

Cardiovasc Revasc Med 2007 Jan-Mar;8(1):15-20

Division of Cardiology, Washington Hospital Center, Washington, DC 20010, USA.

Background: Although more frequent in diabetic patients, restenosis after percutaneous coronary intervention (PCI) is less common in those with good glycemic control. High circulating insulin levels may also be associated with more frequent restenosis.

Methods: Fasting blood samples were obtained from 162 diabetic patients immediately prior to the PCI and analyzed for glucose, hemoglobin A1C, and insulin. Nine-month follow-up information was obtained in 145 (89.5%) patients. Target vessel revascularization (TVR) was the surrogate for restenosis.

Results: Patients were divided into quartiles with regard to their blood levels. Insulin, calculated insulin resistance, and hemoglobin A1C were not associated with increased TVR rates. Glucose level was significantly associated (P=.02). Patients in the two lower quartiles (glucose < or = 128 mg/dl) had a 9-month TVR rate of 12.7% while those in the two higher quartiles (>128 mg/dl) had a rate of 33.8% (P=.005). Level of glucose was independent of hemoglobin A1C. In patients whose A1C level was < or = 7%, the TVR rate was greater in those with a glucose level >128 mg/dl (39.1% vs. 10.6%, P=.009). Similarly, in patients with a hemoglobin A1C level >7%, the TVR rate was lower in patients with a glucose level < or = 128 mg/dl, but this difference did not reach statistical significance (16.6% vs. 31.3%, P=.3).

Conclusions: Hemoglobin A1C, insulin, and insulin resistance at the time of the PCI are not associated with restenosis. Periprocedural hyperglycemia may promote restenosis in diabetics.
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http://dx.doi.org/10.1016/j.carrev.2006.10.002DOI Listing
April 2007

Major noncardiac surgery following coronary stenting: when is it safe to operate?

Catheter Cardiovasc Interv 2004 Oct;63(2):141-5

Division of Cardiology, Washington Hospital Center, Washington, District of Columbia 20010, USA.

The optimal timing for elective noncardiac surgery (NCS) after coronary stenting is uncertain. We identified 47 patients who underwent elective NCS within 90 days of coronary stent placement between January 1995 and December 2000. Twenty-seven patients had NCS within 3 weeks of coronary stenting. Six of the seven in whom thienopyridine antiplatelet therapy was discontinued died postoperatively in a manner suggestive of stent thrombosis. In contrast, only 1 of the 20 patients in whom the thienopyridine was continued through the NCS died. The frequency of perioperative hemorrhage was similar whether or not the antiplatelet agent was continued. Only 1 perioperative death occurred in the 20 patients with NCS more than 3 weeks following stenting.
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http://dx.doi.org/10.1002/ccd.20124DOI Listing
October 2004

Usefulness of periprocedural creatinine phosphokinase-MB release to predict adverse outcomes after intracoronary radiation therapy for in-stent restenosis.

Am J Cardiol 2004 Feb;93(3):313-7

Royal Melbourne Hospital, Melbourne, Australia.

We aimed to analyze periprocedural creatinine phosphokinase (CPK)-MB elevation in patients treated with intracoronary radiation therapy (IRT) for in-stent restenosis (ISR) to risk stratify these patients. The clinical significance of periprocedural CPK-MB elevation after IRT for ISR is unknown. An elevated CPK-MB has been associated with increased mortality after conventional angioplasty. We evaluated 1,326 patients who were enrolled in radiation trials for ISR at the Washington Hospital Center using gamma- and beta-emitters. Patients were analyzed according to degree of CPK-MB increase within 24 hours of the index IRT procedure (normal CPK-MB, CPK-MB 1 to 3 times the upper limit of normal, or CPK-MB >3 times the upper limit of normal). Patients with CPK-MB >3 times the upper limit of normal were older (64 +/- 12 years, p = 0.04), more likely to be smokers (64%, p = 0.04), hypertensive (85%, p <0.01), and diabetic (49%, p = 0.04). The cohort with the highest CPK-MB release (CPK-MB >3 times the upper limit of normal) had significantly higher rates of adverse clinical events at 12 months (major adverse cardiac events 40%, p <0.01), including death (9.3%, p <0.01) and late thrombosis (6.3%, p <0.01). Periprocedural CPK-MB elevation is of prognostic importance in patients treated with IRT for ISR, and its analysis appears to be mandatory to risk stratify these patients. The impact of glycoprotein IIb/IIIa antagonists in reducing periprocedural CPK-MB release awaits evaluation.
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http://dx.doi.org/10.1016/j.amjcard.2003.10.010DOI Listing
February 2004

Spontaneous coronary artery dissection in a patient with systemic lupus erythematosis.

Hawaii Med J 2003 Nov;62(11):248-53

Division of Cardiology, Washington Hospital Center, USA

Spontaneous coronary artery dissection (SCAD) is an uncommon condition that may lead to sudden coronary artery occlusion resulting in a fatal acute myocardial infarction. It usually affects young to middle age women. A Medline search from 1966 to 2001 (using keywords: coronary artery dissection and systemic lupus erythematosis) revealed no prior reports of coronary dissection in a patient with systemic lupus erythematosis (SLE). We describe a 48-year old woman with SLE who sustained a fatal spontaneous left main coronary artery dissection. Coronary angiogram was notable for marked variability in the size of coronary lumen from systole to diastole. This case demonstrates the need to consider SCAD in the evaluation of chest pain and myocardial infarction in patients with SLE. Furthermore, in the absence of classical angiographic findings of coronary dissection, a detailed review of phasic changes in coronary lumen during a cardiac cycle could help reach this diagnosis.
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November 2003

Acute procedural complications and in-hospital events after percutaneous coronary interventions: eptifibatide versus abciximab.

Cardiovasc Radiat Med 2003 Jan-Mar;4(1):12-7

Washington Hospital Center, 110 Irving Street, NW, Suite 4B-1, Washington, DC 20010, USA.

Background: Glycoprotein IIb/IIIa antagonists reduce peri-angioplasty ischemic complications and improve in-hospital outcome in patients undergoing percutaneous coronary interventions (PCI). Prior studies have demonstrated favorable results with both eptifibatide and abciximab. The purpose of this study was to assess whether there are any differences in rates of acute procedural complications and in-hospital events with the use of these two agents.

Methods: A retrospective review of 359 elective PCIs from June 1998 to August 2000 identified 152 PCIs treated with eptifibatide (bolus 180 microg/kg, infusion 2 microg/kg/min for 12-48 h) and 205 PCIs treated with abciximab (bolus 0.25 mg/kg, infusion 10 microg/min for 12 h). All patients received IIb/IIIa antagonists at the initiation of the intervention.

Results: The clinical demographics, the angiographic morphology, the indications, and the procedural details were similar in both groups. In the eptifibatide group, the maximum ACT was lower (235+/-45 vs. 253+/-40, P<.0001). The incidence of major procedural and in-hospital events was compared. Eptifibatide and abciximab had similar rates of major complications (death or myocardial infarction) (1.4% vs. 2.9%), repeat PTCA (3.4% vs. 1.9%), and major bleeding (3.3% vs. 4.3%).

Conclusions: Eptifibatide is comparable to abciximab in regards to acute procedural complications and in-hospital events after PCI.
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http://dx.doi.org/10.1016/s1522-1865(03)00120-3DOI Listing
January 2004

Clinical outcomes following stent implantation in internal mammary artery grafts.

Catheter Cardiovasc Interv 2003 Aug;59(4):436-41

Department of Cardiology, Washington Hospital Center, Washington, DC 20010, USA.

We evaluated our experience with percutaneous coronary intervention (PCI) of internal mammary artery (IMA) grafts. From the institution's database we identified 288 patients with 311 IMA lesions. Of these, 82 (26.4%) had stents placed during PCI. Angiographic success was 92%. Mortality at 1 month was 1.7%, myocardial infarction (MI) 15.7%, and target lesion revascularization (TLR) 0.4%. Cumulative 1-year event rates were mortality 6.4%, MI 20.4%, and TLR 8.0%. TLR rates were significantly higher in the stented lesions than lesions treated with angioplasty alone (19.2% vs. 4.9%; P = 0.004). The higher TLR rate in stented lesions was most apparent at the anastomotic site (25.0% vs. 4.2%; P = 0.006). Percutaneous revascularization of IMA grafts can be performed safely with high procedural success and excellent short- and long-term results. Stenting, particularly at the anastomotic site, was associated with significantly greater rates of TLR than angioplasty alone.
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http://dx.doi.org/10.1002/ccd.10580DOI Listing
August 2003

Troponin-I elevation in patients with increased left ventricular mass.

Am J Cardiol 2003 Jul;92(1):88-90

Department of Cardiology, Washington Hospital Center, Washington, DC 20010, USA.

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http://dx.doi.org/10.1016/s0002-9149(03)00477-6DOI Listing
July 2003

Percutaneous interventions in radial artery grafts: clinical and angiographic outcomes.

Catheter Cardiovasc Interv 2003 Jun;59(2):172-5

Division of Cardiology, Washington Hospital Center, Washington, DC 20010, USA.

In the modern era, radial artery graft is being used with increasing frequency to replace saphenous vein as a conduit for coronary artery bypass surgery. Several reports have shown encouraging early results of radial grafts compared to saphenous grafts. Despite these advantages, radial artery graft failure requiring revascularization does occur. We report on the clinical, angiographic, and technical characteristics and the follow-up results of 22 patients who underwent percutaneous intervention of radial grafts.
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http://dx.doi.org/10.1002/ccd.10527DOI Listing
June 2003

Comparison of intracoronary gamma radiation for in-stent restenosis in saphenous vein grafts versus native coronary arteries.

Am J Cardiol 2003 Jan;91(1):22-6

Cardiovascular Research Institute, Washington Hospital Center, Washington, DC 20010, USA

Intracoronary gamma radiation is effective in reducing recurrent in-stent restenosis (ISR) involving native coronary arteries. This study compares the effectiveness and safety of intracoronary gamma radiation for the treatment of ISR in saphenous vein grafts (SVGs) versus native coronary arteries. In the Washington Radiation for In-Stent restenosis Trial (WRIST) series of gamma radiation trials, 1,142 patients with ISR (230 in SVG and 912 in native coronary arteries) completed 6-month clinical follow-up. All patients underwent balloon angioplasty, atherectomy, and/or restenting. Different ribbon lengths containing 6 to 23 seeds of iridium-192 were used to cover lesion lengths <80 mm. The prescribed radiation doses were 14 or 15 Gy at 2-mm radial distance from the center of the source. Baseline demographics showed that patients with SVGs were older (65 +/- 13 vs 61 +/- 11 years, p <0.001), more likely male (79% vs 64%, p <0.001), had more multivessel coronary disease (81% vs 50%, p <0.001), and less diffuse lesions (17 +/- 10 vs 24 +/- 12 mm, p <0.001). At 6 months, event-free survival was similar for patients with SVG ISR and native coronary ISR (82% vs 84%, p = 0.35). The SVG ISR population had a low rate of late total occlusion (4.6%) and late thrombosis (3.5%). Thus, treatment of ISR with gamma radiation in SVGs had similar outcome to native coronary arteries. The use of gamma radiation for the treatment of ISR should expand to SVGs.
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http://dx.doi.org/10.1016/s0002-9149(02)02992-2DOI Listing
January 2003

Acute myocardial infarction and Friedreich's ataxia.

Hawaii Med J 2002 Sep;61(9):199-201, 212

Washington Hospital Center, Division of Cardiology, 110 Irving St NW, Washington, DC 20010, USA.

While cardiac disease is noted in 90% of patients with Friedreich's ataxia (FRDA), the finding of coronary artery disease is unusual. To the best of our knowledge only two cases of acute myocardial infarction (AMI) has been reported in patients with FRDA. Large vessel CAD has not been reported previously in patients with FRDA. We report a young patient with AMI and obstruction of large epicardial arteries.
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September 2002
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