Publications by authors named "Alireza Maleki"

11 Publications

  • Page 1 of 1

Lifetime-Engineered Ruby Nanoparticles (Tau-Rubies) for Multiplexed Imaging of μ-Opioid Receptors.

ACS Sens 2021 03 4;6(3):1375-1383. Epub 2021 Mar 4.

MQ Photonics, Faculty of Science and Engineering, Macquarie University, Sydney, 2109, Australia.

To address the growing demand for simultaneous imaging of multiple biomarkers in highly scattering media such as organotypic cell cultures, we introduce a new type of photoluminescent nanomaterial termed "tau-ruby" composed of ruby nanocrystals (AlO:Cr) with tunable emission lifetime. The lifetime tuning range from 2.4 to 3.2 ms was achieved by varying the Cr dopant concentration from 0.8% to 0.2%, affording facile implementation of background-free detection. We developed inexpensive scalable production of tau-ruby characterized by bright emission, narrow spectrum (693 ± 2 nm), and virtually unlimited photostability upon excitation with affordable excitation/detection sources, noncytotoxic and insensitive to microenvironmental fluctuations. By functionalizing the surface of tau-rubies with targeting antibodies, we obtained different biomarkers suitable for multiplexed lifetime imaging. As a proof of principle, three tau-ruby bioprobes, characterized by three mean lifetimes, were deployed to label three μ-opioid receptor species expressed on transfected cancer cells, each fused to a unique epitope, so that three types of cells were lifetime-encoded. Robust decoding of photoluminescent signals that report on each cell type was achieved by using a home-built lifetime imaging system and resulted in high-contrast multiplexed lifetime imaging of the cells.
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March 2021

Identification of Organic Matter Dispersions Based on Light Scattering Matrices Focusing on Soil Organic Matter Management.

ACS Omega 2020 Dec 16;5(51):33214-33224. Epub 2020 Dec 16.

All-Russia Research Institute for Phytopathology of the Russian Academy of Sciences, Big Vyazyomy, Moscow Region 143050, Russia.

The origin of organic matter, its spread, scattering, and functioning are influenced by the physical structure of liquid or dispersed media of organic matter. Refractive indices of fodder yeast grown on paraffin oil (paprin) and natural gas (gaprin) as well as Lycoperdon spore and organelles were measured by laser phase microscopy. The scattering matrices of aqueous suspensions of paprin, gaprin, and Lycoperdon spores were measured using a laser polarimeter with the scattering angle ranging from 20 to 150°. The experimentally measured scattering matrices have been approximated by the weighted sum of theoretically calculated scattering matrices using the T-matrix code developed by Mishchenko. Most of the particle radii in the filtered fraction of paprin and gaprin were within the range of about 0.05-0.12 μm. Particle radii of the Lycoperdon spore suspension were within the range of 0.4-2.4 μm, which corresponded to both whole spores and their separate organelles. A possibility of identifying a suspension by its scattering matrices was shown for a small difference in the real parts of the refractive index in the example of paprin and gaprin. The measurements of the light scattering matrix showed that for a small size parameter of about 1, the identification of paprin and gaprin can be based only on a difference in the particle shape. Refractive index difference is manifested for the size parameter values higher than 3. An example of a suspension consisting of micron-sized spores and their submicron organelles shows high sensitivity of the scattering matrix to the composition of the dispersed material. The presented data and models help to extrapolate the results of the light scattering matrix study to a vast spectrum of media of organic matter origin and functioning. This study focused on the Biogeosystem Technique (BGT*) transcendental methodology to manage soil as an arena of biodegradation and organic synthesis. A BGT*-based robotic system for intra-soil pulse continuous-discrete water and matter supply directly into the dispersed-aggregated physical structure of the soil media was developed. The system enables transformation of soil into a stable highly productive organic chemical bioreactor for better controlled nanoparticle biomolecular interactions and adsorption by biological and mineral media. The scattering matrix measurement unit is supposed to be used in the robotic system as a diagnostic tool for the dispersion composition of soil organic components.
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December 2020

The First Inherited Retinal Disease Registry in Iran: Research Protocol and Results of a Pilot Study.

Arch Iran Med 2020 07 1;23(7):445-454. Epub 2020 Jul 1.

Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Background: To describe the protocol for developing a national inherited retinal disease (IRD) registry in Iran and present its initial report.

Methods: This community-based participatory research was approved by the Ministry of Health and Medical Education of Iran in 2016. To provide the minimum data set (MDS), several focus group meetings were held. The final MDS was handed over to an engineering team to develop a web-based software. In the pilot phase, the software was set up in two referral centers in Iran. Final IRD diagnosis was made based on clinical manifestations and genetic findings. Ultimately, patient registration was done based on all clinical and non-clinical manifestations.

Results: Initially, a total of 151 data elements were approved with Delphi technique. The registry software went live at www. based on DHIS2 open source license agreement since February 2016. So far, a total of 1001 patients have been registered with a mean age of 32.41±15.60 years (range, 3 months to 74 years). The majority of the registered patients had retinitis pigmentosa (42%, 95% CI: 38.9% to 45%). Genetic testing was done for approximately 20% of the registered individuals.

Conclusion: Our study shows successful web-based software design and data collection as a proof of concept for the first IRD registry in Iran. Multicenter integration of the IRD registry in medical centers throughout the country is well underway as planned. These data will assist researchers to rapidly access information about the distribution and genetic patterns of this disease.
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July 2020

Does Preoperative or Postoperative Graft Thickness Influence Postoperative Visual Acuity in Descemet Stripping Automated Endothelial Keratoplasty for Advanced Pseudophakic Bullous Keratopathy?

Cornea 2019 Nov;38(11):1358-1363

Opthalmology Department, Thionville Metz Regional Hospital, Mercy Hospital, Metz, France.

Purpose: To describe the evolution of best spectacle-corrected visual acuity (BSCVA) after Descemet stripping automated endothelial keratoplasty (DSAEK) for very advanced pseudophakic bullous keratopathy (PBK) and to determine whether the thickness of corneal grafts in DSAEK surgery for advanced PBK correlates with BSCVA 6 months postoperatively.

Methods: In a prospective, single-center, observational study, 141 eyes treated with DSAEK surgery were studied, from patients requiring posterior lamellar transplantation for advanced PBK. Graft thickness was measured during the surgery and in vivo 6 months later. The primary end point was BSCVA in LogMAR at 6 months.

Results: BSCVA 6 months after surgery was slightly correlated with 6 months graft thickness (r = 0.24, P = 0.01), but not with preoperative graft thickness (r = 0.01, P = 0.93). After adjusting for preoperative BSCVA, a better 6 months BSCVA was best associated with thinner grafts at 6 months (P < 0.01), but not with preoperative graft thickness (P = 0.80).

Conclusions: BSCVA after DSAEK was significantly related to graft thickness measured 6 months after surgery, suggesting that better BSCVA after DSAEK is related to a decrease in graft thickness after surgery and not to the use of a thinner graft during surgery. This decrease may be because of the good health of the endothelium, but this result may be biased because of the intrastromal scars inherent in severe PBK. This study shows that DSAEK is a good option for advanced PBK but has low visual acuity potential recovery because of stromal scarring. Therefore, a penetrating keratoplasty may be indicated to obtain maximal recovery of visual acuity or for monocular patients.
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November 2019

The Effect of Intravitreal Bevacizumab on Central Serous Chorioretinopathy.

Med Hypothesis Discov Innov Ophthalmol 2018 ;7(4):176-182

Department of Epidemiology and Biostatistics, Tehran University of Medical Sciences, Tehran, Iran.

The aim of this study was to investigate the efficacy of Intravitreal Injection of Bevacizumab (IVB) in patients with Central Serous Chorioretinopathy (CSC) compared to the control group, after four months of injection. In this study, 30 eyes of 30 patients with CSC, who were in the age range of 23 to 50 years old (70% male subject) were included. Eligible patients were randomly allocated to the intervention (n = 15) and control groups (n = 15). Patients in the intervention group received a single dose injection of bevacizumab (1.25 mg in 0.05 mL), while patients in the control group were followed-up during the same time interval, without any medical interventions. Corrected Distance Visual Acuity (CDVA) and Central Macular Thickness (CMT) were evaluated as the primary outcome measures at the four-month follow-up. There was no statistically significant difference between the intervention and control groups regarding their baseline characteristics. Corrected Distance Visual Acuity was improved significantly in the intervention group (P < 0.001), while this improvement was not observed in the control group. Furthermore, greater improvement of CDVA was detected in the IVB group compared to the patients without injection (P = 0.018). The CMT findings were in line with CDVA changes in both groups, revealing a significant reduction of CMT only in the intervention group (P < 0.001). Also, thinner central retina was found in the intervention group compared to the comparison group, at the four-month follow-up (P < 0.001). Based on the findings, bevacizumab could be effective for improvement of both anatomical and functional outcomes in patients with CSC.
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January 2018

Comparative Evaluation of Tacrolimus Versus Interferon Alpha-2b Eye Drops in the Treatment of Vernal Keratoconjunctivitis: A Randomized, Double-Masked Study.

Cornea 2017 Jun;36(6):675-678

*Department of Ophthalmology, Alzahra Eye Hospital, Zahedan University of Medical Sciences, Zahedan, Iran; †Eye Research Center, Department of Ophthalmology, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran; ‡Cancer Research Center, Semnan University of Medical Sciences, Semnan, Iran; §Department of Ophthalmology, Isfahan Eye Research Center, Isfahan University of Medical Sciences, Isfahan, Iran; and ¶Department of Epidemiology and Biostatistics, Zahedan University of Medical Sciences, Zahedan, Iran.

Purpose: Vernal keratoconjunctivitis (VKC) is a bilateral, chronic, external ocular inflammatory disorder that mainly affects patients in their first or second decade. This study was designed to compare tacrolimus and interferon alpha-2b (IFN alpha-2b) eye drops in the treatment of VKC.

Methods: In this randomized, double-masked clinical trial, 40 consecutive patients with VKC were sent to a referral eye hospital in a tropical region southeast of Iran. Patients were randomly assigned to receive either 0.005% tacrolimus or IFN alpha-2b (1,000,000 units/cc). Chi-square and t tests were used for comparison of outcomes between both groups.

Results: Mean ± SD age was 11.1 ± 5.2 years. Thirty-one patients (77.5%) were male. The mean duration of disease was 3.4 ± 2.9 years. In this study, the signs and symptoms were significantly reduced in patients after treatment in both groups (P = 0.0001). In the tacrolimus group, all patients responded to treatment whereas only one subject in the IFN group failed to respond (P = 0.99). Side effects in both groups were mild and tolerable.

Conclusions: This study indicated that both 0.005% tacrolimus and IFN alpha-2b are effective and appear to be safe in treatment of recalcitrant VKC.
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June 2017

Diabetic Retinopathy Clinical Practice Guidelines: Customized for Iranian Population.

J Ophthalmic Vis Res 2016 Oct-Dec;11(4):394-414

Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Purpose: To customize clinical practice guidelines (CPGs) for management of diabetic retinopathy (DR) in the Iranian population.

Methods: Three DR CPGs (The Royal College of Ophthalmologists 2013, American Academy of Ophthalmology [Preferred Practice Pattern 2012], and Australian Diabetes Society 2008) were selected from the literature using the AGREE tool. Clinical questions were designed and summarized into four tables by the customization team. The components of the clinical questions along with pertinent recommendations extracted from the above-mentioned CPGs; details of the supporting articles and their levels of evidence; clinical recommendations considering clinical benefits, cost and side effects; and revised recommendations based on customization capability (applicability, acceptability, external validity) were recorded in 4 tables, respectively. Customized recommendations were sent to the faculty members of all universities across the country to score the recommendations from 1 to 9.

Results: Agreed recommendations were accepted as the final recommendations while the non-agreed ones were approved after revision. Eventually, 29 customized recommendations under three major categories consisting of screening, diagnosis and treatment of DR were developed along with their sources and levels of evidence.

Conclusion: This customized CPGs for management of DR can be used to standardize the referral pathway, diagnosis and treatment of patients with diabetic retinopathy.
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December 2016

Ocular dirofilariasis by Dirofilaria immitis in a child in Iran: A case report and review of the literature.

Parasitol Int 2017 Feb 1;66(1):978-981. Epub 2016 Nov 1.

Department of Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Students Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address:

This report describes a rare case of ophthalmic dirofilariasis in a 2-year-old boy with redness, irritation, pain and foreign body sensation in the right eye. Slit lamp examination demonstrated a thread-like whitish nematode in the anterior chamber of the right eye that twisted around itself. The nematode worm (35mm long and 150-200μm width) was removed surgically. The presence of the smooth cuticular surface without longitudinal ridges and the vulva showed that it could be a female Diroflaria immitis. PCR amplification was done to verify the Diroflaria species. PCR amplification and sequence analysis of mitochondrial 12S rDNA confirmed that recovered worm was D. immitis. Ocular dirofilariasis caused by D. immitis is very rare, but it must be considered in humans living in endemic areas.
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February 2017

A comparison of the antibacterial activity of the two methods of photodynamic therapy (using diode laser 810 nm and LED lamp 630 nm) against Enterococcus faecalis in extracted human anterior teeth.

Photodiagnosis Photodyn Ther 2016 Mar 1;13:233-237. Epub 2015 Aug 1.

Laser Application in Medical Sciences Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Background: Failure of endodontic treatment is usually due to an inadequate disinfection of the root canal system. Enterococcus faecalis has been widely used as a valuable microbiological marker for in-vitro studies because of its ability to colonize in a biofilm like style in root canals, invading dentinal tubules and resistance to some endodontic treatments. The aim of this study was to investigate the antibacterial effects of two methods of photodynamic therapy using a light emitting diode lamp (LED lamp, 630 nm) and a diode laser (810 nm) on E. faecalis biofilms in anterior extracted human teeth.

Methods: Fifty six single-rooted extracted teeth were used in this study. After routine root canal cleansing, shaping and sterilization, the teeth were incubated with E. faecalis for a period of two weeks. Teeth were then divided into two experimental groups (nu=23) and two control groups (nu=5). Teeth in one experimental group were exposed to a diode laser (810 nm), and in the other group samples were exposed to a LED lamp (630 nm). Intracanal bacterial sampling was done, and bacterial survival rate was then evaluated for each group.

Results: The Colony Forming Unit (CFU) in LED group (log10 CFUs=4.88±0.82) was significantly lower than the laser group (log CFUs=5.49±0.71) (p value=0.021). CFUs in positive control group (Log10 CFUs=10.96±0.44) were significantly higher than the treatment group (p˂0.001). No bacterial colony was found in negative control group.

Conclusion: The results of this research show that photodynamic therapy could be an effective supplement in root canal disinfection. PDT using LED lamp was more effective than diode laser 810 nm in reducing CFUs of E. faecalis in human teeth.
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March 2016

Intravitreal autologous plasmin prepared by urokinase for vitreolysis: a pilot study.

Eur J Ophthalmol 2016 Jan-Feb;26(1):67-70. Epub 2015 May 27.

Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran - Iran.

Purpose: To evaluate the effects of intravitreal autologous plasmin injection (IVAP) on vitreoretinal diseases and vitreolysis.

Methods: In this interventional, prospective, case series pilot study, 8 eyes were assigned to IVAP. Plasminogen as centrifuged from the patients' plasma was converted to plasmin by adding urokinase. A total of 0.2 mL extracted plasmin was injected intravitreally. Posterior vitreous detachment (PVD) and potential injection-related complications at week 4 were the primary outcome measures. Secondary outcomes included changes in best-corrected visual acuity (VA) (logMAR) and central macular thickness (CMT).

Results: Mean age of the patients was 54.35 years. Two patients had complete PVD and 3 patients had partial PVD. Four patients had decrease in CMT. The VA was not changed in 6 patients, improved in 1 patient, and decreased in 1 patient. No uveitis, endophthalmitis, or postinjection vitreous hemorrhage was observed.

Conclusions: This pilot study demonstrated the efficacy of urokinase-prepared IVAP injection on releasing vitreomacular traction and inducing vitreolysis.
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April 2016

The effect of gag reflex on cardiac sympatovagal tone.

Oman Med J 2012 May;27(3):249-50

Objectives: Heart velocity may be influenced by gagging. The medulla oblongata receives the afferents of gag reflex. Neuronal pools of vomiting, salivation and cardiac parasympathetic fibers are very close in this area. So, their activities may be changed by spillover from each other. Using the heart rate variability (HRV) analysis, the effect of gagging on cardiac sympatovagal balance was studied.

Methods: ECG was recorded from 12 healthy nonsmoker volunteer students for 10 minutes in the sitting position between 10 and 11 AM. Gagging was elicited by tactile stimulation of the posterior pharyngeal wall. At 1 kHz sampling rate, HRV was calculated. The mean of heart rate at low and high frequencies (LF: 0.04-0.15; HF: 0.15-0.4 Hz) were compared before and after the stimulus.

Results: The mean of average heart rate, LF and HF in normalized units (nu) and the ratio of them (LF/HF) before and after the gagging were 89.9 ± 3 and 95.2 ± 3 bpm; 44.2 ± 5.8 and 21.2 ± 4; 31.1 ± 5.3 and 39.4 ± 3.8; and 1.7 ± 0.3 and 0.6 ± 0.2 respectively.

Conclusion: Gagging increased heart velocity and had differential effect on two branches of cardiac autonomic nerves. The paradoxical relation between average heart rate and HRV indexes of sympatovagal tone may be due to unequal rate of change in autonomic fiber activities which is masked by 5 minutes interval averaging.
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May 2012