Aastha Singh - Academia.edu (original) (raw)

Papers by Aastha Singh

Cornea, 2020

PURPOSE Severe vernal keratoconjunctivitis (VKC) can cause ocular surface disease including parti... more PURPOSE Severe vernal keratoconjunctivitis (VKC) can cause ocular surface disease including partial or complete limbal stem cell deficiency (LSCD), especially in early-onset and severe limbal form of VKC. We report a novel technique of doughnut amniotic membrane transplantation (AMT) along with penetrating keratoplasty (PK) for management of partial LSCD and corneal scarring in a case of severe VKC. METHODS Case report. RESULTS A 17-year-old boy, with onset of disease at 8 years of age, and development of partial LSCD and corneal scarring over a period of 9 years despite therapy, presented with profound visual loss due to dense bilateral corneal scarring. After the active allergy subsided, he underwent modified AMT (doughnut AMT) with simultaneous PK in his left eye. Histopathology of the excised button revealed conjunctival phenotype and dense corneal scarring up to the posterior stroma. At 1-year follow up, his best spectacle-corrected visual acuity was maintained at 20/30 in the operated eye, the graft was clear, and the ocular surface was stable. CONCLUSIONS Severe VKC can cause ocular surface disease including LSCD with corneal scarring, especially in early-onset limbal form of VKC. The modified technique of AMT (doughnut AMT) along with PK can successfully visually rehabilitate and address partial LSCD in such patients.

Frontiers in Pharmacology, 2021

Exosomes are a subset of extracellular vesicles (EVs) that are secreted by most cell types. They ... more Exosomes are a subset of extracellular vesicles (EVs) that are secreted by most cell types. They are nanosized EVs ranging from 30 to 150 nm. The membrane-enclosed bodies originate by the process of endocytosis and mainly comprise DNA, RNA, protein, and lipids. Exosomes not only act as cell-to-cell communication signaling mediators but also have the potential to act as biomarkers for clinical application and as a promising carrier for drug delivery. Unfortunately, the purification methods for exosomes remain an obstacle. While most of the exosome researches are mainly focused on cancer, there are limited studies highlighting the importance of exosomes in ocular biology, specifically cornea-associated pathologies. Here, we summarize a brief description of exosome biogenesis, roles of exosomes and exosome-based therapies in corneal pathologies, and exosome bioengineering for tissue-specific therapy.

Frontiers in Medicine, 2021

Simple limbal epithelial transplantation (SLET) is an ingenious, low cost and effective technique... more Simple limbal epithelial transplantation (SLET) is an ingenious, low cost and effective technique of limbal stem cell transplantation (LSCT) that is increasingly being undertaken in practice across the world. Since it was first described a decade ago, the technique has been performed in a variety of cases of limbal stem cell deficiency (LSCD) and has underwent several innovative modifications. Published literature on SLET has progressively increased over time and successful outcomes in various clinical scenarios have been reported. This concise review attempts to present a crisp account of SLET covering the indications and contraindications of performing the procedure; detailed account of pre-operative work up and preparation; surgical technique and its modifications; post-operative course, care and possible complications as well as published outcomes of surgery from across the world. Comparative analysis of various techniques of LSCT have been discussed and common concerns of surge...

UNIVERSITY JOURNAL OF DENTAL SCIENCES, 2020

Pemphigus vulgaris (PV) is a potentially life threatening and rare mucocutaneous disease that usu... more Pemphigus vulgaris (PV) is a potentially life threatening and rare mucocutaneous disease that usually manifests first in the oral cavity and may later spread to the skin or other mucous membrane. Lesions may occur anywhere on the mucosa but it is unusual for PV to present over the gingiva as a primary site of involvement. A 64 year old female patient reported with a chief complaint of reddish, painful gums with burning sensation since 8 years. The diagnosis of PV is based on clinical findings (Nikolsky’s sign positive) and confirmed by histopathological analysis. Medications were prescribed as per indications and requirements. Oral hygiene instructions were given. No recurrence was observed at 1½ year of follow-up. Thus, this case serves to enhance our awareness of gingiva as a site at which systemic disease can manifests itself.

Indian Journal of Ophthalmology, 2019

In the methods section, it is mentioned that three consecutive central corneal thickness (CCT) me... more In the methods section, it is mentioned that three consecutive central corneal thickness (CCT) measurements were taken with the non‐contact devices. For the ultrasonic pachymetry (UP) measurement, the number of measurements performed was not mentioned. Was it a mean of three measurements or mean of nine measurements, as recommended by the manufacturer for this UP (PachPen; Accutome Inc, Malvern, PA)?

Indian Journal of Ophthalmology, 2019

Why some 10 years after investing heavily in the technique of laboratory expanded corneal epithel... more Why some 10 years after investing heavily in the technique of laboratory expanded corneal epithelial cells for the treatment of limbal stem cell deficiency (LSCD) did the group of Virender Singh Sangwan (VSS) apparently turn their back on this and started using small explants of the cornea to treat LSCD? This technique of using small limbal explants was called "SLET or simple limbal epithelial transplantation." The technique of cultivated limbal epithelial stem cell transplantation (CLET) works quite well in those groups who have established it. However, the bottom line is that despite some 17 years of its use with reasonably good success by all groups involved, it fails one critical test: it fails to reach a large number of patients because it requires a high level of infrastructure investment. To culture autologous corneal cells requires highly trained specialist cell culture staff working in dedicated premises under highly regulated conditions that meet the standard of the local regulatory authority. As such, it is beyond the reach of the majority of ophthalmic surgeons and patients suffering from LSCD who could benefit from it.

Hunter's Point South Waterfront Park, 2018

This investigation was conducted as part of the Landscape Architecture Foundation's 2018 Case Stu... more This investigation was conducted as part of the Landscape Architecture Foundation's 2018 Case Study Investigation (CSI) program. CSI matches faculty-student research teams with design practitioners to document the benefits of exemplary high-performing landscape projects. Teams develop methods to quantify environmental, economic and social benefits and produce Case Study Briefs for LAF's Landscape Performance Series.

International Journal of Public Health

Many reviews have been conducted on the economic evaluation of the HPV vaccine in global north co... more Many reviews have been conducted on the economic evaluation of the HPV vaccine in global north countries. But there is a dearth of such reviews in the Global South countries. Hence, this systematic review aims to summarize studies done in these countries. Four databases PubMed, Embase, Cochrane Library, and Google Scholar from 2009 to 2019 were searched for economic evaluations on HPV vaccination in the Global South countries. PRISMA guidelines were followed to include full-text articles. 40 original articles were shortlisted for full-text review. Studies had varied models, assumptions, and results according to different scenarios. Most studies concluded HPV vaccination to be cost-effective under varied scenarios and vaccine cost was the most influential parameter affecting the sensitivity analyses, consequently incremental cost-effectiveness ratio. A wide range in the cost-effectiveness ratio was observed in the included studies due to different study settings, populations, and inconsistencies in modeling practices (variations in methodological approaches). This review suggests the introduction of HPV vaccination alone or in combination with screening according to different countries. The price of the vaccine should be economical and funds for the vaccine should be provided by public sector firms.

Chemical Biology & Drug Design, 2016

Benzylidene indanones have been designed and synthesized from gallic acid, a plant phenolic acid ... more Benzylidene indanones have been designed and synthesized from gallic acid, a plant phenolic acid as possible anticancer agent. The best analogue of the series, that is, 3-(3',4',5'-trimethoxyphenyl)-4,5,6-trimethoxy-2-(4˝-nitrobenzylidene)-indan-1-one (8) exhibited potent cytotoxicity (IC50 =3-10 μm) against several human cancer cell lines through microtubule destabilization (IC50 =1.54 μm) after occupying colchicine-binding site of β-tubulin. In cell cycle analysis, compound 8 exerted G2/M phase arrest in both MCF-7 and MDA-MB-231 cells and induced apoptosis. It reduced 34.8% solid tumor in in vivo Ehrlich ascite carcinoma in Swiss albino mice at 30 mg/kg dose. In acute oral toxicity experiment, it was tolerable up to 300 mg/kg doses in Swiss albino mice. The lead compound 8 needs to be optimized for better activity.

Corporations today bear a significant portion of an employee’s health care costs and play a proac... more Corporations today bear a significant portion of an employee’s health care costs and play a proactive role in their wellness care. Telewellness care leverages today’s technological ability to electronically exchange data, voice, video, and other types of information to deliver such care when the provider and the recipient are geographically separated. Corporations are adopting telewellness care to reduce costs and improve effectiveness.

West Point Foundry Preserve, Phase 1

Cornea, 2020

PURPOSE Severe vernal keratoconjunctivitis (VKC) can cause ocular surface disease including parti... more PURPOSE Severe vernal keratoconjunctivitis (VKC) can cause ocular surface disease including partial or complete limbal stem cell deficiency (LSCD), especially in early-onset and severe limbal form of VKC. We report a novel technique of doughnut amniotic membrane transplantation (AMT) along with penetrating keratoplasty (PK) for management of partial LSCD and corneal scarring in a case of severe VKC. METHODS Case report. RESULTS A 17-year-old boy, with onset of disease at 8 years of age, and development of partial LSCD and corneal scarring over a period of 9 years despite therapy, presented with profound visual loss due to dense bilateral corneal scarring. After the active allergy subsided, he underwent modified AMT (doughnut AMT) with simultaneous PK in his left eye. Histopathology of the excised button revealed conjunctival phenotype and dense corneal scarring up to the posterior stroma. At 1-year follow up, his best spectacle-corrected visual acuity was maintained at 20/30 in the operated eye, the graft was clear, and the ocular surface was stable. CONCLUSIONS Severe VKC can cause ocular surface disease including LSCD with corneal scarring, especially in early-onset limbal form of VKC. The modified technique of AMT (doughnut AMT) along with PK can successfully visually rehabilitate and address partial LSCD in such patients.

Frontiers in Pharmacology, 2021

Exosomes are a subset of extracellular vesicles (EVs) that are secreted by most cell types. They ... more Exosomes are a subset of extracellular vesicles (EVs) that are secreted by most cell types. They are nanosized EVs ranging from 30 to 150 nm. The membrane-enclosed bodies originate by the process of endocytosis and mainly comprise DNA, RNA, protein, and lipids. Exosomes not only act as cell-to-cell communication signaling mediators but also have the potential to act as biomarkers for clinical application and as a promising carrier for drug delivery. Unfortunately, the purification methods for exosomes remain an obstacle. While most of the exosome researches are mainly focused on cancer, there are limited studies highlighting the importance of exosomes in ocular biology, specifically cornea-associated pathologies. Here, we summarize a brief description of exosome biogenesis, roles of exosomes and exosome-based therapies in corneal pathologies, and exosome bioengineering for tissue-specific therapy.

Frontiers in Medicine, 2021

Simple limbal epithelial transplantation (SLET) is an ingenious, low cost and effective technique... more Simple limbal epithelial transplantation (SLET) is an ingenious, low cost and effective technique of limbal stem cell transplantation (LSCT) that is increasingly being undertaken in practice across the world. Since it was first described a decade ago, the technique has been performed in a variety of cases of limbal stem cell deficiency (LSCD) and has underwent several innovative modifications. Published literature on SLET has progressively increased over time and successful outcomes in various clinical scenarios have been reported. This concise review attempts to present a crisp account of SLET covering the indications and contraindications of performing the procedure; detailed account of pre-operative work up and preparation; surgical technique and its modifications; post-operative course, care and possible complications as well as published outcomes of surgery from across the world. Comparative analysis of various techniques of LSCT have been discussed and common concerns of surge...

UNIVERSITY JOURNAL OF DENTAL SCIENCES, 2020

Pemphigus vulgaris (PV) is a potentially life threatening and rare mucocutaneous disease that usu... more Pemphigus vulgaris (PV) is a potentially life threatening and rare mucocutaneous disease that usually manifests first in the oral cavity and may later spread to the skin or other mucous membrane. Lesions may occur anywhere on the mucosa but it is unusual for PV to present over the gingiva as a primary site of involvement. A 64 year old female patient reported with a chief complaint of reddish, painful gums with burning sensation since 8 years. The diagnosis of PV is based on clinical findings (Nikolsky’s sign positive) and confirmed by histopathological analysis. Medications were prescribed as per indications and requirements. Oral hygiene instructions were given. No recurrence was observed at 1½ year of follow-up. Thus, this case serves to enhance our awareness of gingiva as a site at which systemic disease can manifests itself.

Indian Journal of Ophthalmology, 2019

In the methods section, it is mentioned that three consecutive central corneal thickness (CCT) me... more In the methods section, it is mentioned that three consecutive central corneal thickness (CCT) measurements were taken with the non‐contact devices. For the ultrasonic pachymetry (UP) measurement, the number of measurements performed was not mentioned. Was it a mean of three measurements or mean of nine measurements, as recommended by the manufacturer for this UP (PachPen; Accutome Inc, Malvern, PA)?

Indian Journal of Ophthalmology, 2019

Why some 10 years after investing heavily in the technique of laboratory expanded corneal epithel... more Why some 10 years after investing heavily in the technique of laboratory expanded corneal epithelial cells for the treatment of limbal stem cell deficiency (LSCD) did the group of Virender Singh Sangwan (VSS) apparently turn their back on this and started using small explants of the cornea to treat LSCD? This technique of using small limbal explants was called "SLET or simple limbal epithelial transplantation." The technique of cultivated limbal epithelial stem cell transplantation (CLET) works quite well in those groups who have established it. However, the bottom line is that despite some 17 years of its use with reasonably good success by all groups involved, it fails one critical test: it fails to reach a large number of patients because it requires a high level of infrastructure investment. To culture autologous corneal cells requires highly trained specialist cell culture staff working in dedicated premises under highly regulated conditions that meet the standard of the local regulatory authority. As such, it is beyond the reach of the majority of ophthalmic surgeons and patients suffering from LSCD who could benefit from it.

Hunter's Point South Waterfront Park, 2018

This investigation was conducted as part of the Landscape Architecture Foundation's 2018 Case Stu... more This investigation was conducted as part of the Landscape Architecture Foundation's 2018 Case Study Investigation (CSI) program. CSI matches faculty-student research teams with design practitioners to document the benefits of exemplary high-performing landscape projects. Teams develop methods to quantify environmental, economic and social benefits and produce Case Study Briefs for LAF's Landscape Performance Series.

International Journal of Public Health

Many reviews have been conducted on the economic evaluation of the HPV vaccine in global north co... more Many reviews have been conducted on the economic evaluation of the HPV vaccine in global north countries. But there is a dearth of such reviews in the Global South countries. Hence, this systematic review aims to summarize studies done in these countries. Four databases PubMed, Embase, Cochrane Library, and Google Scholar from 2009 to 2019 were searched for economic evaluations on HPV vaccination in the Global South countries. PRISMA guidelines were followed to include full-text articles. 40 original articles were shortlisted for full-text review. Studies had varied models, assumptions, and results according to different scenarios. Most studies concluded HPV vaccination to be cost-effective under varied scenarios and vaccine cost was the most influential parameter affecting the sensitivity analyses, consequently incremental cost-effectiveness ratio. A wide range in the cost-effectiveness ratio was observed in the included studies due to different study settings, populations, and inconsistencies in modeling practices (variations in methodological approaches). This review suggests the introduction of HPV vaccination alone or in combination with screening according to different countries. The price of the vaccine should be economical and funds for the vaccine should be provided by public sector firms.

Chemical Biology & Drug Design, 2016

Benzylidene indanones have been designed and synthesized from gallic acid, a plant phenolic acid ... more Benzylidene indanones have been designed and synthesized from gallic acid, a plant phenolic acid as possible anticancer agent. The best analogue of the series, that is, 3-(3',4',5'-trimethoxyphenyl)-4,5,6-trimethoxy-2-(4˝-nitrobenzylidene)-indan-1-one (8) exhibited potent cytotoxicity (IC50 =3-10 μm) against several human cancer cell lines through microtubule destabilization (IC50 =1.54 μm) after occupying colchicine-binding site of β-tubulin. In cell cycle analysis, compound 8 exerted G2/M phase arrest in both MCF-7 and MDA-MB-231 cells and induced apoptosis. It reduced 34.8% solid tumor in in vivo Ehrlich ascite carcinoma in Swiss albino mice at 30 mg/kg dose. In acute oral toxicity experiment, it was tolerable up to 300 mg/kg doses in Swiss albino mice. The lead compound 8 needs to be optimized for better activity.

Corporations today bear a significant portion of an employee’s health care costs and play a proac... more Corporations today bear a significant portion of an employee’s health care costs and play a proactive role in their wellness care. Telewellness care leverages today’s technological ability to electronically exchange data, voice, video, and other types of information to deliver such care when the provider and the recipient are geographically separated. Corporations are adopting telewellness care to reduce costs and improve effectiveness.

West Point Foundry Preserve, Phase 1