152 results on '"Satyaki Ganguly"'
Search Results
52. Penicillamine-Induced Stevensjohnson Syndrome–Toxic Epidermal Necrolysis (Sjs–Ten) Overlap In An Hiv-Infected Patient With Wilson’s Disease And Hepatitis B
- Author
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Namrata Chhabra, P. S. Meghana Reddy, Ayush Bhatnagar, and Satyaki Ganguly
- Subjects
Pharmacology ,Pharmacology (medical) ,Toxicology - Abstract
Introduction: Stevens-Johnson syndrome (SJS) and Toxic epidermal necrolysis (TEN) are severe adverse drug reactions characterized by widespread blistering and mucositis. Wilson’s disease is a rare, autosomal recessive disorder that results in excessive copper accumulation in the body, where penicillamine is an effective treatment option for copper chelation. Penicillamine-induced SJS-TEN is a rare but potentially fatal adverse effect. There is increased susceptibility to SJS/TEN in HIV infection due to immunosuppression and chronic liver disease due to impaired hepatic function. Objective: To diagnose and manage the occurrence of the rare severe adverse cutaneous drug reactions in the backdrop of immunosuppression and chronic liver disease. Methodology: A case report CASE REPORT: We are reporting penicillamine-induced SJS-TEN overlap in a 30-year-old male with Wilson’s disease, HIV and Hepatitis B who was treated with intravenous immunoglobulins. The patient later developed a neurotrophic ulcer in the right cornea as a delayed sequela. Conclusion: Our case report emphasizes that there is an increased predisposition to SJS/TEN in immunocompromised and chronic liver disease patients. Physicians should be well aware of the potential danger of SJS/TEN in this subset of patients, even while prescribing a relatively safer drug.
- Published
- 2023
53. Improvements to the Analytical Model to Describe UIS Events
- Author
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Philipp Steinmann, Satyaki Ganguly, Brett Hull, Khiem Lam, Daniel J. Lichtenwalner, Jae-Hyung Park, Rahul Potera, Jim Richmond, Sei-Hyung Ryu, Shadi Sabri, Charles Van Brackle, Edward Van Brunt, and Elizabeth Williams
- Subjects
Electrical and Electronic Engineering ,Electronic, Optical and Magnetic Materials - Published
- 2022
54. Improved X-Band Performance and Reliability of a GaN HEMT With Sunken Source Connected Field Plate Design
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Kyle M. Bothe, Satyaki Ganguly, Jia Guo, Yueying Liu, Alex Niyonzima, Olof Tornblad, Jeremy Fisher, Don A. Gajewski, Scott T. Sheppard, and Basim Noori
- Subjects
Electrical and Electronic Engineering ,Electronic, Optical and Magnetic Materials - Published
- 2022
55. Common, But Neglected: A Comprehensive Review of Leg Ulcers in Sickle Cell Disease
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Meenakshi Sinha, Henu Kumar Verma, Tarun Sahu, Ramanjan Sinha, and Satyaki Ganguly
- Subjects
Advanced and Specialized Nursing ,Wound Healing ,medicine.medical_specialty ,Web of science ,business.industry ,Data synthesis ,Leg Ulcer ,MEDLINE ,Treatment options ,Anemia, Sickle Cell ,Dermatology ,Disease ,Leg ulcer ,Data extraction ,Quality of Life ,medicine ,Humans ,Intensive care medicine ,business - Abstract
OBJECTIVE To compile available evidence to better understand the management of leg ulcers in sickle cell disease (SCD), as well as describe potential therapeutic steps that may be required to improve the quality of life of patients with SCD leg ulcers. DATA SOURCES MEDLINE, PubMed, EMBASE, and Web of Science databases. STUDY SELECTION A comprehensive search was conducted to retrieve relevant studies using the keywords "sickle cell disease and leg ulcer," "ulcer treatments, diagnosis and sickle cell," and "wound sickle cell." Studies published through July 2020 were included. DATA EXTRACTION Two independent authors selected all studies that assessed the relationship between leg ulcer and SCD identified from online databases. DATA SYNTHESIS The authors have summarized updated information on pathophysiology (vasculopathy linked to chronic hemolysis and endothelial dysfunction), diagnosis, and available treatment options to unravel the dermohematologic connection between leg ulcers and SCD. CONCLUSIONS It is the authors' hope that this detailed discussion of the information available on leg ulcers and SCD will lead to a better appreciation of this clinical problem by the clinicians and researchers and in turn have a long-term positive effect on the quality of life of patients with SCD. Researchers should design new trials considering these insights and potential therapeutic approaches based on current knowledge.
- Published
- 2021
56. Rare Co-Existent Dermatitis Herpetiformis and Psoriasis in a Child: A Causal Relationship?
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Ajeet Singh, Satyaki Ganguly, Namrata Chhabra, and Vandita Singh
- Subjects
General Engineering - Published
- 2022
57. P383 ‘It's not Fungus, its Nocardia’—an elementary diagnostic challenge for draining sinus on abdominal wall (rare): a case report
- Author
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Richa Anjleen Tigga, Archana Y Keche, Satyaki Ganguly, and Anjali Chand
- Subjects
Infectious Diseases ,General Medicine - Abstract
Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Introduction A rare finding of abdominal wall clinical presentation of persistent progressive tumefaction with draining sinus with no granules caused by Nocardia brasiliensis. Methods History: A 22-year-old presented to the Dermatology OPD with complaints of swelling and tenderness and discharging sinuses with no granules around the periumbilical region in the lower abdominal area for three years. His initial fine needle aspiration cytology specimen report was inconclusive. He received anti-Kochs treatment based on a positive Montoux test and family history from outside the hospital. Initially punch biopsy samples were sent for fungal processing to our laboratory which was inconclusive. Repeat pus aspirate and punch biopsy samples were subjected to conventional techniques. The sample was inoculated on Sabouraud's Dextrose agar, Brain heart Infusion agar, and Lowenstein-Jensen media. Direct Smear was subjected to Gram stain and Modified Zeihl Neelson stain with 1% Sulfuric acid as decoloriser. Results Conclusion
- Published
- 2022
58. P216 Rare isolates from subcutaneous mycotic lesions; A study from tertiary care center in Chhattisgarh, India
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Keche, Archana, primary, Tigga, Richa, additional, Satyaki, Ganguly, additional, Chhabra, Namrata, additional, and Gupta, Rakesh, additional
- Published
- 2022
- Full Text
- View/download PDF
59. Severe Pancytopenia Following Single Dose Methotrexate In Psoriasis: A Rare And Potentially Lethal Manifestation
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Vinay Rathore, Namrata Chhabra, Ritul Choudhary, Satyaki Ganguly, and Ajeet Singh
- Subjects
Pharmacology ,medicine.medical_specialty ,Side effect ,business.industry ,Toxicology ,medicine.disease ,Pancytopenia ,Dermatology ,Nephropathy ,Granulocyte colony-stimulating factor ,Psoriasis ,medicine ,Pharmacology (medical) ,Platelet ,Methotrexate ,Sex organ ,business ,medicine.drug - Abstract
Methotrexate is an anti-metabolite, anti-cancer drug frequently used in the treatment of extensive chronic plaque psoriasis. Psoriatic plaque erosion is a rare toxic side effect of single-dose methotrexate and is described as a sign of impending pancytopenia. Here, we report a case of a 48- year-old male presented with multiple oral and genital erosions, accompanied by fissuring over palm and soles for 5 days. His laboratory tests revealed severe pancytopenia and nephropathy. He had a history of chronic plaque psoriasis for which he took a single dose of 15 mg methotrexate. During the hospital stay, the patient needed folate antagonist, granulocyte colony-stimulating factor (G-CSF), intravenous fluids, blood transfusions, and platelet transfusions. He recovered within 12 days of admission.
- Published
- 2021
60. Psoriasis management during the COVID-19 pandemic: Recommendations by SIG psoriasis (IADVL Academy)
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Abir Saraswat, Satyaki Ganguly, Parimalam Kumar, Haritha Komeravalli, Anchala Parthasaradhi, Sandeep Arora, Vinay Kumar Singh, Jayakar Thomas, and Shekhar N Pradhan
- Subjects
Microbiology (medical) ,2019-20 coronavirus outbreak ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,MEDLINE ,Dermatology ,lcsh:RL1-803 ,Therapeutic Guidelines ,medicine.disease ,Infectious Diseases ,Psoriasis ,Pandemic ,lcsh:Dermatology ,Immunology and Allergy ,Medicine ,business ,Intensive care medicine - Published
- 2021
61. Post-COVID-19 biologically false-positive VDRL: A report
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Ghazal, Ahmed, Anju, George C, and Satyaki, Ganguly
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COVID-19 ,Humans ,False Positive Reactions ,Syphilis ,Treponema pallidum ,Syphilis Serodiagnosis - Published
- 2022
62. Development of severe pemphigus vulgaris following ChAdOx1 nCoV-19 vaccination and review of literature
- Author
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Ajeet Singh, Sujana J. Bharadwaj, Anju G. Chirayath, and Satyaki Ganguly
- Subjects
Adult ,Male ,ChAdOx1 nCoV-19 ,Vaccination ,COVID-19 ,Humans ,Dermatology ,Pemphigus - Abstract
Vaccines are indeed a boon for tackling the present COVID-19 pandemic. In India, ChAdOx1 nCoV-19 (Covishield) is the most commonly used vaccine in the government vaccination program for adults more than 18 years of age. It is a recombinant vaccine developed by Oxford-Astra Zeneca and manufactured in India by Serum Institute of India (SSI). Here, we report a case of severe pemphigus vulgaris following the second dose of ChAdOx1 nCoV-19 vaccination in an adult male. The patient developed septicemia during the course of hospital stay, and he was managed with systemic steroids, parenteral antibiotics, and intravenous immunoglobulins (IVIg) along with proper wound care. Patient started improving within 1 month of therapy. This case is being reported in view of the rarity of pemphigus vulgaris following ChAdOx1 nCoV-19 vaccine.
- Published
- 2022
63. Accelerated Testing of SiC Power Devices under High-Field Operating Conditions
- Author
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Sei Hyung Ryu, Scott Allen, Edward Van Brunt, John W. Palmour, Jae Hyung Park, Daniel J. Lichtenwalner, Donald A. Gajewski, Shadi Sabri, Philipp Steinmann, Brett Hull, Satyaki Ganguly, Amy Romero, and Jim Richmond
- Subjects
010302 applied physics ,Materials science ,Mechanical Engineering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Engineering physics ,Mechanics of Materials ,0103 physical sciences ,MOSFET ,General Materials Science ,Power semiconductor device ,High field ,0210 nano-technology - Abstract
Power metal-oxide-semiconductor field-effect transistors (MOSFETs) experience conditions of high field during normal operation. During switching conditions, unexpected transient events may occur which force devices into avalanche or short circuit conditions. Moreover, silicon carbide devices typically experience higher fields in the gate oxide and drift regions than comparable Si devices due to channel and drift property differences. A summary of SiC MOSFET reliability and ruggedness test results are reported here. Reliability tests under high field conditions: positive-bias and negative-bias temperature instability (PBTI, NBTI) to examine threshold stability; time-dependent dielectric breakdown (TDDB) for gate oxide lifetime extrapolation; high-temperature reverse bias (HTRB); and HTRB testing under high neutron flux to determine terrestrial neutron single-event burnout (SEB) rates. High-power ruggedness evaluation is presented for SiC MOSFETs under forced avalanche conditions (unclamped inductive switching (UIS)) and under short-circuit operation to bound device safe operating areas. Overall results demonstrate the intrinsic reliability of SiC MOSFETs.
- Published
- 2020
64. Gentian violet: Revisited
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Satyaki Ganguly, Neel Prabha, Namrata Chhabra, and Ripu Daman Arora
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business.industry ,Administration, Topical ,MEDLINE ,Dermatology ,Drug resistance ,Pharmacology ,lcsh:RL1-803 ,Skin Diseases ,Infectious Diseases ,Drug Resistance, Bacterial ,Anti-Infective Agents, Local ,lcsh:Dermatology ,Animals ,Humans ,Medicine ,Gentian Violet ,business ,Anti-Infective Agents - Published
- 2020
65. Systemic Allergic Contact Dermatitis Post Inactivated COVID-19 Vaccine
- Author
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Ajeet Singh, JemshiS Rahim, and Satyaki Ganguly
- Subjects
Microbiology (medical) ,Infectious Diseases ,Immunology and Allergy ,Dermatology - Published
- 2022
66. Role of autoerythrocyte sensitization test in the diagnosis of recurrent spontaneous bruising
- Author
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Ajeet Singh, Praveen Kumar, Neel Prabha, Satyaki Ganguly, and Mayur Dudhe
- Subjects
Microbiology (medical) ,Infectious Diseases ,Immunology and Allergy ,Dermatology - Published
- 2023
67. The ‘rat-bitten ear’: a rare case of multifocal ulcerated lupus panniculitis
- Author
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Ghazal Ahmed, Anju George C, JemshiS Raim, and Satyaki Ganguly
- Subjects
Dermatology - Published
- 2023
68. Atrophic Lingual Plaque in Father-Son Duo
- Author
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Ghazal Ahmed, Satyaki Ganguly, and Soumil Khare
- Subjects
Microbiology (medical) ,Infectious Diseases ,Immunology and Allergy ,Dermatology - Published
- 2021
69. Localized scabies crustose over the engrafted skin: Report of two cases
- Author
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Ghazal Ahmed, Anju George C, Jemshi S. Rahim, and Satyaki Ganguly
- Subjects
Dermatology - Published
- 2022
70. Acquired Speckled Acrofacial Hypomelanosis: A Novel Presentation of an Existing Dermatosis
- Author
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Ritul Choudhary, Ajeet Singh, Satyaki Ganguly, and Vandita Singh
- Subjects
Microbiology (medical) ,Infectious Diseases ,Immunology and Allergy ,Dermatology - Published
- 2021
71. Coronavirus disease 2019 vaccination in patients with psoriasis: A position statement from India by SIG psoriasis (IADVL Academy)
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Anchala Parthasaradhi, Satyaki Ganguly, Bikash Ranjan Kar, Jayakar Thomas, Shekhar Neema, Sushil Tahiliani, Dharshini Sathishkumar, Shrichand G Parasramani, K Venkata Chalam, and Haritha Komeravalli
- Subjects
Vaccines ,Infectious Diseases ,COVID-19 Vaccines ,SARS-CoV-2 ,Vaccination ,COVID-19 ,Humans ,India ,Psoriasis ,Dermatology - Abstract
Coronavirus disease 2019 (COVID-19) pandemic has affected every sphere of life including management of psoriasis. The availability of COVID-19 vaccines has given rise to hope and at the same time some apprehensions as well. With the general population becoming eligible for vaccination, there is some confusion, on the eligibility of patients with different medical conditions and patients on immunosuppressive or immunomodulating medications for COVID-19 vaccination. Dermatologists treating psoriasis patients frequently face questions from them, whether they can undergo coronavirus disease 2019 vaccination. A PUBMED search was performed using the following strategy: ‘COVID-19’ AND ‘Vaccine’ AND ‘Psoriasis’. We also performed a PUBMED search using the following strategy: ‘SARS-CoV-2’ AND ‘Vaccine’ AND ‘Psoriasis’. All articles irrespective of language and publication date were included to arrive at this position statement. This position statement deals with the safety, eligibility and modifications of treatment, if needed among psoriasis patients with regards to the coronavirus disease 2019 vaccines currently available in India.
- Published
- 2021
72. Palatal perforation in a patient with borderline lepromatous leprosy: leprosy still not eradicated
- Author
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Preetha Anand, Sujana Bharadwaj, Satyaki Ganguly, and Santhosh Rao
- Subjects
Leprosy, Lepromatous ,Leprosy ,Leprosy, Multibacillary ,Prevalence ,Humans ,India ,Leprosy, Borderline ,Female ,General Medicine - Abstract
Leprosy was eliminated globally in 2000, but it continues to be endemic in developing countries like India, Brazil and Indonesia, with a prevalence of 0.57/10 000 persons in India (2020). At the end of the year 2020, the prevalence was 129 389, and oral manifestation of the leprosy is luncommon. We hereby report a case of a female patient in her late 30s who presented with palatal perforation. Following a thorough history taking and full body clinical examination, we arrived at a diagnosis of leprosy, and prompt treatment was initiated. Knowledge of cases like this becomes important as the oral lesion is said to form an essential source of leprosy dissemination in the community, and awareness about them becomes crucial, demanding immediate attention.
- Published
- 2022
73. Grade 2 disability among leprosy patients: A pilot study from an endemic area of Central India
- Author
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Satyaki Ganguly, Bada Shravani, ArvindK Shukla, Namrata Chhabra, Neel Prabha, Divya Sachdev, and Soumil Khare
- Abstract
Deformities and disabilities in leprosy lead to significant morbidity to the individual and financial burden to the family. As the prevalence of leprosy is higher in central India, this study was conducted to know the burden of deformity and disability among leprosy patients in central India and the factors associated with it.This was a hospital-based, cross-sectional study, conducted on 50 new or on treatment or released from treatment leprosy patients, attending the Dermatology OPD of a tertiary care institute in Central India. Disability was graded as per the WHO criteria for disability grading of hands and feet.Grade 2 disability was found among 32% of the patients with leprosy, whereas a total of 60% of our patients had either grade 1 or grade 2 disabilities. Trophic ulcer was found among 20% and claw hand among 14% of leprosy patients. We found significant associations of lepromatous leprosy with trophic ulcer (p = 0.004) and grade 2 disability (p = 0.012). All patients with claw hands and 80% of the patients with trophic ulcers presented to the healthcare facility at least 6 months after the onset of symptoms.We found very high rates of disability and deformity among leprosy patients indicating possible huge burden of morbidity among leprosy patients in central India. The significant association of lepromatous leprosy with trophic ulcer and grade 2 disability indicated delayed presentation and diagnosis of lepromatous leprosy patients. Our results underlined the need for large scale community-based studies on disability and deformity among leprosy patients in Central India. These results also call for better training of primary level healthcare workers for early detection and management of deformities and disabilities as well as better patient education for leprosy patients regarding hand and foot care.
- Published
- 2021
74. SkIndia Quiz: An Elderly Woman with Persistent and Painful Genital Erosion
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Ghazal Ahmed, Satyaki Ganguly, CAnju George, and JemshiS Rahim
- Published
- 2021
75. Gate Oxide Reliability of SiC MOSFETs and Capacitors Fabricated on 150mm Wafers
- Author
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Scott Allen, John W. Palmour, Donald A. Gajewski, Brett Hull, Edward Van Brunt, Shadi Sabri, Satyaki Ganguly, and Daniel J. Lichtenwalner
- Subjects
Materials science ,business.industry ,Mechanical Engineering ,Time-dependent gate oxide breakdown ,Condensed Matter Physics ,law.invention ,chemistry.chemical_compound ,Capacitor ,Reliability (semiconductor) ,chemistry ,Mechanics of Materials ,law ,Gate oxide ,MOSFET ,Silicon carbide ,Optoelectronics ,General Materials Science ,Wafer ,business - Abstract
Gate oxide reliability on silicon carbide MOSFETs and large-area SiC N-type capacitors was studied for devices fabricated on 150mm SiC substrates. Oxide lifetime was measured under accelerated stress conditions using constant-voltage time-dependent dielectric breakdown (TDDB) testing, or ramped-voltage breakdown (RBD) testing. TDDB results from 1200V Gen3 MOSFETs reveal a field acceleration parameter of about 35 nm/V, similar to values reported for SiO2 on silicon. Temperature-dependent RBD tests of large capacitors from 25°C to 200°C reveal an apparent activation energy of 0.24eV, indicating that oxide lifetime increases as the temperature is decreased, as expected. Using this acceleration parameter and activation energy in the linear field model, the gate oxide lifetime from MOSFET TDDB testing extrapolates to greater than 108 hours at a gate voltage of 15 VGS at 175°C.
- Published
- 2019
76. Avalanche Ruggedness Characterization of 10 kV 4H-SiC MOSFETs
- Author
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Edward Van Brunt, Subhashish Bhattacharya, Sanket Parashar, Victor Veliadis, Ashish Kumar, Satyaki Ganguly, and Shadi Sabri
- Subjects
Materials science ,Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Condensed Matter Physics ,Engineering physics ,Characterization (materials science) - Abstract
In this paper, single pulse unclamped inductive switching (UIS) test of Wolfspeed Gen-3 10 kV, 15 A 4H-SiC MOSFETs is performed for four operating conditions at room temperature. The avalanche energy is observed to be around 7.0 J. The measured values are in good agreement with expected behavior, which may be extrapolated beyond the experimentally measured range. Failure analysis was conducted after each device failure to observe the failure locations. Avalanche parameters of SiC MOSFETs with various voltage ratings are compared. The avalanche energy of the Gen-3 10 kV, 15 A 4H-SiC MOSFETs is obtained to be superior to earlier generations of 10 kV SiC MOSFETs.
- Published
- 2019
77. An instance of excellent response of subcutaneous zygomycosis to itraconazole monotherapy
- Author
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Padma Das, Divya Sachdev, Satyaki Ganguly, Nitinkumar Borkar, Nighat Hussain, and Priyadarshini Patro
- Subjects
Surgical resection ,Fungal infection ,medicine.medical_specialty ,Itraconazole ,Case Report ,Microbiology ,Basidiobolus ranarum ,Itraconazole therapy ,Medicine ,Spindle Cell Tumor ,lcsh:QH301-705.5 ,lcsh:R5-920 ,biology ,Subcutaneous zygomycosis ,business.industry ,biology.organism_classification ,Subcutaneous swelling ,Surgery ,Infectious Diseases ,lcsh:Biology (General) ,Spindle cell tumor ,Right upper arm ,business ,lcsh:Medicine (General) ,medicine.drug - Abstract
Subcutaneous zygomycosis is a rare fungal infection caused by Basidiobolus ranarum. This entity is usually endemic in South India and only limited numbers of cases have been reported from central India. We report a case of 4-year-old male child from Chhattisgarh, who presented with a painless, non-tender, large, subcutaneous swelling of 4 months duration on the right upper arm, which was initially misdiagnosed as benign spindle cell tumor and advised surgical resection. But the fungal culture of the affected tissue grown Basidiobolus ranarum and the child responded very well to itraconazole therapy only. Keywords: Basidiobolus ranarum, Subcutaneous zygomycosis, Fungal infection, Spindle cell tumor, Itraconazole therapy
- Published
- 2019
78. Progressive Symmetric Erythrokeratodermia with Overlying Psoriasis as Wolf's Isotopic Phenomenon: A Case Report
- Author
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Ghazal Ahmed, Satyaki Ganguly, Ritul Choudhary, and CAnju George
- Published
- 2021
79. Systemic Management of Psoriasis Patients in Indian Scenario: An Expert Consensus
- Author
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Bikash Ranjan Kar, Sunil Dogra, Nina Madnani, Krina B Patel, Satyaki Ganguly, Abhishek De, Sushil Tahiliani, Manas Chatterjee, Murlidhar Rajagopalan, Shekhar Neema, and Shrichand G Parasramani
- Subjects
medicine.medical_specialty ,Modalities ,business.industry ,Consensus Statement ,Expert consensus ,Disease ,psoriasis ,Biologics ,systemic ,medicine.disease ,Biologic Agents ,Indian scenario ,Quality of life (healthcare) ,Psoriasis ,Indian consensus ,Medicine ,Dosing ,business ,Intensive care medicine ,conventional - Abstract
Background: Psoriasis is a common inflammatory disease with significant comorbidities, and regardless of its extent, it affects the patients' quality of life. The various modalities of treating psoriasis comprise topical or systemic medications, phototherapy, and an array of biologic agents. There is a lack of Indian recommendations on the management of psoriasis with these different modalities and challenges faced by the clinicians in day-to-day practice. Aim: To develop India-specific consensus for systemic management of patients with moderate-to-severe psoriasis. Method and Results: A panel of dermatology experts, based on the evidence and international recommendations, coupled with their own clinical experience, developed recommendations for systemic management of patients with moderate-to-severe psoriasis. Conclusion: These recommendations are meant to provide guidance in terms of choice of systemic therapies, dosing, effectiveness, and safety. It also addresses clinical challenges that may be experienced during psoriasis management.
- Published
- 2021
80. Letter to the Editor
- Author
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Ghazal Ahmed, Anju George C, and Satyaki Ganguly
- Subjects
Infectious Diseases ,Public Health, Environmental and Occupational Health ,Pharmacology (medical) ,Dermatology - Published
- 2022
81. Accelerated Testing of SiC Power Devices
- Author
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Scott Allen, Philipp Steinmann, Daniel J. Lichtenwalner, Donald A. Gajewski, Amy Romero, Edward Van Brunt, Brett Hull, Sei-Hyung Ryu, Shadi Sabri, Satyaki Ganguly, and John W. Palmour
- Subjects
Materials science ,Dielectric strength ,business.industry ,Transistor ,Time-dependent gate oxide breakdown ,law.invention ,chemistry.chemical_compound ,Reliability (semiconductor) ,chemistry ,Gate oxide ,law ,MOSFET ,Silicon carbide ,Optoelectronics ,Power semiconductor device ,business - Abstract
Power metal-oxide-semiconductor field-effect transistors (MOSFETs) experience conditions of high field during normal operation. During switching conditions, unexpected transient events may occur which force devices into avalanche or short circuit conditions. Moreover, silicon carbide devices typically experience higher fields in the gate oxide and drift regions than comparable Si devices due to channel and drift property differences. A summary of 4H-SiC MOSFET reliability and ruggedness test results are reported here. Reliability tests under high field conditions: positive-bias and negative-bias temperature instability (PBTI, NBTI) to examine threshold stability; time-dependent dielectric breakdown (TDDB) for gate oxide lifetime extrapolation; high-temperature reverse bias (HTRB); and HTRB testing under high neutron flux to determine terrestrial neutron single-event burnout (SEB) rates. High-power ruggedness evaluation is presented for SiC MOSFETs under forced avalanche conditions (unclamped inductive switching (UIS)) and under short-circuit operation to bound device safe operating areas. Overall results demonstrate the intrinsic reliability of SiC MOSFETs.
- Published
- 2020
82. Cutaneous manifestations associated with COVID-19 in children: A systematic review
- Author
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Kiran Akhade, Seema Shah, Eli Mohapatra, Rachita Nanda, Satyaki Ganguly, and Anil Kumar Goel
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,Chilblain ,business.industry ,cutaneous ,COVID-19 ,030209 endocrinology & metabolism ,Review Article ,medicine.disease ,Dermatology ,Coronavirus ,03 medical and health sciences ,0302 clinical medicine ,children ,Skin biopsy ,Mycoplasma pneumonia ,medicine ,Etiology ,Maculopapular Lesion ,Kawasaki disease ,030212 general & internal medicine ,Erythema multiforme ,Chilblains ,business ,Exanthem - Abstract
Background: Cutaneous manifestation of COVID 19 in children has not yet been reviewed systematically and hence this review gives a future direction to the clinicians to be vigilant for skin presentations during such pandemic.Methodology: The review was done as per the guidelines of PRISMA and literature search was done on PubMed database using keywords as COVID-19, children and skin in different combinations. Articles published in English with cases of age 1 month to 18 years were eligible. The outcome included varied aspects of cutaneous and COVID-19 infection. The review protocol was not registered.Results: Of 51 publications identified, 13 studies containing 149 children met the eligibility criteria. Acrally located erythematous maculopapular lesion was the most common finding in 138 children. Erythema multiforme, varicella like exanthem and Kawasaki disease like presentations were reported in the rest of the cases. The duration of the skin lesion was 1-2 weeks in 43%. Skin biopsy done in 18 cases revealed superficial & deep perivascular and peri-eccrine lymphocytic infiltrate & lymphocytic vasculitis. RT-PCR was positive in 13.8% cases. Serological markers for HSV, parvovirus B19 analyzed across various studies, were found negative, except for mycoplasma pneumoniae in 2 of 20 cases tested.Discussion: Clinicopathologic analysis established chilblains like lesion in 43% cases with no confirmed etiology like cold exposure, autoimmune dysfunction, drug reaction, or viral infection. The usual cephalo-caudal spread of a viral exanthem was also missing. However, a low number of discussed cases was a limitation of the study.Conclusion: In the absence of any confirmed etiology for such cutaneous manifestations, the possibility of COVID-19 should be explored and evaluated thoroughly during such pandemic.
- Published
- 2020
83. A Case Report of Werner’s Syndrome With a Novel Mutation From India
- Author
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Ajeet Singh, Satyaki Ganguly, Hitesh Yadav, Junko Oshima, and Namrata Chhabra
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Premature aging ,Infertility ,congenital, hereditary, and neonatal diseases and abnormalities ,DNA repair ,Disease ,Dermatology ,030204 cardiovascular system & hematology ,03 medical and health sciences ,Exon ,0302 clinical medicine ,Genetics ,Medicine ,Werner's syndrome ,Werner syndrome ,wrn gene ,Progeria ,business.industry ,aging ,General Engineering ,nutritional and metabolic diseases ,progeria ,medicine.disease ,Miscellaneous ,werner syndrome ,novel mutation ,business ,030217 neurology & neurosurgery - Abstract
Werner's syndrome (WS) or progeria adultorum is a heritable autosomal recessive disease in which the aging process is accelerated, just after puberty. It is caused by mutations in the WRN gene, which encodes a member of the RECQ family of DNA helicases and has a role in DNA repair. WS is being more appropriately recognized as a condition in which the lack of WRN protein results in an overall decline in the normal physiological functions of various organs rather than premature aging. Here, we describe a rare case of WS with a novel mutation from India. Our patient was an adult male with a history of growth arrest since puberty and other clinical features such as sclerodermatous skin changes, premature graying and thinning of hair, bilateral cataract, a single non-healing ulcer, hypothyroidism, underdeveloped secondary sexual characters with hypogonadism, infertility, squeaky voice, and early signs of arteriosclerosis. On genetic analysis, he was found to have a homozygous pathogenic variant c.3190C>T in exon 26 of the WRN gene, which has never been reported in WS.
- Published
- 2020
84. Multifocal cutaneous tuberculosis coexisting with pulmonary tuberculosis
- Author
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Satyaki Ganguly, AnjaliSrikanth Mannava, ChrisAlex Wesley Garapati, and KrantiChandan Jaykar
- Subjects
Microbiology (medical) ,Infectious Diseases - Published
- 2022
85. An analysis of interns' feedback after dermatology posting
- Author
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Satyaki, Ganguly, Kranti Chandan, Jaykar, Namrata, Chhabra, and Neel, Prabha
- Subjects
Dermatology - Abstract
Dermatology knowledge among fresh medical graduates is poor in India as undergraduate medical curriculum and Internship training lack adequate focus on this subject. This contributes to the inappropriate management of Dermatology patients by the medical graduates.To analyse the expectations, motivations and experience of interns during their dermatology posting.This was a retrospective record review of questionnaire-based anonymous validated feedback forms submitted by interns posted in a dermatology department of a tertiary care institute. The feedback form contained nine multiple choice questions some of which allowed multiple responses.A total of 63 completed forms were analysed. The common expectations before the posting were, to learn the management of basic dermatological problems (98.4%), to take an informed decision regarding post-graduation in dermatology (53.9%) and hope that the posting will be useful for the postgraduate entrance test (50.7%). After the posting, 69.87% of them felt that their expectations were fulfilled. After the posting, 84.1% of the interns felt that they would have liked to study dermatology as a separate undergraduate subject with a summative assessment at the end.The sample size was less and the feedback form contained limited questions.The majority of the interns were satisfied after dermatology posting. Increased exposure of interns to dermatology inpatients and side laboratory procedures will further enrich their clinical experience. The inclusion of dermatology as a separate subject with examination in the undergraduate curriculum was a felt need.
- Published
- 2022
86. Topical methotrexate 1% gel for the treatment of localized alopecia areata
- Author
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Satyaki Ganguly, Neel Prabha, Namrata Chhabra, Ghazal Ahmed, and Soumil Khare
- Subjects
medicine.medical_specialty ,Alopecia Areata ,business.industry ,Administration, Topical ,Dermatology ,Alopecia areata ,medicine.disease ,Methotrexate ,Treatment Outcome ,medicine ,Humans ,business ,Gels ,medicine.drug - Published
- 2019
87. A High Efficiency, Ka-Band, GaN-on-SiC MMIC with Low Compression
- Author
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Terry Alcorn, Dan Namishia, Jennifer Gao, Jim W. Milligan, Fabian Radulescu, Satyaki Ganguly, Kyle M. Bothe, Don A. Gajewski, Jeremy Fisher, Scott Sheppard, Bruce Schmukler, Jeffrey Barner, Evan Jones, and Chris Hardiman
- Subjects
Materials science ,business.industry ,Amplifier ,dBm ,Gallium nitride ,High-electron-mobility transistor ,Power (physics) ,chemistry.chemical_compound ,chemistry ,Silicon carbide ,Optoelectronics ,Ka band ,business ,Monolithic microwave integrated circuit - Abstract
The design and performance of a 28 V, 3-stage, Ka-band, GaN-on-SiC, power amplifier MMIC with high efficiency and low gain compression are presented. At 30 GHz, the MMIC provides saturated power of 37.6 dBm with an associated PAE of 39.8%. P1dB is within 1 dB of saturated power over the 26.5-30.5 GHz band. At 30 GHz, P1dB is 37.1 dBm with an associated PAE of 37.8%. In addition, the MMIC has a low quiescent bias of 72 mA.
- Published
- 2019
88. Reliability comparison of 28 V–50 V GaN-on-SiC S-band and X-band technologies
- Author
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Scott Sheppard, Jim W. Milligan, Satyaki Ganguly, Simon Wood, Jeff B. Barner, John W. Palmour, and Donald A. Gajewski
- Subjects
010302 applied physics ,Void (astronomy) ,Materials science ,business.industry ,020208 electrical & electronic engineering ,X band ,Failure rate ,02 engineering and technology ,High-electron-mobility transistor ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Optoelectronics ,S band ,Life test ,Electrical and Electronic Engineering ,Safety, Risk, Reliability and Quality ,business ,Ohmic contact ,Monolithic microwave integrated circuit - Abstract
This paper discusses the reliability performance of Wolfspeed GaN/AlGaN high electron mobility transistor (HEMT) MMIC released process technologies, fabricated on 100 mm high purity semi-insulating (HPSI) 4H-SiC substrates. The intrinsic reliability performances of the 28 V and 40 V technologies, with 400 nm and 250 nm gate length, have been characterized with DC accelerated life test (DC-ALT), for which ohmic contact inter-diffusion is the wear-out mechanism, and is accelerated by temperature and current. The intrinsic reliability performance of the 50 V technologies, with 400 nm gate length, have been characterized with RF-ALT, for which source-connected second field plate void coalescence is the wear-out mechanism which is accelerated by temperature. In spite of the differences in the accelerated test methodologies and wear-out mechanisms, all of the Wolfspeed GaN-on-SiC technologies demonstrate high and similar predicted lifetimes at their respective maximum recommended operating conditions. The reliability performance is supported with successful technology qualifications with zero failures, and volume manufacturing with a demonstrated low field failure rate.
- Published
- 2018
89. Pityriasis Rosea: Clinical Profile from Central India
- Author
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Neel Prabha, Namrata Chhabra, Satyaki Ganguly, and Sandeep S. Kulkarni
- Subjects
medicine.medical_specialty ,Erythema ,Epidemiology ,pityriasis rosea ,India ,Disease ,ECZEMATOUS SKIN LESIONS ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,HERALD PATCH ,lcsh:Dermatology ,Medicine ,Outpatient clinic ,030212 general & internal medicine ,integumentary system ,business.industry ,lcsh:RL1-803 ,medicine.disease ,Dermatology ,Clinical diagnosis ,Pityriasis rosea ,Original Article ,medicine.symptom ,business - Abstract
Background: Pityriasis rosea (PR) is a common, self-limiting dermatologic disorder. The information regarding the clinical profile of the disease in India is limited because of inadequate studies. Materials and Methods: A retrospective, record-based study on the clinical presentation of PR was conducted in a tertiary care center based in Central India. Data of all the patients presenting to our outpatient department from October 2014 to March 2015 with a clinical diagnosis of PR were analyzed. Results: The age of the patients ranged from 9 to 54 (mean-20.32) years. There was a male preponderance with a male-to-female ratio of 1.3:1. History of prodromal symptoms was present in 11 (27.5%) patients. Pruritus was a common symptom in 30 of 40 (75%) patients. Of 40 patients, 15 (35%) had herald patch. The morphology of skin lesions was typical in most of the patients (77.5%). Two (5%) patients had papular skin lesions, four (10%) patients had erythema multiforme-like skin lesions, and one patient each had papulovesicular, psoriasiform, and eczematous skin lesions. Conclusion: The clinical features of most of the cases were mostly in accordance with the classical pattern of PR, with few unusual features.
- Published
- 2018
90. Atypical cutaneous manifestations in lupus erythematosus: A report of three cases
- Author
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RemyaRaj Rajamohanan, SoumyaMary Koshy, Satyaki Ganguly, Anita Ramdas, and Sheela Kuruvila
- Published
- 2021
91. A study of community-associated methicillin-resistant Staphylococcus aureus in patients with pyoderma
- Author
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Sheela Kuruvila, Satyaki Ganguly, Sheela Devi, and Prasanth V Venniyil
- Subjects
Microbiology (medical) ,medicine.medical_specialty ,HA-MRSA ,medicine.drug_class ,CA-MRSA ,Staphylococcus ,Antibiotics ,Pyoderma ,furunculosis ,pyoderma ,Dermatology ,medicine.disease_cause ,Microbiology ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,lcsh:Dermatology ,Immunology and Allergy ,030212 general & internal medicine ,business.industry ,Public health ,biochemical phenomena, metabolism, and nutrition ,lcsh:RL1-803 ,medicine.disease ,bacterial infections and mycoses ,Methicillin-resistant Staphylococcus aureus ,Anterior nares ,Infectious Diseases ,medicine.anatomical_structure ,Nasal Swab ,Staphylococcus aureus ,Original Article ,business ,CA-MRSA, furunculosis, HA-MRSA, pyoderma, Staphylococcus - Abstract
Background: Health care–associated methicillin-resistant Staphylococcus aureus(HA-MRSA) are resistant to multiple antibiotics, therefore infections caused by them are difficult to treat resulting in high morbidity and mortality. While most of the research activities and public health initiatives are focused on HA-MRSA, the newly emerging pathogen, community-associated methicillin-resistant Staphylococcus aureus(CA-MRSA) is gaining in significance in respect to patient morbidity. There is a significant paucity of data regarding CA-MRSA in the developing parts of the world. Aim: To study the proportions of HA-MRSA and CA-MRSA infections among patients with culture-proven S. aureus infection and to find out how many of these patients showed presence of MRSA in nasal cultures of healthy contacts. Materials and Methods: Clinical details of 227 patients were recorded in the study, such as the duration and recurrence of the infection, history of antibiotic intake, and the presence of other medical illnesses. A pus swab was taken from each lesion and sent for culture and sensitivity. If the culture grew S. aureus, they were screened for methicillin resistance. A swab from the anterior nares of the healthy contact of each patient, whenever available, was collected and it was screened for MRSA. Results: Furunculosis was most common among the primary pyodermas (53/134; 39. 5%). Out of 239 pus culture samples obtained from 227 patients, 192 (84.58%) grew S. aureus; of these 150 (78.12%) were methicillin-sensitive S. aureus (MSSA), whereas 42 (21.98%) were MRSA. Out of the 42 MRSA isolated, 33 turned out to be CA-MRSA (78%) and 9 (22%) were HA-MRSA. Nasal swabs of healthy contacts of 34 MRSA patients were cultured. Out of them, two grew MRSA in the culture. Conclusion: The isolation rate of S. aureus was high in our study. Furthermore, our study, although hospital based, clearly indicated the substantial magnitude of the CA-MRSA problem in the local population.
- Published
- 2016
92. Firm, painless nodule over the cheek
- Author
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Satyaki Ganguly, Remya Rajamohanan, Reenu Mariam George, and Sheela Kuruvila
- Subjects
SkIndia Quiz ,medicine.anatomical_structure ,business.industry ,lcsh:Dermatology ,Medicine ,Nodule (medicine) ,Anatomy ,lcsh:RL1-803 ,Cheek ,medicine.symptom ,business - Published
- 2020
93. Misleading clinical presentation of a palmar lichen nitidus masquerading as pompholyx
- Author
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Ghazal Ahmed, Hitesh Yadav, and Satyaki Ganguly
- Subjects
Dorsum ,medicine.medical_specialty ,integumentary system ,Erythema ,business.industry ,Left little finger ,Dermatology ,medicine.disease ,Lichen nitidus ,Etiology ,Medicine ,Right palm ,Presentation (obstetrics) ,medicine.symptom ,skin and connective tissue diseases ,business - Abstract
Lichen nitidus is usually a chronic localized disease of unknown etiology having multiple differentials. A 10-year-old boy presented with itchy, multiple, discrete, grouped, and minute papules with surrounding erythema in some and exfoliation in few others, involving the center of the right palm, the palmar aspect of the left little finger with few lesions over the dorsal surface of both the hands. The presenting feature misguided us with a few clinical points which are unusual in lichen nitidus. We report the case to highlight the clinical mimicry and limitations of clinical assessment for diagnosing lichen nitidus.
- Published
- 2020
94. A comparative study of serum aminotransferases in chronic kidney disease with and without end-stage renal disease: Need for new reference ranges
- Author
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Lopamudra Ray, Satyaki Ganguly, Anirban Chatterjee, Rajlaxmi Sarangi, and Sunil Kumar Nanda
- Subjects
medicine.medical_specialty ,urologic and male genital diseases ,Gastroenterology ,End stage renal disease ,aspartate aminotransferase ,Liver enzyme ,Internal medicine ,medicine ,Renal osteodystrophy ,In patient ,Alanine aminotransferase ,end-stage renal disease ,medicine.diagnostic_test ,business.industry ,medicine.disease ,female genital diseases and pregnancy complications ,liver enzymes ,Endocrinology ,Alkaline phosphatase ,Original Article ,business ,Liver function tests ,alkaline phosphatase ,chronic kidney disease ,Kidney disease - Abstract
Background: Hepatic diseases are common among chronic kidney disease patients and liver function tests particularly serum liver enzymes play an important role in diagnosing and monitoring these patients. Serum aminotransferase levels commonly fall near the lower end of the range of the normal values in patients of chronic kidney disease (CKD). High-levels of serum alkaline phosphatase (ALP) can occur in these patients due to renal osteodystrophy. Thus, the recognition of liver damage in these patients is challenging. Aim: To compare the levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and ALP among three groups - CKD patients without end stage renal disease (ESRD), patients with ESRD and healthy controls. Materials and Methods: A retrospective, hospital-based study was carried out from 100 patients' records from each group and serum AST, ALT and ALP values were noted. Results: Our study showed that serum AST and ALT levels were significantly lower in CKD patients both without and with ESRD compared to controls. Further, these two enzyme levels were also significantly lower in CKD patients with ESRD compared to CKD patients without the condition. Serum ALP levels were significantly higher in patients with and without ESRD as compared to the controls. However, the values did not differ significantly between patients with and without ESRD. Conclusion: Levels of serum aminotransferases were low in CKD with and without ESRD and the levels become lower as the severity of CKD increases. Thus, the study established the need for separate reference ranges of serum aminotransferase in different stages of CKD.
- Published
- 2015
95. Oral isotretinoin as an adjunctive treatment for recurrent genital warts
- Author
-
Satyaki Ganguly, Sidharth Sonthalia, and Abhijeet Kumar Jha
- Subjects
Male ,medicine.medical_specialty ,Penile Diseases ,Administration, Oral ,Dermatology ,Administration, Cutaneous ,Genital warts ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Keratolytic Agents ,0302 clinical medicine ,Recurrence ,medicine ,Humans ,Isotretinoin ,Podophyllin ,business.industry ,Oral isotretinoin ,medicine.disease ,Condylomata Acuminata ,030220 oncology & carcinogenesis ,Adjunctive treatment ,Drug Therapy, Combination ,Dermatologic Agents ,business - Published
- 2018
96. Patch Test as a Diagnostic Tool in Hand Eczema
- Author
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Sheela Kuruvila, Satyaki Ganguly, and Natarajan Vigneshkarthik
- Subjects
Dermatology Section ,medicine.medical_specialty ,Allergy ,Clinical Biochemistry ,lcsh:Medicine ,medicine.disease_cause ,Atopy ,nickel ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Allergen ,Discoid eczema ,otorhinolaryngologic diseases ,medicine ,Allergic contact dermatitis ,potassium dichromate ,business.industry ,lcsh:R ,Patch test ,General Medicine ,medicine.disease ,Dermatology ,Hand eczema ,030220 oncology & carcinogenesis ,allergic contact dermatitis ,para- phenylenediamine ,business ,Contact dermatitis - Abstract
Introduction Allergic contact dermatitis is an important cause of hand eczema. Patch testing is the only investigation available to prove the diagnosis of allergic contact dermatitis. Exposures to allergens differ according to geographical, occupational, economic and social factors. Accordingly, patterns of allergic contact dermatitis differ in different parts of the world and different regions of the same country. Aim To study the causes of allergic contact dermatitis in adult patients with hand eczema with the help of patch testing. Materials and methods This was a cross-sectional study involving 54 hand eczema patients conducted between October 2013 and June 2015, at a tertiary care centre in Southern India. After a detailed history including history of occupational exposure and detailed examination, patch test was done on these patients with Indian standard series. The patches were removed after 48 hours. Another reading was taken after 72 hours. The readings were interpreted according to International Contact Dermatitis Research Group criteria and noted down. The data were summarized using mean and standard deviation for continuous variables and percentages for categorical and dichotomous variables. The test of association was done with Fisher's-exact test. Results Hyperkeratotic hand eczema was the commonest morphological type (29%), followed by discoid eczema. Pompholyx was significantly more common among patients with history of atopy. A total of 20 patients (37%) showed patch test positivity to a total of 25 allergens. Nickel was the most common allergen (11.11%) followed by para-phenylenediamine (PPD) (7.4%). Nickel (6 patients) and cobalt (3 patients) were the common allergens among women, while potassium dichromate (3 patients) and parthenium (2 patients) were the common allergens among men. Potassium dichromate allergy was significantly more common among masons and PPD allergy was significantly more common among hair dye users. Discoid pattern of hand eczema was common among patients with allergy to potassium dichromate. Conclusion Majority of the cases of hand eczema are not due to allergic contact dermatitis. History of atopy is common among patients with pompholyx. Allergic contact dermatitis due to nickel remains a common cause of hand eczema.
- Published
- 2016
97. Optical Fault Isolation and Nanoprobing Techniques for the 10 nm Technology Node and Beyond
- Author
-
Samia Rahman, Satyaki Ganguly, Martin von Haartman, Ahmad Umair, Jai Verma, and Tristan Deborde
- Subjects
business.industry ,Computer science ,Node (networking) ,business ,Fault detection and isolation ,Nanoprobing ,Computer network - Abstract
Resolution of optical fault isolation (FI) and nanoprobing tools needs to keep pace with the device downscaling to be effective for semiconductor process development. In this paper we present and discuss state-of-the-art FI and nanoprobing techniques evaluated on Intel test-chips fabricated on next generation process technology. Promising results were obtained but further improvements are necessary for the 7nm node and beyond.
- Published
- 2015
98. AlGaN/GaN HEMTs on Si by MBE with regrown contacts and f T = 153 GHz
- Author
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Mingda Zhu, Debdeep Jena, Satyaki Ganguly, Wan Sik Hwang, Jai Verma, Zongyang Hu, Huili Grace Xing, and Bo Song
- Subjects
Materials science ,business.industry ,Transistor ,Contact resistance ,Algan gan ,High-electron-mobility transistor ,Condensed Matter Physics ,law.invention ,law ,Optoelectronics ,Radio frequency ,business ,Ohmic contact ,Molecular beam ,Saturation (magnetic) - Abstract
AlGaN/GaN high-electron-mobility transistors (HEMT) have been grown by radio frequency molecular beam epi-taxy (RF-MBE) on 3″ Si substrates. A record low contact resistance Rc ˜ 0.11 Ω.mm has been achieved for GaN HEMTs on Si by using non alloyed ohmic contacts regrown by MBE. Owing to the low contact resistance a 75-nm gate length unpassivated HEMT shows intrinsic current gain cut-off frequency fT =153 GHz, a high saturation drain current density> 1.3 A/mm and a low RON of 1 Ω.mm, among the best reported for HEMTs on Si. With further scaling GaN HEMTs on Si can compete in the high-performance RF arena with similar devices on SiC, while exploiting the many advantages of integration with Si. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
- Published
- 2014
99. Coexistence of mucous membrane pemphigoid and vitiligo
- Author
-
Satyaki Ganguly, Sanath Aithal, and Sheela Kuruvila
- Subjects
vitiligo ,medicine.medical_specialty ,cicatricial pemphigoid ,Heterogeneous group ,integumentary system ,business.industry ,Case Report ,Vitiligo ,lcsh:RL1-803 ,Airway obstruction ,medicine.disease ,Dermatology ,Acquired autoimmune disorder ,ocular pemphigoid ,eye diseases ,Mucous membrane pemphigoid ,mucous membrane pemphigoid ,lcsh:Dermatology ,Medicine ,Ocular pemphigoid ,Cicatricial pemphigoid ,business ,skin and connective tissue diseases ,Autoimmune - Abstract
Mucous membrane pemphigoid describes a rare heterogeneous group of chronic, inflammatory, mucous membrane-dominated, subepithelial blistering diseases that manifest a varying constellation of oral, ocular, skin, genital, nasopharyngeal, esophageal, and laryngeal lesions. Life-threatening airway obstruction and sight-threatening ocular scarring can occur in this condition, which is rarely reported in Indian literature. Vitiligo is another acquired autoimmune disorder characterized by loss of melanocytes. Vitiligo is associated with a number of disorders also considered to be autoimmune. Here we report a very rare coexistence of MMP and vitiligo, the first such report from India.
- Published
- 2014
100. Dual Optical Marker Raman Characterization of Strained GaN-channels on AlN Using AlN/GaN/AlN Quantum Wells and 15N Isotopes
- Author
-
Zongyang Hu, Debdeep Jena, Bo Song, Xiaodong Yan, Pei Zhao, Meng Qi, Mingda Zhu, Guowang Li, Huili Grace Xing, Alexander Mintairov, Satyaki Ganguly, Vladimir Protasenko, and Jai Verma
- Subjects
Condensed Matter - Materials Science ,Materials science ,Physics and Astronomy (miscellaneous) ,Condensed Matter - Mesoscale and Nanoscale Physics ,business.industry ,Wide-bandgap semiconductor ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,Heterojunction ,Characterization (materials science) ,symbols.namesake ,Condensed Matter::Materials Science ,Vertical direction ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,symbols ,Semiconductor quantum wells ,Optoelectronics ,Raman spectroscopy ,business ,Quantum well - Abstract
This work shows that the combination of ultrathin highly strained GaN quantum wells embedded in an AlN matrix, with controlled isotopic concentrations of Nitrogen enables a dual marker method for Raman spectroscopy. By combining these techniques, we demonstrate the effectiveness in studying strain in the vertical direction. This technique will enable the precise probing of properties of buried active layers in heterostructures, and can be extended in the future to vertical devices such as those used for optical emitters, and for power electronics., 18 pages, 4 figures, published in Applied Physics Letters
- Published
- 2015
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