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1.
Malays Orthop J ; 18(1): 84-90, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38638651

ABSTRACT

Introduction: Peripheral nerve injuries (PNIs) remain an important health problem. PNIs mostly affect young men as this age group is mostly involved in road traffic accidents and other injuries at workplace. PNI can occur from foreign bodies like metal chips while working in industries using lathe machines. Among PNI's, injuries to the ulnar nerve, the brachial plexus and the median nerve are the most frequent lesions encountered. Materials and methods: This presentation is on a series of 18 cases of nerve injuries among industrial workers located from finger level up to the arm excluding the brachial plexus due to metallic foreign bodies entering while operating lathe machines over a period of two years with patients being followed-up over a one year period. Results: Mean age in this series was 31.3 years with age range 16-40 years and all were males. Two patients had more than one nerve involvement and one patient had associated vascular injury. All the patients showed functional improvement. Most common nerve injured was median nerve. Most common site for nerve injury was forearm. Combined lesions most commonly involved the ulnar and median nerves. Conclusion: Social cost of traumatic peripheral nerve injuries is significant since it has a higher incidence in young, previously healthy, and economically active people.

2.
Indian J Med Microbiol ; 47: 100490, 2024.
Article in English | MEDLINE | ID: mdl-37890412

ABSTRACT

BACKGROUND: Salivary shedding of SARS-CoV-2 is a known entity and its role has been established in transmission of the disease. The present study was performed to evaluate the duration of viral shedding in saliva in COVID-19 patients and its variation among symptomatic and asymptomatic patients with or without co-morbidities. METHODS: The present prospective observational study was conducted at the COVID-19 care hospital associated with primary to tertiary care in New Delhi, India. A total of 124 COVID-19 confirmed cases enrolled in two phases (January-March 2021; April-June 2021) who consented for 48hrly saliva and nasopharyngeal swab (NPS) specimens till discharge from the hospital for SARS-CoV-2 detection were included. The specimens obtained were tested for SARS-CoV-2 by Real-Time PCR. RESULTS: The sensitivity and the specificity of RT-PCR on saliva were 81.7 â€‹% and 85.0 â€‹%, respectively. The sensitivity of saliva-based PCR was comparable in symptomatic and asymptomatic patients (81.6 â€‹% vs 82.1 â€‹%). The sensitivity of saliva-based PCR markedly increased in the second phase of enrollment as compared to the first phase (92.6 â€‹% vs 78.5 â€‹%) indicating higher level of salivary shedding by the delta variant of SARS-CoV-2. The sensitivity of PCR on saliva was the highest up to day seven of illness. The median duration of RNA shedding in saliva was comparable among the symptomatic and asymptomatic patients. The severity of the disease was not associated with the duration of SARS-CoV-2 shedding in saliva. CONCLUSIONS: SARS-CoV-2 shedding in saliva continued till seven days in large number of patients including asymptomatic patients. Saliva is non-inferior to NPS specimen in the diagnosis of SARS-CoV-2. Saliva specimen is recommended as a good alternate to NPS for SARS-CoV-2 testing.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/diagnosis , COVID-19 Testing , Saliva , Reverse Transcriptase Polymerase Chain Reaction , Clinical Laboratory Techniques , RNA, Viral/genetics , RNA, Viral/analysis , Specimen Handling , Nasopharynx
3.
J Environ Radioact ; 262: 107146, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36898251

ABSTRACT

A systematic mapping of natural absorbed dose rate was carried out to assess the existing exposure situation in India. The mammoth nationwide survey covered the entire terrestrial region of the country comprising of 45127 sampling grids (grid size 36 km2) with more than 100,000 data points. The data was processed using Geographic Information System. This study is based on established national and international approaches to provide linkage with conventional geochemical mapping of soil. Majority (93%) of the absorbed dose rate data was collected using handheld radiation survey meters and remaining were measured using environmental Thermo Luminescent Dosimeters. The mean absorbed dose rate of the entire country including several mineralized regions, was found to be 96 ± 21 nGy/h. The median, Geometric Mean and Geometric Standard Deviation values of absorbed dose rate were 94, 94 and 1.2 nGy/h, respectively. Among the High Background Radiation Areas of the country, absorbed dose rate varied from 700 to 9562 nGy/h in Karunagappally area of Kollam district, Kerala. The absorbed dose rate in the present nationwide study is comparable with the global database.


Subject(s)
Radiation Monitoring , Soil Pollutants, Radioactive , Soil Pollutants, Radioactive/analysis , Soil , India , Radiation Dosimeters , Background Radiation , Radiation Dosage
4.
New Microbes New Infect ; 48: 101003, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35928517
5.
Ann Oncol ; 33(5): 500-510, 2022 05.
Article in English | MEDLINE | ID: mdl-35306155

ABSTRACT

BACKGROUND: Identification of residual disease in patients with localized non-small cell lung cancer (NSCLC) following treatment with curative intent holds promise to identify patients at risk of relapse. New methods can detect circulating tumour DNA (ctDNA) in plasma to fractional concentrations as low as a few parts per million, and clinical evidence is required to inform their use. PATIENTS AND METHODS: We analyzed 363 serial plasma samples from 88 patients with early-stage NSCLC (48.9%/28.4%/22.7% at stage I/II/III), predominantly adenocarcinomas (62.5%), treated with curative intent by surgery (n = 61), surgery and adjuvant chemotherapy/radiotherapy (n = 8), or chemoradiotherapy (n = 19). Tumour exome sequencing identified somatic mutations and plasma was analyzed using patient-specific RaDaR™ assays with up to 48 amplicons targeting tumour-specific variants unique to each patient. RESULTS: ctDNA was detected before treatment in 24%, 77% and 87% of patients with stage I, II and III disease, respectively, and in 26% of all longitudinal samples. The median tumour fraction detected was 0.042%, with 63% of samples <0.1% and 36% of samples <0.01%. ctDNA detection had clinical specificity >98.5% and preceded clinical detection of recurrence of the primary tumour by a median of 212.5 days. ctDNA was detected after treatment in 18/28 (64.3%) of patients who had clinical recurrence of their primary tumour. Detection within the landmark timepoint 2 weeks to 4 months after treatment end occurred in 17% of patients, and was associated with shorter recurrence-free survival [hazard ratio (HR): 14.8, P <0.00001] and overall survival (HR: 5.48, P <0.0003). ctDNA was detected 1-3 days after surgery in 25% of patients yet was not associated with disease recurrence. Detection before treatment was associated with shorter overall survival and recurrence-free survival (HR: 2.97 and 3.14, P values 0.01 and 0.003, respectively). CONCLUSIONS: ctDNA detection after initial treatment of patients with early-stage NSCLC using sensitive patient-specific assays has potential to identify patients who may benefit from further therapeutic intervention.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Circulating Tumor DNA , Lung Neoplasms , Small Cell Lung Carcinoma , Biomarkers, Tumor/genetics , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/therapy , Circulating Tumor DNA/genetics , Disease Progression , Humans , Lung Neoplasms/genetics , Lung Neoplasms/therapy , Neoplasm Recurrence, Local/pathology , Prospective Studies
6.
Phys Rev Lett ; 128(1): 011801, 2022 Jan 07.
Article in English | MEDLINE | ID: mdl-35061499

ABSTRACT

Dark matter with Planck-scale mass (≃10^{19} GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark matter was performed with a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate signals were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between 8.3×10^{6} and 1.2×10^{19} GeV/c^{2}, and ^{40}Ar-scattering cross sections between 1.0×10^{-23} and 2.4×10^{-18} cm^{2}. These results are interpreted as constraints on composite dark matter models with two different nucleon-to-nuclear cross section scalings.

8.
Eur Phys J C Part Fields ; 81(9): 823, 2021.
Article in English | MEDLINE | ID: mdl-34720726

ABSTRACT

The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. The largest background comes from 39 Ar beta decays and is suppressed using pulse-shape discrimination (PSD). We use two types of PSD estimator: the prompt-fraction, which considers the fraction of the scintillation signal in a narrow and a wide time window around the event peak, and the log-likelihood-ratio, which compares the observed photon arrival times to a signal and a background model. We furthermore use two algorithms to determine the number of photons detected at a given time: (1) simply dividing the charge of each PMT pulse by the mean single-photoelectron charge, and (2) a likelihood analysis that considers the probability to detect a certain number of photons at a given time, based on a model for the scintillation pulse shape and for afterpulsing in the light detectors. The prompt-fraction performs approximately as well as the log-likelihood-ratio PSD algorithm if the photon detection times are not biased by detector effects. We explain this result using a model for the information carried by scintillation photons as a function of the time when they are detected.

9.
Clin. transl. oncol. (Print) ; 23(11): 2206-2219, nov. 2021. ilus
Article in English | IBECS | ID: ibc-223417

ABSTRACT

Cancer genomics has evolved over the years from understanding the pathogenesis of cancer to screening the future possibilities of cancer occurrence. Understanding the genetic profile of tumors holds a prognostic as well as a predictive value in this era of therapeutic surveillance, molecular remission, and precision medicine. Identifying molecular markers in tumors is the current standard of approach, and requires an efficient combination of an accessible sample type and a profoundly sensitive technique. Liquid biopsy or cell-free DNA has evolved as a novel sample type with promising results in recent years. Although cell-free DNA has significant role in various cancer types, this review focuses on its application in Non-Hodgkin’s Lymphoma. Beginning with the current concept and clinical relevance of minimal residual disease in Non-Hodgkin’s lymphoma, we discuss the literature on circulating DNA and its evolving application in the realm of cutting-edge technology (AU)


Subject(s)
Humans , Biomarkers, Tumor/blood , Circulating Tumor DNA/blood , Lymphoma, Non-Hodgkin/genetics , High-Throughput Nucleotide Sequencing , Genotyping Techniques , Lymphoma, Non-Hodgkin/blood , Lymphoma, Non-Hodgkin/pathology , Liquid Biopsy , Mutation , Neoplasm, Residual/genetics , Polymerase Chain Reaction , Positron-Emission Tomography , Prognosis
10.
Malays Orthop J ; 15(2): 143-150, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34429835

ABSTRACT

INTRODUCTION: To evaluate the trends of C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR) in the first three weeks after uncomplicated total hip (THR) and total knee (TKR) arthroplasty/replacement in the Indian population and to compare it with available literature. MATERIALS AND METHODS: A total of 90 patients were enrolled for this prospective study, of which 30 were unilateral THR, 30 were unilateral TKR (U/L TKR) and 30 were simultaneous bilateral TKR (B/L TKR). Serum CRP and ESR were measured on the day before surgery and post-operatively on day 1st, 2nd, 3rd, 7th, 12th, and at the end of 3rd week. RESULTS: CRP showed a peak at day 2nd with normalisation to pre-operative value by the end of 3rd week. While ESR showed a peak on day 3rd and continued to remain elevated even at end of 3rd week post-operatively. Both mean CRP and ESR values were higher in THR patients followed by in B/L TKR and then in U/L TKR patients. CONCLUSION: CRP persists to be the best acute phase reactant in the early post-operative phase with a relatively typical pattern as compared to ESR. CRP values peak at post-operative day 2nd and then show a gradual decline. However, its normalisation to pre-operative baseline values may vary among different groups of population.

11.
J Synchrotron Radiat ; 28(Pt 4): 1193-1201, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34212884

ABSTRACT

A hard X-ray engineering applications beamline (BL-02) was commissioned recently and started operation in March 2019 at the Indian synchrotron source, Indus-2. This bending-magnet-based beamline is capable of operating in various beam modes, viz. white, pink and monochromatic beam. The beamline utilizes the X-ray diffraction technique in energy-dispersive and angle-dispersive modes to carry out experiments mainly focused on engineering problems, viz. stress measurement, texture measurement and determination of elastic constants in a variety of bulk as well as thin-film samples. An open-cradle six-circle diffractometer with ∼12 kg load capacity allows accommodation of a wide variety of engineering samples and qualifies the beamline as a unique facility at Indus-2. The high-resolution mode of this beamline is suitably designed so as to carry out line profile analysis for characterization of micro- and nano-structures. In the present article the beamline is described starting from the beamline design, layout, optics involved, various operational modes and experimental stations. Experiments executed to validate the beamline design parameters and to demonstrate the capabilities of the beamline are also described. The future facilities to be incorporated to enhance the capabilities of the beamline are also discussed.

12.
Clin Transl Oncol ; 23(11): 2206-2219, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33991328

ABSTRACT

Cancer genomics has evolved over the years from understanding the pathogenesis of cancer to screening the future possibilities of cancer occurrence. Understanding the genetic profile of tumors holds a prognostic as well as a predictive value in this era of therapeutic surveillance, molecular remission, and precision medicine. Identifying molecular markers in tumors is the current standard of approach, and requires an efficient combination of an accessible sample type and a profoundly sensitive technique. Liquid biopsy or cell-free DNA has evolved as a novel sample type with promising results in recent years. Although cell-free DNA has significant role in various cancer types, this review focuses on its application in Non-Hodgkin's Lymphoma. Beginning with the current concept and clinical relevance of minimal residual disease in Non-Hodgkin's lymphoma, we discuss the literature on circulating DNA and its evolving application in the realm of cutting-edge technology.


Subject(s)
Circulating Tumor DNA/blood , Lymphoma, Non-Hodgkin/genetics , Lymphoma, Non-Hodgkin/pathology , Biomarkers, Tumor/blood , Cell-Free Nucleic Acids/blood , Flow Cytometry , Genetic Markers , Genotyping Techniques , High-Throughput Nucleotide Sequencing , Humans , Liquid Biopsy , Lymphoma/blood , Lymphoma/genetics , Lymphoma, Non-Hodgkin/blood , Lymphoma, Non-Hodgkin/diagnostic imaging , Mutation , Neoplasm, Residual/blood , Neoplasm, Residual/genetics , Neoplasm, Residual/pathology , Polymerase Chain Reaction/methods , Positron-Emission Tomography , Precision Medicine , Prognosis , Transcriptome , Translocation, Genetic
13.
Article in English | WPRIM (Western Pacific) | ID: wpr-922748

ABSTRACT

@#Introduction: To evaluate the trends of C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR) in the first three weeks after uncomplicated total hip (THR) and total knee (TKR) arthroplasty/replacement in the Indian population and to compare it with available literature. Material and methods: A total of 90 patients were enrolled for this prospective study, of which 30 were unilateral THR, 30 were unilateral TKR (U/L TKR) and 30 were simultaneous bilateral TKR (B/L TKR). Serum CRP and ESR were measured on the day before surgery and postoperatively on day 1st, 2nd, 3rd, 7th, 12th, and at the end of 3rd week. Results: CRP showed a peak at day 2nd with normalisation to pre-operative value by the end of 3rd week. While ESR showed a peak on day 3rd and continued to remain elevated even at end of 3rd week post-operatively. Both mean CRP and ESR values were higher in THR patients followed by in B/L TKR and then in U/L TKR patients. Conclusion: CRP persists to be the best acute phase reactant in the early post-operative phase with a relatively typical pattern as compared to ESR. CRP values peak at postoperative day 2nd and then show a gradual decline. However, its normalisation to pre-operative baseline values may vary among different groups of population.

14.
Eur Psychiatry ; 63(1): e72, 2020 08 11.
Article in English | MEDLINE | ID: mdl-32778184

ABSTRACT

BACKGROUND: Abnormalities in the semantic and syntactic organization of speech have been reported in individuals at clinical high-risk (CHR) for psychosis. The current study seeks to examine whether such abnormalities are associated with changes in brain structure and functional connectivity in CHR individuals. METHODS: Automated natural language processing analysis was applied to speech samples obtained from 46 CHR and 22 healthy individuals. Brain structural and resting-state functional imaging data were also acquired from all participants. Sparse canonical correlation analysis (sCCA) was used to ascertain patterns of covariation between linguistic features, clinical symptoms, and measures of brain morphometry and functional connectivity related to the language network. RESULTS: In CHR individuals, we found a significant mode of covariation between linguistic and clinical features (r = 0.73; p = 0.003), with negative symptoms and bizarre thinking covarying mostly with measures of syntactic complexity. In the entire sample, separate sCCAs identified a single mode of covariation linking linguistic features with brain morphometry (r = 0.65; p = 0.05) and resting-state network connectivity (r = 0.63; p = 0.01). In both models, semantic and syntactic features covaried with brain structural and functional connectivity measures of the language network. However, the contribution of diagnosis to both models was negligible. CONCLUSIONS: Syntactic complexity appeared sensitive to prodromal symptoms in CHR individuals while the patterns of brain-language covariation seemed preserved. Further studies in larger samples are required to establish the reproducibility of these findings.


Subject(s)
Brain Mapping , Brain/physiopathology , Linguistics , Multimodal Imaging , Psychotic Disorders/physiopathology , Psychotic Disorders/psychology , Adult , Female , Humans , Male , Natural Language Processing , Prodromal Symptoms , Psychotic Disorders/diagnosis , Young Adult
15.
Indian J Ophthalmol ; 68(8): 1569-1572, 2020 08.
Article in English | MEDLINE | ID: mdl-32709778

ABSTRACT

Purpose: To evaluate the astigmatism correcting effect of penetrating arcuate keratotomy (AK) done during femtosecond laser-assisted cataract surgery (FLACS). Methods: In this nonrandomized prospective study, 80 eyes of 70 patients were studied. The study included patients who underwent combined FLACS and AK, with corneal astigmatism ranging from 0.4 to 1.5 diopters (D). Femtosecond laser-assisted penetrating arcuate keratotomies were created at 8 mm optical zone at 80% depth and were centered at the limbus. Keratometric astigmatism was measured prior to and 3 months post-surgery. Vector analysis was performed using Power vector analysis method. Results: The mean preoperative keratometric astigmatism without accounting for axis was 0.85 ± 0.27 D, which reduced significantly to 0.47 ± 0.27 D at 3-month follow-up. The mean astigmatism correction attained without accounting for axis was 0.38 ± 0.32 D. The vector corrected mean preoperative astigmatism was 0.85 ± 0.27 D which reduced significantly to 0.50 ± 0.31 D postoperatively (P < 0.001, 95% CI). Vector corrected mean astigmatism correction attained was 0.35 ± 0.38 D. There were no significant intraoperative or postoperative complications. Conclusion: Preexisting astigmatism can be tackled effectively with penetrating AK during FLACS although under correction is observed with present nomograms. Further refinements may achieve better correction.


Subject(s)
Astigmatism , Cataract , Astigmatism/surgery , Cataract/complications , Cataract/diagnosis , Cornea/surgery , Corneal Topography , Humans , Keratoplasty, Penetrating , Lasers , Prospective Studies , Refraction, Ocular , Retrospective Studies , Visual Acuity
16.
Acta Gastroenterol Belg ; 83(1): 87-89, 2020.
Article in English | MEDLINE | ID: mdl-32233278

ABSTRACT

Azathioprine and 6-mercaptopurine have been widely used for maintenance of remission in patients with inflammatory bowel disease. The use of thiopurines is associated with multiple adverse effects including dose dependent cytopenias or idiosyncratic reaction. We report about a case of azathioprine related pancreatitis associated with polyarthralgia and panniculitis. Pancreatitis, polyarthritis and panniculitis (PPP) syndrome is an uncommon phenomenon which may accompany a number of pancreatic diseases including acute or chronic pancreatitis or pancreatic malignancy. To the best of our knowledge, this is the first report of Azathioprine related PPP syndrome.


Subject(s)
Crohn Disease , Arthritis , Azathioprine , Humans , Immunosuppressive Agents , Mercaptopurine , Panniculitis
17.
Oper Dent ; 45(1): 1-9, 2020.
Article in English | MEDLINE | ID: mdl-31567053

ABSTRACT

OBJECTIVE: To manage three cases of mild to moderate fluorosis by resin infiltration technique and to quantify the tooth color changes by measuring CIE L*a*b* values of digital photographs and calculating ΔE00 based on the CIEDE2000 formula using Adobe Photoshop software. METHODS AND MATERIALS: Three cases of mild to moderate fluorosis were treated with a combination of bleaching and a resin infiltration technique. CIE L*a*b* values of 18 fluorosed spots were measured from digital photographs of these cases at four different stages-preoperative, postbleaching, postinfiltration and at 12-month follow-up-using Adobe Photoshop software, and ΔE00 was calculated based on the CIEDE2000 formula. The ΔE00 values of all 18 points obtained at different stages were submitted to statistical analysis (α=0.05). RESULTS: In all the cases reported, clinically as well as by the photographic color analysis, it was found that the technique masked the lesions, improving the patients' esthetics, which was maintained even at 12-month recall. Statistically significant difference in ΔE00 values was present between comparison of all stages (p<0.001) except between postinfiltration and the 12-month follow-up stage (p=0.642). CONCLUSION: A resin infiltration technique helped in the satisfactory management of white spot lesions of fluorosis, which were stable even at 12-month follow up. Quantitation of the changes was achieved using Adobe Photoshop software.


Subject(s)
Fluorosis, Dental , Color , Follow-Up Studies , Humans , Photography
18.
J Pediatric Infect Dis Soc ; 9(5): 587-595, 2020 Nov 10.
Article in English | MEDLINE | ID: mdl-31868913

ABSTRACT

BACKGROUND: Respiratory syncytial virus (RSV) is a major cause of hospitalizations in young children. We estimated the burden of community-onset RSV-associated hospitalizations among US children aged <2 years by extrapolating rates of RSV-confirmed hospitalizations in 4 surveillance states and using probabilistic multipliers to adjust for ascertainment biases. METHODS: From October 2014 through April 2015, clinician-ordered RSV tests identified laboratory-confirmed RSV hospitalizations among children aged <2 years at 4 influenza hospitalization surveillance network sites. Surveillance populations were used to estimate age-specific rates of RSV-associated hospitalization, after adjusting for detection probabilities. We extrapolated these rates using US census data. RESULTS: We identified 1554 RSV-associated hospitalizations in children aged <2 years. Of these, 27% were admitted to an intensive care unit, 6% needed mechanical ventilation, and 5 died. Most cases (1047/1554; 67%) had no underlying condition. Adjusted age-specific RSV hospitalization rates per 100 000 population were 1970 (95% confidence interval [CI],1787 to 2177), 897 (95% CI, 761 to 1073), 531 (95% CI, 459 to 624), and 358 (95% CI, 317 to 405) for ages 0-2, 3-5, 6-11, and 12-23 months, respectively. Extrapolating to the US population, an estimated 49 509-59 867 community-onset RSV-associated hospitalizations among children aged <2 years occurred during the 2014-2015 season. CONCLUSIONS: Our findings highlight the importance of RSV as a cause of hospitalization, especially among children aged <2 months. Our approach to estimating RSV-related hospitalizations could be used to provide a US baseline for assessing the impact of future interventions.


Subject(s)
Hospitalization/statistics & numerical data , Respiratory Syncytial Virus Infections/epidemiology , Age Factors , Community-Acquired Infections/epidemiology , Community-Acquired Infections/mortality , Female , Humans , Infant , Infant, Newborn , Influenza, Human/epidemiology , Intensive Care Units/statistics & numerical data , Male , Population Surveillance , Respiration, Artificial/statistics & numerical data , Respiratory Syncytial Virus Infections/mortality , Respiratory Syncytial Virus, Human , Risk Factors , United States/epidemiology
19.
Proc Biol Sci ; 286(1909): 20191491, 2019 08 28.
Article in English | MEDLINE | ID: mdl-31431166

ABSTRACT

Pyruvate : ferredoxin oxidoreductase (PFO) and iron only hydrogenase ([Fe]-HYD) are common enzymes among eukaryotic microbes that inhabit anaerobic niches. Their function is to maintain redox balance by donating electrons from food oxidation via ferredoxin (Fd) to protons, generating H2 as a waste product. Operating in series, they constitute a soluble electron transport chain of one-electron transfers between FeS clusters. They fulfil the same function-redox balance-served by two electron-transfers in the NADH- and O2-dependent respiratory chains of mitochondria. Although they possess O2-sensitive FeS clusters, PFO, Fd and [Fe]-HYD are also present among numerous algae that produce O2. The evolutionary persistence of these enzymes among eukaryotic aerobes is traditionally explained as adaptation to facultative anaerobic growth. Here, we show that algae express enzymes of anaerobic energy metabolism at ambient O2 levels (21% v/v), Chlamydomonas reinhardtii expresses them with diurnal regulation. High O2 environments arose on Earth only approximately 450 million years ago. Gene presence/absence and gene expression data indicate that during the transition to high O2 environments and terrestrialization, diverse algal lineages retained enzymes of Fd-dependent one-electron-based redox balance, while the land plant and land animal lineages underwent irreversible specialization to redox balance involving the O2-insensitive two-electron carrier NADH.


Subject(s)
Adaptation, Physiological/physiology , Chlamydomonas reinhardtii/physiology , Ferredoxins/metabolism , NAD/metabolism , Anaerobiosis , Animals , Electron Transport , Energy Metabolism , Hydrogenase , Iron-Sulfur Proteins , Oxygen/metabolism
20.
Oper Dent ; 44(3): 221-226, 2019.
Article in English | MEDLINE | ID: mdl-31046649

ABSTRACT

This article describes the clinical protocol of using potassium iodide (KI) to reverse staining caused by silver diamine fluoride (SDF). SDF contains silver, fluoride, and ammonia. It has been used to arrest dental caries mainly in pediatric applications. The major drawback of SDF application is the dark staining of both teeth and restorative materials. Hence, its use on adult dentition is limited. Improving the esthetic outcome by stain reduction would greatly enhance the opportunity for SDF's universal use. This case demonstrates how KI can effectively reverse the staining.


Subject(s)
Dental Caries , Potassium Iodide , Child , Fluorides, Topical , Humans , Quaternary Ammonium Compounds , Silver Compounds , Staining and Labeling
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