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The present work reports the rapid sweat detection inside a PPE kit using a flexible humidity sensor based on hydrothermally synthesized ZnO (zinc oxide) nanoflowers (ZNFs). Physical characterization of ZNFs was done using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), UV-visible, particle size analysis, Raman analysis, and X-ray photoelectron spectroscopy (XPS) analysis, and the hydrophilicity was investigated by using contact angle measurement. Fabrication of a flexible sensor was done by deposition on the paper substrate using the spin coating technique. It exhibited high sensitivity and low response and recovery times in the humidity range 10-95%RH. The sensor demonstrated the highest sensitivity of 296.70 nF/%RH within the humidity range 55-95%RH, and the rapid response and recovery times were also calculated and found as 5.10/1.70 s, respectively. The selectivity of the proposed sensor was also analyzed, and it is highly sensitive to humidity. The humidity sensing characteristics were theoretically witnessed in terms of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and electronic properties of sensing materials in ambient and humid conditions. These theoretical results are evidence of the interaction of ZnO with humidity. Overall, the present study provides a scope of architecture-enabled paper-based humidity sensors for the detection of sweat levels inside PPE kits for health workers.
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BACKGROUND: Healthcare providers (HPs) play a critical role in disseminating information about infant health and development. Two key developmental areas for infants are physical activity (PA) and communication. Few studies have examined HPs views of these topics. Thus, HPs may need support to promote these early development outcomes in infants. Thus, the study explored HPs' perceptions of infant PA and communication. METHODS: A total of 13 HPs with a wide variety of backgrounds were recruited. Zoom semi-structured interviews were based on the Health Belief Model. Deductive content analysis was utilized to analyze data. RESULTS: HPs knew little about PA guidelines. HPs were concerned about an infant's PA because of limited playtime and tummy time. Most HPs advised parents on PA and motor development milestones, with crawling, walking, and tummy time. HPs also wanted to learn about PA measurement tools. PA promotion was hindered by parents' busy schedules, lack of time, and language barriers. Most HPs advised parents on verbal and nonverbal communication. Many HPs were unfamiliar with communication assessment methods and wanted to learn more. CONCLUSIONS: HPs had limited knowledge about PA guidelines and communication measurement tools. Efforts are needed to identify easily accessible ways to educate HPs that could be disseminated to parents.
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Atitude do Pessoal de Saúde , Comunicação , Humanos , Lactente , Feminino , Masculino , Adulto , Exercício Físico/psicologia , Desenvolvimento Infantil/fisiologia , Pais/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/psicologia , Promoção da Saúde , Pesquisa QualitativaRESUMO
Preschool teachers are uniquely positioned to impact children's physical activity levels, yet the relationship between teachers' and children's physical activity levels has not been widely investigated. The purpose of this study was to explore preschool teachers' physical activity levels, practices, and perceptions and how this relates to children's physical activity at preschool centers. This convergent mixed methods study included eight teachers and 20 children from four preschool classrooms. Accelerometers were used to measure their physical activity. Pearson correlations were used to explore the relationship between teachers' and children's physical activity levels. Direct observation was used to contextualize children's physical activity while at preschool. Teachers completed a semi-structured interview to explore their physical activity perceptions and practices. On average, teachers and children were physically active for 50.2 ± 9.3% and 29.5 ± 7.0% of their time at preschool, respectively. A significant positive correlation (p = 0.02; r = 0.98) was found between teachers' and children's percent of time at preschool per day in moderate-to-vigorous physical activity. Children mostly engaged in low-intensity activities (stationary play; light walking) during free play both indoors and outdoors and were mostly sedentary during teacher-initiated group times. All teachers stated they had a positive influence on children's physical activity. Teachers commonly reported pain or health conditions as a barrier to their physical activity. There was a positive relationship between teachers' and children's physical activity. More research is needed to confirm this relationship and to explore the impacts of high amounts of occupational physical activity on teachers' health. Supplementary Information: The online version contains supplementary material available at 10.1007/s10643-023-01486-8.
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Diabetes is a major health challenge, and it is linked to a number of serious health issues, including cardiovascular disease (heart attack and stroke), diabetic nephropathy (kidney damage or failure), and birth defects. The detection of glucose has a direct and significant clinical importance in the management of diabetes. Herein, we demonstrate the application of in-situ synthesized Ti2C-TiO2 MXene nanocomposite for high throughput non-enzymatic electrochemical sensing of glucose. The nanocomposite was synthesized by controlled oxidation of Ti2C-MXene nanosheets using H2O2 at room temperature. The oxidation results in the opening up of Ti2C-MXene nanosheets and the formation of TiO2 nanocrystals on their surfaces as revealed in microscopic and spectroscopic analysis. Nanocomposite exhibited considerably high electrochemical response than parent Ti2C MXene, and hence utilized as a novel electrode material for enzyme-free sensitive and specific detection of glucose. Developed nanocomposite-based non-enzymatic glucose sensor (NEGS) displays a wide linearity range (0.1 µM-200 µM, R2 = 0.992), high sensitivity of 75.32 µA mM-1 cm-2, a low limit of detection (0.12 µM) and a rapid response time (~3s). NEGS has further shown a high level of repeatability and selectivity for glucose in serum spiked samples. The unveiled excellent sensing performance of NEGS is credited to synergistically improved electrochemical response of Ti2C MXene and TiO2 nanoparticles. All of these attributes highlight the potential of MXene nanocomposite as a next-generation NEGS for on the spot mass screening of diabetic patients.
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Diabetes Mellitus , Nanocompostos , Diabetes Mellitus/diagnóstico , Glucose/análise , Humanos , Peróxido de Hidrogênio/análise , Nanocompostos/química , Titânio/químicaRESUMO
The purpose of this research was to investigate the adsorption of arsenic (As) from aqueous solutions using MPAC-500 and MPAC-600 (magnetic-activated carbons synthesized from the peel of Pisum sativum (pea) pyrolyzed at 500 °C and 600 °C temperatures, respectively). The potential of both biosorbents for As adsorption was determined in batch and column mode. The characterization of both biosorbents was performed by energy dispersive spectroscopy, scanning electron microscope, pHZPC, particle size distribution, X-ray diffraction, zeta potential and Fourier-transform infrared spectroscopy. It was found that the efficiency of MPAC-600 was better than MPAC-500 for the adsorption of As(III) and As(V) ions. The adsorption capacities of MPAC-500 and MPAC-600 in removing As(III) were 0.7297 mg/g and 1.3335 mg/g, respectively, while the values of Qmax for As(V) on MPAC-500 and MPAC-600 were 0.4930 mg/g and 0.9451 mg/g, respectively. The Langmuir isotherm model was found to be the best fit for adsorption of As(III) by MPAC-500 and MPAC-600, as well as adsorption of As(V) by MPAC-500. The Freundlich isotherm model, on the other hand, was optimal for As(V) removal with MPAC-600. With R2 values close to unity, the pseudo-second-order kinetics were best fitted to the adsorption process of both As species. The Thomas model was used to estimate the breakthrough curves. The effects of coexisting oxyanions and regeneration studies were also carried out to examine the influence of oxyanions on As adsorption and reusability of biosorbents.
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Arsênio , Poluentes Químicos da Água , Adsorção , Arsênio/química , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Pisum sativum , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água , Poluentes Químicos da Água/químicaRESUMO
Accumulation of misfolded proteins in endoplasmic reticulum (ER) generates a stress condition in the cell. The cell combats ER stress by activating unfolded protein response (UPR) and ERAD (ER stress-associated degradation) pathway. Failure to restore favorable folding environment results in cell dysfunction and apoptosis. Various neurodegenerative disorders are characterized by the accumulation of misfolded protein, protein aggregates, and ER stress. GNE myopathy (GNEM) is a neuromuscular disorder pathologically characterized by rimmed vacuole formation due to the accumulation of protein aggregates. More than 200 mutations in key sialic acid biosynthetic enzyme UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) have been identified worldwide in the muscle biopsies of GNE myopathy patients. However, the cellular and molecular pathomechanism leading to the disease ar poorly understood. In the present study, the phenomenon of ER stress has been elucidated in GNE mutant cells overexpressing GNE mutations of Indian origin. The effect of GNE mutations on activation of UPR signaling via inositol-requiring transmembrane kinase/endoribonuclease 1 (IRE-1), protein kinase RNA-like endoplasmic reticulum kinase (PERK), and activating transcription factor-6 (ATF6) were deciphered to understand the effect of GNE mutations on these proteins. GRP78 was upregulated with increased X-box-binding protein-1 (XBP-1) splicing and CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) upregulation leading to increased apoptosis of GNE mutant cells. Insulin-like growth factor 1 (IGF-1) ligand rescued the cells from apoptotic phenotype by supporting cell survival mechanism. Our study indicates a balance of cell death and survival that decides cell fate and offers potential therapeutic targets to combat ER stress in diseases associated with dysfunctional UPR pathway.
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Estresse do Retículo Endoplasmático , Complexos Multienzimáticos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Doenças Neuromusculares/enzimologia , Resposta a Proteínas não Dobradas , Células HEK293 , Humanos , Complexos Multienzimáticos/genética , Ácido N-Acetilneuramínico/genética , Doenças Neuromusculares/genéticaRESUMO
BACKGROUND: Countries with the highest burden of maternal and newborn deaths and stillbirths often have little information on these deaths. Since over 81% of births worldwide now occur in facilities, using routine facility data could reduce this data gap. We assessed the availability, quality, and utility of routine labour and delivery ward register data in five hospitals in Bangladesh, Nepal, and Tanzania. This paper forms the baseline register assessment for the Every Newborn-Birth Indicators Research Tracking in Hospitals (EN-BIRTH) study. METHODS: We extracted 21 data elements from routine hospital labour ward registers, useful to calculate selected maternal and newborn health (MNH) indicators. The study sites were five public hospitals during a one-year period (2016-17). We measured 1) availability: completeness of data elements by register design, 2) data quality: implausibility, internal consistency, and heaping of birthweight and explored 3) utility by calculating selected MNH indicators using the available data. RESULTS: Data were extracted for 20,075 births. Register design was different between the five hospitals with 10-17 of the 21 selected MNH data elements available. More data were available for health outcomes than interventions. Nearly all available data elements were > 95% complete in four of the five hospitals and implausible values were rare. Data elements captured in specific columns were 85.2% highly complete compared to 25.0% captured in non-specific columns. Birthweight data were less complete for stillbirths than live births at two hospitals, and significant heaping was found in all sites, especially at 2500g and 3000g. All five hospitals recorded count data required to calculate impact indicators including; stillbirth rate, low birthweight rate, Caesarean section rate, and mortality rates. CONCLUSIONS: Data needed to calculate MNH indicators are mostly available and highly complete in EN-BIRTH study hospital routine labour ward registers in Bangladesh, Nepal and Tanzania. Register designs need to include interventions for coverage measurement. There is potential to improve data quality if Health Management Information Systems utilization with feedback loops can be strengthened. Routine health facility data could contribute to reduce the coverage and impact data gap around the time of birth.
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Confiabilidade dos Dados , Salas de Parto , Sistema de Registros/normas , Bangladesh , Feminino , Humanos , Recém-Nascido , Nepal , Gravidez , TanzâniaRESUMO
Regioselective ring nitration of N-alkyl anilines is reported using tert-butyl nitrite. The reactions proceed efficiently with a wide range of substrates providing synthetically useful N-nitroso N-alkyl nitroanilines in excellent yields which can be easily converted into N-alkyl phenylenediamines and N-alkyl nitroanilines using Zn-AcOH and HCl/MeOH, respectively.
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A mild and efficient method is demonstrated for the transamidation of secondary amides with various amines including primary, secondary, cyclic and acyclic amines in the presence of tert-butyl nitrite. The reaction proceeds through the N-nitrosamide intermediate and provides the transamidation products in good to excellent yields at room temperature. Moreover, the developed methodology does not require any catalyst or additives.
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Molybdenum disulfide (MoS2) quantum dots (QDs) are successfully synthesized by facile synthesis using ultrasonication assisted liquid exfoliation technique. The high and low boiling point solvents: N-methyl-pyrrolidone (NMP) and ethanol-water solution have been used for synthesis of MoS2 QDs. Similar size distribution of MoS2 QDs synthesized in two different solvents have been observed from the transmission electron microscopy and average size of these QDs are â¼5 nm. The film of MoS2 QDs is used to fabricate humidity sensor. The large edge to volume ratio and high surface active sites of QDs enhanced the water adsorption even at low humidity environment (<37% RH). The humidity sensing analysis shows that sensing film of MoS2 QDs synthesized in ethanol-water has an average sensitivity of 2.78 MΩ/%RH with fast response time (11 s), good repeatability and high stability. In view of these results, the work is highly applicable to fabricate high performance MoS2 QDs humidity sensor.
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Cyclin F protein, also known as FBXO1, is the largest among all cyclins and oscillates in the cell cycle like other cyclins. Apart from being a G2/M cyclin, cyclin F functions as the substrate-binding subunit of SCFcyclin F E3 ubiquitin ligase. In a gene expression analysis performed to identify novel gene modulations associated with cell cycle dysregulation during HIV-1 infection in CD4+ T cells, we observed down-regulation of the cyclin F gene (CCNF). Later, using gene overexpression and knockdown studies, we identified cyclin F as negatively influencing HIV-1 viral infectivity without any significant impact on virus production. Subsequently, we found that cyclin F negatively regulates the expression of viral protein Vif (viral infectivity factor) at the protein level. We also identified a novel host-pathogen interaction between cyclin F and Vif protein in T cells during HIV-1 infection. Mutational analysis of a cyclin F-specific amino acid motif in the C-terminal region of Vif indicated rescue of the protein from cyclin F-mediated down-regulation. Subsequently, we showed that Vif is a novel substrate of the SCFcyclin F E3 ligase, where cyclin F mediates the ubiquitination and proteasomal degradation of Vif through physical interaction. Finally, we showed that cyclin F augments APOBEC3G expression through degradation of Vif to regulate infectivity of progeny virions. Taken together, our results demonstrate that cyclin F is a novel F-box protein that functions as an intrinsic cellular regulator of HIV-1 Vif and has a negative regulatory effect on the maintenance of viral infectivity by restoring APOBEC3G expression.
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Ciclinas/fisiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Vírion/patogenicidade , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo , Desaminase APOBEC-3G/metabolismo , Linfócitos T CD4-Positivos , Células Cultivadas , Ciclinas/genética , Ciclinas/metabolismo , Proteínas F-Box , Perfilação da Expressão Gênica , Regulação Viral da Expressão Gênica , Humanos , Processamento de Proteína Pós-TraducionalRESUMO
A conversion of o-phenylenediamines into benzotriazoles was achieved at room temperature using tert-butyl nitrite. The optimized conditions are also well suited for the transformation of sulfonyl and acyl hydrazines into corresponding azides. This protocol does not require any catalyst or acidic medium. The desired products were obtained in excellent yields in a short span of time.
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HIV-1 efficiently hijacks host cellular machinery and exploits a plethora of host-viral interactions for its successful survival. Identifying host factors that affect susceptibility or resistance to HIV-1 may offer a promising therapeutic strategy against HIV-1. Previously, we have reported that heat shock proteins, HSP40 and HSP70 reciprocally regulate HIV-1 gene-expression and replication. In the present study, we have identified HSP70 binding protein 1 (HspBP1) as a host-intrinsic inhibitor of HIV-1. HspBP1 level was found to be significantly down modulated during HIV-1 infection and virus production inversely co-related with HspBP1 expression. Our results further demonstrate that HspBP1 inhibits HIV-1 long terminal repeat (LTR) promoter activity. Gel shift and chromatin immunoprecipitation assays revealed that HspBP1 was recruited on HIV-1 LTR at NF-κB enhancer region (κB sites). The binding of HspBP1 to κB sites obliterates the binding of NF-κB hetero-dimer (p50/p65) to the same region, leading to repression in NF-κB mediated activation of LTR-driven gene-expression. HspBP1 also plays an inhibitory role in the reactivation of latently infected cells, corroborating its repressive effect on NF-κB pathway. Thus, our results clearly show that HspBP1 acts as an endogenous negative regulator of HIV-1 gene-expression and replication by suppressing NF-κB-mediated activation of viral transcription.
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Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Infecções por HIV/genética , HIV-1/genética , NF-kappa B/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Regulação Viral da Expressão Gênica , Infecções por HIV/virologia , Repetição Terminal Longa de HIV/genética , HIV-1/patogenicidade , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Interações Hospedeiro-Parasita/genética , Humanos , Células Jurkat , Ligação Proteica , Ativação Transcricional/genética , Replicação Viral/genéticaRESUMO
The copper meditated N-methylation of sulfoximines using methylboronic acid is reported. The reactions provide excellent yields in a short span of time under mild conditions. The optimized conditions were also found to be suitable for the N-alkylation of sulfoximine with different alkylboronic acids. In addition, N-methylation and cyclopropylation of the bioactive l-methionine sulfoximine derivative was demonstrated under standard reaction conditions.
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BACKGROUND & OBJECTIVES: Rheumatic fever (RF) and rheumatic heart disease (RHD) are the autoimmune sequelae caused by Group A Streptococcus. RHD still remains a major concern in the developing countries due to its poor diagnosis, lack of vaccines and social awareness among population. This study was aimed to identify the plausible early- and late-stage disease markers associated with RF/RHD. METHODS: A total of 84 patients with confirmed pharyngitis (n=18), RF (n=23) and RHD (n=43) were included in the comparative analysis of different factors involved in host-pathogen interaction during RF/RHD pathogenesis. RESULTS: This study revealed high titre of serum antistreptolysin O (ASO) antibody in pharyngitis compared to RF and RHD patients, whereas procollagen type 1 C-peptide (PICP) level was elevated in RHD which showed an inverse correlation with serum ASO titre. The significant elevation of serum anti-peptide associated with RF (PARF) antibody in RF patients was correlated as a probable stage-specific determinant. In addition, pro-inflammatory cytokine profile revealed high levels of interleukin-12 (IL-12)/IL-23p40, IL-17A in RF, whereas IL-6 concentration was higher in RHD compared to healthy controls. INTERPRETATION & CONCLUSIONS: The overall assessment of the factors/ disease markers involved in host-pathogen interaction in RF/RHD may be suggestive of plausible disease marker in different groups of patients. Further studies with larger sample need to be done to better understand RF/RHD pathogenesis.
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Biomarcadores/sangue , Faringite/sangue , Febre Reumática/sangue , Cardiopatia Reumática/sangue , Adolescente , Adulto , Idoso , Anticorpos/sangue , Antiestreptolisina/sangue , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Interações Hospedeiro-Patógeno/genética , Humanos , Índia , Masculino , Lectina de Ligação a Manose/sangue , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Faringite/genética , Faringite/microbiologia , Faringite/patologia , Pró-Colágeno/sangue , Febre Reumática/genética , Febre Reumática/microbiologia , Febre Reumática/patologia , Cardiopatia Reumática/genética , Cardiopatia Reumática/microbiologia , Cardiopatia Reumática/patologia , Streptococcus pyogenes/patogenicidadeRESUMO
Microbial degradation is a useful tool to prevent chemical pollution in soil. In the present study, in-situ bioremediation of polyaromatic hydrocarbons (PAHs) by microbial consortium consisting of Serratia marcescens L-11, Streptomyces rochei PAH-13 and Phanerochaete chrysosporium VV-18 has been reported. In preliminary studies, the consortium degraded nearly 60-70% of PAHs in broth within 7 days under controlled conditions. The same consortium was evaluated for its competence under natural conditions by amending the soil with ammonium sulphate, paddy straw and compost. Highest microbial activity in terms of dehydrogenase, FDA hydrolase and aryl esterase was recorded on the 5(th) day. The degradation rate of PAHs significantly increased up to 56-98% within 7 days under in-situ however almost complete dissipation (83.50-100%) was observed on the 30(th) day. Among all the co-substrates evaluated, faster degradation of PAHs was observed in compost amended soil wherein fluorene, anthracene, phenanthrene and pyrene degraded with half-life of 1.71, 4.70, 2.04 and 6.14 days respectively. Different degradation products formed were also identified by GC-MS. Besides traces of parent PAHs eleven non-polar and five polar products were identified by direct and silylation reaction respectively. Various products formed indicated that consortium was capable to degrade PAHs by oxidation to mineralization.
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Biodegradação Ambiental , Hidrocarbonetos Aromáticos/metabolismo , Consórcios Microbianos , Compostos Policíclicos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solo/química , Meia-Vida , Hidrocarbonetos Aromáticos/química , Phanerochaete/metabolismo , Compostos Policíclicos/química , Poluentes do Solo/análise , Poluentes do Solo/química , Streptomyces/metabolismoRESUMO
Polyaromatic hydrocarbons (PAHs) utilizing bacteria were isolated from soils of seven sites of Mathura refinery, India. Twenty-six bacterial strains with different morphotypes were isolated. These strains were acclimatized to utilize a mixture of four polycyclic aromatic hydrocarbons, i.e., anthracene, fluorene, phenanthrene, and pyrene, each at 50 mg/L concentration as sole carbon source. Out of total isolates, 15 potent isolates were subjected to 16S rDNA sequencing and identified as a member of diverse genera, i.e., Bacillus, Acinetobacter, Stenotrophomonas, Alcaligenes, Lysinibacillus, Brevibacterium, Serratia, and Streptomyces. Consortium of four promising isolates (Acinetobacter, Brevibacterium, Serratia, and Streptomyces) were also investigated for bioremediation of PAH mixture. This consortium was proved to be efficient PAH degrader resulting in 40-70 % degradation of PAH within 7 days. Results of this study indicated that these genera may play an active role in bioremediation of PAHs.
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Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bacillus/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Monitoramento Ambiental , Indústrias Extrativas e de Processamento , Fluorenos , Índia , Poluição por Petróleo , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos , Solo/química , Poluentes do Solo/análiseRESUMO
Antibodies to high-frequency antigens are rarely implicated in cases of hemolytic disease of the fetus and newborn (HDFN), yet they pose a challenge to both clinical staff and transfusion medicine, especially with the identification of the implicating antibody and the arrangement of compatible blood for intrauterine transfusion. Here we report one such interesting case of HDFN caused by an alloantibody to a high-frequency antigen belonging to the Rhesus (Rh) blood group system. The patient presented at the 19th week with Rh-isoimmunized pregnancy. She received six intrauterine transfusions (IUTs) at different intervals during the antenatal period. Arranging the blood of this rare blood group required great efforts from hospital administration, clinicians, and social workers. At 31 weeks, the fetus developed a non-reassuring non-stress test (NST). Hence, the baby was delivered by cesarean section. The baby fared well in the neonatal period. With great efforts and support from social health workers, the Japanese Red Cross society, the administration, and non-government organizations, the impossible became possible.
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BACKGROUND: Essential to a patient-centered approach to imaging individuals with chest pain is knowledge of differences in radiation effective dose across imaging modalities. Body mass index (BMI) is an important and underappreciated predictor of effective dose. This study evaluated the impact of BMI on estimated radiation exposure across imaging modalities. METHODS AND RESULTS: This was a retrospective analysis of patients with concern for cardiac ischemia undergoing positron emission tomography (PET)/computed tomography (CT), cadmium zinc telluride single-photon emission CT (SPECT) myocardial perfusion imaging, or coronary CT angiography (CCTA) using state-of-the-art imaging modalities and optimal radiation-sparing protocols. Radiation exposure was calculated across BMI categories based on established cardiac imaging-specific conversion factors. Among 9046 patients (mean±SD age, 64.3±13.1 years; 55% men; mean±SD BMI, 30.6±6.9 kg/m2), 4787 were imaged with PET/CT, 3092 were imaged with SPECT/CT, and 1167 were imaged with CCTA. Median (interquartile range) radiation effective doses were 4.4 (3.9-4.9) mSv for PET/CT, 4.9 (4.0-6.3) mSv for SPECT/CT, and 6.9 (4.0-11.2) mSv for CCTA. Patients at a BMI <20 kg/m2 had similar radiation effective dose with all 3 imaging modalities, whereas those with BMI ≥20 kg/m2 had the lowest effective dose with PET/CT. Radiation effective dose and variability increased dramatically with CCTA as BMI increased, and was 10 times higher in patients with BMI >45 kg/m2 compared with <20 kg/m2 (median, 26.9 versus 2.6 mSv). After multivariable adjustment, PET/CT offered the lowest effective dose, followed by SPECT/CT, and then CCTA (P<0.001). CONCLUSIONS: Although median radiation exposure is modest across state-of-the-art PET/CT, SPECT/CT, and CCTA systems using optimal radiation-sparing protocols, there are significant variations across modalities based on BMI. These data are important for making patient-centered decisions for ischemic testing.