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1.
Transfus Apher Sci ; 63(1): 103862, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38135545

RESUMO

BACKGROUND AND OBJECTIVES: ABO-incompatible transplantations allow patients to receive timely transplants. Isoagglutinin titration to ascertain levels of incompatible antibodies in the recipient is important in determining patient selection and transplant survivability. To find out the prevalent trends in India, the largest, first of its kind survey was carried out among the transplant centers regarding their practices in isoagglutinin titration. METHODS: The survey was drafted by a working group of Transfusion and Transplant Immunology specialists from six different centers. Data was obtained via the use of an online questionnaire. RESULTS: Results were categorized into four categories, Hospital information, Titration methodology, Role of transfusion specialists and cut-off titers. Most centers had a well-established solid-organ transplant program with considerable number of ABO-incompatible transplantations. Most centers performed isoagglutinin titration in Transfusion Medicine department. Column Agglutination Technique (CAT) was the most common method, using EDTA blood samples and freshly-prepared in-house pooled cells. Most centers had a turn-around time of less than 12 h. While the policy for ascertaining baseline and threshold titers is well-defined in ABO-incompatible renal transplants, variations from center to center still exist for ABO-incompatible liver transplants. Most centers required a Transfusion Medicine consultation for the patients before such transplants. CONCLUSION: With increasing ABO-incompatible kidney and liver transplants across the country, the role of Transfusion medicine specialists has become vital in pre-conditioning regimes enabling the viability and success of such transplants. This was a unique survey that provided a snapshot of current trends and practices of isoagglutinin titration for ABO-incompatible transplants in India.


Assuntos
Transplante de Rim , Transplante de Fígado , Transplante de Órgãos , Humanos , Incompatibilidade de Grupos Sanguíneos , Transplante de Rim/métodos , Rim , Sistema ABO de Grupos Sanguíneos
2.
Transfus Med ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890119

RESUMO

INTRODUCTION: Anti-D detection and titration plays a major role in RhD negative antenatal cases both, for monitoring maternal as well as fetal status as well as initiation of early therapeutic interventions, such as intra-uterine transfusions (IUT) to improve maternal as well as fetal morbidity and mortality and reduce the adverse effects of haemolytic disease of fetus and newborn (HDFN). We conducted a survey focusing on the policies and procedures of anti-D detection and titration among major tertiary care centres across India. METHODOLOGY: The survey was drafted by a working group of transfusion medicine and immunohematology specialists from six different centres in India. Data were obtained via the use of an online questionnaire. RESULTS: Results were categorised into four categories, Hospital information, immuno-haematological testing methodology, clinical significance of anti-D testing and the role of transfusion medicine specialists. The survey highlighted the modalities as well as the methodologies of anti-D detection and titration in antenatal women across different major tertiary care centres in India. CONCLUSION: This survey provided a unique snapshot of the prevalent methodologies being employed by major tertiary care centres across the country for detection and titration of anti-D levels as well as the important role it plays in the therapy of affected antenatal women to minimise adverse effects on the fetus.

3.
Immunohematology ; 40(2): 65-72, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38910441

RESUMO

Autoimmune hemolytic anemia (AIHA) is a common term for several disorders that differ from one another in terms of etiology, pathogenesis, clinical features, and treatment. Management of patients with AIHA has become increasingly evidence-based in recent years. While this development has resulted in therapeutic improvements, it also carries increased requirements for optimal diagnosis using more advanced laboratory tests. Unfortunately, limited data are available from developing countries regarding the testing and transfusion management of patients with AIHA. The main objective of this survey was to explore the current immunohematologic testing practices for the diagnosis of AIHA in India. This online survey consisted of 30 questions, covering the place of work, the number of AIHA cases encountered in the 3 preceding years, testing method(s), transfusion management, and so forth. Individuals representing 89 laboratories completed the survey; only 78 of which responded that AIHA testing was performed in their facility's laboratory. The majority of respondents agreed that the most commonly affected age-group comprised individuals of older than 20 years, with a female preponderance. Regarding transfusion management, respondents indicated that transfusion with "best-match" red blood cell units remains the most common practice. Column-agglutination technology is used by 92 percent of respondents as the primary testing method. Although a monospecific direct antiglobulin test is available at 73 percent of the sites, most of them have limited access to other resources that could diagnose cold or mixed AIHA. Merely 49 percent of responding laboratories have the resources to perform adsorption studies for the detection of alloantibodies. Furthermore, three-cell antibody screening reagents are unavailable at 32 percent of laboratories. In 72 percent of centers, clinical hematologists would prefer to consult a transfusion medicine specialist before administering treatment to AIHA patients. There is unanimous agreement regarding the need for a national registry. The survey data indicate wide variability in testing practices for patients with AIHA in India. Future studies are needed to focus on the feasibility and cost-effectiveness of different testing strategies for developing countries.


Assuntos
Anemia Hemolítica Autoimune , Humanos , Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/sangue , Anemia Hemolítica Autoimune/imunologia , Índia , Inquéritos e Questionários , Feminino , Masculino , Adulto , Transfusão de Sangue , Teste de Coombs/métodos , Adulto Jovem
4.
Transfus Apher Sci ; 62(3): 103703, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36934038

RESUMO

Autoimmune Hemolytic Anemia (AIHA) in childhood is uncommon and estimated to be three per million annually under 18 years of age. Detailed immunohematological and clinical characterizations are essential for correct diagnosis of the disease and its management. In this study we described AIHA in children with regards to patient demography, underlying etiology, disease classification, antibody characterization, clinical features, degree of in vivo hemolysis and transfusion management. The prospective observational study was conducted over a period of 6 years and included 29 children with newly diagnosed AIHA. Patient details were obtained from the hospital information system and patient treatment file. The median age of the children was 12 years with a female preponderance. Secondary AIHA was observed in 62.1% patients. The mean hemoglobin and reticulocyte were 7.1 gm/dL and 8.8 percentages respectively. The median polyspecific direct antiglobulin test (DAT) grading was 3+. Red cell bound multiple autoantibodies were found in 27.6% children. Free serum autoantibodies were present in 62.1% patients. Twenty six of the 42 units transfused were "best match" or "least incompatible". Follow-up of 21 children showed clinical and laboratory improvement with DAT still positive at the end of 9 months. AIHA in childhood requires advanced and efficient clinical, immunohematological and transfusion support. Detailed characterization of AIHA is important, as they determine degree of in vivo hemolysis, disease severity, serological incompatibility and necessity of blood transfusion. Although blood transfusion in AIHA is a challenge but it should not be withheld in critically ill patients.


Assuntos
Anemia Hemolítica Autoimune , Humanos , Criança , Feminino , Adolescente , Anemia Hemolítica Autoimune/diagnóstico , Hemólise , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Autoanticorpos , Teste de Coombs
5.
Transfus Apher Sci ; 62(5): 103769, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37507272

RESUMO

Adsorption techniques are widely applied to detect underlying masked alloantibodies in warm autoimmune hemolytic anemia (WAIHA). We established various adsorption techniques with an aim to detect alloimmunization in WAIHA This study conducted over a period of nine years included 298 patients of WAIHA. Complete immunohematological evaluation was performed on these 298 samples following departmental protocols. Clinical and laboratory details of patients were obtained from patient files. Various adsorption methods were performed and statistically evaluated in the study. Out of 479 cases of autoimmune hemolytic anemia, WAIHA comprised of 62.2 % (N = 298). A total of 139 (46.6 %) serum samples revealed autoantibodies. Adsorption study was performed in 101 (72.7 %) indicated samples and 24 (23.8 %) of these showed 26 alloantibodies. Among the patients subjected to adsorption study hemolytic marker were significantly deranged in the alloimmunization group (p < 0.01). Polyethylene glycol (PEG) adsorption was the quickest (52.2-54.6 min) of all adsorption techniques with minimum (1.3-1.5) numbers of adsorptions needing for complete removal of serum antibodies. The LISS-papain (LP) technique was found to be more sensitive and specific compared to the other two techniques. The agreement between PEG adsorption and LP adsorption was found to be 'perfect' (96.4 %) with a Cohen's kappa (k) value of 0.9. We conclude that identification of alloantibody specificities underlying a warm autoantibody is critical for a safe and effective transfusion. All WAIHA patients with history of blood transfusion, pregnancy or both should be subjected to adsorption study. Selection of a suitable adsorption technique depends on multiple important factors.


Assuntos
Anemia Hemolítica Autoimune , Feminino , Gravidez , Humanos , Adsorção , Isoanticorpos , Eritrócitos , Autoanticorpos , Polietilenoglicóis
6.
Sensors (Basel) ; 23(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904721

RESUMO

Wearable devices with 5G technology are currently more ingrained in our daily lives, and they will now be a part of our bodies too. The requirement for personal health monitoring and preventive disease is increasing due to the predictable dramatic increase in the number of aging people. Technologies with 5G in wearables and healthcare can intensely reduce the cost of diagnosing and preventing diseases and saving patient lives. This paper reviewed the benefits of 5G technologies, which are implemented in healthcare and wearable devices such as patient health monitoring using 5G, continuous monitoring of chronic diseases using 5G, management of preventing infectious diseases using 5G, robotic surgery using 5G, and 5G with future of wearables. It has the potential to have a direct effect on clinical decision making. This technology could improve patient rehabilitation outside of hospitals and monitor human physical activity continuously. This paper draws the conclusion that the widespread adoption of 5G technology by healthcare systems enables sick people to access specialists who would be unavailable and receive correct care more conveniently.


Assuntos
Atenção à Saúde , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica , Hospitais , Tecnologia
7.
J Allergy Clin Immunol ; 149(1): 113-124.e7, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34146578

RESUMO

BACKGROUND: Many patients with severe asthma (SA) fail to respond to type 2 inflammation-targeted therapies. We previously identified a cohort of subjects with SA expressing type 1 inflammation manifesting with IFN-γ expression and variable type 2 responses. OBJECTIVE: We investigated the role of the chemotactic receptors C-X-C chemokine receptor 3 (CXCR3) and C-C chemokine receptor 5 (CCR5) in establishing type 1 inflammation in SA. METHODS: Bronchoalveolar lavage microarray data from the Severe Asthma Research Program I/II were analyzed for pathway expression and paired with clinical parameters. Wild-type, Cxcr3-/-, and Ccr5-/- mice were exposed to a type 1-high SA model with analysis of whole lung gene expression and histology. Wild-type and Cxcr3-/- mice were treated with a US Food and Drug Administration-approved CCR5 inhibitor (maraviroc) with assessment of airway resistance, inflammatory cell recruitment by flow cytometry, whole lung gene expression, and histology. RESULTS: A cohort of subjects with increased IFN-γ expression showed higher asthma severity. IFN-γ expression was correlated with CXCR3 and CCR5 expression, but in Cxcr3-/- and Ccr5-/- mice type 1 inflammation was preserved in a murine SA model, most likely owing to compensation by the other pathway. Incorporation of maraviroc into the experimental model blunted airway hyperreactivity despite only mild effects on lung inflammation. CONCLUSIONS: IFNG expression in asthmatic airways was strongly correlated with expression of both the chemokine receptors CXCR3 and CCR5. Although these pathways provide redundancy for establishing type 1 lung inflammation, inhibition of the CCL5/CCR5 pathway with maraviroc provided unique benefits in reducing airway hyperreactivity. Targeting this pathway may be a novel approach for improving lung function in individuals with type 1-high asthma.


Assuntos
Asma/imunologia , Receptores CCR5/imunologia , Receptores CXCR3/imunologia , Adulto , Resistência das Vias Respiratórias , Animais , Asma/tratamento farmacológico , Asma/fisiopatologia , Brônquios/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Antagonistas dos Receptores CCR5/uso terapêutico , Feminino , Humanos , Inflamação/imunologia , Inflamação/fisiopatologia , Interferon gama/imunologia , Masculino , Maraviroc/uso terapêutico , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptores CCR5/genética , Receptores CXCR3/genética , Mucosa Respiratória/imunologia , Índice de Gravidade de Doença , Adulto Jovem
8.
Transfus Apher Sci ; 61(6): 103492, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35773127

RESUMO

Autoantibody production in autoimmune haemolytic anemia (AIHA) is the result of the loss of self-immunological tolerance of the host. Here we investigated the various immunohematological markers that may influence the severity of in vivo hemolysis in warm AIHA (WAIHA). Complete direct antiglobulin test (DAT) evaluation and immunohematological characterization were performed in 247 patients of WAIHA following departmental protocols. Clinical and laboratory details of patients were obtained from patient file. The median age of WAIHA patients was 47 years with a female preponderance. Lymphoproliferative diseases were the major underlying causes of secondary WAIHA. The mean haemoglobin (Hb) and reticulocyte count (Retic) were 6.43 gm/dL and 7.58% respectively. Single autoantibody bound to red cells was investigated in 151 patients. The main IgG subclass was IgG1. Multiple autoantibodies like IgG+ C, IgG+IgA and IgG+IgA+C were found in 87 (35.2%) patients. Free autoantibodies were observed in 112 patients with a median indirect antiglobulin test (IAT) reactivity of 2+. Derangement of haematological and biochemical values was statistically significant with increase in DAT reactivity, presence of multiple autoantibodies on red cells, coating of red cells by IgG3 or multiple IgG subclass, higher DAT dilution and increasing IAT reactivity. We conclude that several important but simple immunohematological parameters may influence the degree of in vivo hemolysis in WAIHA. Since a set of common haematological and biochemical test determines the severity of in vivo hemolysis therefore a comprehensive clinical and immunohematological evaluation is advisable for a correct diagnostic and therapeutic workup of WAIHA.


Assuntos
Anemia Hemolítica Autoimune , Hemólise , Humanos , Feminino , Pessoa de Meia-Idade , Anemia Hemolítica Autoimune/diagnóstico , Imunoglobulina G , Autoanticorpos , Imunoglobulina A
9.
Curr Microbiol ; 79(12): 379, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329226

RESUMO

Streptomyces is genetically and functionally diverse genus known to produce a wide array of phenolics and flavonoids with significant biotechnological applications. 52 isolates belonging to 26 species of Streptomyces collected from Meghalaya, India were analyzed for their genetic diversity using BOX-PCR. Significant inter- and intra- generic diversity was observed among the Streptomyces isolates especially those belonging to S. cacaoi, S. lavendulae, S. olivochromogenes, S. aureus, S. flavovirens. During bioactivity screening of the isolates, S. rectiviolaceus MJM72 recorded the highest DPPH activity (77.13 ± 0.91%) whereas S. antimycoticus MSCA162 showed excellent ABTS radical scavenging activity (99.65 ± 0.41%). On the other hand, S. novaecaesareae MJM58 had the highest (756.4 ± 7.38 µg GAE g-1 fresh weight) phenolic content while S. rectiviolaceus MJM72 was recorded with the highest flavonoid content (69.3 ± 0.12 µg QE g-1 fresh weight). As compared to total flavonoid content, total phenolic content had a stronger correlation with antioxidant activities. HPLC analysis of five selected isolates showed presence of gallic acid and pyrocatechol as predominant phenolics. In case of flavonoids, three isolates showed presence of rutin with S. rochei MSCA130 having the highest rutin content (0.95 µg g-1 fresh weight). The results of this study showed high genetic diversity and antioxidant potential among the Streptomyces isolates.


Assuntos
Antioxidantes , Streptomyces , Extratos Vegetais , Streptomyces/genética , Staphylococcus aureus , Flavonoides , Fenóis , Rutina , Variação Genética
10.
Chem Biodivers ; 19(3): e202100857, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35103383

RESUMO

Bhitarkanika National Park is the second largest contiguous mangrove forest of India. Approximately 0.15 million mangrove depending population are found residing in and around 307 villages within the National Park. Despite being one of the most diverse mangrove habitations of India, the ethnopharmacological practices are meager in comparison to the other mangrove regions of India and Southeast Asia. The present review is aimed to congregate information on the therapeutic potential and ethnopharmacology of nine dominant mangrove species of the National Park, such as Aegiceras corniculatum, Avicenia marina, Avicenia officinalis, Ceriops decandra, Excoecaria agallocha, Heritiera fomes, Lumnitzera racemosa, Rhizophora mucronata, and Sonneratia apetala. Our aim is to generate social awareness among the mangrove dwellers to promote uses of folklore medicine using these tremendously potential mangrove plants, as a complementary step to strengthen community health. Further, we also want to grab the attention of researchers working in related disciplines, for their holistic and extensive studies towards bio-prospectation of the dominant mangrove plants of Bhitarkanika National Park.


Assuntos
Euphorbiaceae , Fitoterapia , Rhizophoraceae , Áreas Alagadas , Etnofarmacologia , Índia , Parques Recreativos
11.
Chem Biodivers ; 19(11): e202200266, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36151910

RESUMO

The unprecedented global pandemic of COVID-19 has created a daunting scenario urging an immediate generation of therapeutic strategy. Interventions to curb the spread of viral infection primarily include setting targets against the virus. Here in this study we target S protein to obstruct the viral attachment and entry and also the M pro to prevent the viral replication. For this purpose, the interaction of S protein and M pro with phytocompounds, sanguinarine and eugenol, and their derivatives were studied using computational tools. Docking studies gave evidence that 8-hydroxydihydrosanguinarine (8-HDS), a derivative of sanguinarine, showed maximum binding affinity with both the targets. The binding energies of the ligand with S protein and M pro scored to be ΔGb -9.4 Kcal/mol and ΔGb -10.3 Kcal/mol, respectively. MD simulation studies depict that the phytocompound could effectively cause structural perturbations in the targets which would affect their functions. 8-Hydroxydihydrosanguinarine distorts the α-helix in the secondary structure of M pro and RBD site of S protein. Protein-protein interaction study in presence of 8-hydroxydihydrosanguinarine also corroborate the above findings which indicate that this polyphenol interferes in the coupling of S protein and ACE2. The alterations in protonation of M pro suggest that the protein structure undergoes significant structural changes at neutral pH. ADME property of 8-hydroxydihydrosanguinarine indicates this could be a potential drug. This makes the phyto-alkaloid a possible therapeutic molecule for anti COVID-19 drug design.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Humanos , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Antivirais/farmacologia , Antivirais/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Piridonas
12.
Natl Med J India ; 35(4): 201-205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36715043

RESUMO

Background Most individuals with Covid-19 infection develop antibodies specific to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the dynamics of these antibodies is variable and not well-studied. We aimed to determine the titres of naturally acquired antibodies over a 12-week follow-up. Methods We recruited healthcare workers who had tested positive on a specific quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for SARS-CoV-2, and then tested for the presence of immunoglobulin G (IgG) antibody against the same virus at baseline and again at 6 and 12 weeks. The antibody titre was determined by a semi-quantitative assay based on signal/cut-off ratio. Healthcare workers with antibody positivity were divided into those with high titre (ratio ≥12) and low titre (<12). Their demographic details and risk factors were surveyed through a Google form and analysed in relation to the antibody titres at three time-points. Results Of the 286 healthcare workers, 10.48% had high antibody titres. Healthcare workers who had tested positive by qRT-PCR and those who had received the Bacille Calmette-Guérin (BCG) vaccination or other immune-boosters had a higher frequency of high antibody titres. While there was a significant decline in antibody titres at 6 and 12 weeks, 87.46% of individuals positive for IgG antibody persisted to have the antibody even at 12 weeks. Conclusion Healthcare workers who tested positive for SARS-CoV-2 on qRT-PCR had a high positivity for the specific antibody, which continued to express in them even at 12 weeks. Further follow-up is likely to enhance our understanding of antibody kinetics following SARS-CoV-2 infection.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , Estudos Longitudinais , SARS-CoV-2 , Pessoal de Saúde , Fatores de Risco , Anticorpos Antivirais
13.
Sensors (Basel) ; 22(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36365911

RESUMO

A compact and triple-band polarization converting reflective type metasurface (PCRM) with a high polarization conversion ratio (PCR) is proposed for strategic wireless antenna-integrated applications. The unit cell of the metasurface is composed of S- and G-shaped patches separated with a parasitic gap and the grounded via is connected to the full ground plane. The unit cell is etched on an FR4 substrate (dielectric constant, εr = 4.4, loss tangent, tan δ = 0.02), with compact dimensions of 10 mm3 × 10 mm3 × 1.6 mm3. This structure provides a resonance at 5.2 (ISM), 6.9, and 8.05 GHz (X-band) frequencies. The designed unit cell structure is studied for Transverse Electric (TE)/Transverse Magnetic (TM) incident waves and their responses to the various incident angles. The corresponding PCR is calculated, which shows 92% in the lower frequency band (5.2 GHz), 93% in the second frequency band (6.9 GHz), and 94% in the high-frequency band (8.05 GHz). The total efficiency of the structure shows 83.2%, 62.95%, and 64.6% at the respective resonance bands. A prototype of the proposed PCRM with 3 × 3 unit cells is fabricated to validate the simulated results. The experimental data agrees with the simulation results. The compactness, triple-band operation with a high PCR value of more than 92% makes use of the designed metasurface in wireless antenna-integrated applications at ISM and X-bands.


Assuntos
Eletricidade , Tecnologia sem Fio , Humanos , Simulação por Computador , Refração Ocular , Translocação Genética
14.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298414

RESUMO

This work presents the design and fabrication of a metamaterial-based stimulated dual band antenna on FR4 material (dielectric constant 4.3) to operate in Industrial, Scientific and Medical (ISM) and Radio-frequency Identification (RFID) applications. The antenna model had an overall dimension of 70 × 31 × 1.6 mm3 with etched T-slots and L-slots for dual band resonance. The main objective of this work was to enhance the gain performance characteristic at the selected dual band frequencies of 0.915 GHz and 2.45 GHz. Initially, it achieved a narrow bandwidth of 0.018 GHz with a gain of 1.53 dBi at a lower frequency, and 0.13 GHz of bandwidth featuring 4.49 dBi of gain at a higher frequency. The antenna provided an impedance bandwidth of 2% (0.905-0.923 GHz) and 5% (2.382-2.516 GHz) at two resonating frequencies. The antenna was integrated with a designed novel AMC structure to enhance the gain in CST Microwave Studio software with the finite integration method. The characteristic features of the AMC unit cell were observed at 0.915 GHz and 2.45 GHz frequencies and after antenna integration, the final prototype achieved a gain of 2.87 dBi at 0.915 GHz and 6.8 dBi at 2.45 GHz frequencies.


Assuntos
Dispositivo de Identificação por Radiofrequência , Tecnologia sem Fio , Desenho de Equipamento , Micro-Ondas
15.
J Clin Microbiol ; 59(2)2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33234589

RESUMO

Current commercially available methods for reliably detecting antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain expensive and inaccessible due to the need for whole-blood collection by highly trained phlebotomists using personal protective equipment (PPE). We have evaluated an antibody detection approach using the OraSure Technologies oral antibody collection device (OACD) and their proprietary SARS-CoV-2 total antibody detection enzyme-linked immunosorbent assay (ELISA). We found that the OraSure test for total antibody detection in oral fluid had comparable sensitivity and specificity to commercially available serum-based ELISAs for SARS-CoV-2 antibody detection while allowing for a more accessible form of specimen collection with the potential for self-collection.


Assuntos
Anticorpos Antivirais/análise , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Manejo de Espécimes/instrumentação , Teste Sorológico para COVID-19/instrumentação , Teste Sorológico para COVID-19/normas , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/análise , SARS-CoV-2/imunologia , Saliva/imunologia , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Manejo de Espécimes/normas
16.
Phys Chem Chem Phys ; 23(34): 18308-18313, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34269785

RESUMO

Understanding the mechanism responsible for the protein low-temperature crossover observed at T≈ 220 K can help us improve current cryopreservation technologies. This crossover is associated with changes in the dynamics of the system, such as in the mean-squared displacement, whereas experimental evidence of structural changes is sparse. Here we investigate hydrated lysozyme proteins by using a combination of wide-angle X-ray scattering and molecular dynamics (MD) simulations. Experimentally we suppress crystallization by accurate control of the protein hydration level, which allows access to temperatures down to T = 175 K. The experimental data indicate that the scattering intensity peak at Q = 1.54 Å-1, attributed to interatomic distances, exhibits temperature-dependent changes upon cooling. In the MD simulations it is possible to decompose the water and protein contributions and we observe that, while the protein component is nearly temperature independent, the hydration water peak shifts in a fashion similar to that of bulk water. The observed trends are analysed by using the water-water and water-protein radial distribution functions, which indicate changes in the local probability density of hydration water.


Assuntos
Temperatura Baixa , Simulação de Dinâmica Molecular , Proteínas/química , Água/química , Difração de Raios X , Conformação Proteica
17.
Curr Microbiol ; 79(1): 6, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34905096

RESUMO

Microorganisms due, to their immense metabolic diversity, have the potential to augment the uptake of iron and zinc in addition to other important nutrients in plants. In the present work, 129 different strains of endophytic bacteria were retrieved from stems and leaves of maize. Qualitative screening of these endophytes showed that 24.5% of these isolates were siderophore producers, while 14% could solubilize insoluble zinc compounds and 33% of them had phytase activity. Based on zinc solubilization efficiency and siderophore production ability, 10 isolates each from zinc solubilizers and siderophore producers were selected. Molecular identification indicated that the selected bacteria belonged to diverse genera Microbacterium, Pseudonocardia, Bacillus, Cellulosimicrobium, Staphylococcus, Luteimonas, Bordetella, Brevundimonas, Streptomyces, Cupriavidus, Sphingomonas, Ralstonia, Ochrobactrum, Conyzicola, Paenibacillus and Leifsonia. Quantitative analyses of Zn solubilization using Atomic absorption spectrophotometry (AAS) revealed that Microbacterium hydrothermale M10 and M. proteolyticum B2 were potential solubilizers of different forms of insoluble zinc compounds viz. ZnCO3 (56.63-89.88 ppm), ZnO (106.38-120.08 ppm) and ZnS (3.62-5.56 ppm). Similarly, quantitative estimation of siderophore production activity revealed two endophytes viz. Bacillus altitudinis C7 (97.25% siderophore units) and Pseudonocardia alni M29 (92.05% siderophore units) as potential siderophore producers. These endophytes with potential to produce siderophores and phytases and ability to solubilize zinc can be an important starting material for trials on field to improve Fe and Zn content in edible portion of food crops.


Assuntos
Cupriavidus , Endófitos , Biofortificação , Endófitos/genética , Micronutrientes , Raízes de Plantas , Zea mays
18.
J Am Chem Soc ; 142(2): 945-952, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31867949

RESUMO

Understanding the interfacial molecular structure of acidic aqueous solutions is important in the context of, e.g., atmospheric chemistry, biophysics, and electrochemistry. The hydration of the interfacial proton is necessarily different from that in the bulk, given the lower effective density of water at the interface, but has not yet been elucidated. Here, using surface-specific vibrational spectroscopy, we probe the response of interfacial protons at the water-air interface and reveal the interfacial proton continuum. Combined with spectral calculations based on ab initio molecular dynamics simulations, the proton at the water-air interface is shown to be well-hydrated, despite the limited availability of hydration water, with both Eigen and Zundel structures coexisting at the interface. Notwithstanding the interfacial hydrated proton exhibiting bulk-like structures, a substantial interfacial stabilization by -1.3 ± 0.2 kcal/mol is observed experimentally, in good agreement with our free energy calculations. The surface propensity of the proton can be attributed to the interaction between the hydrated proton and its counterion.

19.
Hemoglobin ; 44(6): 397-401, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33092414

RESUMO

Thalassemia is the most common congenital monogenic disorder in Bangladesh. Prenatal diagnosis (PND) and pregnation termination of an affected child is one of the best options to reduce the burden of thalassemic children. This article reports the results of DNA analyses of chorionic villus sampling (CVS) and amniocentesis of fetuses of mothers who came to the thalassemia center of Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh. DNA analysis was done by real-time polymerase chain reaction (qPCR) and Sanger sequencing. Maternal contamination was ruled out by variable number of tandem repeats (VNTRs). A total of 232 samples were analyzed. Hb E (HBB: c.79G>A)/ß-thalassemia (Hb E/ß-thal) was the most common type of thalassemia seen in 32 samples (13.79%) followed by ß-thal major (ß-TM) in 10 cases (4.31%). Molecular characterization of the most predominant mutation was IVS-I-5 (G>A) (HBB: c.92+5G>C). The analysis also revealed five rare mutations: IVS-II-654 (C>T) (HBB: c.316-197C>T), IVS-II-1 (G>A) (HBB: c.315+5G>A), codon 44 (-C) (HBB: c.135delC), -86 (C>A) (HBB: c.-136C>A) and codons 14/15 (+G) (HBB: c.45_46insG), which have not been reported previously in Bangladesh. This study provides important information for PND and will help in the development of similar diagnostic programs for other DNA centers in Bangladesh.


Assuntos
Mutação , Diagnóstico Pré-Natal , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Talassemia beta/diagnóstico , Talassemia beta/genética , Alelos , Bangladesh/epidemiologia , Feminino , Frequência do Gene , Loci Gênicos , Genótipo , Humanos , Masculino , Gravidez , Diagnóstico Pré-Natal/métodos , Talassemia alfa/epidemiologia , Talassemia beta/epidemiologia
20.
J Assoc Physicians India ; 68(11): 14-19, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33187030

RESUMO

BACKGROUND: Seroprevalence studies for COVID-19 evaluate the extent of undetected transmission in a defined community, with special significance among health care workers (HCW) owing to their greater exposure and potential to transmit. METHODS: A total of 1122 HCW (approximately 25% of the employees) of a large tertiary care hospital in India were recruited for this cross-sectional study. COVID PCR-positive HCW were excluded. Based on their risk-assessment, participants were grouped into three categories. A questionnaire was administered and they were tested for SARS-CoV-2-IgG antibodies using the chemiluminescence. RESULTS: The overall seroprevalence among workers was 11.94%, which included 19.85% in COVID units, 11.09% in non-COVID units, and 8% in administrative workers (p=0.007). Antibody prevalence was highest in the department of gastroenterology (11.94%), followed by oncology (10.53%), pathology (10.26%), emergency medicine (7.84%) and critical care medicine (7%). Housekeeping staff, food and beverage staff, lab assistants and technicians had higher seroprevalence rate than doctors and nurses (p < 0.0001). HCW with a history of BCG vaccination in childhood and those who received an adequate prophylactic dose of hydroxychloroquine (HCQ) had a lower seroprevalence as compared to those who did not (7.31% vs. 16.8% and 1.30% vs. 11.25% respectively). CONCLUSION: BCG vaccination, HCQ prophylaxis, and the job profile influence the seroprevalence rate in HCW. Seroprevalence rate and follow-up evaluation of its durability may help hospitals to triage their staff at risk, rationalize their placement, prioritize the use of PPE, thereby potentially reducing the risk.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus , COVID-19 , Criança , Estudos Transversais , Pessoal de Saúde , Humanos , Índia/epidemiologia , SARS-CoV-2 , Estudos Soroepidemiológicos , Centros de Atenção Terciária
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