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2.
Artigo em Inglês | MEDLINE | ID: mdl-38700134

RESUMO

This review presents a comprehensive examination of the contemporary landscape pertaining to latent tuberculosis infection (LTBI) diagnostics, with a particular emphasis on the global ramifications and the intricacies surrounding LTBI diagnosis and treatment. It accentuates the imperative of bolstering diagnostic, preventive, and treatment modalities for tuberculosis (TB) to fulfill the ambitious targets set forth by the World Health Organization aimed at reducing TB-related mortalities and the incidence of new TB cases. The document underscores the significance of addressing LTBI as a means of averting the progression to active TB, particularly in regions burdened with high TB prevalence, such as India. An in-depth analysis of the spectrum delineating latent and active TB disease is provided, elucidating the risk factors predisposing individuals with LTBI to progress towards active TB, including compromised immune functionality, concurrent HIV infection, and other immunosuppressive states. Furthermore, the challenges associated with LTBI diagnosis are elucidated, encompassing the absence of a definitive diagnostic assay, and the merits and demerits of tuberculin skin testing (TST) and interferon-γ release assays (IGRAs) are expounded upon. The document underscores the necessity of confronting these challenges and furnishes a meticulous examination of the advantages and limitations of TST and IGRAs, along with the intricacies involved in interpreting their outcomes across diverse demographics and settings. Additionally, attention is drawn towards the heritability of the interferon-γ response to mycobacterial antigens and the potential utility of antibodies in LTBI diagnosis.

3.
ACS Earth Space Chem ; 8(4): 630-653, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38654896

RESUMO

Colloid generation, stability, and transport are important processes that can significantly influence the fate and transport of nutrients and contaminants in environmental systems. Here, we critically review the existing literature on colloids in redox-dynamic environments and summarize the current state of knowledge regarding the mechanisms of colloid generation and the chemical controls over colloidal behavior in such environments. We also identify critical gaps, such as the lack of universally accepted cross-discipline definition and modeling infrastructure that hamper an in-depth understanding of colloid generation, behavior, and transport potential. We propose to go beyond a size-based operational definition of colloids and consider the functional differences between colloids and dissolved species. We argue that to predict colloidal transport in redox-dynamic environments, more empirical data are needed to parametrize and validate models. We propose that colloids are critical components of element budgets in redox-dynamic systems and must urgently be considered in field as well as lab experiments and reactive transport models. We intend to bring further clarity and openness in reporting colloidal measurements and fate to improve consistency. Additionally, we suggest a methodological toolbox for examining impacts of redox dynamics on colloids in field and lab experiments.

4.
Bioorg Chem ; 147: 107334, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38583251

RESUMO

Building upon our previous study on peptoid-based antibacterials which showed good activity against Gram-positive bacteria only, herein we report the synthesis of 34 dimeric peptoid compounds and the investigation of their activity against Gram-positive and Gram-negative pathogens. The newly designed peptoids feature a di-hydrophobic moiety incorporating phenyl, bromo-phenyl, and naphthyl groups, combined with variable lengths of cationic units such as amino and guanidine groups. The study also underscores the pivotal interplay between hydrophobicity and cationicity in optimizing efficacy against specific bacteria. The bromophenyl dimeric guanidinium peptoid compound 10j showed excellent activity against S. aureus 38 and E. coli K12 with MIC of 0.8 µg mL-1 and 6.2 µg mL-1, respectively. Further investigation into the mechanism of action revealed that the antibacterial effect might be attributed to the disruption of bacterial cell membranes, as suggested by tethered bilayer lipid membranes (tBLMs) and cytoplasmic membrane permeability studies. Notably, these promising antibacterial agents exhibited negligible toxicity against mammalian red blood cells. Additionally, the study explored the potential of 12 active compounds to disrupt established biofilms of S. aureus 38. The most effective biofilm disruptors were ethyl and octyl-naphthyl guanidinium peptoids (10c and 10 k). These compounds 10c and 10 k disrupted the established biofilms of S. aureus 38 with 51 % at 4x MIC (MIC = 17.6 µg mL-1 and 11.2 µg mL-1) and 56 %-58 % at 8x MIC (MIC = 35.2 µg mL-1 and 22.4 µg mL-1) respectively. Overall, this research contributes insights into the design principles of cationic dimeric peptoids and their antibacterial activity, with implications for the development of new antibacterial compounds.

5.
Chem Sci ; 15(16): 6095-6105, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38665536

RESUMO

The present study employs a blend of molecular dynamics simulations and a theoretical model to explore the potential disintegration mechanism of a matured Aß octamer, aiming to offer a strategy to combat Alzheimer's disease. We investigate local heating and crowding effects on Aß disintegration by selectively heating key Aß segments and varying the concentration of sodium dodecyl sulphate (SDS), respectively. Despite initiation of disruption, Aß aggregates resist complete disintegration during local heating due to rapid thermal energy distribution to the surrounding water. Conversely, although SDS molecules effectively inhibit Aß aggregation at higher concentration through micelle formation, they fail to completely disintegrate the aggregate due to the exceedingly high energy barrier. To address the sampling challenge posed by the formidable energy barrier, we have performed well-tempered metadynamics simulations. Simulations reveal a multi-step disintegration mechanism for the Aß octamer, suggesting a probable sequence: octamer → pentamer/hexamer ⇌ tetramer → monomer, with a rate-determining step constituting 45 kJ mol-1 barrier during the octamer to pentamer/hexamer transition. Additionally, we have proposed a novel two-state mean-field model based on Ising spins that offers an insight into the kinetics of the Aß growth process and external perturbation effects on disintegration. Thus, the current simulation study, coupled with the newly introduced mean-field model, offers an insight into the detailed mechanisms underlying the Aß aggregation process, guiding potential strategies for effective disintegration of Aß aggregates.

6.
Cells ; 13(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38667271

RESUMO

Even with the best infection control protocols in place, the risk of a hospital-acquired infection of the surface of an implanted device remains significant. A bacterial biofilm can form and has the potential to escape the host immune system and develop resistance to conventional antibiotics, ultimately causing the implant to fail, seriously impacting patient well-being. Here, we demonstrate a 4 log reduction in the infection rate by the common pathogen S. aureus of 3D-printed polyaryl ether ketone (PAEK) polymeric surfaces by covalently binding the antimicrobial peptide Mel4 to the surface using plasma immersion ion implantation (PIII) treatment. The surfaces with added texture created by 3D-printed processes such as fused deposition-modelled polyether ether ketone (PEEK) and selective laser-sintered polyether ketone (PEK) can be equally well protected as conventionally manufactured materials. Unbound Mel4 in solution at relevant concentrations is non-cytotoxic to osteoblastic cell line Saos-2. Mel4 in combination with PIII aids Saos-2 cells to attach to the surface, increasing the adhesion by 88% compared to untreated materials without Mel4. A reduction in mineralisation on the Mel4-containing surfaces relative to surfaces without peptide was found, attributed to the acellular portion of mineral deposition.


Assuntos
Peptídeos Antimicrobianos , Benzofenonas , Polímeros , Impressão Tridimensional , Próteses e Implantes , Staphylococcus aureus , Humanos , Staphylococcus aureus/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/metabolismo , Próteses e Implantes/efeitos adversos , Polímeros/química , Polímeros/farmacologia , Biofilmes/efeitos dos fármacos , Cetonas/química , Cetonas/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Propriedades de Superfície , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Ortopedia
7.
Int J Biol Macromol ; 268(Pt 2): 131823, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38677667

RESUMO

Chitosan, a versatile biopolymer, has gained recognition in the discipline of dental implantology due to possessing salient properties. This comprehensive review explores the potential of chitosan in dental implants, focusing on its biocompatibility, bioactivity, and the various chitosan-based materials that have been utilized for dental implant therapy. The review also highlights the importance of surface treatment in dental implants to enhance osseointegration and inhibit bacterial biofilm formation. Additionally, the chemical structure, properties, and sources of chitosan are described, along with its different structural forms. The characteristics of chitosan particularly color, molecular weight, viscosity, and degree of deacetylation are discussed about their influence on its applications. This review provides valuable insights into the promising utilization of polymeric chitosan in enhancing the success and functionality of dental implants. This study highlights the potential applications of chitosan in oral implantology. Chitosan possesses various advantageous properties, including muco-adhesiveness, hemostatic action, biocompatibility, biodegradability, bioactivity, and antibacterial and antifungal activities, which enhance its uses in dental implantology. However, it has limited aqueous solubility at the physiological pH, which sometimes restricts its biological application, but this problem can be overcome by using modified chitosan or chitosan derivatives, which have also shown encouraging results. Recent research suggests that chitosan may act as a promising material for coating titanium-based implants, improving osteointegration together with antibacterial properties.

8.
Plants (Basel) ; 13(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38674572

RESUMO

Salinity is one of the most significant abiotic stress that affects the growth and development of high-value tree species, including sandalwood, which can also be managed effectively on saline soils with the help of suitable host species. Therefore, the current investigation was conducted to understand the physiological processes and antioxidant mechanisms in sandalwood along the different salinity gradients to explore the host species that could support sandalwood growth in salt-affected agro-ecosystems. Sandalwood seedlings were grown with ten diverse host species with saline water irrigation gradients (ECiw~3, 6, and 9 dS m-1) and control (ECiw~0.82 dS m-1). Experimental findings indicate a decline in the chlorophyll content (13-33%), relative water content (3-23%), photosynthetic (27-61%) and transpiration rate (23-66%), water and osmotic potential (up to 137%), and ion dynamics (up to 61%) with increasing salinity levels. Conversely, the carotenoid content (23-43%), antioxidant activity (up to 285%), and membrane injury (82-205%) were enhanced with increasing salinity stress. Specifically, among the hosts, Dalbergia sissoo and Melia dubia showed a minimum reduction in chlorophyll content, relative water content, and plant water relation and gas exchange parameters of sandalwood plants. Surprisingly, most of the host tree species maintained K+/Na+ of sandalwood up to moderate water salinity of ECiw~6 dS m-1; however, a further increase in water salinity decreased the K+/Na+ ratio of sandalwood by many-fold. Salinity stress also enhanced the antioxidative enzyme activity, although the maximum increase was noted with host plants M. dubia, followed by D. sissoo and Azadirachta indica. Overall, the investigation concluded that sandalwood with the host D. sissoo can be successfully grown in nurseries using saline irrigation water and, with the host M. dubia, it can be grown using good quality irrigation water.

9.
Sci Total Environ ; 926: 171823, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38521261

RESUMO

The study shows how geology and tectonic activity affect the soil gas 222Rn concentration. The tectonically active zone, namely the Ghuttu region, which is located within the Himalayan seismic belt, was studied to decipher its impact on soil gas 222Rn concentrations. A soil gas 222Rn study was performed in the soil at a depth of 30 cm, and it varied from 426 ± 156 Bq m-3 to 24,057 ± 1110 Bq m-3 with an average of 5356.5 ± 1634.6 Bq m-3, and at 60 cm below the soil surface, the concentration varied from 1130 ± 416 Bq m-3 to 30,236 ± 1350 Bq m-3 with an average of 8928.5 ± 2039.5 Bq m-3. These concentrations vary in soil from -3.4 % to 437.3 % as the depth moves from 30 cm to 60 cm. The variation in uranium content also shows anomalies, and higher values of uranium content in the soil affect the radon concentration in the study area. The average soil gas 222Rn concentration in the Ghuttu window was found to be higher than that in its surrounding region. This is likely due to transportation from daughter products of uranium. 222Rn mass exhalation rate measurements were also carried out, and a weak correlation with the soil gas 222Rn concentration was observed. A significant variation in the mass exhalation rate was noticed in tectonically active areas. This study is vital to understanding the behavior of radon and uranium in tectonic regions.

10.
ACS Appl Mater Interfaces ; 16(12): 14704-14711, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38494603

RESUMO

Interfacial regions play a key role in determining the overall power conversion efficiency of thin film solar cells. However, the nanoscale investigation of thin film interfaces using conventional analytical tools is challenging due to a lack of required sensitivity and spatial resolution. Here, we surmount these obstacles using tip-enhanced Raman spectroscopy (TERS) and apply it to investigate the absorber (Sb2Se3) and buffer (CdS) layers interface in a Sb2Se3-based thin film solar cell. Hyperspectral TERS imaging with 10 nm spatial resolution reveals that the investigated interface between the absorber and buffer layers is far from uniform, as TERS analysis detects an intermixing of chemical compounds instead of a sharp demarcation between the CdS and Sb2Se3 layers. Intriguingly, this interface, comprising both Sb2Se3 and CdS compounds, exhibits an unexpectedly large thickness of 295 ± 70 nm attributable to the roughness of the Sb2Se3 layer. Furthermore, TERS measurements provide compelling evidence of CdS penetration into the Sb2Se3 layer, likely resulting from unwanted reactions on the absorber surface during chemical bath deposition. Notably, the coexistence of ZnO, which serves as the uppermost conducting layer, and CdS within the Sb2Se3-rich region has been experimentally confirmed for the first time. This study underscores TERS as a promising nanoscale technique to investigate thin film inorganic solar cell interfaces, offering novel insights into intricate interface structures and compound intermixing.

11.
Global Spine J ; : 21925682231167096, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453667

RESUMO

STUDY DESIGN: Narrative review. OBJECTIVE: The spine is the most common site of metastases, associated with decreased quality of life. Increase in metastatic spine tumour surgery (MSTS) has caused us to focus on the management of blood, as blood loss is a significant morbidity in these patients. However, blood transfusion is also not without its own risks, and hence this led to blood conservation strategies and implementation of a concept of patient blood management (PBM) in clinical practise focusing on these patients. METHODS: A narrative review was conducted and all studies that were related to blood management in metastatic spine disease as well as PBM surrounding this condition were included. RESULTS: A total of 64 studies were included in this review. We discussed a new concept of patient blood management in patients undergoing MSTS, with stratification to pre-operative and intra-operative factors, as well as anaesthesia and surgical considerations. The studies show that PBM and reduction in blood transfusion allows for reduced readmission rates, lower risks associated with blood transfusion, and lower morbidity for patients undergoing MSTS. CONCLUSION: Through this review, we highlight various pre-operative and intra-operative methods in the surgical and anaesthesia domains that can help with PBM. It is an important concept with the significant amount of blood loss expected from MSTS. LEVEL OF EVIDENCE: Not applicable.

12.
Cureus ; 16(2): e53843, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38465021

RESUMO

Nodular regenerative hyperplasia (NRH) and obliterative portal venopathy (OPV) are two causes of non-cirrhotic portal hypertension (NCPH), which is a vascular liver disease wherein clinical signs of portal hypertension (PHT), such as esophageal varices, ascites, and splenomegaly develop in the absence of cirrhosis and portal vein thrombosis. The etiology often remains unidentified, but herein we present the case of a 56-year-old male with NCPH and refractory ascites who underwent liver biopsy confirming NRH and OPV. Etiological workup revealed beta-2 glycoprotein-1 and anticardiolipin antibodies, concerning antiphospholipid syndrome (APS) despite no prior history of thrombosis. The patient underwent a transjugular intrahepatic portosystemic shunt (TIPS) procedure for his refractory ascites and was started on prophylactic anticoagulation owing to a concern for APS with clinical improvement in his ascites and shortness of breath. Pursuing TIPS earlier in the setting of refractory ascites, as well as offering anticoagulation therapy for patients with possible APS to prevent the development of potential thromboses, could be appropriate recommendations to prevent complications in the disease course. This case report highlights the need for further investigations on the etiologies, diagnosis pathways, and treatment options for NCPH.

13.
Polymers (Basel) ; 16(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38475272

RESUMO

The aim of this study was to evaluate the effect of cetylpyridinium chloride (CPC) addition on the antibacterial and surface hardness characteristics of two commercial resin-based dental composites (RBDCs). A total of two hundred and seventy (n = 270) specimens from Filtek Z250 Universal and Filtek Z350 XT flowable RBDCs were fabricated with the addition of CPC at 2 %wt and 4 %wt concentrations to assess their antibacterial activity using the agar diffusion test and direct contact inhibition test, and their surface hardness using the Vickers microhardness test after 1 day, 30 days, and 90 days of aging. A surface morphology analysis of the specimens was performed using a scanning electron microscope (SEM). The RBDCs that contained 2 %wt and 4 %wt CPC demonstrated significant antibacterial activity against Streptococcus mutans up to 90 days, with the highest activity observed for the 4 %wt concentration. Nevertheless, there was a reduction in antibacterial effectiveness over time. Moreover, compared to the control (0 %wt) and 2 %wt CPC groups, the universal RBDCs containing 4 %wt CPC exhibited a notable decrease in surface hardness, while all groups showed a decline in hardness over time. In conclusion, the satisfactory combination of the antibacterial effect and surface hardness property of RBDCs was revealed with the addition of a 2 %wt CPC concentration.

14.
BMJ Case Rep ; 17(3)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531558

RESUMO

We diagnosed a patient with dengue fever who developed acute onset of sensorimotor quadriparesis with bladder involvement, and facial nerve involvement. Despite initial negative results in routine investigations and cerebrospinal fluid analysis, spinal MRI confirmed longitudinally extensive transverse myelitis. The aetiological workup was negative, prompting an investigation into the presence of dengue in the cerebrospinal fluid, which returned positive. This case underscores the importance of considering rare neurological complications in dengue, the value of advanced diagnostic techniques and the potential effectiveness of tailored interventions in challenging cases.


Assuntos
Dengue , Mielite Transversa , Mielite , Humanos , Mielite Transversa/diagnóstico , Dengue/complicações , Imageamento por Ressonância Magnética/métodos , Quadriplegia/complicações , Nervo Facial , Mielite/complicações
15.
Cureus ; 16(1): e52709, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38384655

RESUMO

INTRODUCTION: Type 2 diabetes mellitus (T2DM) mainly results from the inability of muscle, fat, and liver cells to uptake glucose due to insulin resistance or deficiency of insulin production by the pancreas. Predisposition to T2DM may be due to environmental, hereditary, or both factors. Although there are many genes involved in causing T2DM, transcription factor 7-like-2 gene (TCF7L2) rs7903146 (C/T) single nucleotide polymorphism (SNP) found in genome-wide association studies (GWAS) is susceptible to T2DM. TCF7L2 is involved in pancreatic beta cell proliferation and differentiation via the Wnt signaling mechanism. OBJECTIVES: To find the genetic association of TCF7L2 rs7903146 (C/T) gene polymorphism in patients with T2DM. METHODS: A case-control study was conducted on 194 T2DM patients recruited from the endocrinology department at Indira Gandhi Institute of Medical Sciences, Patna, and 180 non-diabetic healthy controls that were age and sex-matched with the patients. All clinical examination and biochemical investigations like glycosylated hemoglobin (HbA1c), total cholesterol, triglycerides, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol; and determination of TCF7L2 gene polymorphism by allele-specific polymerase chain reaction (AS-PCR) were carried out for each subject. RESULTS:  The T allele of the rs7903146 (C/T) SNP was associated with a two-fold higher risk of T2DM and the heterozygous genotype (CT) with a 1.96 times higher risk. CONCLUSION: There is a high association of this SNP with the development of T2DM in the eastern Indian population. Serial monitoring of HbA1c should be done in an individual having this type of polymorphism for early detection of T2DM to prevent future complications.

16.
Cont Lens Anterior Eye ; 47(2): 102124, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341309

RESUMO

BACKGROUND: Ocular infections caused by antibiotic-resistant pathogens can result in partial or complete vision loss. The development of pan-resistant microbial strains poses a significant challenge for clinicians as there are limited antimicrobial options available. Synthetic peptoids, which are sequence-specific oligo-N-substituted glycines, offer potential as alternative antimicrobial agents to target multidrug-resistant bacteria. METHODS: The antimicrobial activity of synthesised peptoids against multidrug-resistant (MDR) ocular pathogens was evaluated using the microbroth dilution method. Hemolytic propensity was assessed using mammalian erythrocytes. Peptoids were also incubated with proteolytic enzymes, after which their minimum inhibitory activity against bacteria was re-evaluated. RESULTS: Several alkylated and brominated peptoids showed good inhibitory activity against multidrug-resistant Pseudomonas aeruginosa strains at concentrations of ≤15 µg mL-1 (≤12 µM). Similarly, most brominated compounds inhibited the growth of methicillin-resistant Staphylococcus aureus at 1.9 to 15 µg mL-1 (12 µM). The N-terminally alkylated peptoids caused less toxicity to erythrocytes. The peptoid denoted as TM5 had a high therapeutic index, being non-toxic to either erythrocytes or corneal epithelial cells, even at 15 to 22 times its MIC. Additionally, the peptoids were resistant to protease activity. CONCLUSIONS: Peptoids studied here demonstrated potent activity against various multidrug-resistant ocular pathogens. Their properties make them promising candidates for controlling vision-related morbidity associated with eye infections by antibiotic-resistant strains.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Peptoides , Animais , Humanos , Peptoides/farmacologia , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Mamíferos
17.
Angew Chem Int Ed Engl ; 63(19): e202318682, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38407535

RESUMO

Gaining mechanistic understanding of oxygen activation on metal surfaces is a topical area of research in surface science. However, direct investigation of on-surface oxidation processes at the nanoscale and the empirical validation of oxygen activation pathways remain challenging for the conventional analytical tools. In this study, we applied tip-enhanced Raman spectroscopy (TERS) to gain mechanistic insights into oxygen activation on bulk Au(111) surface. Specifically, oxidation of 4-aminothiophenol (4-ATP) to 4-nitrothiophenol (4-NTP) on Au(111) surface was investigated using hyperspectral TERS imaging. Nanoscale TERS images revealed a markedly higher oxidation efficiency in disordered 4-ATP adlayers compared to the ordered adlayers signifying that the oxidation of 4-ATP molecules proceeds via interaction with the on-surface oxidative species. These results were further validated via direct oxidation of the 4-ATP adlayers with H2O2 solution. Finally, TERS measurements of oxidized 4-ATP adlayers in the presence of H2O18 provided the first empirical evidence for the generation of oxidative species on bulk Au(111) surface via water-mediated activation of molecular oxygen. This study expands our mechanistic understanding of oxidation chemistry on bulk Au surface by elucidating the oxygen activation pathway.

18.
J Phycol ; 60(2): 387-408, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38342971

RESUMO

Five cyanobacterial strains exhibiting Nostoc-like morphology were sampled from the biodiversity hotspots of the northeast region of India and characterized using a polyphasic approach. Molecular and phylogenetic analysis using the 16S rRNA gene indicated that the strains belonged to the genera Amazonocrinis and Dendronalium. In the present investigation, the 16S rRNA gene phylogeny clearly demarcated two separate clades of Amazonocrinis. The strain MEG8-PS clustered along with Amazonocrinis nigriterrae CENA67, which is the type strain of the genus. The other three strains ASM11-PS, RAN-4C-PS, and NP-KLS-5A-PS clustered in a different clade that was phylogenetically distinct from the Amazonocrinis sensu stricto clade. Interestingly, while the 16S rRNA gene phylogeny exhibited two separate clusters, the 16S-23S ITS region analysis did not provide strong support for the phylogenetic observation. Subsequent analyses raised questions regarding the resolving power of the 16S-23S ITS region at the genera level and the associated complexities in cyanobacterial taxonomy. Through this study, we describe a novel genus Ahomia to accommodate the members clustering outside the Amazonocrinis sensu stricto clade. In addition, we describe five novel species, Ahomia kamrupensis, Ahomia purpurea, Ahomia soli, Amazonocrinis meghalayensis, and Dendronalium spirale, in accordance with the International Code of Nomenclature for algae, fungi, and plants (ICN). Apart from further enriching the genera Amazonocrinis and Dendronalium, the current study helps to resolve the taxonomic complexities revolving around the genus Amazonocrinis and aims to attract researchers to the continued exploration of the tropical and subtropical cyanobacteria for interesting taxa and lineages.


Assuntos
Comportamento Exploratório , Nostoc , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Nostoc/genética , Biodiversidade , Índia
19.
Curr Med Imaging ; 20: 1-13, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389343

RESUMO

BACKGROUND: Modern medical imaging modalities used by clinicians have many applications in the diagnosis of complicated diseases. These imaging technologies reveal the internal anatomy and physiology of the body. The fundamental idea behind medical image fusion is to increase the image's global and local contrast, enhance the visual impact, and change its format so that it is better suited for computer processing or human viewing while preventing noise magnification and accomplishing excellent real-time performance. OBJECTIVE: The top goal is to combine data from various modal images (CT/MRI and MR-T1/MR-T2) into a solitary image that, to the greatest degree possible, retains the key characteristics (prominent features) of the source images. METHODS: The clinical accuracy of medical issues is compromised because innumerable classical fusion methods struggle to conserve all the prominent features of the original images. Furthermore, complex implementation, high computation time, and more memory requirements are key problems of transform domain methods. With the purpose of solving these problems, this research suggests a fusion framework for multimodal medical images that makes use of a multi-scale edge-preserving filter and visual saliency detection. The source images are decomposed using a two-scale edge-preserving filter into base and detail layers. Base layers are combined using the addition fusion rule, while detail layers are fused using weight maps constructed using the maximum symmetric surround saliency detection algorithm. RESULTS: The resultant image constructed by the presumed method has improved objective evaluation metrics than other classical methods, as well as unhindered edge contour, more global contrast, and no ringing effect or artifacts. CONCLUSION: The methodology offers a dominant and symbiotic arsenal of clinical symptomatic, therapeutic, and biomedical research competencies that have the prospective to considerably strengthen medical practice and biological understanding.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética , Humanos , Estudos Prospectivos
20.
Diagnostics (Basel) ; 14(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38201417

RESUMO

Metal artifact reduction (MAR) algorithms are commonly used in computed tomography (CT) scans where metal implants are involved. However, MAR algorithms also have the potential to create new artifacts in reconstructed images. We present a case of a screw pseudofracture due to MAR on CT.

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