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1.
BMC Biol ; 21(1): 29, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755285

RESUMO

BACKGROUND: Worldwide wheat production is under constant threat by fast-evolving fungal pathogens. In the last decades, wheat breeding for disease resistance heavily relied on the introgression of chromosomal segments from related species as genetic sources of new resistance. The Pm8 resistance gene against the powdery mildew disease has been introgressed from rye into wheat as part of a large 1BL.1RS chromosomal translocation encompassing multiple disease resistance genes and yield components. Due to its high agronomic value, this translocation has seen continuous global use since the 1960s on large growth areas, even after Pm8 resistance was overcome by the powdery mildew pathogen. The long-term use of Pm8 at a global scale provided the unique opportunity to study the consequences of such extensive resistance gene application on pathogen evolution. RESULTS: Using genome-wide association studies in a population of wheat mildew isolates, we identified the avirulence effector AvrPm8 specifically recognized by Pm8. Haplovariant mining in a global mildew population covering all major wheat growing areas of the world revealed 17 virulent haplotypes of the AvrPm8 gene that grouped into two functional categories. The first one comprised amino acid polymorphisms at a single position along the AvrPm8 protein, which we confirmed to be crucial for the recognition by Pm8. The second category consisted of numerous destructive mutations to the AvrPm8 open reading frame such as disruptions of the start codon, gene truncations, gene deletions, and interference with mRNA splicing. With the exception of a single, likely ancient, gain-of-virulence mutation found in mildew isolates around the world, all AvrPm8 virulence haplotypes were found in geographically restricted regions, indicating that they occurred recently as a consequence of the frequent Pm8 use. CONCLUSIONS: In this study, we show that the broad and prolonged use of the Pm8 gene in wheat production worldwide resulted in a multitude of gain-of-virulence mechanisms affecting the AvrPm8 gene in the wheat powdery mildew pathogen. Based on our findings, we conclude that both standing genetic variation as well as locally occurring new mutations contributed to the global breakdown of the Pm8 resistance gene introgression.


Assuntos
Ascomicetos , Triticum , Triticum/genética , Triticum/microbiologia , Resistência à Doença/genética , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Ascomicetos/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
2.
Nano Lett ; 21(20): 8595-8601, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34644094

RESUMO

Polarization-sensitive optical coherence tomography (PS-OCT) reveals the subsurface microstructure of biological tissue and provides information regarding the polarization state of light backscattered from tissue. Complementing OCT's structural signal with molecular imaging requires strategies to simultaneously detect multiple exogenous contrast agents with high specificity in tissue. Specific detection of molecular probes enables the parallel visualization of physiological, cellular, and molecular processes. Here we demonstrate that, by combining PS-OCT and spectral contrast (SC)-OCT measurements, we can distinguish signatures of different gold nanobipyramids (GNBPs) in lymphatic vessels from the surrounding tissue and blood vessels in live mouse models. This technique could well be extended to other anisotropic nanoparticle-based OCT contrast agents and presents significant progress toward enabling OCT molecular imaging.


Assuntos
Nanopartículas , Tomografia de Coerência Óptica , Animais , Modelos Animais de Doenças , Ouro , Camundongos
3.
Entropy (Basel) ; 24(1)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35052120

RESUMO

The underlying mechanism determining the size of a particular cell is one of the fundamental unknowns in cell biology. Here, using a new approach that could be used for most of unicellular species, we show that the protein synthesis and cell size are interconnected biophysically and that protein synthesis may be the chief mechanism in establishing size limitations of unicellular organisms. This result is obtained based on the free energy balance equation of protein synthesis and the second law of thermodynamics. Our calculations show that protein synthesis involves a considerable amount of entropy reduction due to polymerization of amino acids depending on the cytoplasmic volume of the cell. The amount of entropy reduction will increase with cell growth and eventually makes the free energy variations of the protein synthesis positive (that is, forbidden thermodynamically). Within the limits of the second law of thermodynamics we propose a framework to estimate the optimal cell size at division.

4.
Med J Islam Repub Iran ; 36: 70, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36128269

RESUMO

Background: Urolithiasis is a common, sever, painful, and costly disease with a high probability of relapse. This study was performed to compare the effect of Polycitra-K containing potassium citrate and Bicitra containing sodium citrate in the treatment of kidney stones in children who referred to Hazrat Masoumeh hospital in Qom. Methods: This double-blind randomized clinical trial study was carried out on 176 patients aged between 5 and 18 years old with kidney stones, hypocitraturia, and negative urine who referred to Hazrat Masoumeh hospital in Qom (Iran). Patients were divided into 2 groups of treatment (a dose of 1 mL/kg or 1-1.5 mg/ kg Polycitra-K) and control (Bicitra in the same dose). The results of kidney ureter bladder X ray (KUB ) was followed and the 2 groups were compared. The chi-square test or the Fisher exact test was used to analyze qualitative values in the treated groups. Results: Regarding bladder stones, there was a significant difference between the 2 treatment groups (p = 0.025), in which16 patients (18.2%) in the Polycitrat-K group and 29 patients (33%) in the Bicitra group had bladder stones. With respect to stone passage, 58 patients (65.9%) in the Polycitra-K group and 36 patients (40.9%) in the Bicitra group were recorded. Conclusion: Oral Polycitrat-K is an effective preferential supplement against kidney stones in children due to urine alkalization, but the results of our study showed that both Polycitrat-K and Bicitra drugs have similar effects as therapeutic agents. Registration code in the Iranian Registry of Clinical Trials: IRCT20190619043945N1.

5.
Med J Islam Repub Iran ; 36: 115, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36447537

RESUMO

Background: Three-dimensional models are used to guide residents and physicians in accessing specific anatomical areas and types of fractures and better diagnosis of anomalies. These models are useful for illuminating complex anatomical areas, such as orbit, especially limited space with sensitive access. The aim of this study was to design a three-dimensional visualization educational modeling for ophthalmology residents' training. Methods: This study is a product-oriented application that uses radiological images of anatomy, anomalies, and orbital fractures based on actual CT scans of patients. These CT scans were carefully selected from the Picture Archiving and Communication System of Ghaem Hospital of Mashhad University of Medical Sciences. Results: To produce twelve 3D models, the CT scan files were converted to 3D printer output. Then, the models were presented to residents at a training session by an ophthalmologist. These models created all major fractures associated with the orbit area and most disorders, anomalies of this area and several normal anatomical. The features of 3D models were mentioned. The strengths and weaknesses of the educational modeling, the level of satisfaction with the use of three-dimensional models, suggestions and criticisms were assessed qualitatively by the residents. Satisfaction was reported 100% by residents. Suggestions for future 3D models were presented, and the only criticism was fear of exams and grades. Conclusion: Real-size 3D modeling help to understand the spatial and mental imagery of anatomy and orbital pathology and to touch different anatomical areas creates a clear image in the minds of residents, especially in the orbit.

6.
J Neurovirol ; 27(2): 348-353, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33650073

RESUMO

This study was designed to evaluate whether severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can directly target the central nervous system (CNS). We present four patients suffering from the loss of consciousness and seizure during the clinical course of COVID-19 infection. In addition to positive nasopharyngeal swab tests, SARS-CoV-2 has been detected in their cerebrospinal fluid. This report indicates the neuroinvasive potential of SARS-CoV-2, suggesting the ability of this virus to spread from the respiratory tract to the CNS.


Assuntos
COVID-19/complicações , Líquido Cefalorraquidiano/virologia , SARS-CoV-2/isolamento & purificação , Convulsões/virologia , Síndrome Respiratória Aguda Grave/virologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070493

RESUMO

5-Aminolevulinic acid (5-ALA) is a naturally occurring non-proteinogenic amino acid, which contributes to the diagnosis and therapeutic approaches of various cancers, including glioblastoma (GBM). In the present study, we aimed to investigate whether 5-ALA exerted cytotoxic effects on GBM cells. We assessed cell viability, apoptosis rate, mRNA expressions of various apoptosis-related genes, generation of reactive oxygen species (ROS), and migration ability of the human U-87 malignant GBM cell line (U87MG) treated with 5-ALA at different doses. The half-maximal inhibitory concentration of 5-ALA on U87MG cells was 500 µg/mL after 7 days; 5-ALA was not toxic for human optic cells and NIH-3T3 cells at this concentration. The application of 5-ALA led to a significant increase in apoptotic cells, enhancement of Bax and p53 expressions, reduction in Bcl-2 expression, and an increase in ROS generation. Furthermore, the application of 5-ALA increased the accumulation of U87MG cells in the SUB-G1 population, decreased the expression of cyclin D1, and reduced the migration ability of U87MG cells. Our data indicate the potential cytotoxic effects of 5-ALA on U87MG cells. Further studies are required to determine the spectrum of the antitumor activity of 5-ALA on GBM.


Assuntos
Ácido Aminolevulínico/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-30397053

RESUMO

While carbapenem resistance in Gram-negative bacteria is mainly due to the production of efficient carbapenemases, ß-lactamases with a narrower spectrum may also contribute to resistance when combined with additional mechanisms. OXA-10-type class D ß-lactamases, previously shown to be weak carbapenemases, could represent such a case. In this study, two novel OXA-10 variants were identified as the sole carbapenem-hydrolyzing enzymes in meropenem-resistant enterobacteria isolated from hospital wastewater and found by next-generation sequencing to express additional ß-lactam resistance mechanisms. The new variants, OXA-655 and OXA-656, were carried by two related IncQ1 broad-host-range plasmids. Compared to the sequence of OXA-10, they both harbored a Thr26Met substitution, with OXA-655 also bearing a leucine instead of a valine in position 117 of the SAV catalytic motif. Susceptibility profiling of laboratory strains replicating the natural blaOXA plasmids and of recombinant clones expressing OXA-10 and the novel variants in an isogenic background indicated that OXA-655 is a more efficient carbapenemase. The carbapenemase activity of OXA-655 is due to the Val117Leu substitution, as shown by steady-state kinetic experiments, where the kcat of meropenem hydrolysis was increased 4-fold. In contrast, OXA-655 had no activity toward oxyimino-ß-lactams, while its catalytic efficiency against oxacillin was significantly reduced. Moreover, the Val117Leu variant was more efficient against temocillin and cefoxitin. Molecular dynamics indicated that Val117Leu affects the position 117-Leu155 interaction, leading to structural shifts in the active site that may alter carbapenem alignment. The evolutionary potential of OXA-10 enzymes toward carbapenem hydrolysis combined with their spread by promiscuous plasmids indicates that they may pose a future clinical threat.


Assuntos
Antibacterianos/química , Enterobacteriaceae/genética , Resistência beta-Lactâmica/genética , beta-Lactamases/química , Substituição de Aminoácidos , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Sequência de Bases , Domínio Catalítico , Cefoxitina/química , Cefoxitina/metabolismo , Cefoxitina/farmacologia , Clonagem Molecular , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Expressão Gênica , Hospitais , Humanos , Hidrólise , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Meropeném/química , Meropeném/metabolismo , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , Modelos Moleculares , Oxacilina/química , Oxacilina/metabolismo , Oxacilina/farmacologia , Penicilinas/química , Penicilinas/metabolismo , Penicilinas/farmacologia , Plasmídeos/química , Plasmídeos/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Águas Residuárias/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
9.
J Med Virol ; 91(2): 296-307, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30192395

RESUMO

The ORFs of both native and codon-optimized E7 genes were successfully fused to SPusp45 signal peptide and expressed by a nisin-controlled gene expression system in the NZ9000 strains of Lactococcus lactis. Recombinant strains were confirmed by Western blot analysis. To measure immune responses against the E7 antigen, specific-pathogen-free C57BL/6 mice were inoculated with L lactis harboring pNZ8123-rE7 by oral gavage. Then, specific antibodies and cytokines were measured by enzyme-linked immunosorbent assay and enzyme-linked immunospot assay, respectively. Oral administration of L lactis strains expressing rE7 elicited the highest levels of E7-specific antibody and greatest numbers of E7-specific CD4+ T helper and CD8+ T cell precursors. Our outcomes indicated that the HPV-16 E7 specific IL-2- and IFN-γ-secreting T cells in antigen-stimulated splenocytes and intestinal mucosal lymphocytes were significantly higher than the control groups. Our data also demonstrated that mice vaccinated with recombinant L lactis were able to generate potent protective effects against challenge with the E7-expressing tumor cell line (TC-1). Moreover, L lactis containing pNZ8123-HPV16-optiE7 showed strong therapeutic antitumor effects against established tumors in vivo. These findings demonstrate that recombinant L lactis induce both humoral and cellular immune responses in mice and are therefore recommended for therapeutic treatments in humans after oral administration.


Assuntos
Portadores de Fármacos/administração & dosagem , Lactococcus lactis/genética , Proteínas E7 de Papillomavirus/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Administração Oral , Animais , Anticorpos Antivirais/sangue , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , ELISPOT , Feminino , Camundongos Endogâmicos C57BL , Proteínas E7 de Papillomavirus/genética , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/genética , Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
10.
Graefes Arch Clin Exp Ophthalmol ; 256(1): 209-218, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28986670

RESUMO

PURPOSE: Intravenously administered erythropoietin (EPO) was firstly commenced (phase 1) in patients with indirect traumatic optic neuropathy (TON) by this group in 2011. It was re-tested by another group (phase 2) in 2014. This multicenter clinical trial was designed to compare its effect with intravenous steroid and observation. METHODS: Included were TON patients ≥5 years of age and with trauma-treatment interval of ≤3 weeks. Follow-up visits were set at 1, 2, 3, 7, 14, 30, and at least 90 days after treatment. EPO and methylprednisolone were infused intravenously every day for three consecutive days. Primary outcome measure was change in the best corrected visual acuity (BCVA). Secondary outcomes included change in color vision and relative afferent pupillary defect (RAPD), side effects, and factors affecting the final visual improvement. RESULTS: Out of 120 patients, 100 (EPO: 69, steroid: 15, observation: 16) were finally included. All three groups showed a significant improvement of BCVA which was not significantly different between the groups (adjusted for pretreatment BCVA). Color vision was significantly improved in the EPO group. Late treatment (>3 days) (odds ratio = 2.53) and initial BCVA of NLP (odds ratio = 5.74) significantly worsened visual recovery. No side effect was observed in any group. CONCLUSION: EPO, steroid, and observation showed a significant improvement of BCVA in patients with TON. Initial BCVA of NLP and late treatment (>3 days) were significant risk factors for visual improvement.


Assuntos
Eritropoetina/administração & dosagem , Metilprednisolona/administração & dosagem , Doenças do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/complicações , Acuidade Visual , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Visão de Cores , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/administração & dosagem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/etiologia , Traumatismos do Nervo Óptico/diagnóstico , Resultado do Tratamento , Adulto Jovem
11.
Am J Physiol Heart Circ Physiol ; 313(6): H1249-H1260, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28778909

RESUMO

The intrinsic contraction of collecting lymphatic vessels serves as a pumping system to propel lymph against hydrostatic pressure gradients as it returns interstitial fluid to the venous circulation. In the present study, we proposed and validated that the maximum opposing outflow pressure along a chain of lymphangions at which flow can be achieved increases with the length of chain. Using minimally invasive near-infrared imaging to measure the effective pumping pressure at various locations in the rat tail, we demonstrated increases in pumping pressure along the length of the tail. Computational simulations based on a microstructurally motivated model of a chain of lymphangions informed from biaxial testing of isolated vessels was used to provide insights into the pumping mechanisms responsible for the pressure increases observed in vivo. These models suggest that the number of lymphangions in the chain and smooth muscle cell force generation play a significant role in determining the maximum outflow pressure, whereas the frequency of contraction has no effect. In vivo administration of nitric oxide attenuated lymphatic contraction, subsequently lowering the effective pumping pressure. Computational simulations suggest that the reduction in contractile strength of smooth muscle cells in the presence of nitric oxide can account for the reductions in outflow pressure observed along the lymphangion chain in vivo. Thus, combining modeling with multiple measurements of lymphatic pumping pressure provides a method for approximating intrinsic lymphatic muscle activity noninvasively in vivo while also providing insights into factors that determine the extent that a lymphangion chain can transport fluid against an adverse pressure gradient. NEW & NOTEWORTHY Here, we report the first minimally invasive in vivo measurements of the relationship between lymphangion chain length and lymphatic pumping pressure. We also provide the first in vivo validation of lumped parameter models of lymphangion chains previously developed through data obtained from isolated vessel testing.


Assuntos
Simulação por Computador , Vasos Linfáticos/fisiologia , Contração Muscular , Animais , Vasos Linfáticos/diagnóstico por imagem , Masculino , Miócitos de Músculo Liso/fisiologia , Pressão , Ratos , Ratos Sprague-Dawley , Espectroscopia de Luz Próxima ao Infravermelho
12.
Microb Pathog ; 110: 554-560, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28754267

RESUMO

The present work was aimed at investigating the expression and optimization of a human papillomavirus (HPV) type 16 gene encoding oncoprotein E7 in Lactococcus lactis. We genetically engineered Lactococcus lactis using nisin-controlled gene expression (NICE) system pNZ8148 to express the native and codon optimized E7 oncogenes isolated from Iranian HPV-16. The results of optimizing fermentation showed, the concentration of produced protein was expressively improved by 10 ng/mL nisin after 3.5, and 4 h induction for NZ9000 harboring the codon-optimized, and native E7 respectively. Furthermore the recombinant NZ9000 strains expressed rE7 by maximum value of 4.7 (Codon-optimized), and 1.82 µg/mL (Native) in static flask experiments at initial glucose concentrations of 50 and 75 g/L respectively. The rE7 yield was further enriched in batch fermenter experiments using controlled pH. Thus, the overall production of rE7 under optimized conditions accumulated in the cytoplasm to nearly 33.25 µg/mL by L. lactis NZ9000 containing codon-optimized E7, which was over ∼2.7-fold higher compared to the NZ9000 having native E7 strain (12.01 µg/mL). Accordingly, the maximum biomass production was calculated 4.87, and 1.51 g/L respectively.


Assuntos
Expressão Gênica , Lactococcus lactis/metabolismo , Proteínas E7 de Papillomavirus/biossíntese , Proteínas Recombinantes/biossíntese , Reatores Biológicos/microbiologia , Meios de Cultura/química , Genes Reguladores , Glucose/metabolismo , Irã (Geográfico) , Lactococcus lactis/genética , Lactococcus lactis/crescimento & desenvolvimento , Nisina/genética , Proteínas E7 de Papillomavirus/genética , Proteínas Recombinantes/genética , Ativação Transcricional
13.
Orbit ; 33(2): 91-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24354541

RESUMO

PURPOSE: To compare open and closed methods of the frontalis suspension operation with a silicone rod in the treatment of congenital blepharoptosis. METHODS: Forty-four cases with unilateral or bilateral congenital ptosis with a poor levator function of < 4 mm were divided randomly into two groups. Each group underwent an eyelid crease incision operation (open) or a supralash stab incision (closed). Ptosis was measured by the difference between the upper eyelid margin reflex distance (MRD) of the affected eyelids of the unilateral and bilateral cases. Frequent follow-up examinations were performed up to 12 months post-surgery. RESULTS: Associated ophthalmologic findings showed that amblyopia, strabismus, wound discharge and knot dehiscence problems were present in 36.6%, 27.3%, 8.5% and 8.5% of the patients, respectively. There was no significant difference between the abovementioned associated ophthalmic findings of the two operative methods studied (P = 0.37). The difference in the surgical methods and MRD 3, 6 and 12 months after operation did not reach statistical significance. Similar results for good MRD (3 < MRD < 5) were found in closed (54.5%, 12/22) and open (54.5%, 12/22) methods, while 40.9% (9/22) and 45.5% (10/22) of cases were attributed to the under correction group in the closed and open methods, respectively. In bilaterally operated cases, MRD was more symmetrical than in unilaterally operated eyes. The symmetry of MRD and the eyelid crease was more prevalent in the open technique group. CONCLUSIONS: The frontalis sling operation using a silicone rod exhibited better results, in terms of symmetry, in the open technique in comparison to the closed method.


Assuntos
Blefaroplastia/métodos , Blefaroptose/cirurgia , Pálpebras/cirurgia , Músculos Oculomotores/cirurgia , Implantação de Prótese , Elastômeros de Silicone , Blefaroptose/congênito , Blefaroptose/fisiopatologia , Criança , Movimentos Oculares/fisiologia , Pálpebras/fisiopatologia , Feminino , Humanos , Masculino , Resultado do Tratamento , Acuidade Visual/fisiologia
14.
APMIS ; 132(2): 94-99, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37965984

RESUMO

The aim of this study was to investigate antimicrobial susceptibilities and genomic characteristics of mupirocin-resistant MRSA isolates in Stockholm, Sweden. In total, 44 non-duplicate mupirocin-resistant MRSA isolates detected in Stockholm during 2010-2022 were investigated. Antimicrobial susceptibility testing was performed using broth microdilution method and further tested for high-level mupirocin-resistance (MuH) and rifampicin by Etest®. All isolates were subjected to whole genome sequencing. 41 isolates presented MuH with MICs ≥1024 mg/L whilst three isolates displayed low-level mupirocin resistance (MuL). mupA-gene was detected in all MuH isolates. Point mutations in ileS gene leading to N213D and V588F were identified in the three MuL isolates. Mutation in rpoB (H481N) was detected in a rifampicin-resistant isolate. Among the isolates, 15 multi-locus sequence types (MLST) were identified, with the four most common sequence types (ST22, ST72, ST8, and ST125) accounting for 66% of the isolates. Mupirocin-resistant MRSA in Stockholm was uncommon, with a percentage of <0.5% among MRSA cases during 2010-2022. In the present study, most mupirocin-resistant isolates were MuH and mupA-positive, predominantly linked to ST22 or ST72 isolates. MuL-resistance was associated with a point mutation in the IleS protein. A multidrug-resistant ST1-MRSA-IV strain was resistant to both mupirocin and rifampicin.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Mupirocina/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Antibacterianos/farmacologia , Rifampina/farmacologia , Tipagem de Sequências Multilocus/métodos , Suécia/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Testes de Sensibilidade Microbiana , Genômica
15.
Artigo em Inglês | MEDLINE | ID: mdl-38692743

RESUMO

The lymphatic system plays a crucial role in maintaining tissue fluid balance, immune surveillance, and the transport of lipids and macromolecules. Lymph is absorbed by initial lymphatics and then driven through lymph nodes and to the blood circulation by the contraction of collecting lymphatic vessels. Intraluminal valves in collecting lymphatic vessels ensure the unidirectional flow of lymph centrally. The lymphatic muscle cells that invest in collecting lymphatic vessels impart energy to propel lymph against hydrostatic pressure gradients and gravity. A variety of mechanical and biochemical stimuli modulate the contractile activity of lymphatic vessels. This review focuses on the recent advances in our understanding of the mechanisms involved in regulating and collecting lymphatic vessel pumping in normal tissues and the association between lymphatic pumping, infection, inflammatory disease states, and lymphedema.

16.
Int J Antimicrob Agents ; : 107256, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925228

RESUMO

Herein, we investigated decreased susceptibility (DS; MICs 0.25-4 mg/L) and resistance (R; MICs >4 mg/L) to aztreonam-avibactam (ATM-AVI). Contemporary non-replicate clinical isolates of carbapenemase-producing Escherichia coli (n=90) (CP-EC) and ESBL-producing E. coli (n=12) (EP-EC) was used. CP-EC belonged to 25 distinct sequence types (STs) and all EP-EC belonged to ST405. All strains were isolated through 2019-2022 at the Karolinska University Laboratory, Stockholm, Sweden. ATM-AVI MICs were determined with broth microdilution and the EUCAST epidemiological cutoff value of 0.125 mg/L was used to define the wildtype (WT). Whole genome sequences (Illumina) were analyzed for detecting of resistance determinants among WT vs non-WT isolates. Among 102 isolates, 40 (39%) and 62 (61%) were WT and non-WT respectively. Among non-WT isolates 20 were R and 42 were DS. Resistance was observed among 14/47 NDM-producers, 5/43 OXA-48 group producers, and 1/12 EP-EC. DS was observed among 29/47 NDM, 13/43 OXA-48 group, and 3/12 EP-EC. Resistant isolates predominantly belonged to ST405 followed by STs 410, 361, 167, 617, and 1284. Presence of PBP3 inserts (YRIK/YRIN) were observed in 20/20 and presence of CMY-42 in 5/20 resistant isolates. Several mutations in the ftsI (encoding PBP3) and regulatory genes of outer membrane proteins (OmpC and OmpF) and efflux pumps (AcrAB-TolC) were detected. A ≥2-fold reduction in MICs were observed among 20/20 vs 7/20 isolates tested in the presence of the membrane permeabilizer PMBN and efflux inhibitor PAßN, respectively. In conclusion, resistance to ATM-AVI is a result of interplay of various determinants, including target alterations, deactivating enzymes, and decreased permeability.

17.
bioRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38712181

RESUMO

Despite significant strides in lymphatic system imaging, the timely diagnosis of lymphatic disorders remains elusive. One main cause for this is the absence of standardized, quantitative methods for real-time analysis of lymphatic contractility. Here, we address this unmet need by combining near-infrared lymphangiography imaging with an innovative analytical workflow. We combined data acquisition, signal processing, and statistical analysis to integrate traditional peak and-valley with advanced wavelet time-frequency analyses. Decision theory was used to evaluate the primary drivers of attributable variance in lymphangiography measurements to generate a strategy for optimizing the number of repeat measurements needed per subject to increase measurement reliability. This approach not only offers detailed insights into lymphatic pumping behaviors across species, sex and age, but also significantly boosts the reliability of these measurements by incorporating multiple regions of interest and evaluating the lymphatic system under various gravitational loads. By addressing the critical need for improved imaging and quantification methods, our study offers a new standard approach for the imaging and analysis of lymphatic function that can improve our understanding, diagnosis, and treatment of lymphatic diseases. The results highlight the importance of comprehensive data acquisition strategies to fully capture the dynamic behavior of the lymphatic system.

18.
Lancet Microbe ; 5(4): e355-e365, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432233

RESUMO

BACKGROUND: Antimicrobials cause perturbations in the composition and diversity of the host microbiome. We aimed to compare gut microbiome perturbations caused by oral tebipenem pivoxil hydrobromide (a novel carbapenem) and by amoxicillin-clavulanic acid (an orally administered ß-lactam-ß-lactam inhibitor combination widely used in clinical practice). METHODS: We did a phase 1, single-centre, randomised, parallel-group, active-control trial to evaluate the effect of tebipenem pivoxil hydrobromide on the human gut microbiota. Healthy participants aged 18 years or older with no documented illnesses during recruitment were enrolled at Karolinska University Hospital (Stockholm, Sweden). Study participants were stratified by sex and block-randomised in a 1:1 ratio to treatment with either tebipenem pivoxil hydrobromide (600 mg orally every 8 h) or amoxicillin-clavulanic acid (500 mg amoxicillin and 125 mg clavulanic acid orally every 8 h). The study included 10 days of treatment (days 1-10) and four follow-up visits (days 14, 21, 90, and 180). The trial was open-label for clinical investigators and patients, but masked for microbiology investigators. Faecal samples were collected at all visits. Sequencing of 16S rDNA was used to measure the diversity metrics, and quantitative culture to quantify selected taxa. The primary outcomes were changes in the α and ß diversity and log count of colony-forming units for selected taxa between samples compared with baseline (day 1), and whether any changes reverted during the follow-up period. The analyses were done in the intention-to-treat population. This study was registered with ClinicalTrials.gov (NCT04376554). FINDINGS: The study was conducted between Jan 23, 2020, and April 6, 2021. 49 volunteers were screened for eligibility, among whom 30 evaluable participants (14 men and 16 women) were assigned: 15 (50%) to the tebipenem pivoxil hydrobromide group and 15 (50%) to the amoxicillin-clavulanic acid group. Baseline characteristics were similar between groups. Complete follow-up was available for all participants, and all participants except one completed treatment as assigned. The diversity metrics showed significant changes from baseline during the treatment period. Significant decreases in richness were observed on days 4-10 (p≤0·0011) in the amoxicillin-clavulanic acid group and on days 4-14 (p≤0·0019) in the tebipenem pivoxil hydrobromide group. Similarly, evenness was significantly decreased during treatment in the amoxicillin-clavulanic acid group (day 4, p=0·030) and the tebipenem pivoxil hydrobromide group (days 4-10, p<0·0001) compared with baseline. Quantitative cultures showed significant decreases in Enterobacterales (days 4-7, p≤0·0030), Enterococcus spp (days 4-14, p=0·025 to p<0·0001), Bifidobacterium spp (days 2-4, p≤0·026), and Bacteroides spp (days 4-10, p≤0·030) in the tebipenem pivoxil hydrobromide group. Similarly, in amoxicillin-clavulanic acid recipients, significant changes were observed in Enterobacterales (days 4-10, p≤0·048), Bifidobacterium spp (days 2-4, p≤0·013), and Lactobacillus spp (days 2-4, p≤0·020). Samples from the follow-up period were not significantly different from those at baseline in ß diversity analysis (PERMANOVA, p>0·99). By the end of the study, no significant change was observed compared with baseline in either group. There were no deaths or severe adverse events. INTERPRETATION: The impact of tebipenem pivoxil hydrobromide on the gut microbiome was similar to that of amoxicillin-clavulanic acid. The safety of antibiotic use with regard to the microbiome should be given attention, as dysbiosis is associated with health and disease. FUNDING: Spero Therapeutics.


Assuntos
Carbapenêmicos , Microbioma Gastrointestinal , Masculino , Adulto , Humanos , Feminino , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Suécia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Monobactamas
19.
bioRxiv ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37781599

RESUMO

Surgical removal of lymph nodes (LNs) to prevent metastatic recurrence, including sentinel lymph node biopsy (SLNB) and completion lymph node dissection (CLND), are performed in routine practice. However, it remains controversial whether removing LNs which are critical for adaptive immune responses impairs immune checkpoint blockade (ICB) efficacy. Here, our retrospective analysis demonstrated that stage III melanoma patients retain robust response to anti-PD1 inhibition after CLND. Using orthotopic murine mammary carcinoma and melanoma models, we show that responses to ICB persist in mice after TDLN resection. Mechanistically, after TDLN resection, antigen can be re-directed to distant LNs, which extends the responsiveness to ICB. Strikingly, by evaluating head and neck cancer patients treated by neoadjuvant durvalumab and irradiation, we show that distant LNs (metastases-free) remain reactive in ICB responders after tumor and disease-related LN resection, hence, persistent anti-cancer immune reactions in distant LNs. Additionally, after TDLN dissection in murine models, ICB delivered to distant LNs generated greater survival benefit, compared to systemic administration. In complete responders, anti-tumor immune memory induced by ICB was systemic rather than confined within lymphoid organs. Based on these findings, we constructed a computational model to predict free antigen trafficking in patients that will undergo LN dissection.

20.
J Curr Ophthalmol ; 35(2): 105-109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38250492

RESUMO

Purpose: To review the principles and different techniques of minimally invasive procedures in strabismus surgery. Methods: This is a narrative review on minimally invasive procedures in strabismus surgery including general aspects and different new modifications on conventional strabismus surgery. We reviewed 24 articles published between 1993 and 2020. Results: Minimal invasive procedures could be categorized into two subsets: one which minimizes conjunctival opening size and another which minimizes the muscle manipulations. Different conjunctival approaches have been introduced, such as Cul-de-sac and minimally invasive strabismus surgery incisions. Furthermore, there are different techniques for extraocular muscle weakening, strengthening, and transposition, such as mini-tenotomy, plication, mini-plication, Nishida, and modified Nishida procedures. Moreover, there are some techniques for handling strabismus in heavy eyes with high myopia and using adjustable sutures for strabismus correction. Conclusions: Minimally invasive procedures in strabismus surgery consist of surgical procedures that minimize tissue disruption, speed up rehabilitation, and often ultimate better outcomes. These techniques could be replaced traditional methods to reduce conjunctival and lid swelling in the direct postoperative period.

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