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1.
Am J Ophthalmol Case Rep ; 35: 102001, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38827998

RESUMO

Purpose: To report a case of bilateral acute macular neuroretinopathy (AMN) associated with COVID-19 infection presenting with central scotoma. Observation: A 26-year-old female presented with a chief complaint of bilateral central scotomas for the last seven days. She had a history of fever over the past ten days, and RT-PCR test for COVID-19 was positive on the second day of fever. She had been vaccinated against COVID-19 eight months prior. Her best corrected visual acuity was 6/6 in both eyes on the Snellen chart. Dilated fundus evaluation revealed subtle bilateral perifoveal grey macular lesions. Optical coherence tomography (OCT) demonstrated focal hyperreflectivity at the level of the outer nuclear and plexiform layer consistent with bilateral AMN. Near-infrared reflectance (NIR) and red-free (RF) imaging showed large, confluent hyporeflective lesions in the right eye and discrete petaloid lesions with apices pointing toward the fovea in the left eye. OCT angiography (OCTA) revealed decreased flow signal at the level of the deep capillary plexus (DCP) and choriocapillaris (CC) in both eyes. Automated visual field testing (Humprey Field Analyzer (HFA) 24-2) revealed bilateral central scotoma with depression of adjacent points. After two weeks, the patient had depressed visual fields on HFA 10-2. At two months of final follow-up, OCT macula, NIR and RF images revealed resolving AMN lesions in both eyes. OCTA showed an increase in perfusion at the level of the DCP. There was a decrease in scotoma density on HFA 10-2, suggestive of resolving AMN. Conclusion and importance: AMN with central scotoma as presenting feature of COVID-19 is rare. Fundus findings may be very subtle in AMN, but NIR and RF imaging delineate the lesions well. OCT, NIR imaging, OCTA and HFA 10-2 can be used to assess the clinical course of AMN.

2.
iScience ; 27(2): 108867, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38318389

RESUMO

The detrimental effects of high-dose ionizing radiation on human health are well-known, but the influence of sex differences on the delayed effects of acute radiation exposure (DEARE) remains unclear. Here, we conducted six-month animal experiments using escalating radiation doses (7-9 Gy) on male and female C57BL/6 mice. The results show that female mice exhibited greater resistance to radiation, showing increased survival at six months post-total body irradiation. LD50/30 (lethal dose expected to cause 50% lethality in 30 days) for female mice is 8.08 Gy, while for male mice it is 7.76 Gy. DEARE causes time- and sex-dependent dysregulation of microRNA expression, processing enzymes, and the HOTAIR regulatory pathway. Differential regulation of molecular patterns associated with growth, development, apoptosis, and cancer is also observed in male and female mice. These findings shed light on the molecular basis of age and sex differences in DEARE response and emphasize the importance of personalized medicine for mitigating radiation-induced injuries and diseases.

3.
Radiat Res ; 201(5): 406-417, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38319684

RESUMO

The purpose of this investigation was to characterize the natural history of a murine total-abdominal-irradiation exposure model to measure gastrointestinal acute radiation injury. Male CD2F1 mice at 12 to 15 weeks old received total-abdominal irradiation using 4-MV linear accelerator X-rays doses of 0, 11, 13.5, 15, 15.75 and 16.5 Gy (2.75 Gy/min). Daily cage-side (i.e., in the animal housing room) observations of clinical signs and symptoms including body weights on all animals were measured up to 10 days after exposure. Jejunum tissues from cohorts of mice were collected at 1, 3, 7 and 10 days after exposure and radiation injury was assessed by histopathological analyses. Results showed time- and dose-dependent loss of body weight [for example at 7 days: 0.66 (±0.80) % loss for 0 Gy, 6.40 (±0.76) % loss at 11 Gy, 9.43 (±2.06) % loss at 13.5 Gy, 23.53 (± 1.91) % loss at 15 Gy, 29.97 (±1.16) % loss at 15.75 Gy, and 31.79 (±0.76) % loss at 16.5 Gy]. Negligible clinical signs and symptoms, except body weight changes, of radiation injury were observed up to 10 days after irradiation with doses of 11 to 15 Gy. Progressive increases in the severity of clinical signs and symptoms were found after irradiation with doses >15 Gy. Jejunum histology showed a progressive dose-dependent increase in injury. For example, at 7 days postirradiation, the percent of crypts, compared to controls, decreased to 82.3 (±9.5), 69.2 (±12.3), 45.4 (±11.9), 18.0 (±3.4), and 11.5 (± 1.8) with increases in doses from 11 to 16.5 Gy. A mucosal injury scoring system was used that mainly focused on changes in villus morphology damage (i.e., subepithelial spaces near the tips of the villi with capillary congestion, significant epithelial lifting along the length of the villi with a few denuded villus tips). Peak levels of total-abdominal irradiation induced effects on the mucosal injury score were seen 7 days after irradiation for doses ≥15 Gy, with a trend to show a decline after 7 days. A murine multiple-parameter gastrointestinal acute-radiation syndrome severity-scoring system was established based on clinical signs and symptoms that included measures of appearance (i.e., hunched and/or fluffed fur), respiratory rate, general (i.e., decreased mobility) and provoked behavior (i.e., subdued response to stimulation), weight loss, and feces/diarrhea score combined with jejunum mucosal-injury grade score. In summary, the natural-history radio-response for murine partial-body irradiation exposures is important for establishing a well-characterized radiation model system; here we established a multiple-parameter gastrointestinal acute-radiation syndrome severity-scoring system that provides a radiation injury gastrointestinal tissue-based assessment utility.


Assuntos
Síndrome Aguda da Radiação , Animais , Camundongos , Masculino , Síndrome Aguda da Radiação/patologia , Síndrome Aguda da Radiação/etiologia , Relação Dose-Resposta à Radiação , Jejuno/efeitos da radiação , Jejuno/patologia , Modelos Animais de Doenças , Índice de Gravidade de Doença , Trato Gastrointestinal/efeitos da radiação , Trato Gastrointestinal/patologia , Peso Corporal/efeitos da radiação , Lesões Experimentais por Radiação/patologia
4.
Radiat Res ; 201(5): 460-470, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38376474

RESUMO

With the current volatile geopolitical climate, the threat of nuclear assault is high. Exposure to ionizing radiation from either nuclear incidents or radiological accidents often lead to major harmful consequences to human health. Depending on the absorbed dose, the symptoms of the acute radiation syndrome and delayed effects of acute radiation exposure (DEARE) can appear within hours, weeks to months. The lung is a relatively radiosensitive organ with manifestation of radiation pneumonitis as an acute effect, followed by apparent fibrosis in weeks or even months. A recently developed, first-of-its-kind murine model for partial-body irradiation (PBI) injury, which can be used to test potential countermeasures against multi-organ damage such as gastrointestinal (GI) tract and lungs was used for irradiation, with 2.5% bone marrow spared (BM2.5-PBI) from radiation exposure. Long-term damage to lungs from radiation was evaluated using µ-CT scans, pulmonary function testing, histopathological parameters and molecular biomarkers. Pulmonary fibrosis was detected by ground glass opacity observed in µ-CT scans of male and female C57BL/6J mice 6-7 months after BM2.5-PBI. Lung mechanics assessments pertaining to peripheral airways suggested fibrotic lungs with stiffer parenchymal lung tissue and reduced inspiratory capacity in irradiated animals 6-7 months after BM2.5-PBI. Histopathological evaluation of the irradiated lungs revealed presence of focal and diffuse pleural, and parenchymal inflammatory and fibrotic lesions. Fibrosis was confirmed by elevated levels of collagen when compared to lungs of age-matched naïve mice. These findings were validated by findings of elevated levels of pro-fibrotic biomarkers and reduction in anti-inflammatory proteins. In conclusion, a long-term model for radiation-induced pulmonary fibrosis was established, and countermeasures could be screened in this model for survival and protection/mitigation or recovery from radiation-induced pulmonary damage.


Assuntos
Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Fibrose Pulmonar , Animais , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , Camundongos , Masculino , Feminino , Pulmão/efeitos da radiação , Pulmão/patologia , Pneumonite por Radiação/patologia , Pneumonite por Radiação/etiologia , Lesões Experimentais por Radiação/patologia , Lesões Experimentais por Radiação/etiologia
5.
Radiat Res ; 201(5): 449-459, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38373011

RESUMO

In the current geopolitical climate there is an unmet need to identify and develop prophylactic radiation countermeasures, particularly to ensure the well-being of warfighters and first responders that may be required to perform on radiation-contaminated fields for operational or rescue missions. Currently, no countermeasures have been approved by the U.S. FDA for prophylactic administration. Here we report on the efficacious nature of FSL-1 (toll-like receptor 2/6 agonist) and the protection from acute radiation syndrome (ARS) in a murine total-body irradiation (TBI) model. A single dose of FSL-1 was administered subcutaneously in mice. The safety of the compound was assessed in non-irradiated animals, the efficacy of the compound was assessed in animals exposed to TBI in the AFRRI Co-60 facility, the dose of FSL-1 was optimized, and common hematological parameters [complete blood cell (CBC), cytokines, and bone marrow progenitor cells] were assessed. Animals were monitored up to 60 days after exposure and radiation-induced damage was evaluated. FSL-1 was shown to be non-toxic when administered to non-irradiated mice at doses up to 3 mg/kg. The window of efficacy was determined to be 24 h prior to 24 h after TBI. FSL-1 administration resulted in significantly increased survival when administered either 24 h prior to or 24 h after exposure to supralethal doses of TBI. The optimal dose of FSL-1 administration was determined to be 1.5 mg/kg when administered prior to irradiation. Finally, FSL-1 protected the hematopoietic system (recovery of CBC and bone marrow CFU). Taken together, the effects of increased survival and accelerated recovery of hematological parameters suggests that FSL-1 should be developed as a novel radiation countermeasure for soldiers and civilians, which can be used either before or after irradiation in the aftermath of a radiological or nuclear event.


Assuntos
Síndrome Aguda da Radiação , Modelos Animais de Doenças , Oligopeptídeos , Irradiação Corporal Total , Animais , Camundongos , Síndrome Aguda da Radiação/tratamento farmacológico , Síndrome Aguda da Radiação/patologia , Hematopoese/efeitos dos fármacos , Hematopoese/efeitos da radiação , Camundongos Endogâmicos C57BL , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Protetores contra Radiação/farmacologia , Protetores contra Radiação/uso terapêutico , Irradiação Corporal Total/efeitos adversos
6.
Radiat Res ; 201(1): 19-34, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38014611

RESUMO

The goal of this study was to establish a model of partial-body irradiation (PBI) sparing 2.5% of the bone marrow (BM2.5-PBI) that accurately recapitulates radiological/nuclear exposure scenarios. Here we have reported a model which produces gastrointestinal (GI) damage utilizing a clinical linear accelerator (LINAC) with precise dosimetry, which can be used to develop medical countermeasures (MCM) for GI acute radiation syndrome (ARS) under the FDA animal rule. The PBI model (1 hind leg spared) was developed in male and female C57BL/6 mice that received radiation doses ranging from 12-17 Gy with no supportive care. GI pathophysiology was assessed by crypt cell loss and correlated with peak lethality between days 4 and 10 after PBI. The radiation dose resulting in 50% mortality in 30 days (LD50/30) was determined by probit analysis. Differential blood cell counts in peripheral blood, colony forming units (CFU) in bone marrow, and sternal megakaryocytes were analyzed between days 1-30, to assess the extent of hematopoietic ARS (H-ARS) injury. Radiation-induced GI damage was also assessed by measuring: 1. bacterial load (16S rRNA) by RT-PCR on days 4 and 7 after PBI in liver, spleen and jejunum, 2. liposaccharide binding protein (LBP) levels in liver, and 3. fluorescein isothiocyanate (FITC)-dextran, E-selectin, sP-selectin, VEGF, FGF-2, MMP-9, citrulline, and serum amyloid A (SAA) levels in serum. The LD50/30 of male mice was 14.3 Gy (95% confidence interval 14.1-14.7 Gy) and of female mice was 14.5 Gy (95% confidence interval 14.3-14.7 Gy). Secondary endpoints included loss of viable crypts, higher bacterial loads in spleen and liver, higher LBP in liver, increased FITC-dextran and SAA levels, and decreased levels of citrulline and endothelial biomarkers in serum. The BM2.5-PBI model, developed for the first time with precise dosimetry, showed acute radiation-induced GI damage that is correlated with lethality, as well as a response to various markers of inflammation and vascular damage. Sex-specific differences were observed with respect to radiation dose response. Currently, no MCM is available as a mitigator for GI-ARS. This BM2.5-PBI mouse model can be regarded as the first high-throughput PBI model with precise dosimetry for developing MCMs for GI-ARS under the FDA animal rule.


Assuntos
Síndrome Aguda da Radiação , Masculino , Feminino , Camundongos , Animais , Citrulina , RNA Ribossômico 16S , Camundongos Endogâmicos C57BL , Radiometria
7.
Microbiol Spectr ; : e0141923, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37655898

RESUMO

Indigenous white-rot fungal isolates Schizophyllum commune, Phanerochaete chrysosporium, Ganoderma racenaceum, and Lentinus squarrosulus, demonstrating the ability to depolymerize lignin of the crop residues, were studied for their potential to produce ligninolytic enzymes using modified production media under conditions of limiting and excess nitrogen for higher enzymatic expressions. Secretome-rich media on the investigation confirmed the successful production of lignin-depolymerizing enzymes, viz. laccase, lignin peroxidase, manganese peroxidase, and versatile peroxidase. Production of laccases and peroxidases was statistically significant in nitrogen-limiting media with and without the substrate, across all white-rot fungal cultures at 95% confidence interval. Nitrogen-limiting media with the substrate on analysis extracellularly expressed 99.27 U of laccase and 68.48 U of manganese peroxidase in Schizophyllum commune, while 195.14 U of lignin peroxidase was produced by Phanerochaete chrysosporium. Lentinus squarrosulus expressed 455.34 U of laccase and 357.13 U of versatile peroxidase with 250.09 U of laccase and 206.95 U of manganese peroxidase produced by Ganoderma racenaceum for every milliliter of the media used. Nitrogen-limiting media triggered the production of laccase during the initial stages of growth while the expression of peroxidases was predominant at a later stage. Also, this media evinced increased enzymatic yields with low biomass content compared to nitrogen-excess conditions. The extant study confirmed the positive influence of nitrogen-limiting media in the efficient production of ligninolytic enzymes and their suggestive degradation potential for environmental pollutants, making these enzymes a safe, clean alternative to the use of chemicals and the media to be effective for large-scale production of ligninolytic enzymes. IMPORTANCE Lignin on account of its high abundance, complex polymeric structure, and biochemical properties is identified as a promising candidate in renewable energy and bioproduct manufacturing. However, depolymerization of lignin remains a major challenge in lignin utilization, entailing the employment of harsh treatments representing not only an environmental concern but also a waste of economic potential. Developing an alternative green technology to minimize this impact is imperative. Methods using enzymes to depolymerize lignin are the focus of recent studies. Current research work emphasized the efficient expression of the major lignin-depolymerizing enzymes: laccases, lignin peroxidases, manganese peroxidases, and versatile peroxidases from native isolates of white-rot fungus for several biotechnological applications as well as treatment of crop residues for use as ruminant feed in improving productivity. The importance of nitrogen in augmenting the expression of lignin-depolymerizing enzymes and providing a media recipe for the cost-effective production of ligninolytic enzymes is highlighted.

8.
Sci Rep ; 13(1): 15211, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709916

RESUMO

Thrombopoietin (TPO) is the primary regulator of platelet generation and a stimulator of multilineage hematopoietic recovery following exposure to total body irradiation (TBI). JNJ­26366821, a novel PEGylated TPO mimetic peptide, stimulates platelet production without developing neutralizing antibodies or causing any adverse effects. Administration of a single dose of JNJ­26366821 demonstrated its efficacy as a prophylactic countermeasure in various mouse strains (males CD2F1, C3H/HeN, and male and female C57BL/6J) exposed to Co-60 gamma TBI. A dose dependent survival efficacy of JNJ­26366821 (- 24 h) was identified in male CD2F1 mice exposed to a supralethal dose of radiation. A single dose of JNJ­26366821 administered 24, 12, or 2 h pre-radiation resulted in 100% survival from a lethal dose of TBI with a dose reduction factor of 1.36. There was significantly accelerated recovery from radiation-induced peripheral blood neutropenia and thrombocytopenia in animals pre-treated with JNJ­26366821. The drug also increased bone marrow cellularity and megakaryocytes, accelerated multi-lineage hematopoietic recovery, and alleviated radiation-induced soluble markers of bone marrow aplasia and endothelial damage. These results indicate that JNJ­26366821 is a promising prophylactic radiation countermeasure for hematopoietic acute radiation syndrome with a broad window for medical management in a radiological or nuclear event.


Assuntos
Síndrome Aguda da Radiação , Neutropenia , Feminino , Masculino , Animais , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Trombopoetina/farmacologia , Síndrome Aguda da Radiação/tratamento farmacológico , Síndrome Aguda da Radiação/prevenção & controle , Polietilenoglicóis/farmacologia
9.
Antioxidants (Basel) ; 12(7)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37507957

RESUMO

The development of safe, orally available, and effective prophylactic countermeasures to protect our warfighters is an unmet need because there is no such FDA-approved countermeasure available for use. Th 1-Propanethiol, 3-(methylamino)-2-((methylamino)methyl) (PrC-210), a synthetic small molecule, is a member of a new family of aminothiols designed to reduce toxicity while scavenging reactive oxygen species (ROS). Our study investigated the protective role of a single oral administration of PrC-210 against radiation-induced hematopoietic and intestinal injury in mice. Pre-treatment with PrC-210 significantly improved the survival of mice exposed to a lethal dose of radiation. Our findings indicated that the radioprotective properties of PrC-210 are achieved by accelerating the recovery of the hematopoietic system, stimulating bone marrow progenitor cells, and ameliorating additional biomarkers of hematopoietic injury. PrC-210 pre-treatment reduced intestinal injury in mice exposed to a lethal dose of radiation by restoring jejunal crypts and villi, reducing translocation of bacteria to the spleen, maintaining citrulline levels, and reducing the sepsis marker serum amyloid A (SAA) in serum. Finally, PrC-210 pre-treatment led to a significant reduction (~10 fold) of Nos2 expression (inducible nitric oxide) in the spleen and decreased oxidative stress by enhancing the antioxidant defense system. These data support the further development of PrC-210 to receive approval from the FDA to protect warfighters and first responders from exposure to the harmful effects of ionizing radiation.

10.
Indian J Ophthalmol ; 71(6): 2500-2503, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37322670

RESUMO

Purpose: Glaucoma is the second leading cause of blindness worldwide, affecting more than 64 million people aged 40-80. The best way to manage primary open-angle glaucoma (POAG) is by lowering the intraocular pressure (IOP). Netarsudil is a Rho kinase inhibitor, the only class of antiglaucoma medications that reorganizes the extracellular matrix to improve the aqueous outflow through the trabecular pathway. Methods: An open-label, real-world, multicentric, observation-based 3-month study was performed for assessing the safety and ocular hypotensive efficacy of netarsudil ophthalmic solution (0.02% w/v) in patients with elevated IOP. Patients were given netarsudil ophthalmic solution (0.02% w/v) as a first-line therapy. Diurnal IOP measurements, best-corrected visual acuity, and adverse event assessments were recorded at each of the five visits (Day-1: screening day and first dosing day; subsequent observations were taken at 2 weeks, 4 weeks, 6 weeks, and 3 months). Results: Four hundred and sixty-nine patients from 39 centers throughout India completed the study. The mean IOP at baseline of the affected eyes was 24.84 ± 6.39 mmHg (mean ± standard deviation). After the first dose, the IOP was measured after 2, 4, and 6 weeks, with the final measurement taken at 3 months. The percentage reduction in IOP in glaucoma patients after 3 months of once-daily netarsudil 0.02% w/v solution use was 33.34%. The adverse effects experienced by patients were not severe in the majority of cases. Some adverse effects observed were redness, irritation, itching, and others, but only a small number of patients experienced severe reactions, as reported in a decreasing order: redness > irritation > watering > itching > stinging > blurring. Conclusion: We found that netarsudil 0.02% w/v solution monotherapy when used as the first-line treatment in primary open-angle glaucoma and ocular hypertension was both safe and effective.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Glaucoma de Ângulo Aberto , Glaucoma , Hipertensão Ocular , Humanos , Soluções Oftálmicas , Hipertensão Ocular/diagnóstico , Glaucoma/tratamento farmacológico , Pressão Intraocular , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Resultado do Tratamento
11.
Cytogenet Genome Res ; 163(3-4): 187-196, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37348469

RESUMO

There is an increased threat of exposure to ionizing radiation; in the event of such exposure, the availability of medical countermeasures will be vital to ensure the protection of the population. Effective countermeasures should be efficacious across a varied population and most importantly amongst both males and females. Radiation research must be conducted in animal models which act as a surrogate for the human response. Here, we identify differences in survival in male and female C57BL/6 in both a total body irradiation (TBI) model using the Armed Forces Radiobiology Research Institute (AFRRI) 60Co source and a partial body irradiation (PBI) model using the AFRRI Linear Accelerator (LINAC) with 4 MV photons and 2.5% bone marrow shielding. In both models, we observed a higher degree of radioresistance in female animals and a corresponding radiosensitivity in males. One striking difference in male and female rodents is body size/weight and we investigated the role of pre-irradiation body weight on survivability for animals irradiated at the same dose of irradiation (8 Gy TBI, 14 Gy PBI). We found that weight does not influence survival in the TBI model and that heavier males but lighter females have increased survival in the PBI model. This incongruence in survival amongst the sexes should be taken into consideration in the course of developing radiation countermeasures for response to a mass casualty incident.


Assuntos
Radiação Ionizante , Humanos , Feminino , Masculino , Animais , Camundongos , Modelos Animais
12.
Toxics ; 12(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276718

RESUMO

IL-18 has been shown to play important roles in response to total body irradiation. However, homogenous total body irradiation is not a realistic model to reflect the radiation exposure in a real nuclear event. To further study the roles of IL-18 in a real nuclear scenario, we developed a mouse partial body irradiation with 5% bone marrow sparing (PBI/BM5) model to mimic the inhomogeneous radiation exposure. We established the dose response curves of PBI/BM5 using different radiation doses ranging from 12 to 16 Gy. Using the PBI/BM5 model, we showed that IL-18 knockout mice were significantly more radiation resistant than the wild-type mice at 14.73 Gy. We further studied the hematopoietic changes using a complete blood count, bone marrow colony-forming assays, and serum cytokine assays on the mice exposed to PBI/BM5 with IL-18BP treatment and wild-type/IL-18 knockout mice. In conclusion, our data suggest that IL-18 plays important roles in mouse survival in a realistic nuclear exposure model, potentially through the IL-18/IFNγ pathway.

13.
Mol Ther Nucleic Acids ; 30: 569-584, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36457703

RESUMO

Risks of radiation exposure necessitate the development of radioprophylactic drugs. We have reported the efficacy of CDX-301, a recombinantly developed human protein form of Fms-related tyrosine kinase 3 ligand (Flt3L), as a radioprophylactic and radiomitigatory agent. Here, we performed global microRNA profiling to further understand the mechanism of action of CDX-301. We find that CDX-301 administration 24 h prior to total body irradiation prevents radiation-induced dysregulation of microRNA biogenesis and expression in murine serum and spleen samples in a time- and tissue-dependent manner. Further analysis shows that activation of the HOTAIR regulatory pathway has a prominent function in radiation-induced injury responses, which is inhibited by pre-treatment with CDX-301. Moreover, CDX-301 attenuates radiation-induced dysregulation of several cellular functions such as inflammatory and immune responses. In corroboration, we also find that pre-treatment with CDX-301 restores the expression of bone marrow aplasia markers and inflammatory cytokines and growth factors, as well as the expression of genes associated with MAP kinase and TGF-ß pathways that are altered by radiation. Our findings provide new insights into CDX-301-mediated molecular and cellular mechanisms and point to a possible novel radioprotective drug for the prevention of irradiation-induced injury and hematopoietic acute radiation syndrome.

14.
Genes (Basel) ; 13(10)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36292639

RESUMO

Acute Radiation Syndrome (ARS) is a syndrome involving damage to multiple organs caused by exposure to a high dose of ionizing radiation over a short period of time; even low doses of radiation damage the radiosensitive hematopoietic system and causes H-ARS. PLacenta eXpanded (PLX)-R18 is a 3D-expanded placenta-derived stromal cell product designated for the treatment of hematological disorders. These cells have been shown in vitro to secrete hematopoietic proteins, to stimulate colony formation, and to induce bone marrow migration. Previous studies in mice showed that PLX-R18 cells responded to radiation-induced hematopoietic failure by transiently secreting hematopoiesis related proteins to enhance reconstitution of the hematopoietic system. We assessed the potential effect of prophylactic PLX-R18 treatment on H-ARS. PLX-R18 cells were administered intramuscularly to C57BL/6 mice, −1 and 3 days after (LD70/30) total body irradiation. PLX R18 treatment significantly increased survival after irradiation (p < 0.0005). In addition, peripheral blood and bone marrow (BM) cellularity were monitored at several time points up to 30 days. PLX-R18 treatment significantly increased the number of colony-forming hematopoietic progenitors in the femoral BM and significantly raised peripheral blood cellularity. PLX-R18 administration attenuated biomarkers of bone marrow aplasia (EPO, FLT3L), sepsis (SAA), and systemic inflammation (sP-selectin and E-selectin) and attenuated radiation-induced inflammatory cytokines/chemokines and growth factors, including G-CSF, MIP-1a, MIP-1b, IL-2, IL-6 and MCP-1, In addition, PLX-R18 also ameliorated radiation-induced upregulation of pAKT. Taken together, prophylactic PLX-R18 administration may serve as a protection measure, mitigating bone marrow failure symptoms and systemic inflammation in the H-ARS model.


Assuntos
Síndrome Aguda da Radiação , Sistema Hematopoético , Camundongos , Animais , Selectina E/uso terapêutico , Interleucina-2/uso terapêutico , Interleucina-6 , Camundongos Endogâmicos C57BL , Síndrome Aguda da Radiação/tratamento farmacológico , Sistema Hematopoético/metabolismo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Citocinas , Biomarcadores , Inflamação
15.
Cureus ; 14(8): e27817, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36106303

RESUMO

Background In this study, we aimed to assess the outcomes of transcutaneous retrobulbar injection of amphotericin B (TRAMB) in rhino-orbital-cerebral mucormycosis (ROCM) among patients recovering from coronavirus disease 2019 (COVID-19). Methodology This retrospective study was conducted at a tertiary care center in eastern India from May 29th to July 31st, 2021, and included post-COVID-19 patients admitted with stage 3 and 4a ROCM who underwent TRAMB. The details of the ophthalmic examination, laboratory investigations, and radiological examination were retrieved from patients records. Patients were given TRAMB (3.5 mg/mL) on alternate days till they underwent debulking surgery and resumed from the second postoperative day alternatively till the patients showed clinical stabilization or improvement. Results In total, 45 eyes of 41 patients were included in the study. The median number of injections given was six (minimum = 3; maximum = 10). Following was the distribution of number of injection needed in each eye: eight eyes (three injections), six eyes (four injections), seven eyes (five injections), three eyes (six injections), eight eyes (seven injections), 11 eyes (eight injections), and one eye had received nine and ten injections each. Overall, 21/32 (65.62%) eyes had improvement in proptosis whereas 9/32 (28.12%) had improvement in ptosis. Six patients had improvement in extraocular movement. In total, 25 eyes had no improvement whereas seven eyes had improvement in vision. Four eyes underwent exenteration. All nine patients with limited orbital disease had good improvement with fewer injections (median = 4). None of the patients undergoing TRAMB had an intracranial extension of disease. Moreover, 8.88% (4/45) of the eyes had post-TRAMB transient inflammation which resolved without any intervention. Finally, 3/41 of the patients died. Conclusions TRAMB can be considered as an useful therapeutic adjunct in managing ROCM. Further, it can halt the progression of the disease while awaiting definitive surgical intervention.

16.
Sci Rep ; 12(1): 11170, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778516

RESUMO

A laccase-producing hyper performer, Schizophyllum commune, a white-rot fungus, was evaluated for its ability to selectively degrade lignin of diverse crop residues in vitro. Relative analysis of crop residue treatment using laccase obtained from immobilized cells demonstrated degradation of 30-40% in finger millet straw and sorghum stover, 27-32% in paddy straw, 21% in wheat straw, and 26% in maize straw, while 20% lignin degradation was observed when purified and recombinant laccase was used. Further investigations into in vitro dry matter digestibility studies gave promising results recording digestibility of 54-59% in finger millet straw 33-36% in paddy straw and wheat straw, 16% in maize straw for laccase obtained from cell immobilization method, whereas 14% digestibility was observed when purified and recombinant laccase was used. Sorghum stover recorded digestibility of 13-15% across all straws treated with laccase. The results obtained elucidated the positive influence of laccase treatment on lignin degradation and in vitro dry matter digestibility. The present research gave encouraging figures confirming the production of laccase using the cell immobilization method to be an efficient production method commensurate with purified and recombinant laccase under conditions of submerged cultivation, proclaiming a cost-effective, environmentally safe green technology for effectual lignin depolymerization.


Assuntos
Basidiomycota , Schizophyllum , Animais , Basidiomycota/metabolismo , Lacase/metabolismo , Lignina/metabolismo , Ruminantes/metabolismo , Triticum/metabolismo , Zea mays/metabolismo
17.
Obstet Med ; 15(1): 56-58, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35444728

RESUMO

Cirrhosis is a multisystemic condition in which pregnancy is uncommon; however, the combination may lead to a higher incidence of spontaneous fetal loss and complications such as progressive jaundice, ascites and variceal bleeding. Here we present a 21-year-old woman who presented at 14 weeks' gestation with new jaundice and a two-month history of melena consistent with pre-existing cirrhosis of unclear aetiology. She delivered a healthy male infant at 34 weeks and five days of gestation vaginally with good haemostasis. In the literature, maternal mortality rates have been reported in up to 61% of these women, however, this risk is likely lower now with modern endoscopic therapies and improved access to blood products. There is limited information about labour and delivery in cirrhosis, although the best outcomes to date have been described in well-compensated women.

18.
Sci Rep ; 12(1): 3485, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241733

RESUMO

The threat of a nuclear attack has increased in recent years highlighting the benefit of developing additional therapies for the treatment of victims suffering from Acute Radiation Syndrome (ARS). In this work, we evaluated the impact of a PEGylated thrombopoietin mimetic peptide, JNJ-26366821, on the mortality and hematopoietic effects associated with ARS in mice exposed to lethal doses of total body irradiation (TBI). JNJ-26366821 was efficacious as a mitigator of mortality and thrombocytopenia associated with ARS in both CD2F1 and C57BL/6 mice exposed to TBI from a cobalt-60 gamma-ray source. Single administration of doses ranging from 0.3 to 1 mg/kg, given 4, 8, 12 or 24 h post-TBI (LD70 dose) increased survival by 30-90% as compared to saline control treatment. At the conclusion of the 30-day study, significant increases in bone marrow colony forming units and megakaryocytes were observed in animals administered JNJ-26366821 compared to those administered saline. In addition, enhanced recovery of FLT3-L levels was observed in JNJ-26366821-treated animals. Probit analysis of survival in the JNJ-26366821- and saline-treated cohorts revealed a dose reduction factor of 1.113 and significant increases in survival for up to 6 months following irradiation. These results support the potential use of JNJ-26366821 as a medical countermeasure for treatment of acute TBI exposure in case of a radiological/nuclear event when administered from 4 to 24 h post-TBI.


Assuntos
Síndrome Aguda da Radiação , Materiais Biomiméticos , Sistema Hematopoético , Trombopoetina , Síndrome Aguda da Radiação/tratamento farmacológico , Síndrome Aguda da Radiação/patologia , Animais , Materiais Biomiméticos/farmacologia , Sistema Hematopoético/patologia , Sistema Hematopoético/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/tratamento farmacológico , Lesões Experimentais por Radiação/patologia , Trombopoetina/farmacologia , Irradiação Corporal Total
19.
Front Pharmacol ; 12: 785165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912229

RESUMO

[This corrects the article DOI: 10.3389/fphar.2020.587970.].

20.
Radiat Res ; 196(2): 129-146, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33979439

RESUMO

Chartered by the U.S. Congress in 1961, the Armed Forces Radiobiology Research Institute (AFRRI) is a Joint Department of Defense (DoD) entity with the mission of carrying out the Medical Radiological Defense Research Program in support of our military forces around the globe. In the last 60 years, the investigators at AFRRI have conducted exploratory and developmental research with broad application to the field of radiation sciences. As the only DoD facility dedicated to radiation research, AFRRI's Medical Radiobiology Advisory Team provides deployable medical and radiobiological subject matter expertise, advising commanders in the response to a U.S. nuclear weapon incident and other nuclear or radiological material incidents. AFRRI received the DoD Joint Meritorious Unit Award on February 17, 2004, for its exceptionally meritorious achievements from September 11, 2001 to June 20, 2003, in response to acts of terrorism and nuclear/radiological threats at home and abroad. In August 2009, the American Nuclear Society designated the institute a nuclear historic landmark as the U.S.'s primary source of medical nuclear and radiological research, preparedness and training. Since then, research has continued, and core areas of study include prevention, assessment and treatment of radiological injuries that may occur from exposure to a wide range of doses (low to high). AFRRI collaborates with other government entities, academic institutions, civilian laboratories and other countries to research the biological effects of ionizing radiation. Notable early research contributions were the establishment of dose limits for major acute radiation syndromes in primates, applicable to human exposures, followed by the subsequent evolution of radiobiology concepts, particularly the importance of immune collapse and combined injury. In this century, the program has been essential in the development and validation of prophylactic and therapeutic drugs, such as Amifostine, Neupogen®, Neulasta®, Nplate® and Leukine®, all of which are used to prevent and treat radiation injuries. Moreover, AFRRI has helped develop rapid, high-precision, biodosimetry tools ranging from novel assays to software decision support. New drug candidates and biological dose assessment technologies are currently being developed. Such efforts are supported by unique and unmatched radiation sources and generators that allow for comprehensive analyses across the various types and qualities of radiation. These include but are not limited to both 60Co facilities, a TRIGA® reactor providing variable mixed neutron and γ-ray fields, a clinical linear accelerator, and a small animal radiation research platform with low-energy photons. There are five major research areas at AFRRI that encompass the prevention, assessment and treatment of injuries resulting from the effects of ionizing radiation: 1. biodosimetry; 2. low-level and low-dose-rate radiation; 3. internal contamination and metal toxicity; 4. radiation combined injury; and 5. radiation medical countermeasures. These research areas are bolstered by an educational component to broadcast and increase awareness of the medical effects of ionizing radiation, in the mass-casualty scenario after a nuclear detonation or radiological accidents. This work provides a description of the military medical operations as well as the radiation facilities and capabilities present at AFRRI, followed by a review and discussion of each of the research areas.


Assuntos
Academias e Institutos , Síndrome Aguda da Radiação/epidemiologia , Radiobiologia/história , Terrorismo , Síndrome Aguda da Radiação/patologia , Animais , Raios gama , História do Século XXI , Humanos , Militares , Nêutrons/efeitos adversos , Liberação Nociva de Radioativos
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