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1.
Pharm Res ; 40(12): 2935-2945, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37380906

RESUMEN

PURPOSE: Increased tablet anisotropy could lead to increased tablet capping propensity. Tooling design variables such as cup depth could serve as a key player for inducing tablet anisotropy. METHODS: A new capping index (CI) consisting of the ratio of compact anisotropic index (CAI) and material anisotropic index (MAI) is proposed to evaluate tablet capping propensity as a function of punch cup depth. CAI is the ratio of axial to radial breaking force. MAI is the ratio of axial to radial Young's modulus. The impact of various punch cup depths [flat face, flat face beveled edge, flat face radius edge, standard concave, shallow concave, compound concave, deep concave, and extra deep concave] on the capping propensity of model acetaminophen tablets was studied. Tablets were manufactured at 50, 100, 200, 250, and 300 MPa compression pressure at 20 RPM on different cup depth tools using Natoli NP-RD30 tablet press. A partial least squares model (PLS) was computed to model the impact of the cup depth and compression parameters on the CI. RESULTS: The PLS model exhibited a positive correlation of increased cup depth to the capping index. The finite elemental analysis confirmed that a high capping tendency with increased cup depth is a direct result of non-uniform stress distribution across powder bed. CONCLUSIONS: Certainly, a proposed new capping index with multivariate statistical analysis gives guidance in selecting tool design and compression parameters for robust tablets.


Asunto(s)
Acetaminofén , Fenómenos Mecánicos , Composición de Medicamentos , Presión , Comprimidos
2.
Pharm Dev Technol ; 27(7): 805-815, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36047995

RESUMEN

The novel modulus-based approach was developed to characterize the compression behavior of the materials and how it results into tablet mechanical strength (TMS) of the final tablet. The force-displacement profile for the model materials (Vivapur® 101, Starch 1500®, Emcompress®, and Tablettose® 100) was generated at different compression pressures (100, 150, and 200 MPa) and speeds (0.35, 0.55, and 0.75 m/s) using compaction emulator (Presster™). A generated continuous compression profile was evaluated with Heckel plot and the proposed material modulus method. The computed compression parameters were qualitatively and quantitatively correlated with TMS by principal component analysis and principal component regression, respectively. Compression modulus has negatively correlated, while decompression modulus is positively correlated to TMS. Proposed modulus descriptors are independent of particle density measurements required for the Heckel method and could overcome the limitations of the Heckel method to evaluate the decompression phase. Based on the outcome of the study, a two-dimensional compression and decompression modulus classification system (CDMCS) was proposed. The proposed CDMCS could be used to define critical material attributes in the early development stage or to understand reasons for tablet failure in the late development stage.


Asunto(s)
Química Farmacéutica , Almidón , Química Farmacéutica/métodos , Descompresión , Polvos , Comprimidos , Resistencia a la Tracción
3.
Curr Opin Nephrol Hypertens ; 30(1): 115-122, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33229911

RESUMEN

PURPOSE OF REVIEW: Diabetic kidney disease (DKD) is a leading cause of mortality and morbidity in diabetes. This review aims to discuss the major features of DKD, to identify the difficult barrier encountered in developing a therapeutic strategy and to provide a potentially superior novel approach to retard DKD. RECENT FINDINGS: Renal inflammation and fibrosis are prominent features of DKD. Transforming growth factor beta (TGFß) with its activity enhanced in DKD plays a key pathological profibrotic role in promoting renal fibrosis. However, TGFß is a difficult drug target because it has multiple important physiological functions, such as immunomodulation. These physiological functions of TGFß can be interrupted as a result of complete blockade of the TGFß pathway if TGFß is directly targeted, leading to catastrophic side-effects, such as fulminant inflammation. Cell division autoantigen 1 (CDA1) is recently identified as an enhancer of profibrotic TGFß signaling and inhibitor of anti-inflammatory SIRT1. Renal CDA1 expression is elevated in human DKD as well as in rodent models of DKD. Targeting CDA1, by either genetic approach or pharmacological approach in mice, leads to concurrent attenuation of renal fibrosis and inflammation without any deleterious effects observed. SUMMARY: Targeting CDA1, instead of directly targeting TGFß, represents a superior approach to retard DKD.


Asunto(s)
Autoantígenos , Nefropatías Diabéticas , Riñón , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Animales , Autoantígenos/genética , Autoantígenos/metabolismo , Citocinas/efectos adversos , Citocinas/fisiología , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/fisiopatología , Fibrosis/tratamiento farmacológico , Fibrosis/patología , Fibrosis/fisiopatología , Fibrosis/prevención & control , Humanos , Inflamación/tratamiento farmacológico , Inflamación/patología , Inflamación/fisiopatología , Inflamación/prevención & control , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Riñón/fisiopatología , Ratones , Sustancias Protectoras/uso terapéutico , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/fisiología
4.
EMBO Rep ; 19(5)2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29592859

RESUMEN

Cellular senescence is a physiological response by which an organism halts the proliferation of potentially harmful and damaged cells. However, the accumulation of senescent cells over time can become deleterious leading to diseases and physiological decline. Our data reveal a novel interplay between senescence and the stress response that affects both the progression of senescence and the behavior of senescent cells. We show that constitutive exposure to stress induces the formation of stress granules (SGs) in proliferative and presenescent cells, but not in fully senescent cells. Stress granule assembly alone is sufficient to decrease the number of senescent cells without affecting the expression of bona fide senescence markers. SG-mediated inhibition of senescence is associated with the recruitment of the plasminogen activator inhibitor-1 (PAI-1), a known promoter of senescence, to these entities. PAI-1 localization to SGs increases the translocation of cyclin D1 to the nucleus, promotes RB phosphorylation, and maintains a proliferative, non-senescent state. Together, our data indicate that SGs may be targets of intervention to modulate senescence in order to impair or prevent its deleterious effects.


Asunto(s)
Senescencia Celular , Gránulos Citoplasmáticos/metabolismo , Inhibidor 1 de Activador Plasminogénico/metabolismo , Estrés Fisiológico , Línea Celular , Núcleo Celular/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Humanos , Fosforilación , Inhibidor 1 de Activador Plasminogénico/genética
5.
Int J Mol Sci ; 21(6)2020 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-32210089

RESUMEN

The major clinical associations with the progression of diabetic kidney disease (DKD) are glycemic control and systemic hypertension. Recent studies have continued to emphasize vasoactive hormone pathways including aldosterone and endothelin which suggest a key role for vasoconstrictor pathways in promoting renal damage in diabetes. The role of glucose per se remains difficult to define in DKD but appears to involve key intermediates including reactive oxygen species (ROS) and dicarbonyls such as methylglyoxal which activate intracellular pathways to promote fibrosis and inflammation in the kidney. Recent studies have identified a novel molecular interaction between hemodynamic and metabolic pathways which could lead to new treatments for DKD. This should lead to a further improvement in the outlook of DKD building on positive results from RAAS blockade and more recently newer classes of glucose-lowering agents such as SGLT2 inhibitors and GLP1 receptor agonists.


Asunto(s)
Presión Sanguínea , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/fisiopatología , Glucosa/metabolismo , Redes y Vías Metabólicas , Animales , Biomarcadores , Glucemia , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/patología , Progresión de la Enfermedad , Hemodinámica , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Sistema Renina-Angiotensina/efectos de los fármacos , Transducción de Señal
6.
BMC Genomics ; 20(1): 609, 2019 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-31340764

RESUMEN

BACKGROUND: Reporter methods to quantitatively measure the efficiency and specificity of genome editing tools are important for the development of novel editing techniques and successful applications of available ones. However, the existing methods have major limitations in sensitivity, accuracy, and/or readiness for in vivo applications. Here, we aim to develop a straight-forward method by using nucleotide insertion/deletion resulted from genome editing. In this system, a target sequence with frame-shifting length is inserted after the start codon of a cerulean fluorescence protein (CFP) to inactivate its fluorescence. As such, only a new insertion/deletion event in the target sequence will reactivate the fluorescence. This reporter is therefore termed as "Insertion/deletion-activated frame-shift fluorescence protein". To increase its traceability, an internal ribosome entry site and a red fluorescence protein mCherryFP are placed downstream of the reporter. The percentage of CFP-positive cells can be quantified by fluorescence measuring devices such as flow cytometer as the readout for genome editing frequency. RESULTS: To test the background noise level, sensitivity, and quantitative capacity of this new reporter, we applied this approach to examine the efficiency of genome editing of CRISPR/Cas9 on two different targeting sequences and in three different cell lines, in the presence or absence of guide-RNAs with or without efficiency-compromising mutations. We found that the insertion/deletion-activated frame-shift fluorescence protein has very low background signal, can detect low-efficiency genome editing events driven by mutated guideRNAs, and can quantitatively distinguish genome editing by normal or mutated guideRNA. To further test whether the positive editing event detected by this reporter indeed correspond to genuine insertion/deletion on the genome, we enriched the CFP-positive cells to examine their fluorescence under confocal microscope and to analyze the DNA sequence of the reporter in the genome by Sanger sequencing. We found that the positive events captured by this reporter indeed correlates with genuine DNA insertion/deletion in the expected genome location. CONCLUSION: The insertion/deletion-activated frame-shift fluorescence protein reporter has very low background, high sensitivity, and is quantitative in nature. It will be able to facilitate the development of new genome editing tools as well as the application of existing tools.


Asunto(s)
Mutación del Sistema de Lectura , Edición Génica , Mutación INDEL , Proteínas Luminiscentes/genética , Animales , Células CHO , Sistemas CRISPR-Cas , Codón Iniciador , Cricetulus , Fibroblastos , Fluorescencia , Genes Reporteros , Células HEK293 , Humanos , Sitios Internos de Entrada al Ribosoma , Ratones , ARN Guía de Kinetoplastida
7.
J Prosthet Dent ; 121(3): 404-410, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30396711

RESUMEN

STATEMENT OF PROBLEM: The design of porous tantalum trabecular metal-enhanced titanium (TM) dental implants promises improved osseointegration, especially when grafting materials such as demineralized bone matrix are used; however, studies are lacking. PURPOSE: The purpose of this retrospective study was to compare TM implants with conventional titanium alloy (Ti) implants with and without demineralized bone matrix in terms of peri-implant bone remodeling in the first year after implant loading. MATERIAL AND METHODS: A chart review was used for all patients receiving Tapered Screw-Vent Ti and TM implants. Implants were placed and restored by a single provider between 2011 and 2015. Peri-implant bone remodeling was compared by using a paired t test (α=.05). RESULTS: A total of 82 patients received 205 implants, 44 TM and 161 Ti implants (control). No implants failed in the TM group (survival rate of 100%), and 3 implants in total, 1 immediate, failed in the Ti groups (survival rate of 98.1%). TM implants exhibited a 0.28-mm bone gain on average, whereas the control group demonstrated 0.20 mm of marginal bone loss after the first year of implant loading. Multivariate logistic regression analysis demonstrated that the odds of having bone loss was 64% less (odds ratio: 0.36; 95% confidence interval: 0.14-0.94) in the TM group than in the Ti group after controlling for bone grafting, implant location, immediate placement, bone type, and pretreatment bone level. CONCLUSIONS: TM implants exhibited less peri-implant bone loss than the control Ti implants.


Asunto(s)
Pérdida de Hueso Alveolar , Implantes Dentales , Implantación Dental Endoósea , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado , Humanos , Porosidad , Estudios Retrospectivos , Tantalio , Titanio , Resultado del Tratamiento
8.
AIDS Care ; 28(5): 561-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26766017

RESUMEN

Outcomes following healthcare transition (HCT) from pediatric to adult HIV care are not well described. We sought to describe clinical outcomes following HCT within our institution among young adults with behavioral-acquired (N = 31) and perinatally-acquired (N = 19) HIV. We conducted a retrospective cohort study among HIV-infected adults who attempted transition from pediatric to adult HIV care within our institution. The primary end point was retention in care, defined as the completion of at least two visits over 12 months following linkage to adult care. Additional end points include time to linkage to adult care, and changes in CD4 + T cell count and HIV RNA across time. Outcomes were compared between perinatal and behavioral HIV cohorts. Binary data were analyzed using the Fisher exact test and continuous data were analyzed using the Mann-Whitney test. Forty-three (86%) of 50 patients were successfully linked to adult care. The median time to linkage was 98 days. Fifty percent of patients achieved full retention in care at 12 months post-linkage. Though those with behavioral-acquired HIV attempted transfer at an older age, the groups did not differ in rates of linkage and retention in adult care. CD4 + T cell counts and rates of viral suppression did not differ between pre- and post-HCT periods. Despite high rates of successful linkage to adult care in our study population, rates of retention in adult HIV care following HCT were low. These results imply that challenges remain in the adult HIV care setting toward improving the HCT process.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Continuidad de la Atención al Paciente/organización & administración , Infecciones por VIH/tratamiento farmacológico , Aceptación de la Atención de Salud , Planificación de Atención al Paciente , Transición a la Atención de Adultos , Adolescente , Adulto , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
10.
Traffic ; 13(1): 120-30, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22008230

RESUMEN

The role of actin, class I myosins and dynamin in endocytic uptake processes is well characterized, but their role during endo-phagosomal membrane trafficking and maturation is less clear. In Dictyostelium, knockout of myosin IB (myoB) leads to a defect in membrane protein recycling from endosomes back to the plasma membrane. Here, we show that actin plays a central role in the morphology and function of the endocytic pathway. Indeed, latrunculin B (LatB) induces endosome tubulation, a phenotype also observed in dynamin A (dymA)-null cells. Knockout of dymA impairs phagosome acidification, whereas knockout of myoB delays reneutralization, a phenotype mimicked by a low dose of LatB. As a read out for actin-dependent processes during maturation, we monitored the capacity of purified phagosomes to bind F-actin in vitro, and correlated this with the presence of actin-binding and membrane-trafficking proteins. Phagosomes isolated from myoB-null cells showed an increased binding to F-actin, especially late phagosomes. In contrast, early phagosomes from dymA-null cells showed reduced binding to F-actin while late phagosomes were unaffected. We provide evidence that Abp1 is the main F-actin-binding protein in this assay and is central for the interplay between DymA and MyoB during phagosome maturation.


Asunto(s)
Actinas/metabolismo , Dinaminas/metabolismo , Endosomas/metabolismo , Proteínas de Microfilamentos/metabolismo , Miosina Tipo I/metabolismo , Fagosomas/metabolismo , Proteínas Protozoarias/metabolismo , Western Blotting , Dictyostelium/metabolismo , Dictyostelium/ultraestructura , Dinaminas/genética , Endosomas/ultraestructura , Técnicas de Inactivación de Genes , Modelos Biológicos , Miosina Tipo I/genética , Fagocitosis , Fagosomas/ultraestructura , Transporte de Proteínas , Proteínas Protozoarias/genética
12.
J Clin Microbiol ; 57(8)2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31350374
13.
J Cell Sci ; 124(Pt 4): 578-88, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21245195

RESUMEN

Remodelling of the actin cytoskeleton plays a key role in particle internalisation and the phagosome maturation processes. Actin-binding proteins (ABPs) are the main players in actin remodelling but the precise role of these proteins in phagocytosis needs to be clarified. Annexins, a group of ABPs, are known to be present on phagosomes. Here, we identified annexin A1 as a factor that binds to isolated latex bead phagosomes (LBPs) in the presence of Ca(2+) and facilitates the F-actin-LBP interaction in vitro. In macrophages the association of endogenous annexin A1 with LBP membranes was strongly correlated with the spatial and temporal accumulation of F-actin at the LBP. Annexin A1 was found on phagocytic cups and around early phagosomes, where the F-actin was prominently concentrated. After uptake was completed, annexin A1, along with F-actin, dissociated from the nascent LBP surface. At later stages of phagocytosis annexin A1 transiently concentrated only around those LBPs that showed transient F-actin accumulation ('actin flashing'). Downregulation of annexin A1 expression resulted in impaired phagocytosis and actin flashing. These data identify annexin A1 as an important component of phagocytosis that appears to link actin accumulation to different steps of phagosome formation.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Anexina A1/metabolismo , Fagocitosis , Fagosomas/metabolismo , Citoesqueleto de Actina/genética , Actinas/metabolismo , Animales , Anexina A1/genética , Línea Celular , Ratones , Unión Proteica
14.
Int J Pharm ; 635: 122710, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36773731

RESUMEN

Punch sticking has been a leading drawback that has challenged successful tablet manufacturing since its initial conception. Due to the capricious nature of the complication, this can arise during any phase of the development process. Even now, identifying such a problem is a prerequisite during the initial stage of development. The present study evaluated the role of Aerosil®200, talc, and Syloid®244 as glidants in varying amounts ranging from 0.0 percent to 2.0 percent w/w on tablets sticking relatively to five different metal surfaces, with ketoprofen as the model drug. Powder rheology is a predictable technique used to calculate the sticking index. The sticking index of each formulation in comparison to each metal coupon was identified by calculating the kinematic angle of internal friction and the angle of wall friction using the shear cell test and wall friction test, respectively. Interestingly, glidants were found to reduce the sticking propensity of the powder blend in a concentration-dependent manner. In addition, the compression study validated the expected sticking tendency ranking order. According to the research data, the sticking index could effectively be utilized to envisage the possibility of tablet sticking, i.e., by selecting the formulation's excipient and their percentages or selecting appropriate punched metal surfaces in the tableting process.


Asunto(s)
Cetoprofeno , Polvos , Comprimidos , Presión , Excipientes , Composición de Medicamentos/métodos
15.
Res Social Adm Pharm ; 19(1): 167-179, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36031527

RESUMEN

BACKGROUND: Increasing demographic healthcare challenges, such as increased life expectancy coupled with increased use of medicines for complex morbidities, point to the need for globally applicable transformative policies in health workforce development. The International Pharmaceutical Federation (FIP) has established a set of 21 Global Development Goals (FIP DGs) to strengthen pharmacy workforce and benchmark professional developmental needs. OBJECTIVE: This study aimed to identify policy directions and factors affecting pharmacy workforce development across the Commonwealth, and to examine country progress made towards implementing workforce oriented FIP DGs. METHODS: The study involved a literature review and a global survey of commonwealth countries professional leadership bodies. The literature database search included PubMed/Medline, CINAHL, Scopus and PsychINFO databases as well as the websites of the respective national pharmacy organisations of Commonwealth countries. A global survey was also conducted to assess country-level alignment with the workforce component of FIP DGs. RESULTS: Thirty-one articles representing 21 Commonwealth countries were included in the literature overview. The development needs identified were workforce shortages and inequitable distribution across practice areas and geographical regions, low workforce supply capacity, workforce feminisation, lack of professional recognition, limited training opportunities, low job satisfaction, high workload and attrition. The survey showed disparities in country-level progress and alignment with the FIP DGs. High-income countries in the survey sample reported alignment with most of the FIP DGs, while the low-income countries reported alignment with fewer DGs. More than two-thirds of the countries showed alignment with the FIP DGs related to academic capacity, early career training, quality assurance and advancing integrated services. About half reported alignment with the FIP DGs related to competency and leadership development, respectively, while only a third aligned with the equity and equality DG. CONCLUSION: This study identified realistic pharmacy workforce developmental needs across a range of Commonwealth countries. Addressing these needs through appropriate policy interventions will be essential for increasing the pharmacy workforce capacity and assuring the delivery of high-quality pharmaceutical care and medicines expertise in these countries.


Asunto(s)
Fuerza Laboral en Salud , Evaluación de Necesidades , Farmacéuticos , Humanos , Servicios Farmacéuticos
16.
Ann Glob Health ; 89(1): 52, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37575336

RESUMEN

The global health exchange program between the University Teaching Hospitals (UTH) of Lusaka, Zambia and the University of Maryland, Baltimore (UMB) has been operating since 2015. As trainees and facilitators of this exchange program, we describe our experiences working in Lusaka and Baltimore, and strengths and challenges of the partnership. Since 2015, we have facilitated rotations for 71 UMB trainees, who spent four weeks on the Infectious Disease (ID) team at UTH. Since 2019 with funding from UMB, nine UTH ID trainee physicians spent up to six weeks each rotating on various ID consult services at University of Maryland Medical Center (UMMC). Challenges in global health rotations can include inadequate preparation or inappropriate expectations among high-income country trainees, low-value experiences for low- and middle-income country trainees, lack of appropriate mentorship at sites, and power imbalances in research collaborations. We try to mitigate these issues by ensuring pre-departure and on-site orientation for UMB trainees, cross-cultural mentored experiences for all trainees, and intentional sharing of authorship and credit on scientific collaborations. We present a description of our medical education collaboration as a successful model for building equitable and reciprocal collaborations between low- and middle-income countries and high-income countries, and offer suggestions for future program initiatives to enhance global health education equity among participants and organizations.


Asunto(s)
Salud Global , Educación en Salud , Humanos , Universidades , Zambia , Hospitales de Enseñanza
17.
Curr Infect Dis Rep ; 14(1): 91-101, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22143960

RESUMEN

Africa carries a disproportionate burden of the global HIV endemic, accounting for two thirds of the global 33.3 million people living with HIV. While tremendous advances have been made in addressing the HIV epidemic in Africa, considerable challenges remain. Testing for HIV increased by 86% from 2007 to 2009 but more than 75% of people 15-49 years remain unaware of their HIV status. CD4 count at diagnosis tends to be low and linkage to care and treatment is suboptimal. The scale-up of antiretroviral therapy is ongoing but is hampered by the lack of diagnostic capability to monitor response to therapy and a substantial healthcare workforce shortage. Prevention strategies such as male circumcision, pre-exposure prophylaxis, and antiretroviral therapy for prevention have generated great excitement but cost and healthcare infrastructure deficiencies may limit their widespread applicability. Operational research to validate and inform treatment decisions, health care policies, and prevention strategies is sorely needed.

18.
Int J Pharm ; 627: 122205, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36122616

RESUMEN

A parameterization of compaction simulator generated dynamic compression profile with a few grams of powder provides important information about the material deformation and compact elasticity. The Heckel equation is by far the most popular choice among pharmaceutical scientists for such parametrization. A general approach of Heckel analysis uses pycnometric powder density (ρP0) for relative density calculation. However, as 'in-die' tablet bulk density at applied compression pressure (ρBP) becomes greater than or equal to the measured ρP0, the general approach typically poses a negative porosity challenge at high compression pressure regions. It is only theoretically possible to have a tablet with zero or negative porosity. Negative porosity may be detected during 'in-die' compression analysis, but it will not exist after ejection of the tablet in practical aspect. Thus, the present work proposes a new approach to using pycnometric tablet density (ρPP) in the relative density calculations of Heckel analysis. This ρPP may be a better representation of actual tablet particle volume, as it is composed of non-accessible intra-particulate pores, which are broken under applied compression pressure. A new approach showed its immunity for Heckel high-pressure negative porosity. It enables the utilization of the compression and decompression phases of dynamic compression profiles to evaluate macroscopic compaction performance. The proposed approach was validated with a reported modified Heckel approach. The Heckel parameters computed with both methodologies for microcrystalline cellulose and lactose were not statistically different. However, a modified Heckel approach was unable to compute Heckel parameters of poorly compacting starch unlike the new approach. A modified Heckel approach became invalid during starch compaction at low compression pressures (below 400 MPa), where starch was forming weaker but still intact tablets. Certainly, a complete Heckel profiling with a new approach could save time and costs in an early development stage for designing and screening scientifically based lead prototype formulations.


Asunto(s)
Lactosa , Tecnología Farmacéutica , Porosidad , Polvos , Tecnología Farmacéutica/métodos , Comprimidos , Almidón
19.
IDCases ; 28: e01465, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35284229

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical syndrome of inappropriate immune activation which can present at any age and is commonly associated with other conditions of either excessive or impaired immune response, such as malignancy, infection, autoimmunity or immunodeficiency. In cases associated with human immunodeficiency virus (HIV) infection, an additional trigger such as acute infection or malignancy is frequently identified. We report a case of HLH presenting in a patient with uncontrolled HIV and reactivated hepatitis B infection, which to our knowledge has only been reported once before. Given challenges with diagnosis and its life-threatening course, HLH is an important consideration especially in critically ill patients with underlying HIV and nonspecific presentations such as fevers, cytopenias and encephalopathy.

20.
Dev Cell ; 57(5): 654-669.e9, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35247316

RESUMEN

The response to oxygen availability is a fundamental process concerning metabolism and survival/death in all mitochondria-containing eukaryotes. However, the known oxygen-sensing mechanism in mammalian cells depends on pVHL, which is only found among metazoans but not in other species. Here, we present an alternative oxygen-sensing pathway regulated by ATE1, an enzyme ubiquitously conserved in eukaryotes that influences protein degradation by posttranslational arginylation. We report that ATE1 centrally controls the hypoxic response and glycolysis in mammalian cells by preferentially arginylating HIF1α that is hydroxylated by PHD in the presence of oxygen. Furthermore, the degradation of arginylated HIF1α is independent of pVHL E3 ubiquitin ligase but dependent on the UBR family proteins. Bioinformatic analysis of human tumor data reveals that the ATE1/UBR and pVHL pathways jointly regulate oxygen sensing in a transcription-independent manner with different tissue specificities. Phylogenetic analysis suggests that eukaryotic ATE1 likely evolved during mitochondrial domestication, much earlier than pVHL.


Asunto(s)
Aminoaciltransferasas , Oxígeno , Aminoaciltransferasas/genética , Aminoaciltransferasas/metabolismo , Animales , Humanos , Mamíferos/metabolismo , Filogenia , Proteolisis
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