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1.
Int J Pharm ; 654: 123977, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38458403

RESUMEN

Bottom-up production of active pharmaceutical ingredient (API) crystal suspensions offers advantages in surface property control and operational ease over top-down methods. However, downstream separation and concentration pose challenges. This proof-of-concept study explores membrane diafiltration as a comprehensive solution for downstream processing of API crystal suspensions produced via anti-solvent crystallization. It involves switching the residual solvent (N-methyl-2-pyrrolidone, NMP) with water, adjusting the excipient (d-α-Tocopherol polyethylene glycol 1000 succinate, TPGS) quantity, and enhancing API loading (solid concentration) in itraconazole crystal suspensions. NMP concentration was decreased from 9 wt% to below 0.05 wt% (in compliance with European Medicine Agency guidelines), while the TPGS concentration was decreased from 0.475 wt% to 0.07 wt%. This reduced the TPGS-to-itraconazole ratio from 1:2 to less than 1:50 and raised the itraconazole loading from 1 wt% to 35.6 wt%. Importantly, these changes did not adversely affect the itraconazole crystal stability in suspension. This study presents membrane diafiltration as a one-step solution to address downstream challenges in bottom-up API crystal suspension production. These findings contribute to optimizing pharmaceutical manufacturing processes and hold promise for advancing the development of long-acting API crystal suspensions via bottom-up production techniques at a commercial scale.


Asunto(s)
Itraconazol , Agua , Itraconazol/química , Solventes/química , Propiedades de Superficie , Tecnología , Suspensiones , Solubilidad , Tamaño de la Partícula
2.
Int J Pharm ; 652: 123846, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38272195

RESUMEN

Long-acting crystal suspensions of active pharmaceutical ingredients (API) mostly comprised of an API, a suspension media (water) and excipients and provide sustained API release over time. Excipients are crucial for controlling particle size and to achieve the stability of the API crystals in suspension. A bottom-up process was designed to produce long-acting crystal suspensions whilst investigating the excipient requirements during the production process and the subsequent storage. PVP K30 emerged as the most effective excipient for generating stable naproxen crystals with the desired size of 1 to 15 µm, using ethanol as solvent and water as anti-solvent. Calculations, performed based on the crystal properties and assuming complete PVP K30 adsorption on the crystal surface, revealed lower PVP K30 requirements during storage compared to initial crystal generation. Consequently, a membrane-based diafiltration process was used to determine and fine-tune PVP K30 concentration in the suspension post-crystallization. A seven-stage diafiltration process removed 98 % of the PVP K30 present in the suspension thereby reducing the PVP-to-naproxen ratio from 1:2 to 1:39 without impacting the stability of naproxen crystals in suspension. This work provides insights into the excipient requirements at various production stages and introduce the membrane-based diafiltration for precise excipient control after crystallization.


Asunto(s)
Química Farmacéutica , Excipientes , Excipientes/química , Naproxeno/química , Povidona/química , Tecnología , Agua/química , Suspensiones , Solubilidad
3.
Membranes (Basel) ; 13(3)2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36984651

RESUMEN

Bottom-up approaches to producing aqueous crystal suspensions of active pharmaceutical ingredients (APIs), such as anti-solvent crystallisation, are gaining interest as they offer better control over surface properties compared to top-down approaches. However, one of the major challenges that needs to be addressed is the removal of organic solvents after the crystallisation step due to strict limitations regarding human exposure. Within this work, we investigated a process concept for the removal of solvent (i.e., ethanol) from the API crystal suspension using membrane-based diafiltration. A four-stage diafiltration process successfully reduced the ethanol concentration in the API (here, naproxen) crystal suspension below 0.5 wt% (the residual solvent limit as per ICH guidelines) with a water consumption of 1.5 g of added water per g of feed. The solvent exchange process had no negative influence on the stability of the crystals in suspension, as their size and polymorphic form remained unchanged. This work is a step towards the bottom-up production of API crystal suspension by applying solvent/anti-solvent crystallisation. It provides the proof of concept for establishing a process of organic solvent removal and offers an experimental framework to serve as the foundation for the design of experiments implementing a solvent exchange in API production processes.

4.
Trials ; 23(1): 932, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36348476

RESUMEN

BACKGROUND: COVID-19 poses a global health challenge with more than 325 million cumulative cases and above 5 million cumulative deaths reported till January 17, 2022, by the World Health Organization. Several potential treatments to treat COVID-19 are under clinical trials including antivirals, steroids, immunomodulators, non-specific IVIG, monoclonal antibodies, and passive immunization through convalescent plasma. The need to produce anti-COVID-19 IVIG therapy must be continued, alongside the current treatment modalities, considering the virus is still mutating into variants of concern. In this context, as the present study will exploit pooled diversified convalescent plasma collected from recovered COVID-19 patients, the proposed hyperimmune Anti-COVID-19 intravenous immunoglobulin (C-IVIG) therapy would be able to counter new infectious COVID-19 variants by neutralizing the virus particles. After the successful outcome of the phase I/II clinical trial of C-IVIG, the current study aims to further evaluate the safety and efficacy of single low dose C-IVIG in severe COVID-19 patients for its phase II/III clinical trial. METHODS: This is a phase II/III, adaptive, multi-center, single-blinded, randomized controlled superiority trial of SARS-CoV-2 specific polyclonal IVIG (C-IVIG). Patients fulfilling the eligibility criteria will be block-randomized using a sealed envelope system to receive either 0.15 g/Kg C-IVIG with standard of care (SOC) or standard of care alone in 2:1 ratio. The patients will be followed-up for 28 days to assess the primary and secondary outcomes. DISCUSSION: This is a phase II/III clinical trial evaluating safety and efficacy of hyperimmune anti-COVID-19 intravenous immunoglobulin (C-IVIG) in severe COVID-19 patients. This study will provide clinical evidence to use C-IVIG as one of the first-line therapeutic options for severe COVID-19 patients. TRIAL REGISTRATION: Registered at clinicaltrial.gov with NCT number NCT04891172 on May 18, 2021.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Infecciones por Coronavirus , Neumonía Viral , Humanos , SARS-CoV-2 , Betacoronavirus , Neumonía Viral/tratamiento farmacológico , Inmunoglobulinas Intravenosas/efectos adversos , Infecciones por Coronavirus/tratamiento farmacológico , Pandemias , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Sueroterapia para COVID-19
5.
Food Sci Nutr ; 9(11): 6421-6428, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34760271

RESUMEN

Fermented foods are an essential source of nutrition for the communities living in developing areas of the world. Additionally, traditional fermented products are a rich source of various bioactive components. Experimental research regarding the functional exploration of these products is a way forward for better human health. Among fermented foods, Koumiss is rich in vitamins especially vitamin C and minerals, i.e., phosphorus and calcium. In addition, it is also rich in vitamins A, E, B2, B12, and pantothenic acid. High concentrations of lactose in milk favor bacterial fermentation, as the original cultures decompose it into lactic acid. Koumiss contains essential fatty acids such as linoleic and linolenic acid. Koumiss offers many health benefits including boosting the immune system and maintains blood pressure, good effect on the kidneys, endocrine glands, gut system, liver, and nervous and vascular system. The rich microflora from the fermented product has a pivotal role in maintaining gut health and treating various digestive diseases. The core focus of the current review paper is to highlight the nutritional and therapeutic potential, i.e., anticarcinogenic, hypocholesterolemia effect, antioxidative properties, antibacterial properties, antibacterial spectrum, intestinal enlargement, and ß-galactosidase activity, of Koumiss as a traditional fermented product. Moreover, history and production technology of the Koumiss are also the main part of this review paper.

6.
Pulm Circ ; 11(4): 20458940211046838, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594546

RESUMEN

We aim to study the impact of pulmonary hypertension on acutely exacerbated chronic obstructive pulmonary disease (AECOPD). We used the 2016 and 2017 National Readmission Database with an inclusion criterion of AECOPD as a primary and pulmonary hypertension as a secondary diagnosis using ICD 10-CM codes. Exclusion criteria were age under 18 years, non-elective admission, and discharge in December. The primary outcome was in-hospital mortality during the index admission. Secondary outcomes were 30-day readmission rate, resource utilization, and instrument utilization including intubation, prolonged invasive mechanical ventilation >96 h (PIMV), tracheostomy, chest tube placement, and bronchoscopy during the index admission. A total of 627,848 patients with AECOPD were included in the study, and 68,429 (10.90%) patients had a diagnosis of pulmonary hypertension. Pulmonary hypertension was more common among females (61.14%) with a mean age of 71 ± 11.66, Medicare recipients (79.5%), higher Charlson comorbidity index, and treatment in an urban teaching hospital. Pulmonary hypertension was associated with greater mortality (adjusted odds ratio (aOR) 1.89, p < 0.001), higher 30-day readmission (aOR 1.24, p < 0.001), higher cost (adjusted mean difference (aMD) $2785, p < 0.01), length of stay (aMD 1.09, p < 0.001), and higher instrument utilization including intubation (aOR 199, p < 0.001), PIMV (aOR 2.12, p < 0.001), tracheostomy (aOR 2.1, p < 0.001), bronchoscopy (aOR 1.46, p = 0.007), and chest tube placement (aOR 1.39 p < 0.004). We found that pulmonary hypertension is related to higher in-hospital mortality, length of stay, increased instrument utilization, readmission, and costs. Our study aims to shed light on the impact of pulmonary hypertension on AECOPD in hopes to improve future management.

7.
EClinicalMedicine ; 36: 100926, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34109306

RESUMEN

BACKGROUND: Hyperimmune anti-COVID-19 Intravenous Immunoglobulin (C-IVIG) is an unexplored therapy amidst the rapidly evolving spectrum of medical therapies for COVID-19 and is expected to counter the three most life-threatening consequences of COVID-19 including lung injury by the virus, cytokine storm and sepsis. METHODS: A single center, phase I/II, randomized controlled, single-blinded trial was conducted at Dow University of Health Sciences, Karachi, Pakistan. Participants were COVID-19 infected individuals, classified as either severely or critically ill with Acute Respiratory Distress Syndrome (ARDS). Participants were randomized through parallel-group design with sequential assignment in a 4:1 allocation to either intervention group with four C-IVIG dosage arms (0.15, 0.20, 0.25, 0.30 g/kg), or control group receiving standard of care only (n = 10). Primary outcomes were 28-day mortality, patient's clinical status on ordinal scale and Horowitz index (HI), and were analysed in all randomized participants that completed the follow-up period (intention-to-treat population). The trial was registered at clinicaltrials.gov (NCT04521309). FINDINGS: Fifty participants were enrolled in the study from June 19, 2020 to February 3, 2021 with a mean age of 56.54±13.2 years of which 22 patients (44%) had severe and 28 patients (56%) had critical COVID-19. Mortality occurred in ten of 40 participants (25%) in intervention group compared to six of ten (60%) in control group, with relative risk reduction in intervention arm I (RR, 0.333; 95% CI, 0.087-1.272), arm II (RR, 0.5; 95% CI, 0.171-1.463), arm III (RR, 0.167; 95% CI, 0.024-1.145), and arm IV (RR, 0.667; 95% CI, 0.268-1.660). In intervention group, median HI significantly improved to 359 mmHg [interquartile range (IQR) 127-400, P = 0.009)] by outcome day, while the clinical status of intervention group also improved as compared to control group, with around 15 patients (37.5%) being discharged by 7th day with complete recovery. Additionally, resolution of chest X-rays and restoration of biomarkers to normal levels were also seen in intervention groups. No drug-related adverse events were reported during the study. INTERPRETATION: Administration of C-IVIG in severe and critical COVID-19 patients was safe, increased the chance of survival and reduced the risk of disease progression. FUNDING: Higher Education Commission (HEC), Pakistan (Ref no. 20-RRG-134/RGM/R&D/HEC/2020).

9.
Immunotherapy ; 13(5): 397-407, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33557591

RESUMEN

Background: This study assesses the feasibility of producing hyperimmune anti-COVID-19 intravenously administrable immunoglobulin (C-IVIG) from pooled convalescent plasma (PCP) to provide a safe and effective passive immunization treatment option for COVID-19. Materials & methods: PCP was fractionated by modified caprylic acid precipitation followed by ultrafiltration/diafiltration to produce hyperimmune C-IVIG. Results: In C-IVIG, the mean SARS-CoV-2 antibody level was found to be threefold (104 ± 30 cut-off index) that of the PCP (36 ± 8.5 cut-off index) and mean protein concentration was found to be 46 ± 3.7 g/l, comprised of 89.5% immunoglobulins. Conclusion: The current method of producing C-IVIG is feasible as it uses locally available PCP and simpler technology and yields a high titer of SARS-CoV-2 antibody. The safety and efficacy of C-IVIG will be evaluated in a registered clinical trial (NCT04521309).


Asunto(s)
Anticuerpos Antivirales/aislamiento & purificación , COVID-19/sangre , Inmunoglobulinas Intravenosas/aislamiento & purificación , SARS-CoV-2/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/uso terapéutico , COVID-19/terapia , Caprilatos/química , Fraccionamiento Químico , Humanos , Inmunización Pasiva , Inmunoglobulinas Intravenosas/inmunología , Inmunoglobulinas Intravenosas/uso terapéutico , Sueroterapia para COVID-19
10.
Heart Lung ; 50(2): 202-205, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33302147

RESUMEN

COVID-19 is a relatively new and rapidly emerging disease. Given current knowledge of the disease process, it is of the utmost importance to gain further insight into its different clinical manifestations. In this report we describe three cases involving Hispanic males with COVID-19 all of whom developed pneumomediastinum during their hospital course. We want to emphasize the importance of this adverse event despite their non-smoking history and the exclusion of positive pressure ventilation. Frequent chest radiographs help with early recognition of this disease process. Early detection of pneumomediastinum is important as this could lead to worse morbidity if left unrecognized despite its usually benign nature.


Asunto(s)
COVID-19 , Enfisema Mediastínico , Enfisema Subcutáneo , Humanos , Ventilación con Presión Positiva Intermitente , Masculino , Enfisema Mediastínico/diagnóstico por imagen , Enfisema Mediastínico/etiología , SARS-CoV-2
11.
Respir Med Case Rep ; 31: 101303, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33294361

RESUMEN

Coronavirus disease 2019 (COVID-19) has spread to more than 70 countries around the world since its discovery in 2019. More than 2.5 million cases and more than 130,000 deaths have been reported in the United States alone. The common radiological presentation in this disease is noted to be the presence of ground glass opacities and/or consolidations. We report a case of 40-year-old male admitted for COVID-19 and rapidly deteriorated into severe acute respiratory distress syndrome requiring intubation and mechanical ventilation with no prior history of smoking or lung disease. The patient had normal imaging 3 days prior to admission to the hospital and rapidly developed a large pneumatocele with pneumothorax requiring chest tube placement that later on resolved. This is a unique radiologic finding in COVID-19 and likely related to severe inflammation secondary to SARS-CoV-2 infection.

12.
Trials ; 21(1): 905, 2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33138867

RESUMEN

OBJECTIVES: The aim of this trial is to investigate the safety and clinical efficacy of passive immunization therapy through Hyperimmune anti-COVID-19 Intravenous Immunoglobulin (C-IVIG: 5% liquid formulation), on severe and critically ill patients with COVID-19. TRIAL DESIGN: This is a phase I/II single centre, randomised controlled, single-blinded, superiority trial, through parallel-group design with sequential assignment. Participants will be randomised either to receive both C-IVIG and standard care or only standard care (4:1). PARTICIPANTS: The study is mono-centric with the participants including COVID19 infected individuals (positive SARS-CoV-2 PCR on nasopharyngeal and/or oropharyngeal swabs) admitted in institute affiliated with Dow University Hospital, Dow University of Health Sciences, Karachi, Pakistan. Consenting patients above 18 years that are classified by the treating physician as severely ill i.e. showing symptoms of COVID-19 pneumonia; dyspnea, respiratory rate ≥30/min, blood oxygen saturation ≤93%, PaO2/FiO2 <300, and lung infiltrates >50% on CXR; or critically ill i.e. respiratory failure, septic shock, and multiple organ dysfunction or failure. Patients with reported IgA deficiency, autoimmune disorder, thromboembolic disorder, and allergic reaction to immunoglobulin treatment were excluded from study. Similarly, pregnant females, patients requiring two or more inotropic agents to maintain blood pressure and patients with acute or chronic kidney injury/failure, were also excluded from the study. INTERVENTION AND COMPARATOR: The study consists of four interventions and one comparator arm. All participants receive standard hospital care which includes airway support, anti-viral medication, antibiotics, fluid resuscitation, hemodynamic support, steroids, painkillers, and anti-pyretics. Randomised test patients will receive single dose of C-IVIG in following four dosage groups: Group 1: 0.15g/Kg with standard hospital care Group 2: 0.2g/Kg with standard hospital care Group 3: 0.25g/Kg with standard hospital care Group 4: 0.3g/Kg with standard hospital care Group 5 (comparator) will receive standard hospital care only MAIN OUTCOMES: The primary outcomes are assessment and follow-up of participants to observe 28-day mortality and, • the level and duration of assisted ventilation during hospital stay, • number of days to step down (shifting from ICU to isolation ward), • number of days to hospital discharge, • adverse events (Kidney failure, hypersensitivity with cutaneous or hemodynamic manifestations, aseptic meningitis, hemolytic anemia, leuko-neutropenia, transfusion related acute lung injury (TRALI)) during hospital stay, • change in C-Reactive Protein (CRP) levels, • change in neutrophil lymphocyte ratio to monitor inflammation. RANDOMISATION: Consenting participants who fulfill the criteria are allocated to either intervention or comparator arm with a ratio of 4:1, using sequentially numbered opaque sealed envelope simple randomization method. The participant allocated for intervention will be sequentially assigned dosage group 1-4 in ascending order. Participants will not be recruited in the next dosage group before a set number of participants in one group (10) are achieved. BLINDING (MASKING): Single blinded study, with participants blinded to allocation. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): Total 50 patients are randomised. The intervention arms consist of 40 participants divided in four groups of 10 participants while the comparator group consists of 10 patients. TRIAL STATUS: Current version of the protocol is "Version 2" dated 29th September, 2020. Participants are being recruited. Recruitment started on June, 2020 and is estimated to primarily end on January, 2021. TRIAL REGISTRATION: This trial was registered at ClinicalTrials.gov, NCT04521309 on 20 August 2020 and is retrospectively registered. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1).


Asunto(s)
Infecciones por Coronavirus/terapia , Inmunización Pasiva/métodos , Inmunoglobulinas Intravenosas , Neumonía Viral/terapia , Adulto , Betacoronavirus/aislamiento & purificación , COVID-19 , Enfermedad Crítica/terapia , Femenino , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Inmunoglobulinas Intravenosas/efectos adversos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/efectos adversos , Masculino , Pandemias , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Sueroterapia para COVID-19
13.
Bioresour Technol ; 283: 358-372, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30928198

RESUMEN

Water shortage, public health and environmental protection are key motives to treat wastewater. The widespread adoption of wastewater as a resource depends upon development of an energy-efficient technology. Anaerobic membrane bioreactor (AnMBR) technology has gained increasing popularity due to their ability to offset the disadvantages of conventional treatment technologies. However there are several hurdles, yet to climb over, for wider spread and scale-up of the technology. This paper reviews fundamental aspects of anaerobic digestion of wastewater, and identifies the challenges and opportunities to the further development of AnMBRs. Membrane fouling and its implications are discussed, and strategies to control membrane fouling are proposed. Novel AnMBR configurations are discussed as an integrated approach to overcome technology limitations. Energy demand and recovery in AnMBRs is analyzed. Finally key issues that require urgent attention to facilitate global penetration of AnMBR technology are highlighted.


Asunto(s)
Reactores Biológicos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Anaerobiosis , Eliminación de Residuos Líquidos/instrumentación
14.
Pulm Circ ; 3(2): 450, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24015352
15.
N Am J Med Sci ; 5(2): 119-23, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23641373

RESUMEN

BACKGROUND: HIV/AIDS has emerged as the single most formidable challenge to public health. School children of today are exposed to the risk of HIV/AIDS. AIMS: The study was conducted to determine the knowledge among secondary school students regarding HIV/AIDS and provide suggestions for HIV/AIDS education in schools. MATERIALS AND METHODS: A cross-sectional study was conducted among students of tenth to twelfth standard in the intermediate schools of Lucknow, India, from July to October 2011. A total of 215 students, both boys and girls, were enrolled in the study. RESULTS: In this study, for majority of the students (85%), the source of information about HIV/AIDS was the television. Regarding knowledge about modes of transmission of HIV/AIDS among girl students, 95.1% of them told that it is through unprotected sex. A total of 75.8% students said that it was transmitted from mother to child. CONCLUSION: It was observed that the knowledge of the school students was quite satisfactory for most of the variables like modes of transmission, including mother-to-child transmission of the disease. However, schools should come forward to design awareness campaigns for the benefit of the students.

16.
Pulm Circ ; 3(4): 851-5, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25006400

RESUMEN

Pulmonary arterial hypertension (PAH) is a major complication of sickle cell disease (SCD). Low levels of apolipoprotein A1 (Apo-A1) have been implicated in the development of PAH in SCD. We speculate that lower levels of Apo-A1 are related to dysregulation of the ubiquitin-proteasome pathway (UPP). Of 36 recruited patients with SCD, 14 were found to have PAH on the basis of right heart catheterization. Levels of Apo-A1 and Apo-B, polyubiquitin, total protease, and specific and normalized activity of chymotrypsin-like, trypsin-like, and caspase-like proteases in plasma were measured. Levels of Apo-A1 were found to be lower and polyubiquitin levels were found to be significantly higher in the PAH group ([Formula: see text]) in SCD. Apo-A levels were inversely correlated with polyubiquitin levels ([Formula: see text], [Formula: see text]). These results indicate that lower levels of Apo-A1 in SCD patients with PAH are likely related to enhance degradation by UPP, potentially contributing to pulmonary vascular pathology. These findings may provide significant insight in identifying suitable therapeutic targets in these patients.

17.
Pulm Circ ; 2(1): 54-60, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22558520

RESUMEN

Endothelial dysfunction plays an important role in the pathogenesis of pulmonary arterial hypertension (PAH) in sickle cell disease (SCD). A variety of evidence suggests that circulating endothelial progenitor cells (EPCs) play an integral role in vascular repair. We hypothesized that SCD patients with PAH are deficient in EPCs, potentially contributing to endothelial dysfunction and disease progression. The number of circulating CD34+/CD14-/CD106+ EPCs was significantly lower in SCD patients with PAH than without PAH (P=0.025). CD34+/CD14-/CD106+ numbers significantly correlated with tricuspid regurgitation velocity (TRV, r=-0.44, P=0.033) 6-minute walk distance (6MWD, r= 0.72, P=0.001), mean pulmonary artery pressure (mPAP, r= -0.43, P=0.05), and pulmonary vascular resistance (PVR, r=-0.45, P=0.05). Other EPC subsets including CD31+/CD133+/CD146+ were similar between both groups. Numbers of EPCs did not correlate with age, sex, hemoglobin, WBC count, reticulocyte count, lactate dehydrogenase (LDH), iron/ferritin levels, and serum creatinine. These data indicate that subsets of EPC are lower in SCD patients with PAH than in those without PAH. Fewer EPCs in PAH patients may contribute to the pulmonary vascular pathology. Reduced number of EPCs in SCD patients with PAH might not only give potential insight into the pathophysiological mechanisms but also might be useful for identifying suitable therapeutic targets in these patients.

18.
Am J Respir Cell Mol Biol ; 47(1): 94-103, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22362386

RESUMEN

Sphingomyelin (SM), a major sphingolipid in the lipid raft microdomains of the cell membrane, is synthesized by plasma membrane-bound sphingomyelin synthase 2 (SMS2). SMS2 is required for the maintenance of plasma membrane microdomain fluidity and receptor-mediated responses to inflammation in macrophages. However, the exact mechanism of SMS2 activation in endothelial barrier disruption and lung injury is not fully understood. To define the role of SMS activation in lung injury, we hypothesized that the inhibition of SM synthesis may provide protection against acute lung injury (ALI) by preserving endothelial barrier function. Using SMS2-silencing RNA (siRNA) treatment in human pulmonary endothelial cells (HPAECs) and tricyclodecan-9-yl-xanthogenate (D609), a competitive inhibitor of SMS, and phosphatidylcholine-specific phospholipase C in a murine model of bacterial LPS injury, we studied the role of sphingomyelin synthesis in ALI. Results show that pretreating mice with D609 significantly attenuated LPS-induced lung injury, as measured by a significant decrease in wet to dry ratio, bronchoalveolar lavage fluid cell and protein counts, and myeloperoxidase activity in lung tissue. Similarly, LPS-induced endothelial barrier disruption was significantly reduced in HPAECs pretreated with D609 or SMS2 siRNA, as demonstrated by an increase in paracellular integrity on an FITC-dextran assay, by the inhibition of LPS-induced stress fibers, and by the formation of cortical actin rings and lamellipodia at the periphery. These results indicate that D609 attenuates LPS-mediated endothelial barrier dysfunction and lung injury in mice through inhibition of SMS, suggesting a novel and essential role of SMS inhibition in modulating endothelial barrier integrity via actin cytoskeletal activation, with a potential therapeutic role in ALI.


Asunto(s)
Hidrocarburos Aromáticos con Puentes/farmacología , Citoesqueleto/metabolismo , Células Endoteliales/metabolismo , Lesión Pulmonar/metabolismo , Arteria Pulmonar/metabolismo , Esfingomielinas/biosíntesis , Tionas/farmacología , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo , Actinas/biosíntesis , Animales , Células Cultivadas , Humanos , Lipopolisacáridos/inmunología , Pulmón/irrigación sanguínea , Lesión Pulmonar/inducido químicamente , Ratones , Norbornanos , Interferencia de ARN , ARN Interferente Pequeño , Esfingomielinas/metabolismo , Tiocarbamatos , Transferasas (Grupos de Otros Fosfatos Sustitutos)/antagonistas & inhibidores , Transferasas (Grupos de Otros Fosfatos Sustitutos)/genética , Fosfolipasas de Tipo C/metabolismo
19.
Am J Physiol Lung Cell Mol Physiol ; 300(3): L430-40, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21191108

RESUMEN

Sphingomyelin synthase (SMS) catalyzes the synthesis of sphingomyelin (SM) and is required for maintenance of plasma membrane microdomain fluidity. Of the two isoforms of mammalian SMS, SMS1 is mostly present in the trans-Golgi apparatus, whereas SMS2 is predominantly found at the plasma membrane. SMS2 has a role in receptor mediated response to inflammation in macrophages, however, the role of SMS2 in vascular permeability, pulmonary edema, and lung injury have not been investigated. To define the role of SMS activation in lung injury, we utilized a lipopolysaccharide (LPS)-induced lung edema model. SMS activity was measured and correlated with the severity of lung injury. Within 4 h of LPS treatment, SMS activity was increased significantly and remained upregulated up to 24 h. Comparison of LPS-induced lung injury in SMS2 knockout (SMS2(-/-)) and wild-type littermate control mice showed that inflammation, cytokine induction, and lung injury were significantly inhibited in SMS2(-/-) mice. Our results suggest that a deficiency of SMS2 can diminish the extent of pulmonary edema and lung injury. Furthermore, we show that depletion of SMS2 was sufficient to decrease MAP kinase-JNK activation, severity of LPS-induced pulmonary neutrophil influx, and inflammation, suggesting a novel role of SMS2 activation in lung injury.


Asunto(s)
Lesión Pulmonar/enzimología , Lesión Pulmonar/patología , Transferasas (Grupos de Otros Fosfatos Sustitutos)/deficiencia , Actinas/metabolismo , Animales , Citoesqueleto/metabolismo , Células Endoteliales/enzimología , Células Endoteliales/patología , Activación Enzimática , Regulación Enzimológica de la Expresión Génica , Interleucina-6/metabolismo , Lipopolisacáridos , Pulmón/enzimología , Pulmón/patología , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/complicaciones , Ratones , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , FN-kappa B/metabolismo , Neumonía/complicaciones , Neumonía/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Esfingomielinas/biosíntesis , Factores de Tiempo , Transcripción Genética , Transferasas (Grupos de Otros Fosfatos Sustitutos)/antagonistas & inhibidores , Transferasas (Grupos de Otros Fosfatos Sustitutos)/genética , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
20.
Indian J Hematol Blood Transfus ; 27(2): 96-100, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22654300

RESUMEN

Serum uric acid (UA) is emerging as a strong and independent marker for pulmonary arterial hypertension (PAH). PAH is well recognized as a life threatening complication of sickle cell disease (SCD). However, the association between UA and PAH in SCD is unknown. We reviewed electronic medical records (EMR) of 559 consecutive adult SCD patients from Kings County Hospital Center (KCHC) between January 2005 and February 2010. Patients (n = 96) with measurement of UA in close temporal proximity to the transthoracic echocardiography (TTE) were identified. PAH was defined as pulmonary artery systolic pressure (PASP) ≥30 mm Hg. Patients (n = 16) with other risk factors which may cause PAH and chronic renal insufficiency were excluded. In 18 patients, TTE could not measure PASP. Finally, 62 patients were selected. Statistical analysis was performed using Student t tests, Pearson correlation coefficient and multivariate regression analysis. Out of 62 patients, 30 had PAH. Patients with PAH had a higher UA level (8.67 ± 4.8 vs. 5.35 ± 2.1, P = 0.001). We found strong positive correlation between the UA level and PASP (r = 0.71; P < 0.0001). This correlation was independent of diuretic use. UA could be a potential marker for PAH in SCD. However, its' prognostic and pathophysiologic role in SCD patients with PAH needs to be further investigated.

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