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1.
Adv Lab Med ; 5(2): 103-108, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38939196

ABSTRACT

Many aspects of the activity of a medical laboratory have to be documented so as to facilitate the maintenance of the ongoing quality of service. As a consequence, many documents, forms and reports are generated. The retention time for each of these has to be specified. In addition to medical laboratory reports as part of the patient's medical record, the medical laboratory has to retain many documents and specimens according to national legislation or guidance from professional organizations, if these exist. If not, the laboratory management needs to define a retention schedule, which shall define the storage conditions and period of storage, according to ISO 15189:2022 requirements for retention of general quality management documents and records. The EFLM Working Group on Accreditation and ISO/CEN standards provides here a proposal on retention periods of documentation and specimens based on a failure-mode-effects-analysis (FMEA) risk-based approach, a concept of risk reduction that has become an integral part of modern standards.

3.
FASEB Bioadv ; 5(12): 528-540, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38094158

ABSTRACT

Objectives: We sought to investigate whether the Dp16 mouse model of Down syndrome (DS) is more susceptible to severe and lethal respiratory tract infection by Streptococcus pneumoniae. Study Design: We infected controls and Dp16 mice with Streptococcus pneumoniae and measured survival rates. We compared cytokine production by primary lung cell cultures exposed to Streptococcus pneumoniae. We examined lung protein expression for interferon signaling related pathways. We characterized the histopathology and quantified the extent of bronchus-associated lymphoid tissue. Finally, we examined mouse tissues for the presence of oligomeric tau protein. Results: We found that the Dp16 mouse model of DS displayed significantly higher susceptibility to lethal respiratory infection with Streptococcus pneumoniae compared to control mice. Lung cells cultured from Dp16 mice displayed unique secreted cytokine profiles compared to control mice. The Dp16 mouse lungs were characterized by profound lobar pneumonia with massive diffuse consolidation involving nearly the entire lobe. Marked red hepatization was noted, and Dp16 mice lungs contained numerous bronchus-associated lymphoid tissues that were highly follicularized. Compared to uninfected mice, both control mice and Dp16 mice infected with Streptococcus pneumoniae showed evidence of oligomeric tau aggregates. Conclusions: Increased susceptibility to severe respiratory tract infection with Streptococcus pneumoniae in Dp16 mice closely phenocopies infection in individuals with DS. The increase does not appear to be linked to overexpression of mouse interferon genes syntenic to human chromosome 21.

4.
Microbiol Spectr ; 11(6): e0471722, 2023 Dec 12.
Article in English | MEDLINE | ID: mdl-37882564

ABSTRACT

IMPORTANCE: The main route of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission is airborne. However, there are few experimental systems that can assess the airborne transmission dynamics of SARS-CoV-2 in vivo. Here, we designed, built, and characterized a hamster transmission caging and exposure system that allows for efficient SARS-CoV-2 airborne transmission in Syrian hamsters without contributions from fomite or direct contact transmission. We successfully measured SARS-CoV-2 viral RNA in aerosols and demonstrated that SARS-CoV-2 is transmitted efficiently at either a 1:1 or 1:4 infected index to naïve recipient hamster ratio. This is meaningful as a 1:4 infected index to naïve hamster ratio would allow for simultaneous comparisons of various interventions in naïve animals to determine their susceptibility to infection by aerosol transmission of SARS-CoV-2. Our SARS-CoV-2 exposure system allows for testing viral airborne transmission dynamics and transmission-blocking therapeutic strategies against SARS-CoV-2 in Syrian hamsters.


Subject(s)
COVID-19 , SARS-CoV-2 , Cricetinae , Animals , Mesocricetus , Respiratory Aerosols and Droplets , Disease Models, Animal
6.
Article in English | MEDLINE | ID: mdl-37271610

ABSTRACT

OBJECTIVE: We developed a web-based tool to measure the amount and rate of skill acquisition in pediatric interproximal caries diagnosis among pre- and postdoctoral dental students and identified variables predictive for greater image interpretation difficulty. STUDY DESIGN: In this multicenter prospective cohort study, a convenience sample of pre- and postdoctoral dental students participated in computer-assisted learning in the interpretation of bitewing radiographs of 193 children. Participants were asked to identify the presence or absence of interproximal caries and, where applicable, locate the lesions. After every case, participants received specific visual and text feedback on their diagnostic performance. They were requested to complete the 193-case set but could complete enough cases to achieve a competency performance standard of 75% accuracy, sensitivity, and specificity. RESULTS: Of 130 participants, 62 (47.7%) completed all cases. The mean change from initial to maximal diagnostic accuracy was +15.3% (95% CI, 13.0-17.7), sensitivity was +10.8% (95% CI, 9.0-12.7), and specificity was +15.5% (95% CI, 12.9-18.1). The median number of cases completed to achieve competency was 173 (interquartile range, 82-363). Of these 62 participants, 45 (72.6%) showed overall improvement in diagnostic accuracy. Greater numbers of interproximal lesions (P < .001) and the presence of noninterproximal caries (P < .001) predicted greater interpretation difficulty. CONCLUSIONS: Computer-assisted learning led to improved diagnosis of interproximal caries on bitewing radiographs among pre- and postdoctoral dental students.


Subject(s)
Dental Caries , Humans , Child , Dental Caries/diagnostic imaging , Radiography, Bitewing , Prospective Studies , Computers
7.
Front Microbiol ; 14: 1212179, 2023.
Article in English | MEDLINE | ID: mdl-37293233

ABSTRACT

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has resulted in over 6.7 million deaths worldwide. COVID-19 vaccines administered parenterally via intramuscular or subcutaneous (SC) routes have reduced the severity of respiratory infections, hospitalization rates, and overall mortality. However, there is a growing interest in developing mucosally delivered vaccines to further enhance the ease and durability of vaccination. This study compared the immune response in hamsters immunized with live SARS-CoV-2 virus via SC or intranasal (IN) routes and assessed the outcome of a subsequent IN SARS-CoV-2 challenge. Results showed that SC-immunized hamsters elicited a dose-dependent neutralizing antibody response but of a significantly lower magnitude than that observed in IN-immunized hamsters. The IN challenge with SARS-CoV-2 in SC-immunized hamsters resulted in body weight loss, increased viral load, and lung pathology than that observed in IN-immunized and IN-challenged counterparts. These results demonstrate that while SC immunization renders some degree of protection, IN immunization induces a stronger immune response and better protection against respiratory SARS-CoV-2 infection. Overall, this study provides evidence that the route of primary immunization plays a critical role in determining the severity of a subsequent respiratory infection caused by SARS-CoV-2. Furthermore, the findings suggest that IN route of immunization may be a more effective option for COVID-19 vaccines than the currently used parenteral routes. Understanding the immune response to SARS-CoV-2 elicited via different immunization routes may help guide more effective and long-lasting vaccination strategies.

8.
Pediatr Dent ; 45(2): 113-116, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-37106539

ABSTRACT

PURPOSE: The purpose of this study was to compare one-year clinical outcomes of primary incisor strip crowns (SCs) and zirconia crowns (ZCs) and determine the frequency of pulp therapy associated with each technique. METHODS: Children aged 18 to 48 months were randomly assigned to a ZC group or SC group. Each incisor was rated as intact (I), damaged (D), or requiring treatment (TR) six and 12 months following placement. RESULTS: Seventy-six ZCs and 101 SCs were placed for 59 participants; ZCs were more likely to be rated I than SCs at six months (odds ratio [OR] equals 4.2; P=0.01) and 12 months (OR equals 4.0; P=0.02). There was no statistical difference in the frequency of pulp therapy between groups (OR equals 0.8; P=0.70). There were no deviations from treatment randomization in either group. CONCLUSIONS: Zirconia crowns were more likely than strip crowns to be rated as intact at six or 12 months after treatment. The frequency of pulp therapy was not statistically different between groups.


Subject(s)
Composite Resins , Incisor , Child , Humans , Feasibility Studies , Tooth, Deciduous , Zirconium , Crowns
9.
Am J Physiol Lung Cell Mol Physiol ; 323(3): L372-L389, 2022 09 01.
Article in English | MEDLINE | ID: mdl-35762590

ABSTRACT

The redox status of the cysteine-rich SARS-CoV-2 spike glycoprotein (SARS-2-S) is important for the binding of SARS-2-S to angiotensin-converting enzyme 2 (ACE2), suggesting that drugs with a functional thiol group ("thiol drugs") may cleave cystines to disrupt SARS-CoV-2 cell entry. In addition, neutrophil-induced oxidative stress is a mechanism of COVID-19 lung injury, and the antioxidant and anti-inflammatory properties of thiol drugs, especially cysteamine, may limit this injury. To first explore the antiviral effects of thiol drugs in COVID-19, we used an ACE-2 binding assay and cell entry assays utilizing reporter pseudoviruses and authentic SARS-CoV-2 viruses. We found that multiple thiol drugs inhibit SARS-2-S binding to ACE2 and virus infection. The most potent drugs were effective in the low millimolar range, and IC50 values followed the order of their cystine cleavage rates and lower thiol pKa values. To determine if thiol drugs have antiviral effects in vivo and to explore any anti-inflammatory effects of thiol drugs in COVID-19, we tested the effects of cysteamine delivered intraperitoneally to hamsters infected with SARS-CoV-2. Cysteamine did not decrease lung viral infection, but it significantly decreased lung neutrophilic inflammation and alveolar hemorrhage. We speculate that the concentration of cysteamine achieved in the lungs with intraperitoneal delivery was insufficient for antiviral effects but sufficient for anti-inflammatory effects. We conclude that thiol drugs decrease SARS-CoV-2 lung inflammation and injury, and we provide rationale for future studies to test if direct (aerosol) delivery of thiol drugs to the airways might also result in antiviral effects.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 Drug Treatment , Anti-Inflammatory Agents/pharmacology , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Cysteamine/pharmacology , Humans , Peptidyl-Dipeptidase A/metabolism , Pharmaceutical Preparations , SARS-CoV-2 , Sulfhydryl Compounds/pharmacology
10.
Sci Transl Med ; 14(658): eabn6868, 2022 08 17.
Article in English | MEDLINE | ID: mdl-35511920

ABSTRACT

Transmission-blocking strategies that slow the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and protect against coronavirus disease 2019 (COVID-19) are needed. We have developed an orally delivered adenovirus type 5-vectored SARS-CoV-2 vaccine candidate that expresses the spike protein. Here, we demonstrated that hamsters vaccinated by the oral or intranasal route had robust and cross-reactive antibody responses. We then induced a postvaccination infection by inoculating vaccinated hamsters with SARS-CoV-2. Orally or intranasally vaccinated hamsters had decreased viral RNA and infectious virus in the nose and lungs and experienced less lung pathology compared to mock-vaccinated hamsters after SARS-CoV-2 challenge. Naïve hamsters exposed in a unidirectional air flow chamber to mucosally vaccinated, SARS-CoV-2-infected hamsters also had lower nasal swab viral RNA and exhibited fewer clinical symptoms than control animals, suggesting that the mucosal route reduced viral transmission. The same platform encoding the SARS-CoV-2 spike and nucleocapsid proteins elicited mucosal cross-reactive SARS-CoV-2-specific IgA responses in a phase 1 clinical trial (NCT04563702). Our data demonstrate that mucosal immunization is a viable strategy to decrease SARS-CoV-2 disease and airborne transmission.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adenoviridae , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Clinical Trials, Phase I as Topic , Cricetinae , Humans , RNA, Viral , SARS-CoV-2 , Severity of Illness Index
11.
Front Neurol ; 12: 712060, 2021.
Article in English | MEDLINE | ID: mdl-34557147

ABSTRACT

Introduction: Stroke is the second most common cause of adult death in Africa. This study reports the demographics, stroke types, stroke care and hospital outcomes for stroke in Freetown, Sierra Leone. Methods: A prospective observational register recorded all patients 18 years and over with stroke between May 2019 and April 2020. Stroke was defined according to the WHO criteria. Pearson's chi-squared test was used to examine associations between categorical variables and unpaired t-tests for continuous variables. Multivariable logistic regression, to explain in-hospital death, was reported as odds ratios (ORs) and 95% confidence intervals. Results: Three hundred eighty-five strokes were registered, and 315 (81.8%) were first-in-a-lifetime events. Mean age was 59.2 (SD 13.8), and 187 (48.6%) were male. Of the strokes, 327 (84.9%) were confirmed by CT scan. Two hundred thirty-one (60.0%) were ischaemic, 85 (22.1%) intracerebral haemorrhage, 11 (2.9%) subarachnoid haemorrhage and 58 (15.1%) undetermined stroke type. The median National Institutes of Health Stroke Scale on presentation was 17 [interquartile range (IQR) 9-25]. Haemorrhagic strokes compared with ischaemic strokes were more severe, 20 (IQR 12-26) vs. 13 (IQR 7-22) (p < 0.001), and occurred in a younger population, mean age 52.3 (SD 12.0) vs. 61.6 (SD 13.8) (p < 0.001), with a lower level of educational attainment of 28.2 vs. 40.7% (p = 0.04). The median time from stroke onset to arrival at the principal referral hospital was 25 hours (IQR 6-73). Half of the patients (50.4%) sought care at another health provider prior to arrival. One hundred fifty-one patients died in the hospital (39.5%). Forty-three deaths occurred within 48 hours of arriving at the hospital, with median time to death of 4 days (IQR 0-7 days). Of the patients, 49.6% had ≥1 complication, 98 (25.5%) pneumonia and 33 (8.6%) urinary tract infection. Male gender (OR 3.33, 1.65-6.75), pneumonia (OR 3.75, 1.82-7.76), subarachnoid haemorrhage (OR 43.1, 6.70-277.4) and undetermined stroke types (OR 6.35, 2.17-18.60) were associated with higher risk of in-hospital death. Discussion: We observed severe strokes occurring in a young population with high in-hospital mortality. Further work to deliver evidence-based stroke care is essential to reduce stroke mortality in Sierra Leone.

12.
bioRxiv ; 2021 Nov 11.
Article in English | MEDLINE | ID: mdl-33330868

ABSTRACT

Neutrophil-induced oxidative stress is a mechanism of lung injury in COVID-19, and drugs with a functional thiol group ("thiol drugs"), especially cysteamine, have anti-oxidant and anti-inflammatory properties that could limit this injury. Thiol drugs may also alter the redox status of the cysteine-rich SARS-CoV-2 spike glycoprotein (SARS-2-S) and thereby disrupt ACE2 binding. Using ACE2 binding assay, reporter virus pseudotyped with SARS-CoV-2 spikes (ancestral and variants) and authentic SARS-CoV-2 (Wuhan-1), we find that multiple thiol drugs inhibit SARS-2-S binding to ACE2 and virus entry into cells. Pseudoviruses carrying variant spikes were less efficiently inhibited as compared to pseudotypes bearing an ancestral spike, but the most potent drugs still inhibited the Delta variant in the low millimolar range. IC50 values followed the order of their cystine cleavage rates and lower thiol pKa values. In hamsters infected with SARS-CoV-2, intraperitoneal (IP) cysteamine decreased neutrophilic inflammation and alveolar hemorrhage in the lungs but did not decrease viral infection, most likely because IP delivery could not achieve millimolar concentrations in the airways. These data show that thiol drugs inhibit SARS-CoV-2 infection in vitro and reduce SARS-CoV-2-related lung injury in vivo and provide strong rationale for trials of systemically delivered thiol drugs as COVID-19 treatments. We propose that antiviral effects of thiol drugs in vivo will require delivery directly to the airways to ensure millimolar drug concentrations and that thiol drugs with lower thiol pKa values are most likely to be effective.

13.
Clin Chem Lab Med ; 57(4): 459-464, 2019 03 26.
Article in English | MEDLINE | ID: mdl-30511927

ABSTRACT

ISO15189:2012 requires medical laboratories to document metrological traceability of their results. While the ISO17511:2003 standard on metrological traceability in laboratory medicine requires the use of the highest available level in the traceability chain, it recognizes that for many measurands there is no reference above the manufacturer's selected measurement procedure and the manufacturer's working calibrator. Some immunoassays, although they intend to measure the same quantity and may even refer to the same reference material, unfortunately produce different results because of differences in analytical selectivity as manufacturers select different epitopes and antibodies for the same analyte. In other cases, the cause is the use of reference materials, which are not commutable. The uncertainty associated with the result is another important aspect in metrological traceability implementation. As the measurement uncertainty on the clinical samples is influenced by the uncertainty of all steps higher in the traceability chain, laboratories should be provided with adequate and appropriate information on the uncertainty of the value assignment to the commercial calibrators that they use. Although the between-lot variation in value assignment will manifest itself as part of the long-term imprecision as estimated by the end-user, information on worst-case to be expected lot-lot variation has to be communicated to the end-user by the IVD provider. When laboratories use ancillary equipment that potentially could have a critical contribution to the reported results, such equipment needs verification of its proper calibration and criticality to the result uncertainty could be assessed by an approach based on risk analysis, which is a key element of ISO15189:2012 anyway. This paper discusses how the requirement for metrological traceability as stated in ISO15189 should be met by the medical laboratory and how this should be assessed by accreditation bodies.


Subject(s)
Consensus , Medical Laboratory Science/standards , Calibration , Humans , Quality Control , Reference Standards , Uncertainty
14.
J Clin Invest ; 128(12): 5428-5433, 2018 12 03.
Article in English | MEDLINE | ID: mdl-30277472

ABSTRACT

In the era of combined antiretroviral therapy (cART), lung diseases such as chronic bronchitis (CB) and chronic obstructive pulmonary disease (COPD) are common among persons living with HIV (PLWH), particularly smokers. Although smoking is highly prevalent among PLWH, HIV may be an independent risk factor for lung diseases; however, the role of HIV and cigarette smoke (CS) and their potential interaction in the development of chronic lung diseases among PLWH has not been delineated. To investigate this interaction, cynomolgus macaques were exposed to CS and/or simian-adapted human immunodeficiency virus (SHIV) and treated with cART. The development of CB and the lung functions were evaluated following CS±SHIV treatment. The results showed that in the lung, SHIV was a strong independent risk factor for goblet cell metaplasia/hyperplasia and mucus formation, MUC5AC synthesis, loss of tight junction proteins, and increased expression of Th2 cytokines/transcription factors. In addition, SHIV and CS synergistically reduced lung function and increased extrathoracic tracheal ring thickness. Interestingly, SHIV infection generated significant numbers of HIV-gp120+ epithelial cells (HGECs) in small airways and alveoli, and their numbers doubled in CS+SHIV-infected lungs. We conclude that even with cART, SHIV independently induces CB and pro-COPD changes in the lung, and the effects are exacerbated by CS.


Subject(s)
Cigarette Smoking , HIV Infections , HIV-1 , Lung , Pulmonary Alveoli , Pulmonary Disease, Chronic Obstructive , Animals , Cigarette Smoking/adverse effects , Cigarette Smoking/pathology , Cigarette Smoking/physiopathology , HIV Infections/pathology , HIV Infections/physiopathology , Lung/pathology , Lung/physiopathology , Lung/virology , Macaca fascicularis , Pulmonary Alveoli/pathology , Pulmonary Alveoli/physiopathology , Pulmonary Alveoli/virology , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/virology
15.
J Can Dent Assoc ; 84: i5, 2018 05.
Article in English | MEDLINE | ID: mdl-31199722

ABSTRACT

OBJECTIVES: To determine the number and diagnoses of caries-related complaints presenting at Canada's largest children's hospital emergency department (ED) and the costs associated with treatment over 5 years. METHODS: We carried out a retrospective review of the health records of all children who presented to The Hospital for Sick Children, Toronto, with caries-related emergency complaints from 1 January 2008 to 31 December 2012. A caries-related complaint was defined as a chief complaint of pain or swelling resulting from the sequelae of dental decay (reversible pulpitis, irreversible pulpitis, abscess or cellulitis), as recorded in the chart by the treating physician or dentist. Visit information included chief complaint, final diagnosis, treatment rendered and patient disposition at discharge. Decision Support Services, a hospital department that analyzes resource use and associated costs, calculated the institutional costs for the episodes of emergency care. RESULTS: There were 1081 visits over the 5-year period, with a 19% increase in visits over that time. The most common presenting complaint was pain (50.8%) and the most common diagnosis abscess (35.6%). A dentist was consulted for 60.0% of the children and dental treatment in the ED was provided for 25.9%. The mean cost of treatment per patient was Can$575.17 (95% confidence interval $501.91-$648.43). CONCLUSIONS: Over the 5-year study period, dental visits to this tertiary care pediatric hospital increased. The most common complaint was pain, and the diagnosis for about a third of these cases was abscess. Dental consultation was often included in the management of these patients and the resultant cost of these visits was about Can$600/patient.


Subject(s)
Dental Caries , Emergency Service, Hospital , Canada , Cellulitis , Child , Humans , Retrospective Studies
16.
Vaccines (Basel) ; 5(3)2017 Sep 19.
Article in English | MEDLINE | ID: mdl-28925950

ABSTRACT

Nucleolin (NCL) has been reported as a cellular receptor for the human respiratory syncytial virus (RSV). We studied the effects of re-purposing AS1411, an anti-cancer compound that binds cell surface NCL, as a possible novel strategy for RSV therapy in vitro and in vivo. AS1411 was administered to RSV-infected cultures of non-polarized (HEp-2) and polarized (MDCK) epithelial cells and to virus-infected mice and cotton rats. Results of in vitro experiments showed that AS1411, used in micromolar concentrations, was associated with decreases in the number of virus-positive cells. Intranasal administration of AS1411 (50 mg/kg) to RSV-infected mice and cotton rats was associated with partial reductions in lung viral titers, decreased virus-associated airway inflammation, and decreased IL-4/IFN-γ ratios when compared to untreated, infected animals. In conclusion, our findings indicate that therapeutic use of AS1411 has modest effects on RSV replication and host response. While the results underscore the challenges of targeting cell surface NCL as a potential novel strategy for RSV therapy, they also highlight the potential of cell surface NCL as a therapeutic target.

17.
Theranostics ; 7(14): 3573-3584, 2017.
Article in English | MEDLINE | ID: mdl-28912896

ABSTRACT

Rationale: Ultrasound-mediated opening of the Blood-Brain Barrier(BBB) has shown exciting potential for the treatment of Alzheimer's disease(AD). Studies in transgenic mouse models have shown that this approach can reduce plaque pathology and improve spatial memory. Before clinical translation can occur the safety of the method needs to be tested in a larger brain that allows lower frequencies be used to treat larger tissue volumes, simulating clinical situations. Here we investigate the safety of opening the BBB in half of the brain in a large aged animal model with naturally occurring amyloid deposits. Methods: Aged dogs naturally accumulate plaques and show associated cognitive declines. Low-frequency ultrasound was used to open the BBB unilaterally in aged beagles (9-11yrs, n=10) in accordance with institutionally approved protocols. Animals received either a single treatment or four weekly treatments. Magnetic resonance imaging(MRI) was used to guide the treatments and assess the tissue effects. The animals underwent neurological testing during treatment follow-up, and a follow-up MRI exam 1 week following the final treatment. Results: The permeability of the BBB was successfully increased in all animals (mean enhancement: 19±11% relative to untreated hemisphere). There was a single adverse event in the chronic treatment group that resolved within 24 hrs. Follow-up MRI showed the BBB to be intact with no evidence of tissue damage in all animals. Histological analysis showed comparable levels of microhemorrhage between the treated and control hemispheres in the prefrontal cortex (single/repeat treatment: 1.0±1.4 vs 0.4±0.5/5.2±1.8 vs. 4.0±2.0). No significant differences were observed in beta-amyloid load (single/repeat: p=0.31/p=0.98) although 3/5 animals in each group showed lower Aß loads in the treated hemisphere. Conclusion: Whole-hemisphere opening of the BBB was well tolerated in the aged large animal brain. The treatment volumes and frequencies used are clinically relevant and indicate safety for clinical translation. Further study is warranted to determine if FUS has positive effects on naturally occurring amyloid pathology.


Subject(s)
Aging/metabolism , Blood-Brain Barrier/metabolism , Capillary Permeability , Plaque, Amyloid/therapy , Ultrasonic Therapy/methods , Aging/pathology , Animals , Blood-Brain Barrier/growth & development , Dogs , Ultrasonic Therapy/adverse effects
18.
J Aerosol Med Pulm Drug Deliv ; 30(5): 299-321, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28277892

ABSTRACT

BACKGROUND: Aerosol delivery of chemotherapeutic nanocarriers represents a promising alternative for lung cancer therapy. This study optimized gemcitabine (Gem)-loaded gelatin nanocarriers (GNCs) cross-linked with genipin (Gem-GNCs) to evaluate their potential for nebulized lung cancer treatment. METHODS: Gem-GNCs were prepared by two-step desolvation and optimized through Taguchi design and characterized for physicochemical properties. Particle size and morphology were confirmed by scanning and transmission electron microscopy. In vitro release of Gem from Gem-GNCs performed in Dulbecco's phosphate-buffered saline and simulated lung fluid was evaluated to determine release mechanisms. Particle size stability was assessed under varying pH. Differential scanning calorimetry and powder X-ray diffraction were used to determine the presence and stability of Gem-GNC components and amorphization of Gem, respectively. Gem-GNC efficacy within A549 and H460 cells was evaluated using MTT assays. Mucus rheology upon treatment with Gem-GNCs, lactose, and normal saline control was measured. Andersen cascade impaction identified the aerodynamic particle size distribution of the nebulized formulation. RESULTS: Gem-GNCs had particle size, zeta potential, entrapment efficiency, and loading efficiency of 178 ± 7.1 nm, -18.9 mV, 92.5%, and 9.1%, respectively. The Gem and formulation excipients where molecularly dispersed and configured amorphously. Gem-GNCs were stable at pH 5.4-7.4 for 72 hours. Gem release from Gem-GNCs was governed by non-Fickian controlled release due to diffusion/erosion from a matrix-based nanocarrier. Gem-GNCs elicited a 40% reduction of the complex viscosity η*(1 Hz) of human bronchial epithelial cell mucus containing 3 wt% solids to mimic mild airway disease. The nebulized Gem-GNCs had a mass median aerodynamic diameter (MMAD) of 2.0 ± 0.16 µm, geometric standard deviation (GSD) of 2.7 ± 0.16, and fine particle fraction (FPF) of 75.2% ± 2.4%. The Gem-GNC formulation did not outperform the Gem solution in A549 cells. However, in H460, Gem-GNCs outperformed the Gem IC50 reduction by ∼5-fold at 48 and 10-fold 72 hours. CONCLUSION: Stable, effective, and sustained-release Gem-GNCs were developed. The nebulized Gem-GNCs had satisfactory MMAD, GSD, and FPF and the formulation reduced the dynamic complex viscosity of mucus consistent with increased mobility of nanoparticles.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Deoxycytidine/analogs & derivatives , Drug Delivery Systems , Lung Neoplasms/drug therapy , A549 Cells , Administration, Inhalation , Aerosols , Calorimetry, Differential Scanning , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Chemistry, Pharmaceutical/methods , Delayed-Action Preparations , Deoxycytidine/administration & dosage , Deoxycytidine/chemistry , Deoxycytidine/pharmacology , Drug Liberation , Gelatin , Humans , Lung Neoplasms/pathology , Nanoparticles , Particle Size , Viscosity , X-Ray Diffraction , Gemcitabine
19.
Pediatr Dent ; 39(1): 34-38, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-28292339

ABSTRACT

PURPOSE: The purpose of this study was to compare outcomes and survival of ferric sulfate with mineral trioxide aggregate (FS+MTA) pulpotomy and root canal therapy (RCT) in carious vital primary maxillary incisors. METHODS: In this parallel group noninferiority trial, asymptomatic carious vital primary incisors with pulp exposure in healthy 18- to 46-month-olds were allocated randomly to receive FS+MTA pulpotomy or RCT between September 2010 and September 2012. Each incisor was classified into one of the following radiographic outcomes: N (incisor without pathologic change); Po (pathologic change present, follow-up recommended); Px (pathologic change present, extract.) Clinical findings and incisor survival were secondary outcomes. RESULTS: Seventy subjects were enrolled with a total of 172 incisors. Twelve- and 18-month radiographic outcomes demonstrated no statistical difference between FS+MTA pulpotomy and RCT incisors for Px outcomes (P=0.38; odds ratio equals 0.60; 95 percent confidence interval equals 0.19 to 1.89; chi-square test). There was no statistical differences in clinical outcomes for FS+MTA pulpotomy and RCT at 12 and 18 months (P=0.51; Fisher's exact test) or survival for FS+MTA pulpotomy and RCT incisors (P=0.11; log-rank test). CONCLUSIONS: Ferric Sulfate with Mineral Trioxide Aggregate (FS+MTA) is an alternative to RCT for vital primary incisors.


Subject(s)
Aluminum Compounds/therapeutic use , Calcium Compounds/therapeutic use , Eugenol/therapeutic use , Ferric Compounds/therapeutic use , Incisor/surgery , Oxides/therapeutic use , Pulpectomy/methods , Pulpotomy/methods , Silicates/therapeutic use , Zinc Oxide/therapeutic use , Child, Preschool , Drug Combinations , Female , Humans , Infant , Male , Maxilla , Root Canal Therapy/methods , Tooth, Deciduous/surgery
20.
Neurobiol Aging ; 49: 86-99, 2017 01.
Article in English | MEDLINE | ID: mdl-27776266

ABSTRACT

Beta-amyloid (Aß) immunotherapy is a promising intervention to slow Alzheimer's disease. Aging dogs naturally accumulate Aß and show cognitive decline. An active vaccine against fibrillar Aß 1-42 (VAC) in aged beagles resulted in maintenance but not improvement of cognition along with reduced brain Aß. Behavioral enrichment (ENR) led to cognitive benefits but no reduction in Aß. We hypothesized cognitive outcomes could be improved by combining VAC with ENR in aged dogs. Aged dogs (11-12 years) were placed into 4 groups: (1) control/control (C/C); (2) control/VAC (C/V); (3) ENR/control (E/C); and (4) ENR/VAC (E/V) and treated for 20 months. VAC decreased brain Aß, pyroglutamate Aß, increased cerebrospinal fluid Aß 42 and brain-derived neurotrophic factor RNA levels but also increased microhemorrhages. ENR reduced brain Aß and prevented microhemorrhages. The combination treatment resulted in a significant maintenance of learning over time, reduced Aß, and increased brain-derived neurotrophic factor mRNA despite increased microhemorrhages; however, there were no benefits to memory. These results suggest that the combination of immunotherapy with behavioral enrichment leads to cognitive maintenance associated with reduced neuropathology that may benefit people with Alzheimer's disease.


Subject(s)
Aging/metabolism , Aging/psychology , Alzheimer Disease/therapy , Alzheimer Vaccines/therapeutic use , Amyloid beta-Peptides/immunology , Amyloid beta-Peptides/metabolism , Cerebral Hemorrhage/prevention & control , Cognition , Cognitive Behavioral Therapy/methods , Immunotherapy , Peptide Fragments/immunology , Peptide Fragments/metabolism , Alzheimer Disease/etiology , Alzheimer Disease/pathology , Amyloid beta-Peptides/cerebrospinal fluid , Animals , Brain/metabolism , Brain/pathology , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/metabolism , Dogs , Helplessness, Learned , Peptide Fragments/cerebrospinal fluid , RNA, Messenger/metabolism
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