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A Network-DEA model to evaluate the impact of quality and access on hospital performance. ANNALS OF OPERATIONS RESEARCH 2023:1-31. [PMID: 37361087 PMCID: PMC10170039 DOI: 10.1007/s10479-023-05362-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 04/14/2023] [Indexed: 06/28/2023]
Abstract
The relationship between efficiency, quality, and access in healthcare is far from being well defined. In particular, there is no consensus on whether there is a trade-off between hospital performance and its social dimensions, such as the care appropriateness, safety, and access to proper health care. This study proposes a new approach based on the Network Data Envelopment Analysis (NDEA) to evaluate the existence of potential trade-offs between efficiency, quality, and access. The aim is to contribute for the heated debate around this topic with a novel approach. The suggested methodology combines a NDEA model with the weak disposability of outputs to handle with undesirable outputs related to the poor quality of care or the lack of access to appropriate and safe care. This combination results in a more realistic approach that has not yet been used to investigate this topic. We utilised data of the Portuguese National Health Service from 2016 to 2019, with four models and nineteen variables selected to quantify the efficiency, quality, and access to public hospital care in Portugal. A baseline efficiency score was calculated and compared with the performance scores obtained under two hypothetical scenarios to quantify the impact of each quality/access-related dimension on efficiency. The first scenario considers that each variable, individually, is at its best situation (for example, absence of septicaemia cases), and the second one, at its worst (e.g., all seen inpatients had a septicaemia case). The findings suggest that there might exist meaningful trade-offs between efficiency, quality, and access. Most variables exhibited a considerable and negative impact on the overall hospital efficiency. That is, we may expect a trade-off between efficiency and quality/access.
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Influence of 3 calcium channel blockers on gingival overgrowth in a population of severe refractory hypertensive patients. J Periodontal Res 2018; 53:721-726. [DOI: 10.1111/jre.12556] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2018] [Indexed: 12/12/2022]
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Measurement of Distance Between the Mental Foramina using ConeBeam Computed Tomography: A Pilot Study with a Possible Method for Planning Mandibular Implants. PESQUISA BRASILEIRA EM ODONTOPEDIATRIA E CLÍNICA INTEGRADA 2017. [DOI: 10.4034/pboci.2017.171.11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Subgingival bacterial community profiles in HIV-infected Brazilian adults with chronic periodontitis. J Periodontal Res 2015; 51:95-102. [PMID: 26040412 DOI: 10.1111/jre.12287] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2015] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND OBJECTIVE To compare the subgingival microbial diversity between non-HIV-infected and HIV-infected individuals with chronic periodontitis using denaturing gradient gel electrophoresis (DGGE). MATERIAL AND METHODS Thirty-two patients were selected: 11 were HIV-infected and 21 were non-HIV-infected, and all had chronic periodontitis. Periodontal measurements included probing depth, clinical attachment level, visible supragingival biofilm and bleeding on probing. Subgingival biofilm samples were collected from periodontal sites (50% with probing depth ≤ 4 mm and 50% with probing depth ≥ 5 mm) and whole-genomic-amplified DNA was obtained. The DNA samples were subjected to amplification of a 16S rRNA gene fragment using universal bacterial primers, followed by DGGE analysis of the amplified gene sequences. RESULTS The non-HIV-infected group presented higher mean full-mouth visible supragingival biofilm (p = 0.004), bleeding on probing (p = 0.006), probing depth (p < 0.001) and clinical attachment level (p = 0.001) in comparison with the HIV-infected group. DGGE analysis revealed 81 distinct bands from all 33 individuals. Banding profiles revealed a higher diversity of the bacterial communities in the subgingival biofilm of HIV-infected patients with chronic periodontitis. Moreover, cluster and principal component analyses demonstrated that the bacterial community profiles differed between these two conditions. High interindividual and intra-individual variability in banding profiles were observed for both groups. CONCLUSION HIV-infected patients with chronic periodontitis present greater subgingival microbial diversity. In addition, the bacterial communities associated with HIV-infected and non-HIV-infected individuals are different in structure.
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High prevalence of methicillin resistance and PVL genes among Staphylococcus aureus isolates from the nares and skin lesions of pediatric patients with atopic dermatitis. ACTA ACUST UNITED AC 2015; 48:588-94. [PMID: 25992644 PMCID: PMC4512096 DOI: 10.1590/1414-431x20154221] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 01/13/2015] [Indexed: 11/22/2022]
Abstract
Staphylococcus aureus is highly prevalent among patients with atopic
dermatitis (AD), and this pathogen may trigger and aggravate AD lesions. The aim of
this study was to determine the prevalence of S. aureus in the nares
of pediatric subjects and verify the phenotypic and molecular characteristics of the
isolates in pediatric patients with AD. Isolates were tested for antimicrobial
susceptibility, SCCmectyping, and Panton-Valentine Leukocidin (PVL)
genes. Lineages were determined by pulsed-field gel electrophoresis and multilocus
sequence typing (MLST). AD severity was assessed with the Scoring Atopic Dermatitis
(SCORAD) index. Among 106 patients, 90 (85%) presented S. aureus
isolates in their nares, and 8 also presented the pathogen in their skin infections.
Two patients had two positive lesions, making a total of 10 S.
aureusisolates from skin infections. Methicillin-resistant S.
aureus(MRSA) was detected in 24 (26.6%) patients, and PVL genes were
identified in 21 (23.3%), including 6 (75%) of the 8 patients with skin lesions but
mainly in patients with severe and moderate SCORAD values (P=0.0095). All 24 MRSA
isolates were susceptible to trimethoprim/sulfamethoxazole, while 8 isolates had a
minimum inhibitory concentration (MIC) to mupirocin >1024 μg/mL. High lineage
diversity was found among the isolates including USA1100/ST30, USA400/ST1,
USA800/ST5, ST83, ST188, ST718, ST1635, and ST2791. There was a high prevalence of
MRSA and PVL genes among the isolates recovered in this study. PVL genes were found
mostly among patients with severe and moderate SCORAD values. These findings can help
clinicians improve the therapies and strategies for the management of pediatric
patients with AD.
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Antimicrobial synergism against different lineages of methicillin-resistant Staphylococcus aureus carrying SCCmec IV. J Appl Microbiol 2014; 116:1418-26. [PMID: 24524649 DOI: 10.1111/jam.12472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/04/2014] [Accepted: 02/07/2014] [Indexed: 11/29/2022]
Abstract
AIM To evaluate the synergistic activity of antimicrobial drugs against lineages of methicillin-resistant Staphylococcus aureus (MRSA) carrying SCCmec IV. The biofilm production and related genes were also detected. METHODS AND RESULTS Forty two MRSA isolates were tested for biofilm production and related genes. Biofilm/biomass susceptibility to gentamicin (G), linezolid (L), rifampicin (R) and vancomycin (V) was determined for six isolates from three lineages prevalent in Rio de Janeiro hospitals in concentrations ranging from 0·25 to 64 μg ml(-1). Biomass was evaluated by microtitre plate test and number of viable cells (CFU cm(-2)) and inspected by epifluorescence microscopy. All isolates presented the icaA and sasG genes, but only 38% were biofilm producers. There were 50 and 45% biomass reductions when concentrations ≥4 μg ml(-1) of R or L and ≥16 μg ml(-1) of G or V, respectively, were used. Synergism tests produced a 55% biomass reduction with R(2μgml-1) + G(16μgml-1), R(2μgml-1) + L(2μgml-1), R(2μgml-1) + V(4μgml-1), and L(2μgml-1) + V(4μgml-1). Number of viable cells was reduced from 2 to 3 logs with R(2μgml-1) + L(2μgml-1) and R(2μgml-1) + V(4μgml-1). CONCLUSIONS Synergisms involving R plus L and R plus V caused important reductions in biofilm/biomass and the number of viable cells. Drug combinations should be considered in the chemotherapies of MRSA-SCCmec IV infections. SIGNIFICANCE AND IMPACT OF THE STUDY Biofilms in MRSA infections restrict the clinical choice of antimicrobials. Thus, knowledge of the best options for monotherapy and drug synergisms could improve clinical results.
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Meticillin-resistant Staphylococcus aureus: spread of specific lineages among patients in different wards at a Brazilian teaching hospital. J Hosp Infect 2013; 86:151-4. [PMID: 24433925 DOI: 10.1016/j.jhin.2013.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 12/04/2013] [Indexed: 11/17/2022]
Abstract
This study aimed to characterize meticillin-resistant Staphylococcus aureus (MRSA) lineages circulating in a Brazilian teaching hospital. MRSA isolates from nasal swabs were evaluated to assess antimicrobial susceptibility, staphylococcal cassette chromosome mec (SCCmec), Panton-Valentine leucocidin status, pulsed-field gel electrophoresis profile and multi-locus sequence type (MLST) analysis. Eighty-three MRSA isolates were analysed. SCCmec III (43.4%) and IV (49.4%) were predominant. ST1-IV (USA400) was more common in internal medicine (P = 0.002) whereas 'clone M' (SCCmec III) was more common in the medical and surgical intensive care unit (P = 0.004), and all isolates were ST5-IV (USA800) in dermatology (P < 0.001). These data improved the understanding of the MRSA epidemiology inside the hospital and helped to establish effective control measures.
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Loss of lingual sensitivity and slightly increased size signaling schwannoma in a patient with mixed conjunctive tissue disease. SPECIAL CARE IN DENTISTRY 2013; 33:301-3. [PMID: 24164229 DOI: 10.1111/j.1754-4505.2012.00308.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The purpose of this study was to describe an unusual case of a lingual schwannoma associated with a mixed connective tissue disease (MCTD). A case report. A lingual schwannoma with loss of lingual sensitivity and slightly increased size in an 18-year-old patient with MCTD was correctly diagnosed through a biopsy and no reoccurrence was observed one year after the surgical removal of the tumor and sensitivity returned 3 months after surgery. This case was considered uncommon, making the clinical diagnosis challenging in view of the diversity of possibilities for its differential diagnosis, thus showing the importance of a biopsy to confirm the diagnosis and long term follow up in such cases.
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Acute aortic dissection in pregnancy management with the fetus remaining in situ. J Cardiothorac Surg 2013. [PMCID: PMC3844844 DOI: 10.1186/1749-8090-8-s1-o255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Video-assisted surgery via periareolar, mitral valve replacement and papillary muscle relocation with neochordae of PTFE. J Cardiothorac Surg 2013. [PMCID: PMC3844747 DOI: 10.1186/1749-8090-8-s1-p144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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The first case report of non-nosocomial healthcare-associated infective endocarditis due to methicillin-resistant Staphylococcus aureus USA400 in Rio de Janeiro, Brazil. Infection 2013; 41:851-4. [PMID: 23456477 DOI: 10.1007/s15010-013-0430-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 02/12/2013] [Indexed: 11/26/2022]
Abstract
Staphylococcus aureus is the main causal pathogen of infective endocarditis (IE), which may have distinct origins, namely, community, nosocomial, or non-nosocomial healthcare-associated (NNHCA). We report the first case of NNHCA-IE caused by methicillin-resistant S. aureus strain USA400/SCCmec IV in which the combination therapy of rifampin and vancomycin had a favorable outcome for the patient.
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Clinical antimicrobial efficacy of NiTi rotary instrumentation with NaOCl irrigation, final rinse with chlorhexidine and interappointment medication: a molecular study. Int Endod J 2012; 46:225-33. [DOI: 10.1111/j.1365-2591.2012.02111.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Accepted: 07/05/2012] [Indexed: 12/01/2022]
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Short communication: polymicrobial community in teeth associated with severe early-childhood caries. Eur Arch Paediatr Dent 2011; 12:264-6. [PMID: 21993067 DOI: 10.1007/bf03262819] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM This was to characterise the microbial diversity in the complex dental plaque of children with severe early-childhood caries (S-ECC), using the denaturing gel gradient electrophoresis (DGGE) technique. METHODS The DGGE technique was used as a diagnostic tool to analyse samples from the oral cavity of a patient with S-ECC. Dental plaque samples from a 3-year-old child with S-ECC were taken from the primary central maxillary incisor (biofilm on vestibular surface), primary maxillary molar (biofilm on vestibular surface), primary central maxillary incisor (dentine), primary maxillary molar (dentine) and saliva and then analysed by PCR-DGGE. RESULTS Three bands occurred in all samples, moreover, 86% of similarity was observed in the pattern of bands between incisor and molar teeth biofilm samples, including four similar bands. CONCLUSION DGGE is a valuable tool for differentiating the microbial composition of the oral plaque in S-ECC children.
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Quality of management of oral anticoagulation as assessed by time in therapeutic INR range in elderly and younger patients with low mean years of formal education: a prospective cohort study. Age Ageing 2011; 40:375-81. [PMID: 21422013 DOI: 10.1093/ageing/afr020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND despite the overwhelming evidence of its effectiveness, oral anticoagulation continues to be underused in the elderly, presumably due to physicians' misconceptions when estimating bleeding risk and ability to comply with treatment. OBJECTIVE to investigate the quality of anticoagulation control among deprived elderly and younger patients. DESIGN prospective observational study. SETTING a public anticoagulation clinic in a developing country. SUBJECTS all adult patients on intended long-term (>90 days) oral anticoagulation. We studied 171 patients (79 elderly and 92 non-elderly) with a mean follow-up of 273 ± 84.9 days. METHODS the main outcome measure was the quality of anticoagulation management as measured by the time in therapeutic (TTR) international normalised ratio (INR) range. Elderly patients (≥60 years) were compared with younger patients with respect to the educational level and co-morbidities. RESULTS the mean number of years of formal education was 4.37 ± 3.2 years. The mean TTR was 62.50 ± 17.9% in non-elderly and 62.10 ± 16.6% in elderly (P = 0.862) subjects, despite the higher prevalence of co-morbidities in the latter group: heart failure (46.3 versus 28.6%, P = 0.042), diabetes mellitus (22.8 versus 8.7%, P = 0.011), renal failure (estimated glomerular filtration rate <50 ml/min: 38.0 versus 7.1%, P < 0.001) and polypharmacy (84.8 versus 58.7%, P < 0.001). Fifty elderly and 84 non-elderly subjects require little or no assistance in taking medications. Among them, the elderly had lower educational levels (3.42 ± 2.5 versus 5.55 ± 3.4 years of formal education, P < 0.001) and higher rates of cognitive impairment (34.0 versus 13.1%, P = 0.004), but a similar mean TTR (62.46 ± 16.1 versus 63.02 ± 17.8%, P = 0.856). The oldest (≥75 years) patients did as well as those aged ≤50 years (mean TTR: 62.54 ± 16.0 versus 62.23 ± 16.4%, respectively, P = 0.98). CONCLUSIONS good-quality management of oral anticoagulation is achievable in deprived populations attending an anticoagulation clinic. Elderly patients may experience similar quality of anticoagulation despite having higher levels of co-morbidities and polypharmacy. These results add evidence to the safety of such therapeutic interventions in the elderly.
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Chromosome mapping of retrotransposable elements Rex1 and Rex3 in three fish species in the subfamily Hypoptopomatinae (Teleostei, Siluriformes, Loricariidae). Cytogenet Genome Res 2010; 132:64-70. [PMID: 20798486 DOI: 10.1159/000319620] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2010] [Indexed: 11/19/2022] Open
Abstract
Transposons and retrotransposons represent a great portion of the eukaryotic genome. These repeated elements can be defined as genetic entities capable of self-inserting into different positions within the genome modifying the functions of the genes with which they are associated. The purpose of the present work was to isolate, identify, and map the sequences of Rex1 and Rex3 transposable elements present in the genomes of fishes of the family Loricariidae. The retrotransposable elements were identified through amplification with Rex1 and Rex3 primers, and the nucleotide composition of the retrotransposons was determined by automatic sequencing. In all the species analyzed it was possible to isolate Rex1 partial sequences from 520 to 563 bp in size and Rex3 partial sequences from 407 to 454 bp in size. Comparisons with the available literature showed that Loricariidae retrotransposons Rex1 and Rex3 have a high sequence similarity to putative homologous genes in different fish orders. Fluorescence in situ hybridization experiments conducted in 3 species, Hisonotus leucofrenatus, Pseudotocinclus tietensis, and Parotocinclus maculicauda, using the retrotransposable elements isolated for each species as probes, revealed that Rex1 and Rex3 share a similar dispersion pattern and are both found on all chromosomes of the 3 species organized in small clusters and dispersed on all the chromosomes, including euchromatic and heterochromatic regions, although a larger concentration was observed in the heterochromatic regions of H. leucofrenatus. The data found in the present study contradict much of the literature that substantiates that the retrotranspon elements are preferentially accumulated in the heterochromatin regions in fishes.
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Improving oral absorption of Salmon calcitonin by trimyristin lipid nanoparticles. J Biomed Nanotechnol 2010; 5:76-83. [PMID: 20055109 DOI: 10.1166/jbn.2009.443] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Solid lipid nanoparticles (SLN) composed of trimyristin (solid lipid) and poloxamer 407 (surfactant) were prepared by a w/o/w emulsion technique for the incorporation of Salmon calcitonin, and further explored as protein carriers for oral delivery. Trimyristin SLN showed a mean size diameter of 200 nm with an association efficiency for calcitonin of approx. 86%. The morphology of SLN was investigated by cryo-SEM and by AFM, revealing spheroid shape SLN with a smooth surface. The in vitro release of calcitonin occurred for a period of 8 h, under both gastric and intestinal simulated pH conditions, predicting suitable properties for oral administration. The pharmacological activity of the protein was evaluated following oral dosage of calcitonin-loaded SLN in rats. SLN lowered the basal blood calcium levels by up to 20% with 500 IU/kg dose sustaining hypocalcaemia over 8 h. The results indicate that incorporation of Salmon calcitonin into trimyristin SLN is a key factor for the improvement of the efficiency of such carriers for oral delivery of proteins.
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Minoxidil-loaded nanostructured lipid carriers (NLC): characterization and rheological behaviour of topical formulations. DIE PHARMAZIE 2009; 64:177-182. [PMID: 19348340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Lipid nanoparticles are used as biocompatible carriers for several types of drugs intended for pharmaceutical, cosmetic, and biochemical purposes. The wide range of lipids and surfactants available for the production of such particles turns these carriers highly suitable for distinct applications (topical, dermal and transdermal, parenteral, pulmonary, and oral administration). This work describes the development of a special type of lipid particles, namely nanostructured lipid carriers (NLC), for minoxidil as an alternative to conventional topical alcoholic solutions. NLC were composed of stearic acid and oleic acid, being the matrix stabilized with poloxamer 188 in aqueous dispersion. To develop a suitable topical formulation, lipid dispersions were further mixed with freshly prepared Carbopol or perfluorocarbon based hydrogels. Minoxidil-loaded NLC were approximately 250 nm in size before the entrapment within the gel network and remained below 500 nm after mixing with both types of hydrogels. The occurrence of minoxidil crystallization in the aqueous phase of lipid dispersions was discarded under analysis by light microscopy and by scanning electron microscopy. Differential scanning calorimetry was used to assess the recrystallization index (i.e. measure of the percentage of lipid matrix that is crystallized) of the particles, which was shown to be 62% for minoxidil-free dispersions and 68% for minoxidil-loaded NLC dispersions. Rheological analysis of hydrogels containing NLC dispersions showed typical pseudoplastic behaviour which makes them suitable for topical purposes.
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Insulin-loaded nanoparticles are prepared by alginate ionotropic pre-gelation followed by chitosan polyelectrolyte complexation. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2007; 7:2833-41. [PMID: 17685304 DOI: 10.1166/jnn.2007.609] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Alginate nanoparticles were prepared from dilute alginate sol by inducing a pre-gel with calcium counter ions, followed by polyelectrolyte complex coating with chitosan. Particles in the nanometer size range were obtained with 0.05% alginate and 0.9 mM Ca2+. The mean particle size was influenced by time and stirring speed of nanoparticle preparation, by alginate guluronic acid content and chitosan molecular weight and by the initial alginate:chitosan mass ratio. The association efficiency of insulin into alginate nanoparticles, as well as loading capacity were mainly influenced by the alginate:chitosan mass ratio. Under optimized size conditions, the association efficiency and loading capacities were as high as 92% and 14.3%, respectively. Approximately 50% of the protein was partially retained by the nanoparticles in gastric pH environment up to 24 hours while a more extensive release close to 75% was observed under intestinal pH conditions. Mild formulation conditions, optimum particle size range obtained, high insulin entrapment efficiency, and resistance to gastrointestinal release seem to be synergic and promising factors toward development of an oral insulin delivery form.
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Probing insulin's secondary structure after entrapment into alginate/chitosan nanoparticles. Eur J Pharm Biopharm 2006; 65:10-7. [PMID: 17101268 DOI: 10.1016/j.ejpb.2006.09.005] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 09/13/2006] [Accepted: 09/18/2006] [Indexed: 11/21/2022]
Abstract
The aim of the present study was to probe the structural integrity of insulin after being entrapped into chitosan/alginate nanoparticles produced by ionotropic polyelectrolyte pre-gelation. By manipulating the alginate:chitosan mass ratio and the pH during nanoparticle production, desired nanoparticles with a mean size of 850 (+/-88)nm and insulin association efficiency of 81 (+/-2)% were obtained. Insulin secondary structure was assessed by Fourier transform infrared (FTIR) and circular dichroism (CD) after entrapment into nanoparticles and after release from the particles under gastrointestinal simulated conditions. FTIR second-derivative spectra and area-overlap compared to an insulin standard confirmed that no significant conformational changes of insulin occurred in terms of alpha-helix and beta-sheet content. Far-UV-CD spectra corroborated the preservation of insulin structure during the nanoparticle production procedure. The presented nanoparticulate system is a promising carrier for insulin oral delivery since it preserves insulin structure and therefore also, potentially, its bioactivity.
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Quinacrine female nonsurgical sterilization (QS): endometrial assessment by vaginal ultrasonography in 128 women. Int J Gynaecol Obstet 2003; 83 Suppl 2:S59-66. [PMID: 14763187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
OBJECTIVE Investigate effectiveness, safety and endometrial pattern after QS. METHOD This study began in March 1999 and ended March 18, 2003; 128 women received transcervical insertions of quinacrine. Follow-up visits with ultrasound were scheduled at 1, 3, 6, 12-month intervals. RESULTS Two pregnancies occurred, one at 25 months, the other at 37. Adverse events (AE) were: yellow vaginal discharge, headache, mild abdominal pain, vaginal pruritus, nausea and transient decrease in endometrial thickness. One patient had allergic reaction. A third insertion was done in case of vaginal bleeding (16.4%). One year after QS 10% still had amenorrhea, which may be the result of the fact that 73% of our patients had received DMPH. Once inside the uterus, the dissolved quinacrine could be seen within seconds, via ultrasound as a "Lake of Quinacrine" which stays for up to two hours. Frequently, a transverse vaginal ultrasonographic view of the uterine cavity showed plug-like echogenic points at the cornua. CONCLUSION Quinacrine sterilization is safe and effective. The echogenic points need to be more thoroughly studied in order to affirm whether ultrasonography may identify the blockage of the tubes. Since early pregnancy is due to imperfect tubal closure, the use of ultrasound may prevent failure. However, pregnancy due to later recanalization cannot be avoided.
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Naproxen availability from variable-dose and weight sustained-release tablets. Drug Dev Ind Pharm 2001; 27:221-5. [PMID: 11291202 DOI: 10.1081/ddc-100000240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The aim of this work was to compare the naproxen availability from hydroxypropyl methylcellulose (HPMC) matrix tablets containing the same dose and a 2-fold weight variation (160 mg of naproxen in tablets weighting 250 and 500 mg) or with the same weight and a 2-fold dose variation (500 mg of weight and 160 or 320 mg of naproxen). The 2-fold weight variation in tablets with the same dose and also the 2-fold dose variation in tablets with the same weight did not affect the naproxen release. In addition, the release rate of two tablets of the same formulation and one tablet with a 2-fold dose and weight variation was not significantly different at the first minutes of the dissolution assay.
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Effect of hydroxypropyl methylcellulose and hydrogenated castor oil on naproxen release from sustained-release tablets. AAPS PharmSciTech 2001; 2:E6. [PMID: 14727881 PMCID: PMC2750472 DOI: 10.1208/pt020206] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2000] [Accepted: 04/02/2001] [Indexed: 11/30/2022] Open
Abstract
The effect of the concentration of hydrophilic (hydroxypropyl methylcellulose [HPMC]) and hydrophobic (hydrogenated castor oil [HCO]) products, fillers (lactose and dibasic calcium phosphate), and buffers (sodium bicarbonate, calcium carbonate, and sodium citrate) on naproxen release rate was studied. Matrix tablets were prepared by double compression, and in vitro dissolution tests were performed. The dissolution results showed that an increased amount of HPMC or hydrogenated castor oil resulted in reduced drug release. The inclusion of buffers in the HPMC matrix tablets enhanced naproxen release. For HCO tablets, only sodium bicarbonate enhanced naproxen release. The presence of lactose on HPMC matrix tablets did not show a significantly different result from that obtained with the formulation containing dibasic calcium phosphate as a filler. However, for the tablets containing HCO, the presence of lactose significantly enhanced the naproxen release rate. The matrix-forming materials in this study were suitable for use in sustained-release tablets containing naproxen. The drug release can be modulated by adding suitable amounts of diluents and buffers.
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Guidelines for the Department of Transportation physical examination. Nurse Pract 1999; 24:78, 81, 88-92 passim. [PMID: 10349671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Primary care providers commonly perform the mandatory Department of Transportation Federal Highway Administration physical examination for individuals who drive commercial motor vehicles. Although these examinations may be offered at the worksite or in occupational health clinics, many drivers prefer to have them performed in the primary care setting. Performing the examination and subsequently certifying the driver is a highly regulated process with potentially serious consequences for the driver, the examiner, and the public. This article discusses the regulations and recommendations for certification of commercial drivers and the problems commonly encountered in the clinical setting.
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[The cardiac toxicity of cancer chemotherapy]. ACTA MEDICA PORT 1994; 7:311-8. [PMID: 8073908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The presence of secondary effects following the administration of chemotherapeutic drugs is an important limitation to cancer therapy. Of these, cardiotoxicity is of crucial importance due to its negative influence on survival. The anthracyclines and cyclophosphamide are the most important cardiotoxic antineoplastic agents currently used. If we agree on a ceiling dosage of chemotherapy we will deprive some patients with a highly functional cardiac reserve of a potential benefit in the control of their cancer. Other patients who are more susceptible to the cardiotoxic effects of anticancer agents will suffer from severe cardiac disfunction following small cumulative doses of anthracyclines. The authors discuss the main cardiotoxic effects of several antineoplastic drugs with special attention given to the anthracycline group. Several diagnostic methods potentially useful in cardiac monitoring are described. Radionuclide angiocardiography is considered the gold-standard in monitoring anthracycline cardiotoxicity. Other invasive methods like endomyocardial biopsy and right heart catheterization can be clinically useful when nuclear angiocardiography is inconclusive. The authors propose an approach to the prevention of anthracycline cardiotoxicity. Other chemotherapeutic agents like cyclophosphamide are associated with the presence of myopericarditis which is sometimes fatal. The cardiotoxic effects of anticancer treatment with 5-fluorouracil, mitoxantrone, carmustine, amsacrine and interferon are less frequent and usually more benign. Finally we discuss bone marrow transplantation and its related cardiotoxicity.
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