ABSTRACT
Recent studies in Spain have shown that males, younger workers, and people involved in manual jobs had the highest risk of suffering a work-related eye injury (WREI). This study aims to assess the predictors of sick leave associated with WREI and to compare them with risk factors of initial injury. A retrospective and descriptive study of WREI that causes sick leave of one or more days among workers from an insurance labor mutual company in Spain was conducted over a period from 2008 to 2018. The variables of the study were sex, age, occupation, and type of injury. A total of 9352 (18.6% of 50,265 WREI) cases and 113,395 total days of sick leave were observed, with an estimated EUR 4,994,009.59 of associated labor cost. The main predictors of sick leave related to WREI were found to be female (highest incidence; 25.9 (95% CI (24.8-27.1))), >55 years of age (highest incidence; 20.5 (95% CI (19.3-21.7))), not working in the industry (lowest incidence; 13.8 (95% CI (13.3-14.2))), and not suffering "other disorders of conjunctiva" (lowest incidence; 5.7 (95% CI (4.7-6.8))). The consequences associated with WREI are worse for female and older workers, despite the main risk of suffering WREI being observed in males and younger workers.
Subject(s)
Eye Injuries , Sick Leave , Female , Humans , Male , Occupations , Retrospective Studies , Spain/epidemiologyABSTRACT
Objetivos: Analizar las diferencias en la evolución de las lesiones oculares en el trabajo entre las comunidades autónomas en España. Métodos: Se llevó a cabo un estudio descriptivo, retrospectivo y longitudinal de los accidentes laborales y las enfermedades profesionales de una Mutua Colaboradora de la Seguridad Social entre las diferentes comunidades autónomas españolas en el intervalo de tiempo de 2008-2018. Se analizaron aquellos accidentes que provocaron lesión en alguna estructura ocular, comparándose la incidencia por cada 100 000 asegurados y el riesgo relativo (RR) de sufrir una lesión ocular en el trabajo. Resultados: Se observó una disminución en la evolución de la incidencia de lesiones oculares en el trabajo en todas las comunidades, aunque con dos periodos diferenciados. El porcentaje de cambio anual disminuye en todas las comunidades hasta el 2013, pero entre 2013-2018 esta tendencia sólo se mantiene en Asturias, Castilla-La Mancha, Islas Canarias, Madrid, Murcia y Navarra. Castilla- La Mancha fue la comunidad autónoma con mayor incidencia (886.56/100 000) y riesgo relativo de sufrir una lesión ocular (RR 2.66; IC 95% 2.58 - 2.75), mientras Cataluña presentó la menor incidencia (82.25) y riesgo relativo (RR 0.25; IC 95 % 0.22 - 0.28). Conclusiones: Durante el periodo 2008-2018 se produce una disminución en la incidencia de lesiones oculares en el trabajo en todas las comunidades autónomas con un cambio de tendencia a partir del año 2013 (AU)
Objectives: To analyze the differences in work-related eye injury trends among the different Autonomous Communities in Spain. Methods: This was a descriptive, retrospective and longitudinal study based on a Social Security-affiliated mutual insurance company work injury and illness database for the period 2008-2018 that included all Spanish Autonomous Communities. Accidents that caused an injury to any ocular structure were analysed, and both the incidence of work-related eye-injuries per 100 000 insured workers and the relative risk of suffering an eye injury were compared. Results: We observed a general decrease in work-related eye injuries in all of the communities, although with two distinct time periods. The annual percentage change decrease occurred in all communities until 2013. From 2013 to 2018, however, this decreasing trend was only observed in Asturias, Castilla-La Mancha, Canary Islands, Madrid, Murcia and Navarra. Castilla-La Mancha was the Autonomous Community with the highest incidence (886.56/100.000), as well as the highest relative risk of suffering an eye injury (RR 2.66; IC 95% 2.58 - 2.75). At the other end, the lowest incidence (82.25/100.000) and RR (RR 0.247; IC 95 % 0.22 - 0.28) were observed in Catalonia. Conclusions: We observed a statistically significance decrease in the incidence and relative risk of work-related eye injuries in all Autonomous Communities over the study period, although this trend changed from 2013 onward (AU)
Subject(s)
Humans , Eye Diseases/epidemiology , Occupational Diseases/epidemiology , Accidents, Occupational/statistics & numerical data , Eye Injuries/epidemiology , Retrospective Studies , Longitudinal Studies , Spain/epidemiology , Risk Factors , IncidenceABSTRACT
PURPOSE: To evaluate the weight of intraocular lenses (IOLs) depending on their material, dioptric power, toricity, focality, and haptic design. METHODS: Twenty-eight different IOL models from nine different medical companies (a total of 38 IOLs) and 1 capsular tension ring (CTR) were evaluated. IOLs were weighed using a precision scale, in hydrated conditions, as an approximation to their intraocular status. RESULTS: Hydrophilic IOLs were heavier than hydrophobic lenses (p < 0.001). Regarding toricity, no statistical differences were found comparing toric to non-toric models (p=0.1). Likewise, no differences were found between multifocal IOLs and monofocal IOLs (p=0.19). Dioptric power did not affect IOL weight: IOLs of <15DP had similar weights to those of ≥15D and IOLs of ≥24D had similar weights to those of <24 D (p=0.86 and p=0.59, respectively). Plate-design IOLs were significantly heavier than 1-piece C-loop (p < 0.001), 3-piece C-loop (p < 0.001), and 4-haptic lenses (p=0.001). CONCLUSIONS: Of the characteristics analyzed that might influence IOL weight, lenses with hydrophilic material and plate-haptic design were found to be heavier. Toricity, focality, and dioptric power had no influence on IOL weight.
ABSTRACT
OBJECTIVES: To analyze the differences in work-related eye injury trends among the different Autonomous Communities in Spain. METHODS: This was a descriptive, retrospective and longitudinal study based on a Social Security-affiliated mutual insurance company work injury and illness database for the period 2008-2018 that included all Spanish Autonomous Communities. Accidents that caused an injury to any ocular structure were analysed, and both the incidence of work-related eye-injuries per 100 000 insured workers and the relative risk of suffering an eye injury were compared. RESULTS: We observed a general decrease in work-related eye injuries in all of the communities, although with two distinct time periods. The annual percentage change decrease occurred in all communities until 2013. From 2013 to 2018, however, this decreasing trend was only observed in Asturias, Castilla-La Mancha, Canary Islands, Madrid, Murcia and Navarra. Castilla-La Mancha was the Autonomous Community with the highest incidence (886.56/100.000), as well as the highest relative risk of suffering an eye injury (RR 2.66; IC 95% 2.58 - 2.75). At the other end, the lowest incidence (82.25/100.000) and RR (RR 0.247; IC 95 % 0.22 - 0.28) were observed in Catalonia. CONCLUSIONS: We observed a statistically significance decrease in the incidence and relative risk of work-related eye injuries in all Autonomous Communities over the study period, although this trend changed from 2013 onward.
OBJETIVOS: Analizar las diferencias en la evolución de las lesiones oculares en el trabajo entre las comunidades autónomas en España. MÉTODOS: Se llevó a cabo un estudio descriptivo, retrospectivo y longitudinal de los accidentes laborales y las enfermedades profesionales de una Mutua Colaboradora de la Seguridad Social entre las diferentes comunidades autónomas españolas en el intervalo de tiempo de 2008-2018. Se analizaron aquellos accidentes que provocaron lesión en alguna estructura ocular, comparándose la incidencia por cada 100 000 asegurados y el riesgo relativo (RR) de sufrir una lesión ocular en el trabajo. RESULTADOS: Se observó una disminución en la evolución de la incidencia de lesiones oculares en el trabajo en todas las comunidades, aunque con dos periodos diferenciados. El porcentaje de cambio anual disminuye en todas las comunidades hasta el 2013, pero entre 2013-2018 esta tendencia sólo se mantiene en Asturias, Castilla-La Mancha, Islas Canarias, Madrid, Murcia y Navarra. Castilla- La Mancha fue la comunidad autónoma con mayor incidencia (886.56/100 000) y riesgo relativo de sufrir una lesión ocular (RR 2.66; IC 95% 2.58 2.75), mientras Cataluña presentó la menor incidencia (82.25) y riesgo relativo (RR 0.25; IC 95 % 0.22 0.28). CONCLUSIONES: Durante el periodo 2008-2018 se produce una disminución en la incidencia de lesiones oculares en el trabajo en todas las comunidades autónomas con un cambio de tendencia a partir del año 2013.
Subject(s)
Eye Injuries , Eye Injuries/epidemiology , Eye Injuries/etiology , Humans , Incidence , Longitudinal Studies , Retrospective Studies , Spain/epidemiologyABSTRACT
OBJECTIVE: To describe the epidemiological characteristics and trends of work-related eye injuries (WREIs) in Spain over a 10-year period by sex, age and occupational sector. DESIGN AND SETTINGS: A descriptive, retrospective and longitudinal study based on data from workers insured by a labour insurance company in Spain from 2008 to 2018 was presented. The study considered the ratio of the number of WREI per 100 000 population and the relative risk of suffering an ocular injury. WREIs were characterised by sex, age and occupational sector of injured workers. PRIMARY AND SECONDARY OUTCOME MEASURES: Ratio of the number of WREI. PARTICIPANTS: In Spain, all workers are insured by a labour insurance company that provides cover in the event of work-related accidents. In this study, we have included all workers insured by one of these insurance companies, IBERMUTUA, with workers in all areas of Spain. RESULTS: The study included 50 265 WREI in the company over the 10-year period. Most of the injuries occurred in males (44 445; 88.4%), in 35-44 age group (15 992; 31.8%) and in industry workers (18 899; 42.6%). The average incidence was 429.75 per 100 000 workers insured and 4273.36 per 100 000 IBERMUTUA accidents (related and not related to eyes). Males, 16-24 age group and industry occupational sector group, have the highest incidence for WREI. The incidence of WREI decrease over the study period in all variables. Males have 6.56 (95% CI 6.38 to 6.75) times more risk of suffering WREI than females. 16-24 age group have 1.77 (95% CI 1.71 to 1.83) times more risk than in the group of workers older than 55. Finally, industry workers have 7.73 (95% CI 7.55 to 7.92) times more risk than services workers. CONCLUSIONS: The risks of suffering WREI is higher for males, younger and less experienced workers, and for those who works in a manual task.
Subject(s)
Eye Injuries , Occupational Injuries , Accidents, Occupational , Eye Injuries/epidemiology , Eye Injuries/etiology , Female , Humans , Longitudinal Studies , Male , Occupational Injuries/epidemiology , Retrospective Studies , Spain/epidemiologyABSTRACT
BACKGROUND: Several studies show a high percentage of eye injuries related to work compared to other origins. However, there are few studies that describe work-related eye injuries. METHODS: A descriptive, retrospective, and longitudinal study that describes the characteristics of work-related eye injuries in a group of insured workers. Eye injuries were classified according to the International Classification of Diseases (ICD-10) and analyzed over 10 years (2008-2018). RESULTS: Keratitis and conjunctivitis were the most prevalent injuries (26,674 (53.1%) and 15,906 (31.6%)). Keratitis and conjunctivitis also show the highest percentage of injury incidence per 100,000 insured workers in both sexes, any age group, and any occupation. The analysis of the cumulative percentage change and average annual percent change in incidences over ten years shows a decrease in the incidences of all injuries, except for other disorders of the eye and anexa. CONCLUSIONS: Most of the work-related eye injuries affect the most exposed eye structures in any line of work: the cornea and conjunctiva. Suitable protection of these eye structures will decrease the number of cases of work-related eye injuries.
Subject(s)
Eye Injuries , Accidents, Occupational , Adolescent , Adult , Eye Injuries/epidemiology , Female , Humans , Incidence , Longitudinal Studies , Male , Middle Aged , Retrospective Studies , Spain/epidemiology , Young AdultABSTRACT
No disponible
Subject(s)
Humans , Escherichia coli/pathogenicity , Escherichia coli Infections/epidemiology , Diarrhea/epidemiology , Epidemiologic StudiesSubject(s)
Diarrhea/epidemiology , Disease Outbreaks , Escherichia coli Infections/epidemiology , Gastroenteritis/epidemiology , Bacterial Typing Techniques , Diarrhea/microbiology , Escherichia coli/classification , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli/pathogenicity , Escherichia coli Infections/microbiology , Gastroenteritis/microbiology , Germany/epidemiology , Humans , Laboratories , Prevalence , Spain/epidemiology , Time Factors , Virulence/geneticsABSTRACT
BACKGROUND: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is now the most common cause of skin and skin structure infections (SSSI) in several world regions. In Argentina prospective, multicenter clinical studies have only been conducted in pediatric populations. OBJECTIVE: PRIMARY: describe the prevalence, clinical and demographic characteristics of adult patients with community acquired SSSI due to MRSA; secondary: molecular evaluation of CA-MRSA strains. Patients with MRSA were compared to those without MRSA. MATERIALS AND METHODS: Prospective, observational, multicenter, epidemiologic study, with molecular analysis, conducted at 19 sites in Argentina (18 in Buenos Aires) between March 2010 and October 2011. Patients were included if they were ≥ 14 years, were diagnosed with SSSI, a culture was obtained, and there had no significant healthcare contact identified. A logistic regression model was used to identify factors associated with CA-MRSA. Pulse field types, SCCmec, and PVL status were also determined. RESULTS: A total of 311 patients were included. CA-MRSA was isolated in 70% (218/311) of patients. Clinical variables independently associated with CA-MRSA were: presence of purulent lesion (OR 3.29; 95%CI 1.67, 6.49) and age <50 years (OR 2.39; 95%CI 1.22, 4.70). The vast majority of CA-MRSA strains causing SSSI carried PVL genes (95%) and were SCCmec type IV. The sequence type CA-MRSA ST30 spa t019 was the predominant clone. CONCLUSIONS: CA-MRSA is now the most common cause of SSSI in our adult patients without healthcare contact. ST30, SCCmec IV, PVL+, spa t019 is the predominant clone in Buenos Aires, Argentina.
Subject(s)
Community-Acquired Infections/epidemiology , Methicillin-Resistant Staphylococcus aureus/physiology , Skin/microbiology , Staphylococcal Skin Infections/diagnosis , Staphylococcal Skin Infections/epidemiology , Adult , Argentina/epidemiology , Community-Acquired Infections/diagnosis , Female , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
ObjetivoIdentificar los factores asociados a la aceptación por parte del paciente de la hospitalización a domicilio directamente desde el servicio de urgencias.Pacientes y métodosEstudio de cohortes prospectivo observacional de pacientes que, una vez visitados en urgencias, reunían criterios de ingreso en sala convencional, podían responder a una entrevista y disponían de un posible cuidador. Se tomó como variable dependiente la predisposición a aceptar o no un ingreso en hospitalización a domicilio. De cada paciente, como variables independientes se recogieron aspectos demográficos, factores de su estado de salud-comorbilidad y de su enfermedad actual, y percepciones psicosociales relacionadas con la hospitalización a domicilio. La relación entre variables se estableció por análisis de regresión logística múltiple.ResultadosSe realizaron 129 entrevistas. La predisposición a aceptar un ingreso en hospitalización a domicilio fue del 71%. Sólo las percepciones psicosociales del paciente, con independencia de sus aspectos demográficos e incluso de su estado de salud actual y comorbilidad, se relacionaron con la predisposición a aceptar un ingreso en hospitalización a domicilio, en concreto las adecuadas condiciones físicas del domicilio (odds ratio [OR]: 4,31; intervalo de confianza del 95% [IC95%]: 1,1815,78), la ausencia de miedo por tener que manejar el oxígeno (OR: 5,99; IC95%: 2,0517,52), la ausencia de miedo a una mala evolución clínica (OR: 6,07; IC95%: 1,9418,96) y la percepción de una mayor libertad de horarios (OR: 12,61; IC95%: 3,3148,01).ConclusionesLa hospitalización a domicilio tendría una buena aceptación si se ofreciera directamente en el Servicio de Urgencias como alternativa a la hospitalización convencional. Esta aceptación se asocia a percepciones psicosociales, que deberían tenerse en cuenta al ofrecer esta modalidad asistencial (AU)
AimTo identify the factors associated with patients acceptance of emergency department discharge directly to hospital-at-home care.Patients and methodsWe performed a prospective observational cohort study of patients seen at the emergency department who met the following inclusion criteria: need for hospital admission, ability to be interviewed, and availability of an informal caregiver. The dependent variable was defined as the predisposition to accept or refuse hospital-at-home care. For each patient, the following independent variables were recorded: demographic characteristics, health-related factors, comorbidities, current illness and psychosocial perceptions related to hospital-at-home care. The associations among the variables were tested by means of logistic regression analysis.ResultsWe included 129 patients. Seventy-one percent would have accepted hospital-at-home care. Acceptance of hospital-at-home care was associated with psychosocial perceptions only, independently of demographic characteristics, current illness severity and comorbidities. These psychosocial perceptions included adequate conditions at home (OR: 4.31; 95% CI: 1.1815.78), not being afraid of oxygen manipulation (OR: 5.99; 95% CI: 2.0517.52), lack of fear of a poor outcome (OR: 6.07; 95% CI: 1.9418.96) and the possibility of enjoying a more flexible schedule (OR: 12.61; 95% CI: 3.3148.01).ConclusionsHospital-at-home care would be well accepted by patients if offered in the emergency department as an alternative to conventional hospitalization. Acceptance depends on patients psychosocial perceptions, which should be assessed before this mode of care is proposed (AU)
Subject(s)
Humans , Male , Female , Aged , Patient Acceptance of Health Care/psychology , Patient Discharge , Home Care Services, Hospital-Based , Prospective StudiesABSTRACT
AIM: To identify the factors associated with patients' acceptance of emergency department discharge directly to hospital-at-home care. PATIENTS AND METHODS: We performed a prospective observational cohort study of patients seen at the emergency department who met the following inclusion criteria: need for hospital admission, ability to be interviewed, and availability of an informal caregiver. The dependent variable was defined as the predisposition to accept or refuse hospital-at-home care. For each patient, the following independent variables were recorded: demographic characteristics, health-related factors, comorbidities, current illness and psychosocial perceptions related to hospital-at-home care. The associations among the variables were tested by means of logistic regression analysis. RESULTS: We included 129 patients. Seventy-one percent would have accepted hospital-at-home care. Acceptance of hospital-at-home care was associated with psychosocial perceptions only, independently of demographic characteristics, current illness severity and comorbidities. These psychosocial perceptions included adequate conditions at home (OR: 4.31; 95% CI: 1.18-15.78), not being afraid of oxygen manipulation (OR: 5.99; 95% CI: 2.05-17.52), lack of fear of a poor outcome (OR: 6.07; 95% CI: 1.94-18.96) and the possibility of enjoying a more flexible schedule (OR: 12.61; 95% CI: 3.31-48.01). CONCLUSIONS: Hospital-at-home care would be well accepted by patients if offered in the emergency department as an alternative to conventional hospitalization. Acceptance depends on patients' psychosocial perceptions, which should be assessed before this mode of care is proposed.
Subject(s)
Emergency Service, Hospital , Home Care Services, Hospital-Based , Patient Acceptance of Health Care/psychology , Patient Discharge , Aged , Female , Humans , Male , Prospective StudiesABSTRACT
BACKGROUND: An interesting seed protein family with a role in preventing insect herbivory is the multi-gene, APA family encoding the alpha-amylase inhibitor, phytohemagglutinin and arcelin proteins of common bean (Phaseolus vulgaris). Variability for this gene family exists and has been exploited to breed for insect resistance. For example, the arcelin locus has been successfully transferred from wild to cultivated common bean genotypes to provide resistance against the bruchid species Zabrotes subfasciatus although the process has been hampered by a lack of genetic tools for and understanding about the locus. In this study, we analyzed linkage disequilibrium (LD) between microsatellite markers at the APA locus and bruchid resistance in a germplasm survey of 105 resistant and susceptible genotypes and compared this with LD in other parts of the genome. RESULTS: Microsatellite allele diversity was found to vary with each of the eight APA-linked markers analyzed, and two markers within the APA locus were found to be diagnostic for bruchid resistance or susceptibility and for the different arcelin alleles inherited from the wild accessions. Arc1 was found to provide higher levels of resistance than Arc5 and the markers in the APA locus were highly associated with resistance showing that introgression of this gene-family from wild beans provides resistance in cultivated beans. LD around the APA locus was found to be intermediate compared to other regions of the genome and the highest LD was found within the APA locus itself for example between the markers PV-atct001 and PV-ag004. CONCLUSIONS: We found the APA locus to be an important genetic determinant of bruchid resistance and also found that LD existed mostly within the APA locus but not beyond it. Moderate LD was also found for some other regions of the genome perhaps related to domestication genes. The LD pattern may reflect the introgression of arcelin from the wild into the cultivated background through breeding. LD and association studies for the arcelin gene, linked genes and other members of the APA family are essential for breaking linkage drag while maintaining high levels of bruchid resistance in common bean.
Subject(s)
Genetic Loci/genetics , Insecticides/metabolism , Linkage Disequilibrium/genetics , Phaseolus/genetics , Plant Proteins/genetics , Alleles , Animals , Coleoptera/physiology , Genetic Markers , Genome, Plant/genetics , Genotype , Microsatellite Repeats/genetics , Organ Size/genetics , Phenotype , Population DynamicsABSTRACT
Dermatomyositis (DM), polymyositis (PM), and sporadic inclusion-body myositis (sIBM) constitute a heterogeneous group of subacute or chronic acquired skeletal muscle diseases. Known as idiopathic inflammatory myopathies (IIM), they all share the presence of considerable weakness due to muscle inflammation and necrosis. Diagnosis is based on clinical findings, confirmed by laboratory examinations (serum muscle enzyme concentrations, autoantibodies against nuclear or cytoplasmatic antigens, electromyography, and muscle biopsy). Environmental exposures leading to immune activation in genetically susceptible individuals seem to be a probable pathogenic mechanism. Infectious agents, drugs, and ultraviolet radiation have been identified as a cause of the onset, exacerbation, or acceleration of these myopathies. Several case reports and population studies have been reported to support the relationship between inflammatory myopathy and the environment. Moreover, seasonal patterns of the onset of IIM have frequently been reported.
Subject(s)
Autoimmune Diseases/epidemiology , Muscular Diseases/epidemiology , Autoimmune Diseases/pathology , Dermatomyositis/epidemiology , Dermatomyositis/pathology , Humans , Muscle, Skeletal/pathology , Muscular Diseases/pathology , Myositis/epidemiology , Myositis/pathology , Myositis, Inclusion Body/epidemiology , Myositis, Inclusion Body/pathology , Polymyositis/epidemiology , Polymyositis/pathologyABSTRACT
The present report highlights the difficulties of particle shape characterizations of multiparticulate systems obtained using different image analysis techniques. The report describes and discusses a number of shape factors that are widely used in pharmaceutical research. Using photographs of 16 pellets of different shapes, obtained by extrusion-spheronization, we investigated how shape factor estimates vary depending on method of calculation, and among different software packages. The results obtained indicate that the algorithms used (both for estimation of basic dimensions such as perimeter and maximum diameter, and for estimation of shape factors on the basis of these basic dimensions) have marked influences on the shape factor values obtained. These findings suggest that care is required when comparing results obtained using different image analysis programs.
Subject(s)
Algorithms , Image Processing, Computer-Assisted/methods , Particulate Matter , Software , Chemistry, Pharmaceutical/methods , Chemistry, Pharmaceutical/standards , Image Processing, Computer-Assisted/standards , Particle Size , Particulate Matter/standards , PowdersABSTRACT
This study investigated the effects of various process variables on some of the shape factors most widely used in the morphological characterization of pharmaceutical particles (including circularity, aspect ratio, er, and the recently proposed Vr and Vp). After optimization of the illumination system and greyscale thresholds for discrimination of particle background, we evaluated the effects of process variables within the image capture and analysis system, including the image capture device (video or digital camera), image color information (24-bits-per-pixel RGB or 8-bits-per-pixel black and white), file type (JPG or TIFF), and JPG file compression ratio. A key aspect was evaluation of the effect of scaling factor (microm/pixel), dependent on real pixel size and optical magnification, on shape factor estimates. The results obtained indicate that accurate estimation of shape factors requires use of a scaling factor below a certain maximum; however, use of very low scaling factors will mean that the field of view is very small, so that it will contain very few particles, implying a time-consuming increase in the number of images that must be analyzed. Finally, we use statistical procedures to estimate the minimum number of particles that must be analyzed in order to provide accurate estimates of shape factors.
Subject(s)
Chemistry, Pharmaceutical/methods , Image Enhancement , Image Processing, Computer-Assisted , Microscopy, Video , Particle SizeABSTRACT
This study presents and evaluates two new form factors for the characterization of pharmaceutical microparticles using image analysis techniques. The first factor, denoted Vr, is mean percentage variation in radial chord length (for a large number of radial chords drawn at small angular intervals) with respect to mean radial chord length. The second factor, denoted Vp, is percentage deviation of measured perimeter from the perimeter of a circle with radius equal to the mean radial chord length of the particle. Considering both ideal shapes and real pharmaceutical particle populations, these factors are compared with other form factors widely used in pharmaceutical technology. Our results indicate that Vr and Vp allow effective assessment of whether the particles of a given population show pharmaceutically significant deviations from sphericity. The two factors additionally facilitate identification of the basic shapes of particle outlines (notably ellipsoid, rectangular, and irregular). These factors may thus be of value for the characterization and monitoring of pharmaceutical pelleting processes.
Subject(s)
Image Enhancement/methods , Powders/chemistry , Particle Size , Powders/analysis , SoftwareABSTRACT
Antimicrobianos
Resistencia bacteriana
ABSTRACT
Antimicrobianos
Resistencia bacteriana
