Two-step hot isostatic pressing densification achieved non-porous fully-densified wood with enhanced physical and mechanical properties.

A new two-step densification method for wooden materials entitled hot isostatic pressing (HIP) is proposed. This method has the advantage over previous densification methods that can achieved almost the full densification of wood, reaching values up to 1.47 kg/m3, which exceeds any value ever reported for a hardwood species. Furthermore, it can preserve about 35% of the original volume, in comparison to other methods which typically can preserve only 20% of the volume. Although not tested in this investigation, in principle, the HIP method should be capable of densifying any shape of wood including circular and tubular cross sections because the main densification mechanism is based on gas pressure that is equally exerted in the entire surface, rather than localized mechanical compression, which can only be effective with rectangular cross sections. In the first stage of the two-step proposed method, the compressive strength of the anatomical wood structure is reduced by delignification, and, in the second, a full densification is achieved by hot isostatic pressing under argon atmosphere. Three tropical hardwood species with distinct anatomical characteristics and properties were used to test the method. The HIP-densified wood's microstructural, chemical, physical, and mechanical properties were assessed. Apart from the high densification values and volume preservation, the results indicate that proposed method was effective for all the tested species, showing homogenous density patterns, stable densification without noticeable shape recovery, and enhanced mechanical properties. Future research should test the HIP method in softwoods and consider the ring orientation in order to enhance the control of the densified geometry.

Características clínicas y microbiológicas de las infecciones de piel y tejidos blandos por Staphylococcus aureus en niños de un hospital en Medellín durante los años 2013 a 2015 / Clinical and microbiological characteristics of skin and soft tissue infections caused by Staphylococcus aureus in children in a hospital in Medellin from 2013 to 2015

Resumen Introducción: El principal microorganismo implicado en las infecciones de piel y tejidos blandos (IPTB) es Staphylococcus aureus, con incremento en las cepas resistentes a meticilina en los últimos años. Objetivo: Identificar la frecuencia de S. aureus resistente a meticilina (SARM) en IPTB en niños que consultaron a un hospital de cuarto nivel en la ciudad de Medellín. Métodos: Estudio descriptivo, retrospectivo, a partir de la revisión de historias clínicas. Se incluyeron pacientes menores de 18 años con IPTB causadas por S. aureus que no cumplieran con criterios de enfermedad invasora. Resultados: La prevalencia de SARM en esta población fue de 31%. El principal diagnóstico fue absceso cutáneo (68%), seguido por infección de sitio quirúrgico (15%) y celulitis no purulenta (6%). Tenían alguna co-morbilidad 85% de los pacientes. Todos los aislados fueron sensibles a rifampicina y cotrimoxazol. Ocho por ciento de los aislados fueron resistentes a clindamicina. Se encontró mayor prevalencia de SARM en lactantes comparado con los mayores de 2 años (60 vs 23%, p = 0,0109). Conclusión: Ante la alta prevalencia de SARM en IPTB se recomienda incluir en el tratamiento empírico antimicrobianos con cobertura para estas cepas, principalmente para lactantes.

Background: Skin and soft tissue infections (SSTI) are very common in children and Staphylococcus aureus is the main agent, with an increase of methicillin resistant strains (MRSA) in recent years. Aim: To identify the frequency of MRSA in skin and soft tissue infections (SSTI) in children from a high complex hospital in Medellin, Colombia. Methods: This is a descriptive, retrospective study, information was obtained from medical records. We included patients younger than 18 years with SSTI due to S. aureus who did not meet criteria for invasive disease. Results: The prevalence of MRSA in this population was 31%. The main diagnosis was cutaneous abscess (68%), followed by surgical site infection (15%) and non-purulent cellulitis (6%). Eighty five percent of the patients had at least 1 comorbidity. All isolates were sensitive to rifampicin and cotrimoxazole and 8% of the isolates were resistant to clindamycin. There was a higher prevalence of MRSA in patients under 2 years compared to older (60 vs 23%, p = 0,0109). Conclusion: In view of the high prevalence of MRSA in SSTI, empirical treatment with adequate coverage for MRSA is recommended, especially for patients under 2 years of age.

[Clinical and microbiological characteristics of skin and soft tissue infections caused by Staphylococcus aureus in children in a hospital in Medellin from 2013 to 2015]. / Características clínicas y microbiológicas de las infecciones de piel y tejidos blandos por Staphylococcus aureus en niños de un hospital en Medellín durante los años 2013 a 2015.

BACKGROUND: Skin and soft tissue infections (SSTI) are very common in children and Staphylococcus aureus is the main agent, with an increase of methicillin resistant strains (MRSA) in recent years. AIM: To identify the frequency of MRSA in skin and soft tissue infections (SSTI) in children from a high complex hospital in Medellin, Colombia. METHODS: This is a descriptive, retrospective study, information was obtained from medical records. We included patients younger than 18 years with SSTI due to S. aureus who did not meet criteria for invasive disease. RESULTS: The prevalence of MRSA in this population was 31%. The main diagnosis was cutaneous abscess (68%), followed by surgical site infection (15%) and non-purulent cellulitis (6%). Eighty five percent of the patients had at least 1 comorbidity. All isolates were sensitive to rifampicin and cotrimoxazole and 8% of the isolates were resistant to clindamycin. There was a higher prevalence of MRSA in patients under 2 years compared to older (60 vs 23%, p = 0,0109). CONCLUSION: In view of the high prevalence of MRSA in SSTI, empirical treatment with adequate coverage for MRSA is recommended, especially for patients under 2 years of age.

Caracterización de la restenosis de stents coronarios convencionales y liberadores de medicamentos en pacientes incluidos en el registro DRug Eluting STent (DREST) / Characterization of conventional coronary stents restenosis and drug eluting stents in patients included in the Drug Eluting Stent Registry (DREST)

Introducción y objetivos: los stents convencionales presentan tasas de restenosis intrastent entre 10% y 60%, mientras los stents liberadores de fármacos alcanzan el 10%. Para Latinoamérica, no hay reportes de restenosis intrastent en comparación con los stents convencionales y los stents liberadores de fármacos. En este estudio se describen aspectos asociados a este evento en pacientes atendidos en un centro de alta complejidad en Colombia. Métodos: análisis retrospectivo de pacientes con restenosis intrastent incluidos en el registro DRug ELuting STent (DREST) entre los años 1994 y 2011, en el que se compararon características basales, datos técnicos y supervivencia de los pacientes con stent convencional y stent liberador de fármacos. Resultados: se evidenció restenosis intrastent en 269 con stent convencional (11,5%) y en 65 con stent liberador de fármacos (12,2%), sin diferencias significativas al comparar por género (p=0,983) o edad (p=0,55). La dislipidemia fue el factor de riesgo más significativo asociado a la restenosis intrastent de los stents liberadores de fármacos (p<0,002). El diámetro menor del vaso comprometido como de los stents implantados, se encontró principalmente en los stents liberadores de fármacos asociados a restenosis intrastent (p=0,000). El patrón de restenosis intrastent focal fue mayor con los stents liberadores de fármacos, mientras el difuso en con el stent convencional (p=0,000). La supervivencia a un año fue mayor en pacientes con stent liberador de fármacos. Conclusiones: las tasas de restenosis intrastent y las características relacionadas encontradas, son similares a lo publicado. La dislipidemia aparece como factor asociado significativo. La restenosis intrastent se manifestó como síndrome coronario agudo en 60% de los casos; no puede considerarse como un proceso benigno en esta población.

Introduction and Objectives: Bare metal stents have stent restenosis rates between 10% and 60%, while drug-eluting stents reach 10%. In Latin America, there are no reports of stent restenosis between bare-metal stents and drug eluting stents. This study describes aspects associated with this event in patients treated at a center of high complexity in Colombia. Methods: Retrospective analysis of patients with stent restenosis included in the Drug Eluting Stent Registry (DREST) between 1994 and 2011, which compared baseline characteristics, technical data and survival of patients with bare metal stents and drug eluting stents. Results: We found stent restenosis with bare metal stents in 269 patients (11.5%) and in 65 with drug-eluting stent (12.2%) without significant differences between gender (p = 0.983) or age (p = 0 , 55). Dyslipidemia was the most significant risk factor associated with stent restenosis of drug-eluting stents (p <0.002). We found smaller diameter of the vessel involved as well as smaller diameter of the implanted stent mainly in the drug-eluting stents associated with stent restenosis (p = 0.000). The focal pattern of stent restenosis was higher with drug eluting stents, while the diffuse pattern with standard stents (p = 0.000). The one-year survival was higher in patients with drug-eluting stent. Conclusions: The rates of stent restenosis and the related characteristics found are similar to those currently published. Dyslipidemia appears as a significant associated factor. The stent restenosis manifested as acute coronary syndrome in 60% of cases; it can not be regarded as a benign condition in this population.

Intoxicación por sales de hierro en una embarazada / Iron salts overdose in a pregnant patient

La intoxicación por hierro puede causar un fracaso multiorgánico que puede llevar a la muerte y, en algunos países, constituye la segunda causa de fallecimiento en las embarazadas a consecuencia de una intoxicación. Se presenta el caso de una paciente de 27 años y treinta semanas de gestación, que ingirió con ánimo autolítico 30 mg/kg de sulfato de hierro. Tras unas manifestaciones iniciales de gastritis, se constató la presencia de comprimidos radioopacos en una radiografía simple de abdomen, por lo que dada la dosis ingerida, se aplicó un tratamiento descontaminante digestivo a base de polietilenglicol. La concentración de hierro en sangre fue normal, haciendo innecesaria la terapia antidótica con deferoxamina. Tras un período de observación, la paciente fue dada de alta asintomática. El resto del embarazo transcurrió normalmente y la paciente tuvo un parto a término, sin que se detectasen malformaciones en el recién nacido. Se revisa el mecanismo fisiopatológico, las manifestaciones clínicas y el tratamiento de la intoxicación por hierro, haciendo especial énfasis en las características de este tóxico en la embarazada

Iron intoxication may cause a multiorganic failure that may lead to death and, in some countries, it is the second cause of death in pregnants due to intoxication. We show the case of a 27years old patient, thirty weeks pregnant, who ingested 30 mg/kg of ferrous sulfate in a suicide attempt. She had some gastrointestinal symptoms such as gastritis. The presence of radioopaque pills was observed in an abdominal radiography. Therefore, a digestive descontamination treatment with polietilenglicol was initiated. The serum concentratrion of iron was normal, and for this reason, deferoxamine treatment was unecessary. After an observativon period, she was asymtomatic and she was discharged from the hospital. Her pregnancy was normal and she delivered a healthy child without malformations. We review the pathophysiology, clinical manifestations and treatment of iron intoxication with special emphasis on the pregnant patient

Corneal graft survival and intraocular pressure control after penetrating keratoplasty and glaucoma drainage device implantation.

OBJECTIVE: To investigate corneal graft survival rates and intraocular pressure (IOP) control in eyes after penetrating keratoplasty (PK) and glaucoma drainage device (GDD) implantation. DESIGN: Retrospective, comparative, consecutive case series. PARTICIPANTS: All patients who underwent PK and GDD implantation at the Bascom Palmer Eye Institute between January 1, 1993 and October 31, 1998. MAIN OUTCOME MEASURES: Graft clarity and IOP control. RESULTS: Of the 72 eyes in 72 patients identified, 47 (65%) underwent combined PK and GDD implantation, and 25 (35%) underwent GDD placement after PK (2-30 months after PK; median, 13 months). The GDD type was Baerveldt 350 mm(2) in 57 eyes, Ahmed in 9, Krupin in 2, and other in 4 eyes. The GDD was placed in the anterior chamber in 54 eyes (75%) and in the vitreous cavity in 18 eyes (25%). Preoperative IOP was 11 to 53 mmHg with or without antiglaucoma medications in 16 eyes (30%) with the GDD implanted in the anterior chamber and in 4 eyes (22%) with the GDD placed in the vitreous cavity (P = 0.76). At 1 year after GDD implantation, the graft was clear in 26 eyes (48%) with the GDD in the anterior chamber compared with 15 eyes (83%) with the GDD in the vitreous cavity (P = 0.013). Forty-eight eyes (89%) with the GDD in the anterior chamber and 18 eyes (100%) with the GDD in the vitreous cavity had IOP between 5 and 21 mmHg with or without antiglaucoma medications (P = 0.33). The mean reduction in IOP, 1 year after surgery, was 12 mmHg among eyes with the GDD in the anterior chamber, compared with 17 mmHg among eyes with the GDD in the vitreous cavity (P = 0.13) CONCLUSIONS: Corneal graft survival at 1 year is significantly higher among eyes with the GDD implanted in the vitreous cavity compared with those in which the GDD is implanted in the anterior chamber. The IOP was significantly lower at 1 year after surgery compared with before surgery in both groups, and there was no significant difference between the groups in IOP control and amount of IOP reduction. There was no significant difference in corneal graft survival or IOP control between eyes with the GDD implanted concurrently with the PK versus after the PK.

[Recurrent otitis media with effusion and food allergy in pediatric patients]. / Otitis media recurrente con efusión y alergia a los alimentos en pacientes pediátricos.

INTRODUCTION: Recurrent otitis media with effusion continues to be important pediatric clinical problem and is related to food allergy. OBJECTIVE: The purpose of the present investigation was to determine if the recurrent otitis media with effusion was associated to food allergy. METHODS: We reviewed medical charts from children with food allergy and otitis media with effusion for a period of three months of duration or every month for the last six months seen in an allergy clinic. Patients with anatomic abnormalities, polypous or immunologic deficiencies were excluded. Every patient was challenged with foods to which he/she was allergic in order to demonstrate cause-effect. In all patients we performed tympanometries. RESULTS: We found twenty five patients with recurrent otitis media with effusion and food allergy demonstrated by positive skin testing. The most common food found to be associated was milk, egg, beans, citrus, and tomato. The elimination of the food diet led to a significant amelioration of the otitis in 22 patients, in whom clinical and tympanometry evaluation was performed. The challenge diet with suspected offending food provoked a recurrence of the otitis problem. CONCLUSION: These results demonstrated the association between recurrent otitis media with effusion and food allergy. Therefore, all patients with recurrent otitis media with effusion should be investigated for food allergy.

[Klebsiella pneumoniae glycoproteins as coadjuvants in the prevention of recurrent respiratory infections in children 1-6 years of age]. / Glicoproteínas de Klebsiella pneumoniae como coadyuvantes en la prevención de infecciones recurrentes respiratorias en niños de 1 a 6 años de edad.

MATERIAL AND METHOD: Forty two children with clinical diagnosis of recurrent high and low respiratory infections, were treated with an extract of P1 and F1 glycoproteins; fraction of Klebsiella pneumoniae, 1 g/day for one week a month for three months, according to a double-blind, randomized, parallel group trial. RESULTS: Improvement of clinical and laboratory results were compared with 44 control patients with the same age and similar sex distribution, that were treated with placebo. At the end of study, clinical analysis at 6, 9 and 12 months after the initial dose of Klebsiella pneumoniae, decreased in the number of respiratory infections, sick days, and school assistance were observed in the study group when compared with the control group (p < 0.001 in all parameters). There were not statistical significant changes in hemolytic complement, C3, C4 and immunoglobulins (IgA, IgG, IgM and IgE) levels before and after treatment and between groups. There were not observed adverse reactions to oral treatment with this extract of Klebsiella pneumoniae. CONCLUSIONS: These results suggested that the extract of Klebsiella can be used as a coadjuvant in the treatment of pediatric patients with recurrent high and low respiratory infections.

[Myocardiopathy diagnosed in utero in a mother with SS-A antibodies treated with plasmapheresis]. / Miocardiopatía diagnosticada in utero en madre con anticuerpos contra SS-A tratada con plasmaféresis.

We report a 36 years old patient with Sjogren's syndrome, who during her second pregnancy, the product developed a miocardiopathy with complete heart block that was diagnosed in utero at 26 weeks of pregnancy. Simultaneously, laboratory data reported a SS-A/Ro titer of 1:50,000 with positive antiphospholipids antibodies. Patient was subjected three times to plasmapheresis with three blood volume exchange each time. During the procedures, we had monitor the product and no hemodinamic changes were observed. Unfortunately, 25 days later the patient reported absence of fetal movement and by ecosonography and Doppler was not observed fetal movement or cardiac function. This pregnancy ends in cesarea. The patient is in perfect clinical conditions under control using prednisone and methotrexate.

[Identification of antinuclear, nucleolar and SS-A antibodies, using an immunoassay system]. / Identificación de anticuerpos antinucleares, nucleolares y SS-A, con el uso de un sistema de inmunoensayo.

In this paper we report a solid phase ELISA for screening of antinuclear, nucleolar, and SS-A antibodies. The test system was evaluated with 158 sera that were positive by immunofluorescence (IF), some of which were immunologically characterized as containing antibodies to Sm, RNP, SS-A, SS-B, nucleolar, and DNA, and 247 IF negative that were used as a control group. Ninety eight per cent of serum samples with an antibody of known specificity and/or positive IF, were positive by the ELISA system including antinucleolar samples. Reproducibility of the assay was demonstrated by using five sequentially prepared antigenic extracts. The lineal regression from the last experiment was between 0.75 and 0.91. With this system, positive and negative ANA can be identified as the screening procedure without the need of additional studies. To our knowledge this is the first ELISA system report for the screening of antinucleolar antibodies.

[The rapid diagnosis of rubella and measles by the dot immunoassay method]. / Diagnóstico rápido de rubéola y sarampión por el método de inmunoensayo en mancha.

A procedure is described for the routine laboratory identification of IgM or/and IgG antibodies to measles and rubella simultaneously. A rapid dot-immunobinding assay on nitrocellulose was compared with ELISA systems. 58 serum samples from patients with an exanthematous disease and 15 serum negative samples for both virus were studied. The type of antibody found in all samples was variable and was always related to the presence of immunity in each individual. However, all known negative samples were negative. When results were compared with commercially available ELISA systems or reference laboratories, we found an excellent correlationship including titers. We concluded that the dot-immunobinding assay is a rapid, specific, sensitive, reproducible and economic test that can be used simultaneously for identification of several antigens.

The frequency of antinuclear antibody (ANA) in children by use of mouse kidney (MK) and human epithelial cells (HEp-2) as substrates.

The purpose of this study was to determine the frequency of antinuclear antibody (ANA) in a normal pediatric population. Sera from 241 children (age range 4 months to 16 years) were tested for IgG ANA by use of indirect immunofluorescence and two commercially available substrates, mouse kidney and human epithelial cells. Patients' sera were tested at three different dilutions. The positivity of the ANA was related to the substrate used. When a screening dilution of 1:5 or 1:10 was used, 2.0% and 1.6% were positive with the mouse kidney or human epithelial cell substrates, respectively, but the positivity dropped to 0.4% when the dilution was 1:20 and 1:40, respectively. Only one serum was positive with both substrates.

Cryoprecipitates in Kawasaki syndrome: association with coronary artery aneurysms.

Cryoprecipitates are postulated to play a role in the pathogenesis of several vasculitis illnesses and infectious diseases. To investigate the presence of cryoprecipitates in Kawasaki syndrome, we studied sera from 25 children with acute Kawasaki syndrome. None of the subjects was treated with intravenous gamma-globulin. Cryoprecipitates were detectable in sera of 11 of 25 (44%) children studied. The mean (+/- SE protein concentration of the cryoprecipitates was 88.0 (+/- 20.2) micrograms/ml serum. Cryoprecipitates consisted primarily of IgG and IgM; no complement components were detected but highly sensitive methods were not used. The presence of cryoprecipitates in the serum of children with acute Kawasaki syndrome was associated with the subsequent development of coronary artery aneurysms detected by echocardiogram (P less than 0.05). There was no association between detectable cryoprecipitates and either peak platelet count or erythrocyte sedimentation rate. In one patient, measurement of cryoprecipitates in serial samples showed a reduction in concentrations that paralleled subsidence of disease activity. We speculate that cryoprecipitates may be a marker for increased risk of coronary aneurysm formation and may play a role in the pathogenesis of the cardiac disease in Kawasaki syndrome.

Cobra venom factor, an activator of the complement system, enhances the bowel necrosis induced by platelet-activating factor.

We have previously produced an experimental model of ischemic bowel necrosis in the rat by injecting platelet activating factor (PAF) (7 micrograms/kg) into the mesenteric vascular bed. The dose of PAF required to produce necrosis could be reduced to 50% if the animal was pretreated with bacterial endotoxin (lipopolysaccharide) (20 micrograms/rat). The mechanism of this potentiating effect of lipopolysaccharide is unclear, but activation of the complement system may be one of the contributing factors. To investigate the role of the complement system, we injected cobra venom factor (CVF) (1 unit/kg) to activate the complement system before injection of PAF (2 micrograms/kg) into the superior mesenteric artery. CVF and PAF were also injected separately at the same dosage to other groups of rats. CVF activated the complement system, but by itself did not produce gross necrosis of the bowel. PAF alone caused 3 out of 9 rats treated to develop bowel necrosis. In contrast, combination of the two produced bowel necrosis in all 6 rats thus treated. CVF did not enhance the effects of PAF on hemoconcentration and leukopenia, but aggravated the hypotension caused by PAF. PAF, on the other hand, also enhanced activation of the complement system by CVF. To investigate the specificity of PAF on complement activation, lyso-PAF was used in combination with CVF. It was found that lyso-PAF did not have a significant potentiating effect on CVF-induced complement activation and, by itself, it had no effect on complement activation, blood pressure, white blood cell count or hematocrit. Lyso-PAF, with or without CVF, also failed to produce bowel necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Scleromyxedema with corneal deposits.

Scleromyxedema (Arndt-Gottron syndrome) is a rare cutaneous disease in which hyaluronic acid is deposited in the dermis. The authors describe a patient with scleromyxedema and corneal deposits. A corneal biopsy demonstrated hyaluronic acid deposition in the corneal stroma and amyloid P component in Bowman's membrane. This is the first report of scleromyxedema involving the cornea. It is also the first report of amyloid P component deposition in the cornea occurring independent of corneal amyloid deposits.

Activation of complement and coagulation in juvenile dermatomyositis.

In patients with juvenile dermatomyositis (JDM), small vessel occlusion and thrombosis result in a decrease in the capillary: muscle fiber ratio. We studied 15 patients with JDM. Six of 7 patients with clinically active JDM had elevated levels of C3d. Moreover, concentrations of fibrinopeptide A and factor VIII-related antigen were significantly increased in patients with clinically active JDM.

Levels of IgE in serum from normal children and allergic children as measured by an enzyme immunoassay.

Serum IgE levels of 346 nonallergic and 301 allergic children were measured by an enzyme immunoassay. The data are presented as the geometric mean +/- 95% confidence interval for each age from less than 1 to 12 years of age with those 13 to 16 years of age, pooled. The geometric mean for nonallergic patients increases from 0.9 IU/ml at less than 1 year of age to 45.4 IU/ml at 13 to 16 years of age. By use of an IgE value between confidence intervals of allergic and nonallergic subjects, a cutoff value for each age was established to differentiate allergic from nonallergic children. This value increases from 10 IU/ml at less than 1 year to 100 IU/ml at 13 to 16 years of age. The diagnostic sensitivity and specificity of the assay, based on the cutoff values, average 83% and 91%, respectively.