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Percutaneous biopsies (PBs) are the gold standard diagnostic procedures indicated for renal and hepatic disorders. Nevertheless, they can cause hemorrhages and are contraindicated for coagulopathic patients. In this study we designed, fabricated, and evaluated a small intestinal submucosa (SIS) plug to reduce, and potentially cease, bleeding to decrease death risk after percutaneous hepatic and renal biopsies in healthy and coagulopathic in vivo models. First, the plug's blocking capacity was determined with an increase in its diameter of 24 ± 11% after immersion in human blood, and the capacity to induce clotting on its surface. The plug's in vivo performance was evaluated in a healthy porcine model, which showed minimal inflammatory reaction without side effects confirmed by histological results after 30 days. The plug's response in the coagulopathic model was assessed using heparinized swine for 2 days, which revealed localized microhemorrhages and mild inflammatory response without any lesions to the surrounding tissue. No major adverse events nor macroscopic hemorrhages were detected in the animal models. Furthermore, we assessed the plug's efficacy to reduce and stop bleeding using a transplant-discarded human liver model (n = 14). In this case, the mass of blood lost was 43.8 ± 21.8% lower in plugged transplant-discarded human liver biopsies compared to control biopsies without a plug. The bleeding was stopped within three minutes in 92% of plugged cases, but only in 8% of non-plugged cases. We demonstrated the feasibility of making a hemostatic SIS plug, which does not induce major inflammatory reaction and can effectively reduce and stop bleeding after PBs in non-coagulopathic and coagulopathic in vivo models, and in a transplant-discarded human liver model. STATEMENT OF SIGNIFICANCE: Percutaneous biopsy (PB) is a gold standard diagnostic procedure, but it can provoke life-threatening complications and is contraindicated for patients with coagulopathic disorders. This study demonstrates that small intestinal submucosa (SIS) can be manufactured into a biocompatible thrombogenic plug, insertable through a commercial Tru-Cut needle sheath. This device takes advantage of the collagen-rich composition of SIS to stop and reduce bleeding more effectively than the traditional PB, indicating that it could be routinely employed in a traditional biopsy to increase safety, or as a cost and time-reducing alternative to transjugular biopsy for coagulopathic patients.

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OBJECTIVE: To estimate the age-specific incidence of symptomatic dengue and chikungunya in Colombia. METHOD: A passive facility-based fever surveillance study was conducted among individuals with undifferentiated fever. Confirmatory diagnostics included serological and molecular tests in paired samples, and surveillance's underreporting was assessed using capture-recapture methods. RESULTS: Of 839 febrile participants 686 completed the study. There were 33.2% (295/839) dengue infections (51% primary infections), and 35.9% (191/532) of negative dengue cases there were chikungunya cases. On average, dengue cases were younger (median = 18 years) than chikungunya cases (median = 25 years). Thrombocytopaenia and abdominal pain were the main dengue predictors, while presence of rash was the main predictor for chikungunya diagnosis. Underreporting of dengue was 31%; the estimated expansion factors indicate an underreporting rate of dengue cases of threefold for all cases and of almost sixfold for inpatients. CONCLUSIONS: These findings highlight the ongoing coexistence of both arboviruses, a distinct clinical profile of each condition in the study area that could be used by clinicians to generate a differential diagnosis, and the presence of underreporting, mostly among hospitalised cases.

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In small intestinal submucosa (SIS) scaffolds for functional tissue engineering, the impact of scaffold fabrication parameters on cellular response and tissue regeneration may relate to the mechanotransductory properties of the final arrangement of collagen fibres. We previously proved that two fabrication parameters, (a) preservation (P) or removal (R) of a dense collagen layer present in SIS, and (b) SIS in a final dehydrated (D) or hydrated (H) state, have an effect on the micromechanical environment of SIS. In a continuation of our studies, we herein hypothesized that these fabrication parameters also modulate early mechanotransduction in cells populating the scaffold. Mechanotransduction was investigated by seeding human umbilical vein endothelial cells (HUVECs) on scaffolds, exposing them to pulsatile shear stress (12 ± 4 dyne/cm2 ) for 1 h (n = 5) in a cone-and-plate shear system, and evaluating the expression of the mechanosensitive genes Pecam1 and Enos by immunofluorescence and qPCR. Expression of mechanosensitive genes was highest in PD grafts, followed by PH and RH grafts. The RD group had similar expression to that of unsheared control cells, suggesting that the RD combination potentially reduced mechanotransduction of shear to cells. We concluded that the two fabrication parameters studied, which modify SIS micromechanics, also potentially modulated the early shear-induced expression of mechanosensitive genes in seeded HUVECs. Our findings suggest that fabrication parameters influence the outcome of SIS as a therapeutic scaffold. Copyright © 2015 John Wiley & Sons, Ltd.

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Coculture assays allow the investigation of the role of endothelial cell and mural cell interactions in small vessel development and function. Different setups for coculture can be used to assay questions of interest. We include here methods for direct coculture, indirect coculture, and coculture in a three-dimensional extracellular matrix scaffold for studies of either a simple and direct association between the two cell types, the exchange of soluble molecules, or the interaction within a biomimetic tissue microenvironment.

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Small intestinal submucosa grafts for vascular regeneration have produced variable patency (0-100%) that has been concurrent with variability in fabrication techniques. We hypothesized that 1) preservation (P) or removal (R) of the stratum compactum layer of the intestine and 2) a dehydrated (D) or hydrated (H) state of the graft, affect early patency and tissue regeneration. We combined both parameters through a 2(2) factorial experimental design into four groups (PD, RD, PH, RH), and compared them in an in vivo early response predictive model (swine, ID 4.5 mm, 7d, n = 4). Patency, thrombogenicity, vascularization, fibroblast infiltration, macrophage polarization profile, endothelialization, and biaxial mechanics were assessed. PD grafts remained patent (4/4) but had scarce vascularization and fibroblast infiltration. RD and RH had extensive vascularization and fibroblast infiltration, however, RD had sustained patency (4/4) and the highest number of regeneration-associated phenotype macrophages (M2), whereas RH had lower patency (3/4) and less M2 macrophages. PH had a modest cellular infiltration, but the lowest patency (2/4) and a dominant adverse macrophage phenotype. Elasticity of R grafts evolved toward that of native carotids (particularly RD), while P grafts kept their initial stiffness. We concluded that fabrication parameters drastically affected early patency and regeneration, with RD providing the best results.

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In small intestinal submucosa scaffolds for functional tissue engineering, the impact of scaffold fabrication parameters on success rate may be related to the mechanotransductory properties of the final microstructural organization of collagen fibers. We hypothesized that two fabrication parameters, 1) preservation (P) or removal (R) of a dense collagen layer present in SIS and 2) SIS in a final dehydrated (D) or hydrated (H) state, have an effect on scaffold void area, microstructural anisotropy (fiber alignment) and mechanical anisotropy (global mechanical compliance). We further integrated our experimental measurements in a constitutive model to explore final effects on the micromechanical environment inside the scaffold volume. Our results indicated that PH scaffolds might exhibit recurrent and large force fluctuations between layers (up to 195 pN), while fluctuations in RH scaffolds might be larger (up to 256 pN) but not as recurrent. In contrast, both PD and RD groups were estimated to produce scarcer and smaller fluctuations (not larger than 50 pN). We concluded that the hydration parameter strongly affects the micromechanics of SIS and that an adequate choice of fabrication parameters, assisted by the herein developed method, might leverage the use of SIS for functional tissue engineering applications, where forces at the cellular level are of concern in the guidance of new tissue formation.

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BACKGROUND: Nail lichen planus affects 10% of all patients with lichen planus. It is a severe disease that may lead to destruction of the nail plate. It affects fingernails more than toenails. Early diagnosis is important due to its aggressive behavior. Histopathology should be carried out, but in many occasions it is not enough to come to a conclusive diagnosis. Dermatoscopy, a complementary tool, has proven to be useful in its diagnosis, management, and prognosis. Currently, there is very little data regarding dermatoscopy of nail lichen planus. METHODS: Dermatoscopic photographic data of 11 patients having 79 nails affected with nail lichen planus, seen in a specialized nail disease facility, were selected and analyzed. The data was confirmed with histopathological analysis. RESULTS: Dermatoscopy showed abnormalities of the nail matrix, with trachyonychia in 40.51% and pitting in 34.18%. As to nail bed anomalies, there was chromonychia in 55.70%, fragmentation of body of nail in 50.63%, splinter hemorrhage in 35.44%, onycholysis in 27.85%, and subungual keratosis in 7.59%. Concerning anomalies that involved nail matrix, bed, and perionychial region altogether, there were longitudinal streaks in 82.28% and anonychia in 1.27%. Paronychia was present in 31.65% of the cases. CONCLUSION: Considering that nail lichen planus is an underdiagnosed disease with severe consequences, early diagnosis is essential. This descriptive study of dermatoscopic characteristics of nail lichen planus would highlight some key changes in the course of the disease that will contribute to early diagnostic suspicion, early treatment, and could improve prognosis.

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Introduction: Up to 40 weeks of postconceptional age, the kangaroo mother program at the Hospital Universitario del Valle has proved to be a safe alternative for premature babies’ management with a low birth weight. Objectives: To evaluate the physical growth and morbidity in children followed since 40 weeks up to 1 year in the program. Material and methods: A cohort study was performed in newborn infants admitted to the kangaroo mother program in the newborn unit at the Hospital Universitario del Valle, Cali, Colombia, with birth weight lower than 2000 g, from 40 weeks postconceptional age up to one year age, between August 2002 and July 2006. Information was collected about maternal age and morbidity, prenatal control, type of birth, gender, birth weight, gestational age, breastfeeding, thick motor development, physical growth, morbidity, readmissions, mortality and tests results.Results: A total of 390 infants were admitted to the program, with a 61% of captation. 65% of theirs mothers did not have prenatal control. Before completing the 40 weeks, 5.3% were readmitted due to anaemia and apnoea. After 40 weeks, 13% were readmitted by bronchopneumonia and acute diarrhoea. Most of them were allocated in the reference percentiles for weight and size. Size had a better growth than weight. The cumulated low weight incidence for age at 13 months was 22%. Conclusions: To increase the coverage of prenatal control program and to watch that the children receive prescribed iron and formulated folic acid.

Introducción: Hasta las 40 semanas de edad postconcepcional, el programa madre canguro del Hospital Universitario del Valle, ha mostrado ser una alternativa segura para el manejo del prematuro con bajo peso al nacer. Objetivos: Evaluar el crecimiento pondoestatural y la morbilidad en los niños seguidos desde las 40 semanas de edad postconcepcional hasta el año en el programa. Materiales y métodos: Se evaluó la cohorte de niños que ingresaron al programa madre canguro en la unidad de recién nacidos del Hospital Universitario del Valle, Cali, Colombia, con peso <2,000 g, desde las 40 semanas de edad post-concepcional hasta el año de edad, entre agosto de 2002 y julio de 2006. Se recogieron datos sobre edad y morbilidad materna, control prenatal, vía de nacimiento, género, peso al nacer, edad gestacional, lactancia materna, desarrollo motor grueso, crecimiento físico, morbilidad, reingresos, mortalidad y resultado de pruebas. Resultados: Ingresaron 390 lactantes al programa con una captación de 61%. En 65% de sus madres no hubo control prenatal. Antes de completar las 40 semanas, 5.3% se hospitalizaron por anemia y apneas; después de las 40 semanas, 13% por bronconeumonía y diarrea aguda. La gran mayoría se ubicó dentro de los percentiles de referencia para peso y talla. La talla tuvo un mejor crecimiento que el peso. La incidencia acumulada de peso bajo para la edad a los 13 meses fue 22%. Conclusiones: Aumentar la cobertura del programa de control prenatal y vigilar que los niños reciban el hierro y el ácido fólico formulados.

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Introducción: El bajo peso al nacer es un problema de salud pública en los países en vía de desarrollo, que en América Latina produce una mortalidad neonatal 35 veces mayor a la esperada. En la unidad de recién nacidos del Hospital Universitario del Valle, 75% de los neonatos tienen <2,500 g. Objetivos: Evaluar los niños seguidos desde la unidad neonatal hasta las 40 semanas de edad gestacional en el programa madre canguro. Materiales y métodos: Se evaluó la cohorte de recién nacidos que ingresaron al programa madre canguro en la unidad de recién nacidos del Hospital Universitario del Valle, Cali, Colombia, con peso <2,001 g, que habían superado los principales problemas de adaptación neonatal y que contaran con una familia dispuesta a colaborar. Se excluyeron aquellos neonatos con malformaciones mayores o letales tempranas como encefalopatía hipóxica isquémica, hipertensión pulmonar, hemorragia intraventricular grado III y IV, y niños abandonados o a los que estaban en adopción. Se recogieron datos sobre crecimiento físico, duración de la lactancia materna, morbilidad, mortalidad, reingresos, fármacos, estancia y giro cama desde el egreso hasta las 40 semanas de edad gestacional. Resultados: Un total de 66 niños alcanzaron el término, 40 (60.6%) niñas, y 26 (39.4%) niños, con promedios (los rangos se dan entre paréntesis) de los siguientes datos al nacer: 32 semanas (27-38), edad gestacional; 1,434 g (700-1,950), peso; 41 cm (35-47), talla; y 28 cm (22-41), perímetro cefálico, respectivamente. Al egreso los datos correspondientes fueron: 34 semanas (31-39) edad gestacional; 19 días (4-48) edad postconcepción; y 1552 g (1,359-2,239), peso.

Introduction: Low birth weight is a health problem in non-developed countries, with a neonatal mortality rate 35 times higher in Latin America than the expected one. At the neonatal care unit of the University Hospital in Cali, Colombia, 75% of all live newborn infants are <2,500 g. Objectives: To evaluate the infants who were followed up until 40 weeks of postconceptional age in the kangaroo mother program. Methodology: A cohort study was performed in newborns infants <2,001 g who were admitted to the neonatal unit of the Hospital Universitario del Valle, Cali, Colombia, if they had overcome all major adaption problems to extrauterine life and had a family willing to follow the instructions. Exclusion criteria were lethal or major malformations, early detected major conditions arising from perinatal problem (severe hypoxic-ischaemic encephalopaty, pulmonary hypertension and intracerebral hemorrage III or IV), and either abandoned children or those who were given for adoption. All patients were monitored in physical growth, length of breast-feeding, morbility, mortality, readmissions, hospital stay and bed turn. Measurement were made at discharge, at 40 weeks of postconceptional age. Results: A total of 66 infants reached term, 40 (61%) were girls and 26 (39%) were boys, with a mean birth gestational age of 32 weeks (27-38) and mean birth weight of 1,434 g (700-1,950). Infants were discharged with mean gestational age of 34 weeks (31-39), mean postconceptional age of 19 day (4-48) and mean weight of 1,552 g (1,359-2,239).

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