Pre-clinical evaluation of fretting-corrosion at stem-head and stem-cement interfaces of hip implants using in vitro and in silico models.

Prior to clinical use, the corrosion resistance of new prosthesis system must be verified. The fretting-corrosion mechanisms of total hip arthroplasty (THA) implants generate metal debris and ions that can increase the incidence of adverse tissue reactions. For cemented stems, there are at least two interfaces that can be damaged by fretting-corrosion: stem-head and stem-cement. This investigation aimed to evaluate, through in vitro and in silico analyses, fretting-corrosion at the stem-head and stem-cement interfaces, to determine which surface is most affected in pre-clinical testing and identify the causes associated with the observed behavior. Unimodular stems and femoral heads of three different groups were evaluated, defined according to the head/stem material as group I (SS/SS), group II (CoCr/SS), and group III (CoCr/CoCr). Seven pairs of stems and heads per group were tested: three pairs were subjected to material characterization, three pairs to in vitro fretting-corrosion testing, and one pair to geometric modeling in the in silico analysis. The absolute area of the stem body degraded was more than three times higher compared with the trunnion, for all groups. These results were corroborated by the in silico analysis results, which revealed that the average micromotion at the stem-cement interface (9.65-15.66 µm) was higher than that at the stem-head interface (0.55-1.08 µm). In conclusion, the degradation of the stem-cement interface is predominant in the pre-clinical set, indicating the need to consider the fretting-corrosion at the stem-cement interface during pre-clinical implant evaluations.

The HIV epidemic in Colombia: spatial and temporal trends analysis.

BACKGROUND: Colombia has the fourth highest incidence rate of HIV/AIDS among all Latin American countries and it has been increasing since the 1980s. However, the number of studies that addresses this trend is limited. Here, we employed spatial and temporal trend analyses to study the behaviour of the epidemic in the Colombian territory. METHODS: Our sample included 72,994 cases of HIV/AIDS and 21,898 AIDS-related deaths reported to the National Ministry of Health between 2008 and 2016. We employed the joinpoint regression model to analyse the annual HIV/AIDS incidence and AIDS mortality rates. In the spatial analysis, we used univariate autocorrelation techniques and the Kernel density estimator. RESULTS: While the HIV/AIDS incidence had an increasing trend in Colombia, the AIDS mortality rate was stable. HIV/AIDS incidence and AIDS mortality showed a downward trend in the 0-14 age group. An upward trend was observed for HIV/AIDS incidence in people older than 15 years and with the highest trend in the 65 years and above group. AIDS mortality showed an increasing trend among people aged 65 years or older. The comparison between the sexes showed an upward trend of HIV/AIDS incidence in all age groups and AIDS-mortality rates in 65 years and above in men, while in women, the incidence was upward among those aged 45 years and above, and concerning the AIDS-mortality rate in the 45-64 group. The high-high clusters of HIV/AIDS incidence and AIDS mortality were located in the Andean and Caribbean regions. CONCLUSION: Our study found an upward trend in HIV/AIDS incidence and a stable trend in the AIDS mortality rate in Colombia. The downward trend in HIV/AIDS incidence and AIDS mortality rate in the 0-14 age group reflects the downwards mother-to-child HIV transmission. The upward trend in HIV/AIDS incidence in older women and AIDS mortality in younger women rates, compared with men, may be due to late diagnosis and treatment. The Caribbean and the 'coffee belt' regions were the most impacted by the HIV epidemic, most likely due to sexual tourism. Our results provide crucial information that may help Colombian health authorities fight HIV transmission.

Open abdomen and entero-atmospheric fistulae: An interim analysis from the International Register of Open Abdomen (IROA).

INTRODUCTION: No definitive data describing associations between cases of Open Abdomen (OA) and Entero-atmospheric fistulae (EAF) exist. The World Society of Emergency Surgery (WSES) and the Panamerican Trauma Society (PTS) thus analyzed the International Register of Open Abdomen (IROA) to assess this question. MATERIAL AND METHODS: A prospective analysis of adult patients enrolled in the IROA. RESULTS: Among 649 adult patients with OA 58 (8.9%) developed EAF. Indications for OA were peritonitis (51.2%) and traumatic-injury (16.8%). The most frequently utilized temporary abdominal closure techniques were Commercial-NPWT (46.8%) and Bogotà-bag (21.9%). Mean OA days were 7.9 ± 18.22. Overall mortality rate was 29.7%, with EAF having no impact on mortality. Multivariate analysis associated cancer (p = 0.018), days of OA (p = 0.003) and time to provision-of-nutrition (p = 0.016) with EAF occurrence. CONCLUSION: Entero-atmospheric fistulas are influenced by the duration of open abdomen treatment and by the nutritional status of the patient. Peritonitis, intestinal anastomosis, negative pressure and oral or enteral nutrition were not risk factors for EAF during OA treatment.

Erratum to: IROA: International Register of Open Abdomen, preliminary results.

[This corrects the article DOI: 10.1186/s13017-017-0123-8.].

IROA: International Register of Open Abdomen, preliminary results.

BACKGROUND: No definitive data about open abdomen (OA) epidemiology and outcomes exist. The World Society of Emergency Surgery (WSES) and the Panamerican Trauma Society (PTS) promoted the International Register of Open Abdomen (IROA). METHODS: A prospective observational cohort study including patients with an OA treatment. Data were recorded on a web platform (Clinical Registers®) through a dedicated website: www.clinicalregisters.org. RESULTS: Four hundred two patients enrolled. Adult patients: 369 patients; Mean age: 57.39±18.37; 56% male; Mean BMI: 36±5.6. OA indication: Peritonitis (48.7%), Trauma (20.5%), Vascular Emergencies/Hemorrhage (9.4%), Ischemia (9.1%), Pancreatitis (4.2%),Post-operative abdominal-compartment-syndrome (3.9%), Others (4.2%). The most adopted Temporary-abdominal-closure systems were the commercial negative pressure ones (44.2%). During OA 38% of patients had complications; among them 10.5% had fistula. Definitive closure: 82.8%; Mortality during treatment: 17.2%. Mean duration of OA: 5.39(±4.83) days; Mean number of dressing changes: 0.88(±0.88). After-closure complications: (49.5%) and Mortality: (9%). No significant associations among TACT, indications, mortality, complications and fistula. A linear correlationexists between days of OA and complications (Pearson linear correlation = 0.326 p<0.0001) and with the fistula development (Pearson = 0.146 p= 0.016). Pediatric patients: 33 patients. Mean age: 5.91±(3.68) years; 60% male. Mortality: 3.4%; Complications: 44.8%; Fistula: 3.4%. Mean duration of OA: 3.22(±3.09) days. CONCLUSION: Temporary abdominal closure is reliable and safe. The different techniques account for different results according to the different indications. In peritonitis commercial negative pressure temporary closure seems to improve results. In trauma skin-closure and Bogotà-bag seem to improve results. TRIAL REGISTRATION: ClinicalTrials.gov NCT02382770.

Relação entre o escore TIMI e o tempo para realização da cinecoronariografia em pacientes com IAMSSST / Relation between the TIMI risk score of patients with nstemi and the TIME to start performing the coronary angiography

As doenças cardiovasculares, principal causa de morte em nosso país e na maioria dos países, resultam de diversos fatores de risco. O infarto agudo do miocárdio apresenta-se de duas maneiras: com supradesnivelamento do segmento ST (IAMCSST) e sem supradesnivelamento do segmento ST (IAMSSST). A abordagem terapêutica do IAMSSST baseia-se na estratificação de risco, podendo ser realizada através do escore TIMI. O objetivo desse estudo foi verificar os fatores de risco para doenças cardiovasculares e a relação entre o escore TIMI de pacientes com IAMSSST e o tempo para realização da cinecoronariografia. Estudo transversal, prospectivo com componente analítico, realizado no período de 01 de agosto de 2011 a 30 de novembro de 2011.O censo foi constituído de 97 pacientes com diagnóstico de IAMSSST. Verificou-se que a maioria dos pacientes era do sexo masculino (56,7%). A idade média dos pacientes foi de 63 anos, sendo a hipertensão arterial sistêmica o fator de risco mais frequente. O escore TIMI mais prevalente foi o intermediário, o tempo para realização da conduta invasiva foi o tardio e a terapêutica mais prevalente a angioplastia. Dentre o total de pacientes, 81,5% foram submetidos à cinecoronariografia, sendo que 37,9% foram submetidos precocemente e 62,1% tardiamente. A frequência de cinecoronariografia precoce foi 53% maior nos pacientes de alto risco quando comparados com os de baixo risco (p>0,05). Os principais fatores de risco para doenças cardiovasculares foram: hipertensão arterial sistêmica, dislipidemia, tabagismo, história familiar, diabetes e obesidade. Quanto maior o escore TIMI, mais precoce foi a realização da cinecoronariografia.

Cardiovascular diseases are the leading cause of deaths in our country, as well as in most countries, due to several risk factors. Acute myocardial infarction can occur in two ways: ST-segment elevation (STEMI) and non-ST-segment elevation (NSTEMI). The therapeutic approach of NSTEMI based on risk-stratification can use the TIMI risk score. The objectives were to verify the risk factors for cardiovascular diseases, and the relation between the TIMI risk score of patients with NSTEMI and the time to start performing the coronary angiography. Cross-sectional, prospective analytical study made from august 01st 2011 to November 30th 2011.The census was carried out in 97 patients diagnosed with NSTEMI. It was found that most patients were men (56,7%). The average age of these patients was 63 years old, and systemic arterial hypertension was the most common risk factor. The most prevalent TIMI risk score was intermediate, delayed invasive intervention was performed and the most common therapy was angioplasty. Among the 97 patients, 81,5% were submitted to coronary angiography, from this total, 37,9% to early invasive intervention and 62,1% to delayed invasive intervention. The frequency of early coronary angiography was 53% superior in high-risk patients when compared to those of low-risk (p>0,05).The main risk factors for cardiovascular diseases were: systemic arterial hypertension, dyslipidemia, smoking, family history, diabetes and obesity. The higher the TIMI risk score, the earlier coronary angiography was performed.