A fully passive nonlinear piezoelectric vibration absorber.

The objective of this study is to develop the first fully passive nonlinear piezoelectric tuned vibration absorber (NPTVA). The NPTVA is designed to mitigate a specific resonance of a nonlinear host structure. To avoid the use of synthetic inductors which require external power, closed magnetic circuits in ferrite material realize the large inductance values required by vibration mitigation at low frequencies. The saturation of an additional passive inductor is then exploited to build the nonlinearity in the NPTVA. The performance of the proposed device is demonstrated both numerically and experimentally.This article is part of the theme issue 'Nonlinear energy transfer in dynamical and acoustical systems'.

A logistic regression model predicting high axillary tumour burden in early breast cancer patients

Purpose. As elective axillary dissection is loosing ground for early breast cancer (BC) patients both in terms of prognostic and therapeutic power, there is a growing interest in predicting patients with (nodal) high tumour burden (HTB), especially after a positive sentinel node biopsy (SNB) because they would really benefit from further axillary intervention either by complete lymph-node dissection or axillary radiation therapy. Methods/patients. Based on an analysis of 1254 BC patients in whom complete axillary clearance was performed, we devised a logistic regression (LR) model to predict those with HTB, as defined by the presence of three or more involved nodes with macrometastasis. This was accomplished through prior selection of every variable associated with HTB at univariate analysis. Results. Only those variables shown as significant at the multivariate analysis were finally considered, namely tumour size, lymphovascular invasion and histological grade. A probability table was then built to calculate the chances of HTB from a cross-correlation of those three variables. As a suggestion, if we were to follow the rationale previously used in the micrometastasis trials, a threshold of about 10% risk of HTB could be considered under which no further axillary treatment is warranted. Conclusions. Our LR model with its probability table can be used to define a subgroup of early BC patients suitable for axillary conservative procedures, either sparing completion lymph-node dissection or even SNB altogether (AU)

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A logistic regression model predicting high axillary tumour burden in early breast cancer patients.

PURPOSE: As elective axillary dissection is loosing ground for early breast cancer (BC) patients both in terms of prognostic and therapeutic power, there is a growing interest in predicting patients with (nodal) high tumour burden (HTB), especially after a positive sentinel node biopsy (SNB) because they would really benefit from further axillary intervention either by complete lymph-node dissection or axillary radiation therapy. METHODS/PATIENTS: Based on an analysis of 1254 BC patients in whom complete axillary clearance was performed, we devised a logistic regression (LR) model to predict those with HTB, as defined by the presence of three or more involved nodes with macrometastasis. This was accomplished through prior selection of every variable associated with HTB at univariate analysis. RESULTS: Only those variables shown as significant at the multivariate analysis were finally considered, namely tumour size, lymphovascular invasion and histological grade. A probability table was then built to calculate the chances of HTB from a cross-correlation of those three variables. As a suggestion, if we were to follow the rationale previously used in the micrometastasis trials, a threshold of about 10% risk of HTB could be considered under which no further axillary treatment is warranted. CONCLUSIONS: Our LR model with its probability table can be used to define a subgroup of early BC patients suitable for axillary conservative procedures, either sparing completion lymph-node dissection or even SNB altogether.

Role of axillary ultrasound, magnetic resonance imaging, and ultrasound-guided fine-needle aspiration biopsy in the preoperative triage of breast cancer patients

Purpose. Roughly two-thirds of early breast cancer cases are associated with negative axillary nodes and do not benefit from axillary surgery at all. Accordingly, there is an ongoing search for non-surgical staging procedures to avoid lymph-node dissection or sentinel node biopsy (SNB). Non-invasive imaging techniques with very high sensitivity (Se) and negative predictive value (NPV) could eventually replace SNB. We aimed to establish the role of axillary US and MRI, alone or in combination, associated with ultrasound-guided fine-needle aspiration biopsy (US-FNAB) in the prediction of axillary node involvement. Methods/patients. Between January 2003 and September 2015, we included 1505 of the 1538 breast cancer patients attending our centres. All patients had been referred from a single geographical area. Axillary US, magnetic resonance imaging and ultrasound-guided fine-needle aspiration biopsy (US-FNAB) were performed if required. Results. 1533 axillary US examinations and 1351 axillary MRI studies were analyzed. For axillary US, Se, Specificity (Sp), Positive Predictive Value (PPV), and NPV were 47.5, 93.6, 82.5, and 73.8%, respectively. For axillary MRI, corresponding values were 29.8, 96.6, 84.9, and 68.4%. When both tests were combined, Sp and PPV slightly improved over individual tests alone. US-FNAB showed a 100% Sp and PPV, with a Se of 80%. Conclusion. We may confidently state that axillary US and US-FNAB have to be included in the preoperative work-up of breast cancer patients (AU)

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Effectiveness of elective cervical cerclage according to obstetric history.

OBJECTIVE: To assess the effectiveness of elective history-indicated cervical cerclage according to obstetrical history. STUDY DESIGN: We analyzed pregnancy outcome of a retrospective cohort of women who have had history-indicated McDonald's cerclage. Principal outcome was gestational age (GA) at delivery. RESULT: Between January 2003 and December 2013, 205 women were included. We analyzed population in two risk groups: 1- Low-risk (≤2 prior preterm birth (PTB)/second trimester loss (STL), or prior success of cerclage), 2- High risk (≥3 prior PTB/STL, or prior failure of cerclage). In the high-risk group, there was a higher frequency of deliveries before 37 weeks (47.5% vs. 24.5%, P=0.001, OR=2.79, 95% CI [1.49-5.23]). Fifty percent of women (n=6/12) delivered before 37 weeks in case of three or more prior PTB/STL, and 51% (n=24/47) in case of prior failure of cervical cerclage. CONCLUSION: Elective cervical cerclage may be indicated for women with≤2 prior PTB/STL, or prior successful cerclage. For women with≥3 prior PTB/STL, trachelorraphy or cervico-isthmic cerclage could be possible alternatives to cervical cerclage.

Role of axillary ultrasound, magnetic resonance imaging, and ultrasound-guided fine-needle aspiration biopsy in the preoperative triage of breast cancer patients.

PURPOSE: Roughly two-thirds of early breast cancer cases are associated with negative axillary nodes and do not benefit from axillary surgery at all. Accordingly, there is an ongoing search for non-surgical staging procedures to avoid lymph-node dissection or sentinel node biopsy (SNB). Non-invasive imaging techniques with very high sensitivity (Se) and negative predictive value (NPV) could eventually replace SNB. We aimed to establish the role of axillary US and MRI, alone or in combination, associated with ultrasound-guided fine-needle aspiration biopsy (US-FNAB) in the prediction of axillary node involvement. METHODS/PATIENTS: Between January 2003 and September 2015, we included 1505 of the 1538 breast cancer patients attending our centres. All patients had been referred from a single geographical area. Axillary US, magnetic resonance imaging and ultrasound-guided fine-needle aspiration biopsy (US-FNAB) were performed if required. RESULTS: 1533 axillary US examinations and 1351 axillary MRI studies were analyzed. For axillary US, Se, Specificity (Sp), Positive Predictive Value (PPV), and NPV were 47.5, 93.6, 82.5, and 73.8%, respectively. For axillary MRI, corresponding values were 29.8, 96.6, 84.9, and 68.4%. When both tests were combined, Sp and PPV slightly improved over individual tests alone. US-FNAB showed a 100% Sp and PPV, with a Se of 80%. CONCLUSION: We may confidently state that axillary US and US-FNAB have to be included in the preoperative work-up of breast cancer patients.

The appropriate axillary procedure after a positive sentinel node in breast cancer patients: the 'Hôpital Tenon' score revisited. A two-institution study

Introduction. Until recently, completion ALND has been considered the standard of care after a positive SN in breast cancer patients. However, most patients will not display further axillary involvement. The Tenon score is a simple nomogram that can be used intraoperatively to avoid completion ALND in low-risk patients. We aimed at validating the Tenon score on a SN-positive patient sample that had been preoperatively selected using axillary US examination. Patients and method. We used a retrospective analysis of our bicentric database that included 246 breast cancer patients with a positive SN. We calculated sensitivity, specificity, as well as positive and negative predictive values for each cut-off point. ROCs were constructed and corresponding AUC values were calculated as a measure of discriminative capacity. Results. At least one non-SN was positive in 52 patients (21.1 %). 118 patients (48 %) had a score up to 5. Among them, three had at least one positive non-SN. NPV was 97.5 %. Using that threshold, the ROCs analysis showed an AUC of 0.822 (95 % CI 0.764-0.880). Conclusion. Use of preoperative axillary US examination led to a modification of the proposed Tenon cut-off value from 3.5 to 5 to attain good predictive power for non-SN status. Straightforward intraoperative use of the Tenon score may be considered an advantage over other available nomograms (AU)

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The appropriate axillary procedure after a positive sentinel node in breast cancer patients: the "Hôpital Tenon" score revisited. A two-institution study.

INTRODUCTION: Until recently, completion ALND has been considered the standard of care after a positive SN in breast cancer patients. However, most patients will not display further axillary involvement. The Tenon score is a simple nomogram that can be used intraoperatively to avoid completion ALND in low-risk patients. We aimed at validating the Tenon score on a SN-positive patient sample that had been preoperatively selected using axillary US examination. PATIENTS AND METHOD: We used a retrospective analysis of our bicentric database that included 246 breast cancer patients with a positive SN. We calculated sensitivity, specificity, as well as positive and negative predictive values for each cut-off point. ROCs were constructed and corresponding AUC values were calculated as a measure of discriminative capacity. RESULTS: At least one non-SN was positive in 52 patients (21.1 %). 118 patients (48 %) had a score up to 5. Among them, three had at least one positive non-SN. NPV was 97.5 %. Using that threshold, the ROCs analysis showed an AUC of 0.822 (95 % CI 0.764-0.880). CONCLUSION: Use of preoperative axillary US examination led to a modification of the proposed Tenon cut-off value from 3.5 to 5 to attain good predictive power for non-SN status. Straightforward intraoperative use of the Tenon score may be considered an advantage over other available nomograms.

Can we predict local recurrence in breast conserving surgery after neoadjuvant chemotherapy?

BACKGROUND: One of the benefits of neoadjuvant chemotherapy (NAC) is its ability to convert patients ineligible for breast conservative treatment (BCT) to be candidates for this treatment, although questions have been raised regarding the effectiveness of BCT in terms of loco-regional recurrence (LRR). The objective of this study is to evaluate LRR in this group and the influence of tumor characteristics in recurrence. MATERIAL AND METHODS: Between 1996 and 2007, 137 patients were treated with BCT after NAC at our Service. After completion of NAC a multidisciplinary team evaluated the cases eligible for BCT. All patients treated with BCT had negative margins and received radiation therapy. Risk factors associated with local recurrence were analyzed using Kaplan-Meier survival curves and long-rang test. RESULTS: Information was obtained in 121 patients. Median age was 54 years old (SD: 12 years). At a median follow-up of 35 months (range, 18-87 months), 6 (4.95%) patients developed an LRR, with an accumulative incidence at 5 years of 7.3% (95% CI: 0.4-14.1%) and at 10 years of 11.5% (95% CI: 2.8-20.1%). Overall survival at 5 and 10 years was 94.8% (95% CI: 90.9-98.6%) and 82.3% (95% CI: 67.3-97.2%) respectively. Tumor size (T3) (p < 0.001) and pathological stage (Stage III) (p = 0.001) after surgery were strongly associated with LRR. CONCLUSIONS: The results of this study confirm that BCT is an effective treatment in patients with NAC. Tumor size and pathological stage after systemic treatment influence loco-regional recurrence in patients with BCT.

Efectos de la contaminación atmosférica en el asma infantil / No disponible

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Correlation between increased platelet-associated IgG and thrombocytopenia in secondary dengue virus infections.

Although the public health impact of dengue is increasing rapidly, the mechanism of thrombocytopenia in this disease remains unknown. To elucidate this mechanism, the relationship between platelet-associated IgG (PAIgG) and platelet count in 53 patients in the acute phase of secondary dengue virus infection was investigated in a prospective-hospital-based study. A significant inverse correlation between the two parameters was found in these patients, while no correlation was observed in healthy volunteers. The low baseline platelet counts during the acute phase in 12 patients with secondary dengue virus infection significantly increased during the convalescent phase, while the increased PAIgG levels during the acute phase in these patients significantly decreased during the convalescent phase. Anti-platelet IgG autoantibody was detected rarely in the plasma of 53 patients with secondary dengue infection. The involvement of anti-dengue virus IgG was also shown in platelets from all of 8 patients in the acute phase of secondary dengue virus infection. These findings suggest that PAIgG formation involving anti-dengue virus IgG plays a pivotal role in the induction of transient thrombocytopenia during the acute phase of secondary dengue virus infection.

Development of the arterial pattern in the upper limb of staged human embryos: normal development and anatomic variations.

A total of 112 human embryos (224 upper limbs) between stages 12 and 23 of development were examined. It was observed that formation of the arterial system in the upper limb takes place as a dual process. An initial capillary plexus appears from the dorsal aorta during stage 12 and develops at the same rate as the limb. At stage 13, the capillary plexus begins a maturation process involving the enlargement and differentiation of selected parts. This remodelling process starts in the aorta and continues in a proximal to distal sequence. By stage 15 the differentiation has reached the subclavian and axillary arteries, by stage 17 it has reached the brachial artery as far as the elbow, by stage 18 it has reached the forearm arteries except for the distal part of the radial, and finally by stage 21 the whole arterial pattern is present in its definitive morphology. This differentiation process parallels the development of the skeletal system chronologically. A number of arterial variations were observed, and classified as follows: superficial brachial (7.7%), accessory brachial (0.6%). brachioradial (14%), superficial brachioulnar (4.7%), superficial brachioulnoradial (0.7%), palmar pattern of the median (18.7%) and superficial brachiomedian (0.7%) arteries. They were observed in embryos belonging to stages 17-23 and were not related to a specific stage of development. Statistical comparison with the rates of variations reported in adults did not show significant differences. It is suggested that the variations arise through the persistence, enlargement and differentiation of parts of the initial network which would normally remain as capillaries or even regress.

Truncal vagotomy and pyloroplasty for non-complicated duodenal ulcer: results 22-26 years after surgery.

OBJECTIVE: To assess the long-term results of truncal vagotomy and pyloroplasty in patients with non-complicated duodenal ulcer. PATIENTS AND METHODS: Between 1969 and 1973, 210 patients underwent surgery for non-complicated duodenal ulcer. Of these, 92 were followed up for 22-26 years. In 67 the assessment was conducted at the outpatient consultation and in 25, by phone. RESULTS: In 57% of patients the results were good or very good. Postpandrial fullness, heartburn and diarrhea were reported by 59, 52 and 42% of patients, respectively. Ulcerative recurrence affected 18% of patients. Although the relapsing rate was smaller in women as compared to men (7% versus 20%), physical condition and quality of life after surgery in the latter group were much worse. Thirty-five patients (38%) underwent reoperation. The distribution of patients according to the modified Visick classification after all the reoperations was as follows: I = 22 patients; II = 30 patients; III = 23 patients and IV = 17 patients. CONCLUSION: Long-term results after surgery for duodenal ulcer were not very encouraging, so we suggest for these patients a medical treatment and just in exceptional cases of refractory ulcers we would recommend a surgical procedure with minimal long-term complications.

Vagotomía troncular y piloroplastia en el tratamiento de la úlcera duodenal no complicada: resultados a los 22-26 años de la cirugía / Truncal vagotomy and pyloroplasty for non-complica ted duodenal ulcer: results at 22-26 years after surgery

Objetivo: valorar los resultados a largo plazo (22-26 años) de la vagotomía troncular y piloroplastia en el tratamiento electivo de la úlcera duodenal no complicada. Pacientes y métodos: entre los años 1969-1973, se intervinieron quirúrgicamente 210 pacientes por úlcera duodenal no complicada, de los cuales en 92 pudo realizarse una valoración de resultados a largo plazo. En 67 la valoración se realizó en consultas externas y en 25 por teléfono. Resultados: en el 57 por ciento de los pacientes los resultados fueron buenos o muy buenos. La pesadez postprandial, la pirosis y la diarrea fueron síntomas que afectaron respectivamente al 59, 52 y 42 por ciento de los pacientes. La recidiva ulcerosa fue del 18 por ciento. A pesar de que la recidiva en las mujeres fue inferior a la de los hombres (7 vs 20 por ciento), el estado físico y la calidad de vida de las primeras fue mucho menos satisfactorio que la de los segundos después de la cirugía. Las reintervenciones después de la cirugía por ulcus fueron en número de 35, involucrando al 38 por ciento de los pacientes. Los resultados de los pacientes utilizando la clasificación de Visick modificada, después de todas las reintervenciones, fue como sigue: I= 22; II=30; III=23 y IV= 17.Conclusiones: los resultados a largo plazo de la cirugía electiva de la úlcera duodenal no complicada no han sido muy alentadores, por lo que sugerimos para el control de esta enfermedad el tratamiento médico y sólo excepcionalmente en la úlceras refractarias un tratamiento quirúrgico que minimice las complicaciones a largo plazo (AU)

[Impact of air pollution on the mortality and emergencies of chronic obstructive pulmonary disease and asthma in Barcelona]. / Impacto de la contaminación atmosférica sobre la mortalidad y las urgencias por enfermedad pulmonar obstructiva crónica y asma en Barcelona.

OBJECTIVES: Air pollution has been associated with increased mortality according to studies carried out in the US. The APHEA project (Air Pollution on Health: a European Approach) analyzes the short-term effects in 15 european cities. We evaluated the acute relation between air pollution, mortality, and hospital emergency-room visits in Barcelona, one of the cities participating in the APHEA project. METHODS: Daily variations in total mortality, cardiovascular mortality, respiratory mortality, and emergency-room visits for chronic obstructive pulmonary disease (COPD), and asthma were studied in relation to daily variations in air pollution levels in 1985-1991. Poisson regression was done and temperature, relative humidity, and epidemics of asthma and flu were controlled. Temporal trends and auto-regressive terms were examined. RESULTS: A reduction of about 50 micrograms/m3 in particles and sulfur dioxide was accompanied by a reduction of about 4% and 6% (p < 0.05), respectively, in daily deaths from respiratory and cardiovascular causes and emergency-room visits for COPD. Oxidant pollutants (nitrogen dioxide and ozone) were related positively with cardiovascular mortality and emergency visits for COPD and asthma. The role of ozone was notable, with a reduction in ozone levels of 50 micrograms/m3 originating a 4% reduction in emergency-room visits for COPD and asthma (p < 0.05). CONCLUSIONS: Current levels of air pollutants had an epidemiologically measurable impact on mortality and emergency-room visits in Barcelona. These results were consistent with the findings of similar studies in other european and american cities and with previous studies of emergency-room admissions in Barcelona. These studies suggest the possible toxicity of air pollution.

Factors related to the failure of endoscopic injection therapy for bleeding gastric ulcer.

BACKGROUND: Although endoscopic injection therapy is effective in controlling initial haemorrhage from peptic ulcer, between 10% to 30% of patients suffer rebleeding. AIM: To assess the factors that may predict the failure of endoscopic injection in patients bleeding from high risk gastric ulcer. SUBJECTS: One hundred and seventy eight patients admitted for a gastric ulcer with a bleeding or a non-bleeding visible vessel were included. METHODS: Patients received endoscopic therapy by injection for adrenaline and polidocanol. Twelve clinical and endoscopic variables were entered into a multivariate logistic regression model to ascertain their significance as predictive factor of therapeutic failure. RESULTS: Eighty seven per cent (155 of 178) of patients had no further bleeding after endoscopic therapy. Endoscopic injection failed in 23 (13%) patients: 20 (12%) continued to bleed or rebleed, and three (1%) patients could not be treated because of inaccessibility of the lesion. Logistic regression analysis showed that therapeutic failure was significantly related to: (1) the presence of hypovolaemic shock (p = 0.09, OR 2.38, 95% CI: 0.86, 6.56), (2) the presence of active bleeding at endoscopy (p = 0.02, OR 2.98, 95% CI: 1.12, 7.91), (3) ulcer location high on the lesser curvature (p = 0.04, OR 2.79, 95% CI: 1.01, 7.69), and (4) ulcer size larger than 2 cm (p = 0.01, OR 3.64, 95% CI: 1.34, 9.89). CONCLUSION: These variables may enable identification of those patients bleeding from gastric ulcer who would not benefit from injection therapy.

[Comparison of two sources on mortality information in a retrospective cohort study on occupational cancer]. / Concordancia entre dos fuentes de información sobre causas de mortalidad en un estudio de seguimiento retrospectivo de cáncer ocupacional.

In the context of a historical cohort study among workers in the pulp and paper industry, we examined the agreement between the underlying cause of death obtained from municipal mortality files and from the mortality register of Catalonia (n = 50 pairs). The percentage of simple agreement (P0) for major causes of death was 76%. The agreement and the Kappa index was higher for external causes (P0 = 98%; K = 0.87) and for cancer (P0 = 90%; K = 0.79). The agreement was moderate for mortality from circulatory diseases (K = 0.57). Agreement between 3 digit ICD codes was 48% but was higher for deaths from cancer (P0 = 67%). These results indicate that information on major causes of death and on specific causes of cancer retrieved from municipal mortality files may be used for the follow-up of historical cohort studies.

Evaluation of duodenogastric reflux in gallstone disease before and after simple cholecystectomy.

Duodenogastric reflux (DGR) has been suggested as an etiopathogenic factor in gastric disease in patients with gallstones. We evaluated the DGR levels in 15 patients before and after simple cholecystectomy for gallstones and compared the results with those of 15 healthy subjects. Gastric juice was obtained by continuous nasogastric suction for 24 hours. The bile acids (BA) present in the samples were quantified by thin-layer chromatography and in situ spectrofluorometry. The mean BA concentration for the control subjects was 2.25 mumol reflux/hour, whereas the mean value for the 15 patients with cholelithiasis was 8.86 mumol reflux/hour before cholecystectomy and 24.55 mumol reflux/hour after cholecystectomy. Five patients did not have detectable BA in the gastric juice in both analyses; the remaining 10 patients showed a significant increase in the BA after surgery. From these data, we conclude that gallstone disease is not always accompanied by an increased DGR. However, in patients in whom DGR is present, its level is higher than in control subjects and increases significantly after cholecystectomy. This is probably due to the greater amount of bile in the duodenum that may reflux through an incompetent pyloric channel.

Bile reflux in postoperative alkaline reflux gastritis.

This study evaluates enterogastric reflux (EGR) levels in patients with and without symptoms of postoperative alkaline reflux gastritis (PARG) after gastric surgery. The bile acids (BA) present in the gastric juice were quantified by thin-layer chromatography and spectrofluorometry. The mean BA concentration for controls was 2.25 mumol reflux/hour, for 15 asymptomatic patients 47.94 and for 15 patients with symptoms of PARG 125.79. After biliary diversion by a Roux-en-Y anastomosis in the latter, their BA in 13 of these patients after surgery, and relapsed in only one during a 4-year follow-up. The remaining two patients had the lowest preoperative BA levels in this group. These results indicate that EGR is increased after gastric surgery more markedly indicated that EGR is increased after gastric surgery more markedly in patients with symptoms of PARG, and that patients who have high levels of EGR (more than 80 mumol BA reflux/hour) clearly benefit from biliary diversion.