Impact of a pulmonary embolism response team (PERT) in the prognosis of patients with acute symptomatic pulmonary embolism

BACKGROUND

The effect of a pulmonary embolism response team (PERT) in the short-term prognosis of patients with acute symptomatic pulmonary embolism (PE) lacks clarity. We therefore aimed at evaluating the effect of a PERT team on short-term mortality among patients with acute PE.

METHODS

We retrospectively reviewed consecutive patients with acute symptomatic PE enrolled in a single-center registry between 2007 and 2022. We used propensity score matching to compare treatment effects for patients with similar predicted probabilities of receiving management by the PERT team. The primary outcome was all-cause mortality within 30 days following the diagnosis of PE. The secondary outcome was 30-day PE-related mortality.

RESULTS

Of the 2,902 eligible patients who had acute symptomatic PE, 223 (7.7%; 95% confidence interval [CI], 6.7%-8.7%) were managed by the PERT team. Two hundred and seven patients who were treated by the PERT were matched with 207 patients who were not. Matched pairs did not show a statistically significant lower all-cause (odds ratio [OR], 1.09; 95% CI, 0.63-1.89) or PE-related death (OR, 1.30; 95% CI, 0.47-3.62) for PERT management compared with no PERT management through 30 days after diagnosis of PE.

CONCLUSIONS

Our results suggest that multidisciplinary care of patients with acute symptomatic PE by a PERT team is not associated with a significant reduction in short-term all-cause or PE-related mortality.

Reconfigurable frequency multipliers based on graphene field-effect transistors

Run-time device-level reconfigurability has the potential to boost the performance and functionality of numerous circuits beyond the limits imposed by the integration density. The key ingredient for the implementation of reconfigurable electronics lies in ambipolarity, which is easily accessible in a substantial number of two-dimensional materials, either by contact engineering or architecture device-level design. In this work, we showcase graphene as an optimal solution to implement high-frequency reconfigurable electronics. We propose and analyze a split-gate graphene field-effect transistor, demonstrating its capability to perform as a dynamically tunable frequency multiplier. The study is based on a physically based numerical simulator validated and tested against experiments. The proposed architecture is evaluated in terms of its performance as a tunable frequency multiplier, able to switch between doubler, tripler or quadrupler operation modes. Different material and device parameters are analyzed, and their impact is assessed in terms of the reconfigurable graphene frequency multiplier performance.

Immunouniverse of SARS-CoV-2

SARS-CoV-2 virus has become a global health problem that has caused millions of deaths worldwide. The infection can present with multiple clinical features ranging from asymptomatic or mildly symptomatic patients to patients with severe or critical illness that can even lead to death. Although the immune system plays an important role in pathogen control, SARS-CoV-2 can drive dysregulation of this response and trigger severe immunopathology. Exploring the mechanisms of the immune response involved in host defense against SARS-CoV-2 allows us to understand its immunopathogenesis and possibly detect features that can be used as potential therapies to eliminate the virus. The main objective of this review on SARS-CoV-2 is to highlight the interaction between the virus and the immune response. We explore the function and action of the immune system, the expression of molecules at the site of infection that cause hyperinflammation and hypercoagulation disorders, the factors leading to the development of pneumonia and subsequent severe acute respiratory distress syndrome which is the leading cause of death in patients with COVID-19.

Sepsis Code: dodging mortality in a tertiary hospital

Introducción

En el hospital de La Princesa comienza el “Código Sepsis” (CSP) en el año 2015, como un grupo multidisciplinar que dota al personal sanitario de herramientas clínicas, analíticas y organizativas, con el objetivo de la detección y el tratamiento precoz del paciente con sepsis. El objetivo de este estudio es evaluar el impacto de la implantación de CSP en la mortalidad y determinar las variables asociadas con un aumento de la misma.

Material y métodos

Se realizó un estudio analítico retrospectivo de los pacientes con activación de la alerta CSP de 2015 a 2018. Se recogieron variables clínico-epidemiológicas, parámetros analíticos y factores de gravedad como el ingreso en Unidades de Cuidados Críticos (UCC) y la necesidad de aminas. La significación estadística se estableció en una p < 0,05.

Resultados

Se incluyeron 1.121 pacientes. La estancia media fue de 16 días y un 32% requirieron ingreso en UCC. La mortalidad mostró una tendencia lineal descendente estadísticamente significativa del 24% en 2015 hasta el 15% en 2018. Las variables predictivas de mortalidad con asociación estadísticamente significativa fueron el lactato > 2 mmol/L, la creatinina > 1,6 mg/dL y la necesidad de aminas.

Conclusiones

La implementación de Código Sepsis disminuye la mortalidad de los pacientes con sepsis y shock séptico. La presencia de una cifra de lactato > 2 mmol/L, los niveles de creatinina > 1,6 mg/dL y/o la necesidad de administrar aminas en las primeras 24 horas, se asocian con un aumento de la mortalidad en el paciente con sepsis.

Multi-scale analysis of radio-frequency performance of 2D-material based field-effect transistors

Two-dimensional materials (2DMs) are a promising alternative to complement and upgrade high-frequency electronics. However, in order to boost their adoption, the availability of numerical tools and physically-based models able to support the experimental activities and to provide them with useful guidelines becomes essential. In this context, we propose a theoretical approach that combines numerical simulations and small-signal modeling to analyze 2DM-based FETs for radio-frequency applications. This multi-scale scheme takes into account non-idealities, such as interface traps, carrier velocity saturation, or short channel effects, by means of self-consistent physics-based numerical calculations that later feed the circuit level via a small-signal model based on the dynamic intrinsic capacitances of the device. At the circuit stage, the possibilities range from the evaluation of the performance of a single device to the design of complex circuits combining multiple transistors. In this work, we validate our scheme against experimental results and exemplify its use and capability assessing the impact of the channel scaling on the performance of MoS₂-based FETs targeting RF applications.

Comparative clinical prognosis of massive and non-massive pulmonary embolism: A registry-based cohort study

AIMS

Little is known about the prognosis of patients with massive pulmonary embolism (PE) and its risk of recurrent venous thromboembolism (VTE) compared with non-massive PE, which may inform clinical decisions. Our aim was to compare the risk of recurrent VTE, bleeding, and mortality after massive and non-massive PE during anticoagulation and after its discontinuation.

METHODS AND RESULTS

We included all participants in the RIETE registry who suffered a symptomatic, objectively confirmed segmental or more central PE. Massive PE was defined by a systolic hypotension at clinical presentation (<90 mm Hg). We compared the risks of recurrent VTE, major bleeding, and mortality using time-to-event multivariable competing risk modeling. There were 3.5% of massive PE among 38 996 patients with PE. During the anticoagulation period, massive PE was associated with a greater risk of major bleeding (subhazard ratio [sHR] 1.72, 95% confidence interval [CI] 1.28-2.32), but not of recurrent VTE (sHR 1.15, 95% CI 0.75-1.74) than non-massive PE. An increased risk of mortality was only observed in the first month after PE. After discontinuation of anticoagulation, among 11 579 patients, massive PE and non-massive PE had similar risks of mortality, bleeding, and recurrent VTE (sHR 0.85, 95% CI 0.51-1.40), but with different case fatality of recurrent PE (11.1% versus 2.4%, P = .03) and possibly different risk of recurrent fatal PE (sHR 3.65, 95% CI 0.82-16.24).

CONCLUSION

In this large prospective registry, the baseline hemodynamic status of the incident PE did not influence the risk of recurrent VTE, during and after the anticoagulation periods, but was possibly associated with recurrent PE of greater severity.

Outcome of Patients with Venous Thromboembolism and Factor V Leiden or Prothrombin 20210 Carrier Mutations During the Course of Anticoagulation

BACKGROUND

Individuals with factor V Leiden or prothrombin G20210A mutations are at a higher risk to develop venous thromboembolism. However, the influence of these polymorphisms on patient outcome during anticoagulant therapy has not been consistently explored.

METHODS

We used the Registro Informatizado de Enfermedad TromboEmbólica database to compare rates of venous thromboembolism recurrence and bleeding events occurring during the anticoagulation course in factor V Leiden carriers, prothrombin mutation carriers, and noncarriers.

RESULTS

Between March 2001 and December 2015, 10,139 patients underwent thrombophilia testing. Of these, 1384 were factor V Leiden carriers, 1115 were prothrombin mutation carriers, and 7640 were noncarriers. During the anticoagulation course, 160 patients developed recurrent deep vein thrombosis and 94 patients developed pulmonary embolism (16 died); 154 patients had major bleeding (10 died), and 291 patients had nonmajor bleeding. On multivariable analysis, factor V Leiden carriers had a similar rate of venous thromboembolism recurrence (adjusted hazard ratio [HR], 1.16; 95% confidence interval [CI], 0.82-1.64), half the rate of major bleeding (adjusted HR, 0.50; 95% CI, 0.25-0.99) and a nonsignificantly lower rate of nonmajor bleeding (adjusted HR, 0.66; 95% CI, 0.43-1.01) than noncarriers. Prothrombin mutation carriers and noncarriers had a comparable rate of venous thromboembolism recurrence (adjusted HR, 1.00; 95% CI, 0.68-1.48), major bleeding (adjusted HR, 0.75; 95% CI, 0.42-1.34), and nonmajor bleeding events (adjusted HR, 1.10; 95% CI, 0.77-1.57).

CONCLUSIONS

During the anticoagulation course, factor V Leiden carriers had a similar risk for venous thromboembolism recurrence and half the risk for major bleeding compared with noncarriers. This finding may contribute to decision-making regarding anticoagulation duration in selected factor V Leiden carriers with venous thromboembolism.

The Clinical Course of Venous Thromboembolism May Differ According to Cancer Site

BACKGROUND

We hypothesized that the clinical course of venous thromboembolism in patients with active cancer may differ according to the specificities of primary tumor site.

AIM AND METHODS

We used data from RIETE (international registry of patients with venous thromboembolism) to compare the clinical venous thromboembolism-related outcomes during the course of anticoagulation in patients with one of the 4 more frequent cancers (breast, prostate, colorectal, or lung cancer).

RESULTS

As of September 2014, 3947 cancer patients were recruited, of whom 938 had breast, 629 prostate, 1189 colorectal, and 1191 lung cancer. Overall, 55% had metastatic disease (42%, 36%, 53%, and 72%, respectively). During the course of anticoagulant therapy (mean duration, 139 days), the rate of thromboembolic recurrences was similar to the rate of major bleeding in patients with breast (5.6 [95% confidence interval (CI), 3.8-8.1] vs 4.1 [95% CI, 2.7-5.9] events per 100 patient-years) or colorectal cancer (10 [95% CI, 7.6-13] vs 12 [95% CI, 9.4-15] per 100 patient-years). In contrast, in patients with prostate cancer, the rate of venous thromboembolic recurrences was half the rate of major bleeding (6.9 [95% CI, 4.4-10] vs 13 [95% CI, 9.2-17] events per 100 patient-years), whereas in those with lung cancer, the rate of thromboembolic recurrences was twofold higher than the rate of major bleeding (27 [95% CI, 22-23] vs 11 [95% CI, 8.6-15] per 100 patient-years).

CONCLUSIONS

Significant differences in the clinical profile of venous thromboembolic-related outcomes were observed according to the site of cancer. These findings suggest the development of cancer-specific anticoagulant strategies as an area for further research.

Risk of recurrent venous thromboembolism and major hemorrhage in cancer-associated incidental pulmonary embolism among treated and untreated patients: a pooled analysis of 926 patients

ESSENTIALS: We performed a pooled analysis of 926 patients with cancer-associated incidental pulmonary embolism (IPE). Vitamin K antagonists (VKA) are associated with a higher risk of major hemorrhage. Recurrence risk is comparable after subsegmental and more proximally localized IPE. Our results support low molecular weight heparins over VKA and similar management of subsegmental IPE.

BACKGROUND

Incidental pulmonary embolism (IPE) is defined as pulmonary embolism (PE) diagnosed on computed tomography scanning not performed for suspected PE. IPE has been estimated to occur in 3.1% of all cancer patients and is a growing challenge for clinicians and patients. Nevertheless, knowledge about the treatment and prognosis of cancer-associated IPE is scarce. We aimed to provide the best available evidence on IPE management.

METHODS

Incidence rates of symptomatic recurrent venous thromboembolism (VTE), major hemorrhage, and mortality during 6-month follow-up were pooled using individual patient data from studies identified by a systematic literature search. Subgroup analyses based on cancer stage, thrombus localization, and management were performed.

RESULTS

In 926 cancer patients with IPE from 11 cohorts, weighted pooled 6-month risks of recurrent VTE, major hemorrhage and mortality were 5.8% (95% confidence interval [CI] 3.7-8.3%), 4.7% (95% CI 3.0-6.8%), and 37% (95% CI 28-47%). VTE recurrence risk was comparable under low molecular weight heparins (LMWH) and vitamin K antagonists (VKAs) (6.2% vs. 6.4%; hazard ratio [HR] 0.9; 95% CI 0.3-3.1), while 12% in untreated patients (HR 2.6; 95% CI 0.91-7.3). Risk of major hemorrhage was higher under VKAs than under LMWH (13% vs. 3.9%; HR 3.9; 95% CI 1.6-10). VTE recurrence risk was comparable in patients with an subsegmental IPE and those with a more proximally localized IPE (HR 1.1; 95% CI 0.50-2.4).

CONCLUSION

These results support the current recommendation to anticoagulate cancer-associated IPE with LMWH and argue against different management of subsegmental IPE.

Multidetector computed tomographic pulmonary angiography in patients with a high clinical probability of pulmonary embolism

ESSENTIALS: When high probability of pulmonary embolism (PE), sensitivity of computed tomography (CT) is unclear. We investigated the sensitivity of multidetector CT among 134 patients with a high probability of PE. A normal CT alone may not safely exclude PE in patients with a high clinical pretest probability. In patients with no clear alternative diagnosis after CTPA, further testing should be strongly considered.

BACKGROUND

Whether patients with a negative multidetector computed tomographic pulmonary angiography (CTPA) result and a high clinical pretest probability of pulmonary embolism (PE) should be further investigated is controversial.

METHODS

This was a prospective investigation of the sensitivity of multidetector CTPA among patients with a priori clinical assessment of a high probability of PE according to the Wells criteria. Among patients with a negative CTPA result, the diagnosis of PE required at least one of the following conditions: ventilation/perfusion lung scan showing a high probability of PE in a patient with no history of PE, abnormal findings on venous ultrasonography in a patient without previous deep vein thrombosis at that site, or the occurrence of venous thromboembolism (VTE) in a 3-month follow-up period after anticoagulation was withheld because of a negative multidetector CTPA result.

RESULTS

We identified 498 patients with a priori clinical assessment of a high probability of PE and a completed CTPA study. CTPA excluded PE in 134 patients; in these patients, the pooled incidence of VTE was 5.2% (seven of 134 patients; 95% confidence interval [CI] 1.5-9.0). Five patients had VTEs that were confirmed by an additional imaging test despite a negative CTPA result (five of 48 patients; 10.4%; 95% CI 1.8-19.1), and two patients had objectively confirmed VTEs that occurred during clinical follow-up of at least 3 months (two of 86 patients; 2.3%; 95% CI 0-5.5). None of the patients had a fatal PE during follow-up.

CONCLUSIONS

A normal multidetector CTPA result alone may not safely exclude PE in patients with a high clinical pretest probability.

Lack of early inbreeding depression and distribution of selfing rates in the neotropical emergent tree Ceiba pentandra: Assessment from several reproductive events

PREMISE OF THE STUDY

Selfing and mixed mating systems are prevalent in many flowering plants. Purging of genetic load can occur in these species, reducing negative effects of selfing. Long-term studies of the temporal and spatial variation of selfing rates and inbreeding depression at the individual level are necessary to understand the forces that maintain selfing as a mating strategy in these species.

METHODOLOGY

We used microsatellites to estimate selfing rates in seeds and seedlings over 6 years in a population of Ceiba pentandra in southwestern Costa Rica. We studied the correlation of selfing with early seedling vigor variables to test for inbreeding depression.

KEY RESULTS

Selfing rates varied widely among maternal trees. However, we found high consistency of selfing rates for individuals among years. Selfing rate did not influence early fitness traits, suggesting a lack of inbreeding depression at this stage. Maternal effects were a predominant source of variation for early vigor variables.

CONCLUSIONS

Variability in selfing rates among trees may be partly explained by genetic variation in a late-acting self-incompatibility system or low, early-acting genetic load in some individuals. This population did not show evidence of early inbreeding depression in traits related to seed vigor probably from complete or partial purging as a result of repeated selfing of a fraction of the population or from strong maternal effects. Expression of genetic load at later developmental stages or in more stressful natural conditions may explain differences in inbreeding levels between seeds and adults.

A prognostic score to identify low-risk outpatients with acute deep vein thrombosis in the lower limbs

BACKGROUND

No prior studies have identified which patients with deep vein thrombosis in the lower limbs are at a low risk for adverse events within the first week of therapy.

METHODS

We used data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) to identify patients at low risk for the composite outcome of pulmonary embolism, major bleeding, or death within the first week. We built a prognostic score and compared it with the decision to treat patients at home.

RESULTS

As of December 2013, 15,280 outpatients with deep vein thrombosis had been enrolled. Overall, 5164 patients (34%) were treated at home. Of these, 12 (0.23%) had pulmonary embolism, 8 (0.15%) bled, and 4 (0.08%) died. On multivariable analysis, chronic heart failure, recent immobility, recent bleeding, cancer, renal insufficiency, and abnormal platelet count independently predicted the risk for the composite outcome. Among 11,430 patients (75%) considered to be at low risk, 15 (0.13%) suffered pulmonary embolism, 22 (0.19%) bled, and 8 (0.07%) died. The C-statistic was 0.61 (95% confidence interval [CI], 0.57-0.65) for the decision to treat patients at home and 0.76 (95% CI, 0.72-0.79) for the score (P = .003). Net reclassification improvement was 41% (P < .001). Integrated discrimination improvement was 0.034 for the score and 0.015 for the clinical decision (P < .001).

CONCLUSIONS

Using 6 easily available variables, we identified outpatients with deep vein thrombosis at low risk for adverse events within the first week. These data may help to safely treat more patients at home. This score, however, should be validated.

POEMS syndrome as an uncommon cause of papilledema

BACKGROUND

Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome is an uncommon condition related to a paraneoplastic syndrome secondary to an underlying plasma cell disorder. Among the myriad of manifestations of the disease, ocular signs and symptoms are relatively prevalent, affecting about half of all patients with the disease.

OBJECTIVE

To report the ocular manifestations of POEMS syndrome.

CASE

A 47-year-old lady diagnosed to have POEMS syndrome presented with painless progressive visual diminution. Her color vision was impaired. There was bilateral papilloedema.

CONCLUSION

POEMS syndrome should be considered among the differential diagnoses of all patients with a bilateral papilledema in which no other cause can be readily elucidated.

Prognostic significance of tricuspid annular displacement in normotensive patients with acute symptomatic pulmonary embolism

BACKGROUND

Tricuspid annular plane systolic excursion (TAPSE) is an emerging prognostic indicator in patients with acute symptomatic pulmonary embolism (PE).

METHODS AND RESULTS

We prospectively examined 782 normotensive patients with PE who underwent echocardiography in a multicenter study. As compared with patients with a TAPSE of > 1.6 cm, those with a TAPSE of ≤ 1.6 cm had increased systolic pulmonary artery pressure (53.7 ± 16.7 mmHg vs. 40.0 ± 15.5 mmHg, P < 0.001), right ventricle (RV) end-diastolic diameter (3.5 ± 0.8 cm vs. 3.0 ± 0.6 cm, P < 0.001), and RV to left ventricle end-diastolic diameter ratio (1.0 ± 0.3 vs. 0.8 ± 0.2, P < 0.001), and a higher prevalence of RV free wall hypokinesis (68% vs. 11%, P < 0.001). Patients with a TAPSE of ≤ 1.6 cm at the time of PE diagnosis were significantly more likely to die from any cause (hazard ratio [HR] 2.3; 95% confidence interval [CI] 1.2-4.7; P = 0.02) and from PE (HR 4.4; 95% CI 1.3-15.3; P = 0.02) during follow-up. In an external validation cohort of 1326 patients with acute PE enrolled in the international multicenter Registro Informatizado de la Enfermedad TromboEmbólica, a TAPSE of ≤ 1.6 cm remained a significant predictor of all-cause mortality (HR 2.1; 95% CI 1.3-3.2; P = 0.001) and PE-specific mortality (HR 2.5; 95% CI 1.2-5.2; P = 0.01).

CONCLUSIONS

In normotensive patients with PE, TAPSE reflects right ventricular function. For these patients, TAPSE is independently predictive of survival.

Serosurveillance of infectious agents in equines of the Central Valley of Costa Rica

Blood samples from 181 equines from the Central Valley of Costa Rica were collected in the year 2012 to determine the presence of antibodies against selected infectious agents in horses and to determine the risk factors associated with these agents. The presence of antibodies against Equine Infectious Anemia Virus (EIAV), Equine Herpes Virus 1 and 4 (EHV-1 and EHV-4), West Nile Virus (WNV), Influenza A Virus (IAV), Equine Viral Arteritis Virus (EVAV), Babesia caballi, Theileria equi, Neospora caninum and Chlamydia abortus was determined using commercial assays, and risk factors associated with seropositivity to the different infectious agents was established. The most seroprevalent agent detected was EHV-4 (96.7%), followed by WNV (44.2%), and IAV (41.8%). Horses >3 years, used for work or sports, and with access to pastures, had significantly increased probability to be seropositive to WNV, whereas horses used for breeding and recreational purposes, being stabled, and without access to pastures, had significantly greater probability to be seropositive to IAV. Seroprevalence to B. caballi (19.9%) was lower than to T. equi (38.1%). For B. caballi, access to pastures was determined as a risk factor, whereas being older than 3 years was established as a risk factor for T. equi. Low seroprevalences were determined for EHV-1 (5.0%), EVAV (5.0%), C. abortus (4.8%), and N. caninum (4.4%). Mares having history of abortion were more likely to be seropositive to EHV-1, whereas horses >3 years, used for work and sports, and mares having multiple parturitions, were more likely to be seropositive to N. caninum. None of the horses were seropositive to EIAV. Earlier, only diseases caused by EIAV, WNV and piroplasmosis were reported in Costa Rica. The present study however, determined the presence of carriers for EHV-1, EHV-4, and EIAV.

Computed tomography-assessed right ventricular dysfunction and risk stratification of patients with acute non-massive pulmonary embolism: systematic review and meta-analysis

BACKGROUND

The ability of computed tomography (CT)-assessed right ventricular dysfunction (RVD) to identify normotensive patients with acute pulmonary embolism (PE) at high risk of mortality or adverse outcome lacks clarity.

METHODS AND RESULTS

We performed a systematic review and a meta-analysis of studies in normotensive patients with acute PE to assess the prognostic value of CT-assessed RVD for death and a predefined composite outcome of PE-related complications. We conducted unrestricted searches of MEDLINE and EMBASE from 1980 to March 2013, and used the terms 'computed tomography', 'pulmonary embolism', and 'prognos*'. We used a random-effects model to pool study results, funnel-plot inspection to evaluate for publication bias, and I(2) testing to assess for heterogeneity. The analysis included data from 10 studies (2288 patients). Overall, 99 of 1268 patients with RVD assessed by CT died (7.8%; 95% confidence interval [CI] 6.3-9.3) as compared with 52 of 1020 without RVD (5.1%; 95% CI 3.7-6.4). CT-assessed RVD had significant associations with mortality (odds ratio [OR] 1.8; 95% CI 1.3-2.6), with death resulting from PE (OR 7.4; 95% CI 1.4-39.5), and with PE-related complications (OR 2.4; 95% CI 1.2-4.7). Pooled likelihood ratios (LRs) were not extreme (negative LR 0.71; 95% CI 0.57-0.89; and positive LR 1.27; 95% CI 1.12-1.43).

CONCLUSIONS

Although RVD assessed by CT showed an association with an increased risk of mortality in patients with hemodynamically stable PE, it resulted in only small increases in the ability to classify risk.

Influence of recent immobilization and recent surgery on mortality in patients with pulmonary embolism

BACKGROUND

The influence of recent immobilization or surgery on mortality in patients with pulmonary embolism (PE) is not well known.

METHODS

We used the Registro Informatizado de Enfermedad TromboEmbólica (RIETE) data to compare the 3-month mortality rate in patients with PE, with patients categorized according to the presence of recent immobilization, recent surgery, or neither.

RESULTS

Of 18,028 patients with PE, 4169 (23%) had recent immobilization, 2212 (12%) had recent surgery, and 11,647 (65%) had neither. The all-cause mortality was 10.0% (95% confidence interval [CI] 9.5-10.4), and the PE-related mortality was 2.6% (95% CI 2.4-2.9). One in every two patients who died from PE had recent immobilization (43%) or recent surgery (6.7%). Only 25% of patients with immobilization had received prophylaxis, as compared with 65% of the surgical patients. Fatal PE was more common in patients with recent immobilization (4.9%; 95% CI 4.3-5.6) than in those with surgery (1.4%; 95% CI 1.0-2.0) or those with neither (2.1%; 95% CI 1.8-2.3). On multivariate analysis, patients with immobilization were at increased risk for fatal PE (odds ratio 2.2; 95% CI 1.8-2.7), with no differences being seen between patients immobilized in hospital or in the community.

CONCLUSIONS

Forty-three per cent of patients dying from PE had recent immobilization for ≥4 days. Many of these deaths could have been prevented.

Thrombolytic therapy and outcome of patients with an acute symptomatic pulmonary embolism

BACKGROUND

While the primary therapy for most patients with a pulmonary embolism (PE) consists of anticoagulation, the efficacy of thrombolysis relative to standard therapy remains unclear.

METHODS

In this retrospective cohort study of 15,944 patients with an objectively confirmed symptomatic acute PE, identified from the multicenter, international, prospective, Registro Informatizado de la Enfermedad TromboEmbólica (RIETE registry), we aimed to assess the association between thrombolytic therapy and all-cause mortality during the first 3 months after the diagnosis of a PE. After creating two subgroups, stratified by systolic blood pressure (SBP) (< 100 mm Hg vs. other), we used propensity score-matching for a comparison of patients who received thrombolysis to those who did not in each subgroup.

RESULTS

Patients who received thrombolysis were younger, had fewer comorbid diseases and more signs of clinical severity compared with those who did not receive it. In the subgroup with systolic hypotension, analysis of propensity score-matched pairs (n = 94 pairs) showed a non-statistically significant but clinically relevant lower risk of death for thrombolysis compared with no thrombolysis (odds ratio [OR] 0.72; 95% confidence interval [CI], 0.36-1.46; P = 0.37). In the normotensive subgroup, analysis of propensity score-matched pairs (n = 217 pairs) showed a statistically significant and clinically meaningful increased risk of death for thrombolysis compared with no thrombolysis (OR 2.32; 95% CI, 1.15-4.68; P = 0.018). When we imputed data for missing values for echocardiography and troponin tests in the group of normotensive patients, we no longer detected the increased risk of death associated with thrombolytic therapy.

CONCLUSIONS

In normotensive patients with acute symptomatic PE, thrombolytic therapy is associated with a higher risk of death than no thrombolytic therapy. In hemodynamically unstable patients, thrombolytic therapy is possibly associated with a lower risk of death than no thrombolytic therapy. However, study design limitations do not imply a causal relationship between thrombolytics and outcome.

Silent pulmonary embolism in patients with proximal deep vein thrombosis in the lower limbs

BACKGROUND

One in every three patients with deep vein thrombosis (DVT) in the lower limbs may have silent pulmonary embolism (PE), but its clinical relevance has not been thoroughly studied.

METHODS

We used the RIETE Registry data to study patients with proximal DVT and no PE symptoms, but with a systematic search for PE. We compared the outcome of DVT patients with silent PE and those with no PE.

RESULTS

Of 2375 patients with DVT, 842 (35%) had silent PE and 1533 had no PE. During the first 15 days of anticoagulation, patients presenting with silent PE had a higher incidence of symptomatic PE events than those with no PE (0.95% vs. 0.13%; P = 0.015), with a similar incidence of major bleeding (0.95% vs. 1.63%; P = 0.09). In patients with silent PE, the incidence of PE events during the first 15 days was equal to the incidence of major bleeding (eight events each), but in those with no PE the incidence of PE events was eight times lower (3 vs. 25 bleeding events). Multivariate analysis confirmed that DVT patients with silent PE had a higher incidence of symptomatic PE events during the first 15 days than those with no PE (odds ratio, 4.80; 95% CI, 1.27-18.1), with no differences in bleeding.

CONCLUSIONS

DVT patients with silent PE at baseline had an increased incidence of symptomatic PE events during the first 15 days of anticoagulant therapy. This effect disappeared after 3 months of anticoagulation.

The effects of cause of death classification on prognostic assessment of patients with pulmonary embolism

BACKGROUND

Although previous studies have provided evidence that the majority of deaths following an acute pulmonary embolism (PE) directly relate to the PE, more recent registries and cohort studies suggest otherwise.

METHODS

We assessed the cause of death during the first 30 days after the diagnosis of acute symptomatic PE in a consecutive series of patients. We also assessed the prognostic characteristics of the simplified Pulmonary Embolism Severity Index (sPESI) and cardiac troponin I (cTnI) obtained at the time of PE diagnosis.

RESULTS

During the first 30 days after diagnosis, 127 of the 1291 patients died (9.8%; 95% confidence interval [CI], 8.2-11.5). Sixty patients (4.6%; 95% CI, 3.5-5.8) died from definite or possible PE, and 67 (5.2%; 95% CI, 4.0-6.4) died from other causes (cancer 25, infection 18, hemorrhage 7, heart failure 7, chronic obstructive pulmonary disease 5, renal failure 1, seizures 1, unknown 3). The sPESI predicted all-cause (odds ratio [OR], 5.97; 95% CI, 1.74-20.54; P < 0.01) and PE-associated mortality (OR, 8.79; 95% CI, 1.12-68.79; P = 0.04). cTnI only predicted PE-associated mortality (adjusted OR, 2.39; 95% CI, 1.25-4.57; P < 0.01). For all-cause mortality, the sPESI low-risk strata had a negative predictive value of 98.8% (95% CI, 97.4-100) in comparison with 91.3% (95% CI, 88.9-93.6) for the cTnI.

CONCLUSIONS

Within the first 30 days after the diagnosis of acute symptomatic PE, death due to PE and death due to other causes occur in a similar proportion of patients. As cTnI only predicted PE-associated mortality, low-risk sPESI had a higher negative predictive value for all-cause mortality compared with cTnI.

Validation of a clinical algorithm to identify low-risk patients with pulmonary embolism

BACKGROUND

We previously derived a clinical prognostic algorithm to identify patients with pulmonary embolism (PE) who are at low risk of short-term mortality and who could be safely discharged early or treated entirely in an outpatient setting.

OBJECTIVES

To externally validate the clinical prognostic algorithm in an independent patient sample.

METHODS

We validated the algorithm in 983 consecutive patients prospectively diagnosed with PE at an emergency department of a university hospital. Patients with none of the algorithm's 10 prognostic variables (age > or = 70 years, cancer, heart failure, chronic lung disease, chronic renal disease, cerebrovascular disease, pulse > or = 110 min(-1), systolic blood pressure < 100 mmHg, oxygen saturation < 90%, and altered mental status) at baseline were defined as being at low risk. We compared 30-day overall mortality among low-risk patients, on the basis of the algorithm, between the validation sample and the original derivation sample. We also assessed the rate of PE-related and bleeding-related mortality among low-risk patients.

RESULTS

Overall, the algorithm classified 16.3% of patients with PE as being at low risk. Mortality at 30 days was 1.9% among low-risk patients, and did not differ between the validation sample and the original derivation sample. Among low-risk patients, only 0.6% died from definite or possible PE, and 0% died from bleeding.

CONCLUSIONS

This study validates an easy-to-use, clinical prognostic algorithm for PE that accurately identifies patients with PE who are at low risk of short-term mortality. Patients who are at low risk according to our algorithm are potential candidates for less costly outpatient treatment.

Pulmonary Embolism Severity Index and troponin testing for the selection of low-risk patients with acute symptomatic pulmonary embolism

BACKGROUND

The combination of the Pulmonary Embolism Severity Index (PESI) and troponin testing could help physicians identify appropriate patients with acute pulmonary embolism (PE) for early hospital discharge.

METHODS

This prospective cohort study included a total of 567 patients from a single center registry with objectively confirmed acute symptomatic PE. On the basis of the PESI, each patient was classified into one of five classes (I-V). At the time of hospital admission, patients had troponin I (cTnI) levels measured. The endpoint of the study was all-cause mortality within 30 days after diagnosis. We calculated the mortality rates in four patient groups: group 1, PESI class I-II plus cTnI < 0.1 ng mL(-1); group 2, PESI classes III-V plus cTnI < 0.1 ng mL(-1); group 3, PESI classes I-II plus cTnI > or = 0.1 ng mL(-1); and group 4, PESI classes III-V plus cTnI > or = 0.1 ng mL(-1).

RESULTS

The study cohort had a 30-day mortality of 10% [95% confidence interval (CI), 7.6-12.5%]. Mortality rates in the four groups were 1.3%, 14.2%, 0% and 15.4%, respectively. Compared with non-elevated cTnl, the low-risk PESI had a higher negative predictive value (NPV) (98.9% vs. 90.8%) and negative likelihood ratio (NLR) (0.1 vs. 0.9) for predicting mortality. The addition of non-elevated cTnI to low-risk PESI did not improve the NPV or the NLR compared with either test alone.

CONCLUSIONS

Compared with cTnl testing, PESI classification more accurately identified patients with PE who are at low risk of all-cause death within 30 days of presentation.

Multi-channel receptors based on thiopyrylium functionalised with macrocyclic receptors for the recognition of transition metal cations and anions

We report herein the synthesis and characterization of a family of ligands containing different cation binding sites covalently connected to a thiopyrylium signalling reporter. The receptors L1-L6 are able to signal the presence of certain metal cations via three different channels; i.e. electrochemically, fluorogenically and chromogenically. An acetonitrile solution of L1-L6 shows a bright blue colour due to a charge-transfer band in the 575-585 nm region. The colour variation in acetonitrile of L1-L6 in the presence of the metal cations Ag+, Cd2+, Cu2+, Fe3+, Hg2+, Ni2+, Pb2+ and Zn2+ has been studied. A selective hypsochromic shift of the blue band was found for the systems L4-Pb2+ and L5-Hg2+. Additionally, L1-L6 are poorly fluorescent but coordination with certain metal cations induces an enhancement of the fluorescence at ca 500 nm. For instance, the presence of Cu2+ and Fe3+ induced a remarkable 42-fold and 45-fold enhancement in the emission intensity of L1 centred at 500 nm, respectively. Also remarkable was the 18-fold enhancement observed for L4 and L5 in the presence of Fe3+ and Cu2+, respectively. The electrochemical behaviour of receptors L1-L6 was studied in acetonitrile using platinum as a working electrode and [Bu4N][BF4] as a supporting electrolyte. This family of receptors showed a one-electron reversible redox process at ca. -0.46 V versus sce attributed to the reduction of the thiopyrylium group. A moderate anodic shift in the presence of certain metal cations was observed. The effect in the UV-visible spectra of acetonitrile solutions of receptor L1-L6 in the presence of anions was also studied. A remarkable bleaching was found in the presence of cyanide.

D-dimer levels and 15-day outcome in acute pulmonary embolism. Findings from the RIETE Registry

BACKGROUND

A number of variables have been evaluated for risk stratification in patients with acute pulmonary embolism (PE). Whereas increased D-dimer levels have been associated with mortality at 3 months, its role in predicting short-term outcome (the period of time during which any therapeutic decision has to be taken) remains unclear.

METHODS

RIETE is an ongoing, prospective registry of consecutive patients with acute venous thromboembolism. We assessed the prognostic value of D-dimer levels at baseline, measured with an automated latex agglutination test (IL Test D-dimer), on the 15-day outcome in patients with acute PE. Overall mortality, fatal PE and major bleeding rates were compared by quartile.

RESULTS

As of February 2008, 1707 patients with acute PE underwent D-dimer testing. Of these, 72 patients (4.2%) died during the first 15 days, 11 (0.6%) had recurrent PE, and 29 (1.7%) had major bleeding. Overall mortality increased with increasing D-dimer levels, from 2.7% in the first quartile (< 1050 ng mL(-1)) to 7.0% in the fourth quartile (>or= 4200 ng mL(-1)). The rates of fatal PE and major bleeding also increased. On multivariate analysis, patients with D-dimer levels in the fourth quartile had an increased risk for overall death (odds ratio, 1.8; 95% CI, 1.1-3.2), fatal PE (odds ratio, 2.0; 95% CI, 1.0-3.8) or major bleeding (odds ratio, 3.2; 95% CI, 1.5-7.0).

CONCLUSIONS

PE patients with D-dimer levels in the fourth quartile had an increased incidence of overall death, fatal PE and major bleeding within 15 days both before and after multivariate adjustment.

Short-term prognosis of pulmonary embolism

Risk stratification tools that accurately quantify the prognosis of patients with pulmonary embolism (PE) may be useful in guiding medical decision making. Prospective studies demonstrated that clinical factors, echocardiographic right ventricular dysfunction, and cardiac biomarkers (troponins, brain natriuretic peptides) are independent predictors of short-term mortality in patients with PE. The presence of systemic hypotension or shock carries the highest risk of death, and thrombolysis is usually indicated. Among hemodynamically stable patients, clinical prognostic models, echocardiography, and biomarkers accurately identify low-risk patients with PE who are potential candidates for less costly outpatient care. However, the practical use of these prognostic measures is currently limited by the lack of studies demonstrating a positive impact on patient care. The benefit of risk stratification strategies based on clinical prognostic models, echocardiography, and cardiac biomarkers should be demonstrated in prospective studies before their implementation as decision aid to guide initial treatment can be recommended.

Routine use of pleural fluid cultures. Are they indicated? Limited yield, minimal impact on treatment decisions

In pleural infection, it has been recommended that Gram stain and cultures should be obtained on a routine basis. However, this recommendation has not been tested prospectively. We evaluated the yield of microbiological studies in 259 patients with parapneumonic pleural effusion. Microbiological studies were positive on the pleural fluid of 50 patients (19.3%). In 48 of the 50 patients with positive microbiological results (96%), the need for pleural drainage was correctly predicted by pleural fluid parameters. There were no differences in hospital stay (9.5+/-2.5 days versus 9.9+/-3.2 days, P=0.68) or in mortality (2 deaths in each group, P=0.58) between the group of patients in which antibiotic treatment was changed according to microbiological results and the group of patients in which it is not. In conclusion, this study demonstrates that, at least in our institution, routine microbial investigation of pleural fluid adds very little to the standard management of parapneumonic effusions.

Prognostic Value of Syncope in the Presentation of Pulmonary Embolism

OBJECTIVE

Although the prognostic value of syncope has not been specifically addressed, it has generally been considered an indicator of poor prognosis in pulmonary embolism. The objective of this study was to carry out a prospective evaluation of the risk of recurrence and/or death in patients with pulmonary embolism that presents with syncope.

PATIENTS AND METHODS

A total of 168 patients had a confirmed diagnosis of pulmonary embolism. Twelve were lost to follow up and did not enter statistical analysis. The mean follow-up period was 5 months.

RESULTS

The prevalence of syncope in the patients studied was 22%. Of the 34 patients who presented syncope, objectively confirmed recurrence occurred in 2 (5.9%). In the patients who did not present syncope, recurrence was confirmed in 8 (6.6%; P=.8). Death occurred in 2 patients (5.9%) from the group presenting syncope and 15 (12.3%) from the remaining patients in the series (P=.4). The relative risk of recurrence and/or death associated with presentation of syncope was 0.5 (95% confidence interval, 0.2-1.8). A similar risk was obtained following adjustment for the presence or absence of cancer or deep vein thrombosis.

CONCLUSIONS

Patients with pulmonary embolism that presents with syncope do not have an increased risk of recurrence and/or death.

[Spanish contribution to the clinical development of eletriptan: an analysis of controlled studies]

INTRODUCTION

Eletriptan is a recently marketed second-generation triptan with a potent agonist activity on 5-HT1B/ 1D receptors. Our aim has been to analyze the specific results from the Spanish participation in phase IIIa and IIIb clinical trials vs placebo and compare them with the results obtained in the global clinical development of eletriptan.

PATIENTS AND METHODS

Analysis of the results obtained in 40 centers in Spain (358 patients) vs global sample 4,677 patients) for the first migraine attack in 6 controlled clinical trials with eletriptan 40 mg, eletriptan 80 mg and placebo. This ad hoc analysis was carried out for those treatment groups with more than 50 patients, which reduced the final number of patients from Spain to 250.

RESULTS

The proportion of patients with relief at 2 hours (main endpoint) in the Spanish sample was 22 %, 59 % and 67 % for placebo, eletriptan 40 mg and eletriptan 80 mg, respectively. These values were significantly higher (p < 0.05) than those of placebo and similar to those from the total sample. The proportion of pain free patients at 2 hours in the Spanish sample was 10 %, 36 % and 41 % for placebo, eletriptan 40 mg and eletriptan 80 mg, respectively. These values were significantly better than those for placebo (p < 0.05) and about 15 %-20 % higher than those from the total sample. Recurrence rate in the Spanish sample was 50 %, 16 % and 25 % for placebo, eletriptan 40 and eletriptan 80 mg, respectively, and did not differ from that of the total sample. Sustained relief for the two eletriptan doses was 46 % for both eletriptan 40 and eletriptan 80, this being significant (p < 0.05) over placebo (11 %) for the Spanish sample and similar to that of the global sample. The results for other efficacy parameters, such as need of rescue medication, functional response at 2 hours, complete response for pain-freeness and acceptability followed a similar pattern. Eletriptan was, in general, well-tolerated. Adverse events were slight-moderate in intensity, transient and were not different, either in profile or proportion, from those from the global sample.

CONCLUSIONS

These results confirm eletriptan 40 mg and 80 mg as an excellent option for the symptomatic treatment of migraine in our setting.

Further studies on cortical tangential migration in wild type and Pax-6 mutant mice

In this study we present new data concerning the tangential migration from the medial and lateral ganglionic eminences (MGE and LGE) to the cerebral cortex during development. We have used Calbindin as a useful marker to follow the itinerary of tangential migratory cells during early developmental stages in wild-type and Pax-6 homozygous mutant mice. In the wild-type mice, at early developmental stages, migrating cells advance through the intermediate zone (IZ) and preplate (PP). At more advanced stages, migrating cells were present in the subplate (SP) and cortical plate (CP) to reach the entire developing cerebral cortex. We found that, in the homozygous mutant mice (Pax-6(Sey-Neu)/Pax-6(Sey-Neu)), this tangential migration is severely affected at early developmental stages: migrating cells were absent in the IZ, which were only found some days later, suggesting that in the mutant mice, there is a temporal delay in tangential migration. We have also defined some possible mechanisms to explain certain migratory routes from the basal telencephalon to the cerebral cortex. We describe the existence of two factors, which we consider to be essential for the normal migration; the first one is the cell adhesion molecule PSA-NCAM, whose role in other migratory systems is well known. The second factor is Robo-2, whose expression delimits a channel for the passage of migratory cells from the basal telencephalon to the cerebral cortex.

Yield of bronchoscopy in the diagnosis of neoplasm metastatic to lung

The yield of fiberoptic bronchoscopy (FB) in the diagnosis of pulmonary metastases has not been conveniently analyzed. With the advances in the surgery of pulmonary metastases, there is a need to evaluate the diagnostic yield and the usefulness of FB to exclude other diseases with similar radiological patterns. To determine the value of FB in the diagnosis of pulmonary metastases we have retrospectively analyzed our experience in 113 patients with proven pulmonary metastases. An endobronchial lesion was identified in 57/113 (50.4%). The most frequent tumors with endobronchial lesions were thyroid (100%), head-neck (67%) and breast carcinomas (59%). The highest diagnostic yield was obtained combining techniques of brushing, washing and biopsy (72.6%); in cases with endobronchial lesions (84.2%) and with certain histological types (head-neck 100%; breast 90.9% and colon 84.6%). The most frequent radiological findings were single or multiple nodules (77.9%). Atelectasis were associated with endobronchial lesions. In conclusion, bronchoscopy is a valuable diagnostic procedure in selected patients with metastatic lung disease.

First synthesis of the antifungal oidiolactone C from trans-communic acid: cytotoxic and antimicrobial activity in podolactone-related compounds

The synthesis of the fungicide oidiolactone C starting from diterpenic trans-communic acid was carried out with an overall yield of 11.7%. The key step in the process consists of a new bislactonization reaction catalyzed by Pd(II), which gives rise to the podolactone-type tetracyclic skeleton from a norlabdadienedioic acid. We also carried out a study of the structure-biological activity of different natural podolactones and their synthetic precursors. Thus, the highest cytotoxic activity was found in dienic dilactones with ether-type substitutions on C-17, whereas the closure of the gamma-lactone ring is not critical for presenting a maximal antimicrobial activity.

Determining the optimal number of specimens to obtain with needle biopsy of the pleura

The aim of this study was to define the number of pleural biopsy samples necessary for optimum diagnostic performance and determine to what extent they are complementary. Eighty-four closed pleural biopsies were performed in our department between June 1996 and January 1998 on 55 males and 29 females with an average age of 64.4 +/- 16.7 years. The study of the pleural fluid included: pH, biochemical testing of pleura/serum (proteins, lactate dehydrogenase, glucose, cholesterol, triglycerides, albumin and adenosine deaminase), haemogram, cytology and microbiological testing (Gram-staining, aerobes, anaerobes and mycobacteriae cultures). The biopsies were performed using a Cope needle, with a total of five biopsies for each patient: four for pathological examination (taken numerically in the order in which they were performed: D1, D2, D3 and D4) and one for microbiological testing. In those cases in which the diagnosis was uncertain or effusion persisted, a thoracoscopy or thoracotomy was performed. There were no significant differences in the diagnostic yield of each individual sample (D1, D2, D3 and D4), but there were differences in the sum of the samples, depending on the number of biopsies performed.This was true for total group and the group with carcinomas, but not for the group with tuberculosis. The increase in diagnostic yield with the number of biopsies was more remarkable in the carcinoma cases, where it increased by 35% when four biopsies were performed (54% with one biopsy versus 89% with four biopsies, P < 0.002). In conclusion, the diagnostic yield increased with the number of biopsy samples in the total group and the group with malignancy but not in the group with tuberculous effusions. The best diagnostic performance for malignant pathology was obtained with four samples. In pleural tuberculosis, the diagnostic yield did not increase with more biopsy samples. One high quality sample should be enough to obtain a diagnosis.

Comparison of highly efficient absorbing boundary conditions for the beam propagation method

Numerical experiments using the paraxial finite-difference beam propagation method have been performed with the following boundary conditions: perfectly matched layer, Higdon absorbing boundary conditions, complementary operators method, and extended complementary operators method. We have shown that Higdon operators must be modified for the paraxial wave equation to take into account the spectrum of incident rays on the boundaries of the computational domain. Reflection coefficients, accuracy, numerical dissipation/ gain, memory requirements, and time computation are compared and discussed for these absorbing techniques.

[Congenital mitral stenosis. Experience in 1991-2001]

OBJECTIVE

To describe ten years of experience with congenital mitral stenosis.

METHOD

All cases with congenital mitral stenosis from January 1991 to 2001 were analized.

RESULTS

16 patients with congenital mitral stenosis were found, mean age 3 +/- 3.08 years. TYPES OF OBSTRUCTIONS: Mitral commisures combined with tendinous cords fusion (45%), parachute mitral valve 37%, supravalvar mitral ring in one, fusion between papillary muscle and leaflets in one, and double mitral orifice in one. Hemodynamic (in mmHg) findings: wedge pressure 18.4 +/- 4, pulmonary artery systolic 61 +/- 21, diastolic 34 +/- 15, mean 47 +/- 18 mmHg, mean transvalvar gradient (MTG) 12.9 +/- 7.3, PRU 5.5 +/- 3.8. Four patients received medical treatment. Surgical results: Six patients underwent mitral repair, and four were subjected to mitral valve replacement (two with previous mitral repair). Global mortality was 2 (12.5%). Follow-up was 3.5 +/- 3 years. There was a significant difference when the initial MTG 22.6 +/- 11.5 mmHg before surgical repair was compared with the final MTG 4.75 +/- 1.5 (P < 0.05), also when initial MTG 12 +/- 2.3 before mitral valve replacement was compared with the final MTG 6 +/- 1.15 mmHg (P < 0.05).

CONCLUSION

Most patients are candidates for mitral surgical repair, however at mid term one third will require mitral valve replacement.

Circadian patterns in men acclimatized to intermittent hypoxia

Six men, normally working shifts of 7 days at high altitude (HA, 3800 m, approximately 480 mm Hg barometric pressure) followed by 7 days of rest at sea level (SL), were studied during the last days of their HA and SL shifts with a 24-h constant routine protocol of sustained wakefulness and minimal activity. The amplitude of the circadian oscillations of oxygen consumption, breathing rate, thoracic skin temperature and diastolic pressure did not differ between HA and SL. At HA, the amplitude of the tympanic and calf temperature oscillations, were, respectively, lower and higher than at SL. End-tidal P(CO2) and systolic pressure had larger amplitude oscillations at HA than at SL. Hence, also in humans, as previously shown in animals, hypoxia can affect some circadian patterns, including those involved in thermoregulation. These effects of hypoxia could contribute to sleep disturbances at HA and in patients with cardiorespiratory diseases.

Implications of the FMR1 gene in menopause: study of 147 Spanish women

OBJECTIVE

To evaluate the relationship between the FMR1 premutation and premature ovarian failure (POF) in the Spanish population and the possible incorporation of this test in gynecological procedures for women with POF or early menopause (EM).

DESIGN

Clinical and molecular genetic study. Ninety-eight premutated and six full-mutated carriers of fragile X syndrome and 43 women with POF were studied by polymerase chain reaction and Southern blot analysis for the CGG repeat expansion in the FMR1 gene.

RESULTS

Among premutated carriers, 12.2% (12 of 98) presented with POF, and 15.3% (15 of 98) presented with EM. Neither POF nor EM was observed in any of the six full-mutated women. Two women of 43 from the POF population (4.65%) were carriers for the CGG premutation in the FMR1 gene. No correlation between CGG expansion size and age at menopause was found. A biased paternal origin of the premutation and a high twinning incidence was found in all premutated women, whether they had POF or not.

CONCLUSIONS

Our data support the hypothesis that the FMR1 gene is one of the genes associated with POF and EM. Analysis of the CGG expansion in the FMR1 gene may be justified in women with POF and EM until the real role of the FMR1 premutation is determined.

Eating disorders and altered eating behaviors in adolescents of normal weight in a Spanish city

PURPOSE

To study the prevalence of altered eating behaviors or eating disorder-related behaviors among adolescents of normal weight that do not fulfill criteria for anorexia nervosa and bulimia nervosa.

METHOD

Cross-sectional study by means of a self-completed questionnaire (School of Nutrition of Granada, Spain) and measurement of weight and height in a population of 491 schoolchildren aged 14-18 years. The statistical inferences and estimation of risk are based on comparison of proportions and means test, and the relative inequality of prevalences.

RESULTS

Of 491 adolescents of normal weight, 9% (females 2:1) were following diets; 42% presented "recurrent episodes of binging" with the sensation of loss of self-control; and 41%% avoided specific types of food. Overall, 46.2% presented altered eating behavior. Factors significantly associated with this were the occurrence of periods of food abstinence and the use of purgatives [confidence interval 95% (CI 95%) prevalence ratio (PR) 1.41-2.02]. Compensatory behaviors were present in 33% of the adolescents, predominantly in females (CI 95% PR 1.79-3.07). The prevalences of abnormal eating behaviors were 16.3% for those related to anorexia (A-RB) and 17.1% for those related to bulimia (B-RB), with a clear predominance of females (2:1) and public education. There seems to be a greater aesthetic concern among those with B-RB and more worry about weight among those with A-RB.

CONCLUSIONS

A high proportion of adolescents with abnormal eating behaviors and an altered perception of body fat may currently be diagnosed as having atypical eating disorder" (Diagnostic and Statistical Manual of Mental Disorders, Fourth Revision) considering that their body mass index was within normal range.

[Acute mountain sickness at 3500 and 4250 m. A study of symptom, incidence and severity]

BACKGROUND

Acute Mountain Sickness (AMS) refers to signs and symptoms associated with hypobaric hypoxia. Its reported incidence is highly variable.

AIM

To determine the incidence of AMS symptoms and severity at 3,500 and 4,250 m above sea level.

SUBJECTS AND METHODS

A population of 362 soldiers without former exposure to altitude was studied. AMS symptoms, were assessed by an extensively used standard questionnaire (Lake Louise), applied 36-72 hours after exposure to high altitude.

RESULTS

A group of 200 recruits ascended to Putre (3,500 m) and a second group (162) ascended to Alto Pacollo (4,250 m). The incidence of AMS was 28% and 60% respectively (p < 0.05). Headaches and sleeping difficulties were the most frequent symptoms at both altitudes. Furthermore, severe digestive problems and dizziness were described in a high proportion of individuals at both 3,500 and 4,250 m.

CONCLUSIONS

The prevalence of AMS in this study is similar to that reported elsewhere at equivalent altitudes.