Antivenom effect on lymphatic absorption and pharmacokinetics of coral snake venom using a large animal model.

Context: Historically, administration and dosing of antivenom (AV) have been guided primarily by physician judgment because of incomplete understanding of the envenomation process. As demonstrated previously, lymphatic absorption plays a major role in the availability and pharmacokinetics (PK) of coral snake venom injected subcutaneously, which suggests that absorption from subcutaneous tissue is the limiting step for venom bioavailability, supporting the notion that the bite site is an ongoing venom depot. This feature may underlie the recurrence phenomena reported in viperid envenomation that appear to result from a mismatch between venom and AV PK. The role of lymphatic absorption in neutralization of venom by AV administered intravenously remains unclear. Methods: The effect of AV on systemic bioavailability and neutralization of Micrurus fulvius venom was assessed using a central lymph-cannulated sheep model. Venom was administered by subcutaneous injection in eight sheep, four with and four without thoracic duct cannulation and drainage. Two hours after venom injection, AV was administered intravenously. Venom and AV concentrations in serum and lymph were determined by ELISA assay from samples collected over a 6-h period and in tissues harvested post-mortem. Results: After AV injection, venom levels in serum fell immediately to undetectable with a subsequent increase in concentration attributable to non-toxic venom proteins. In lymph, AV became detectable 6 min after treatment; venom levels dropped concurrently but remained detectable 4 h later. Post-mortem samples from the venom injection site confirmed the presence of venom near the point of injection. Neither venom nor AV was detected at significant concentrations in major organs or contralateral skin. Conclusions: Intravenous AV immediately neutralizes venom in the bloodstream and can extravasate to neutralize venom absorbed by lymph but this neutralization seems to be slow and incomplete. Residual venom in the inoculation site demonstrates that this site functions as a depot where it is not neutralized by AV, which allows the venom to remain active with slow delivery to the bloodstream for ongoing systemic distribution.

Mental health, positive affectivity and wellbeing in prison: a comparative study between young and older prisoners.

OBJECTIVES: To explore sociodemographic, psychological and psychopathological characteristics, as well as to evaluate the behaviour in an inmate sample. MATERIALS AND METHODS: There is a total sample of 182 young and elderly inmates of the Madrid III Prison. The investigation has been carried out with a battery of self-report psychological questionnaires and objective measurements obtained through the prison files. Comparisons of means were made to see if there are significant differences between the two groups (young and elderly inmates) in the variables analysed. RESULTS: The analysis shows that there are no significant differences in wellbeing between young and elderly inmates. However, young people have higher levels of psychological distress, more presence of negative emotions and have a more maladjusted behaviour in prison (they consume more cannabis and have more disciplinary records). Older people better regulate their emotions, adopt better the perspectives of others, showing themselves to be friendlier. CONCLUSIONS: The elderly inmates in prison, compared with the youngest, have a better psychological adjustment, more internal resources and a better adaptation to the prison environment despite of no differences in related variables such as time in prison.

Salud mental, afectividad positiva y bienestar en prisión: un estudio comparativo entre jóvenes y mayores presos / Mental health, positive affectivity and wellbeing in prison: a comparative study between young and older prisoners

Objetivos: Explorar las características sociodemográficas, psicológicas y psicopatológicas, así como evaluar la conducta de una muestra de internos. Materiales y métodos: Se cuenta con una muestra total, entre jóvenes y mayores, de 182 internos del Centro Penitenciario Madrid III. La investigación se ha llevado a cabo con una batería de cuestionarios psicológicos de autoinforme y medidas objetivas obtenidas a través de los expedientes penitenciarios. Se realizaron comparaciones de las medias para ver si existen diferencias significativas entre los dos grupos (jóvenes y mayores) en las variables analizadas. Resultados: El análisis muestra que no existen diferencias significativas en los niveles de bienestar de jóvenes y mayores. Sin embargo, los jóvenes muestran grados más elevados de malestar psicológico, presentan más emociones negativas y una conducta más desadaptada en la prisión (consumen más cannabis y tienen más expedientes disciplinarios). Las personas mayores regulan mejor sus emociones, adoptan mejor las perspectivas de otros, mostrándose además más amables. Conclusiones: Las personas mayores que están en prisión, comparados con los más jóvenes, presentan un mejor ajuste psicológico, más recursos internos y un mejor nivel de adaptación al medio penitenciario, a pesar de no existir diferencias en variables asociadas como, por ejemplo, el tiempo en prisión

Objective: To explore socio-demographic, psychological and psychopathological characteristics, as well as to evaluate behaviour in a sample of inmates. Material and methods: A sample of 182 young and elderly inmates of the Madrid III Prison was used. The research was carried out with a battery of self-report psychological questionnaires and objective measurements obtained through the prison files. Comparisons of means were made to see if there are significant differences between the two groups (young and elderly inmates) in the variables analysed. Results: The analysis shows that there are no significant differences in wellbeing between young and elderly inmates. However, young people have higher levels of psychological distress, more presence of negative emotions and have a more maladjusted behaviour in prison (they consume more cannabis and have more disciplinary proceedings registered). Older people regulate their emotions better, adopt the perspectives of others more effectively and show themselves to be friendlier. Conclusions: The elderly inmates in prison, compared with the youngest ones, have better psychological adjustment, more internal resources and are better adapted to the prison environment despite there being no differences in related variables such as time in prison

Molecular epidemiology and antimicrobial resistance of Clostridium difficile in a national geriatric hospital in Costa Rica.

BACKGROUND: The epidemiology of Clostridium difficile infections (CDI) is changing rapidly worldwide; knowledge on the genotypes of C. difficile circulating in specialized geriatric hospitals and their resistance to antibiotics is scarce or non-existent. METHODS: Prospective study of the molecular epidemiology of CDI, conducted in a national geriatric hospital in Costa Rica for a period of 11 months. RESULTS: The study patients exhibited a diverse range of comorbidities, but none were associated with CDI. Polyclonality, including three new ribotypes, and a high level of resistance to antibiotics were determined by analysing the 32 isolates obtained in these cases. Despite the diversity in strains observed, the most frequent types were NAP6/RT002 and NAP2/RT001. NAP9/RT017 was associated with community acquisition. Nineteen types of antimicrobials were used before the onset of diarrhoea in the patients; no particular genotype was associated with the onset of infection or severity. CONCLUSION: Based on the abundance of strain types observed and their resistance to antibiotics in this geriatric hospital, these results contribute to a better overall understanding of the epidemiology of CDI worldwide, and to surveillance programmes targeting geriatric populations.

Síndrome de Parsonage-Turner durante el tratamiento de la enfermedad de Castleman multicéntrica asociada a VIH y herpes humano 8 / Parsonage-Turner syndrome during the treatment of HIV/HHV8-related multicentric Castleman disease

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Lymphatic route of transport and pharmacokinetics of Micrurus fulvius (coral snake) venom in sheep.

The contribution of the lymphatic system to the absorption and systemic bioavailability of Micrurus fulvius venom after subcutaneous (SC) administration was assessed using a central lymph-cannulated sheep model. Micrurus fulvius venom was administered either by intravenous bolus (IV) or subcutaneous injection (SC) in 12 sheep with and without thoracic duct cannulation and drainage. Venom concentration in serum and lymph was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) in samples collected over a 6-hour period and in tissues harvested at the end of the experiment. Pharmacokinetic parameters were determined by a non-compartmental analysis. In the lymphatic cannulated group, over the 6 hours after the venom was administered, 69% of administered dose was accounted for in blood (45%) and lymph (25%). Negligible levels of venom were detected in organs and urine implying that the steady state observed after SC administration is maintained by a slow absorption process. Comparison of kinetics of the thoracic duct cannulated and non-cannulated groups showed that lymphatic absorption contributed in an important way to maintenance of this steady state. These results show that the limiting process in the pharmacokinetics of Micrurus fulvius venom following SC administration is absorption, and that the lymphatic system plays a key role in this process.

Nanoindentation-induced phase transformations in silicon at elevated temperatures.

The nanoindentation-induced phase transformation behavior of silicon at elevated temperatures (25-150 degrees C) has been studied. Nucleation of Si-III/Si-XII on unloading is enhanced with increasing temperature and at the highest temperatures in an amorphous Si matrix, occurs in a continuous fashion without a pop-out event. Interestingly, for slow unloading at the highest temperatures, formation of Si-III/Si-XII in a crystalline Si matrix was not observed. Elevated temperatures enhance the nucleation of Si-III and Si-XII during unloading but the final composition of the phase transformed zone is also dependent on the thermal stability of the phases in their respective matrices.

Acute and chronic graft-versus-host disease after allogeneic peripheral-blood stem-cell and bone marrow transplantation: a meta-analysis.

PURPOSE: Controversy exists as to whether the incidence of graft-versus-host disease (GVHD) is increased after peripheral-blood stem-cell transplantation (PBSCT) when compared with bone marrow transplantation (BMT). We performed a meta-analysis of all trials comparing the incidence of acute and chronic GVHD after PBSCT and BMT reported as of June, 2000. Secondary analyses examined relapse rates after the two procedures. METHODS: An extensive MEDLINE search of the literature was undertaken. Primary authors were contacted for clarification and completion of missing information. A review of cited references was also undertaken. Sixteen studies (five randomized controlled trials and 11 cohort studies) were included in this analysis. Data was extracted by two pairs of reviewers and analyzed for the outcomes of interest. Meta-analyses, regression analyses, and assessments of publication bias were performed. RESULTS: Using a random effects model, the pooled relative risk (RR) for acute GVHD after PBSCT was 1.16 (95% confidence interval [CI], 1.04 to 1.28; P=.006) when compared with traditional BMT. The pooled RR for chronic GVHD after PBSCT was 1.53 (95% CI, 1.25 to 1.88; P <.001) when compared with BMT. The RR of developing clinically extensive chronic GVHD was 1.66 (95% CI, 1.35 to 2.05; P <.001). The excess risk of chronic GVHD was explained by differences in the T-cell dose delivered with the graft in a meta-regression model that did not reach statistical significance. There was a trend towards a decrease in the rate of relapse after PBSCT (RR = 0.81; 95% CI, 0.62 to 1.05). CONCLUSION: Both acute and chronic GVHD are more common after PBSCT than BMT, and this may be associated with lower rates of malignant relapse. The magnitude of the transfused T-cell load may explain the differences in chronic GVHD risk.

Outcomes following extracranial carotid artery stenting in high-risk patients.

BACKGROUND: Carotid artery angioplasty and stenting has become a viable alternative to carotid endarterectomy (CEA), especially for patients considered at high risk for post-operative complications. This study investigated the feasibility, safety and long-term outcome of carotid artery stenting (CAS) in high-risk patients. METHODS: From July 1995 to November 2000, sixty-two consecutive patients considered to be at high risk for post-operative complications of CEA were followed prospectively after undergoing extracranial CAS procedures. RESULTS: Sixty-two patients [37 men (60%) and 25 women (40%)] underwent a total of 69 CAS procedures. The mean age was 67 +/- 9 years (range, 32-89 years). Comorbid conditions included hypertension in 95% and severe coronary artery disease in 58%. Sixteen patients (26%) had a previous ipsilateral CEA, twenty-one percent had a history of neck radiation and 32% had a history of significant contralateral carotid artery disease. Fifty-two patients (84%) were symptomatic. All 69 CAS procedures were technically successful. The major post-operative complications were two minor strokes (2.8%), one major stroke (1.4%) and one fatal major stroke (1.4%). The mean length of follow-up was 17 months (range, 4 months to 5.6 years). Two patients (2.8%) have suffered ipsilateral neurologic events following CAS. Long-term follow-up revealed restenosis at 6 months in 4 patients (5.7%). CONCLUSIONS: Carotid artery angioplasty and stenting is safe and feasible. This procedure produces satisfactory outcomes in patients who are at high risk for post-operative complications of CEA.

Increased prevalence of significant tricuspid regurgitation in patients with transvenous pacemakers leads.

Transvenous pacemaker leads are associated with an increased prevalence of tricuspid regurgitation. This hemodynamic derangement should be considered as part of the clinical cost and complications of permanent pacemaker implantation.

[Interpretation of negative clinical trials]. / La interpretación de los ensayos clínicos negativos.

Randomized clinical trials without statistically significant differences between treatment groups may provide useful information for clinicians. However, negative trials must be interpreted cautiously, since the absence of evidence of treatment effect is not the same as evidence of absence of treatment effect. Before the reader of a negative article can conclude that one intervention was not better than the other, the potential causes of a negative study should be explored. The objective of this manuscript is to critically describe some of the most common methodological problems that can explain the lack of difference between studied groups in randomized clinical trials.

Thyrotoxic periodic paralysis in a black man.

We report a case of thyrotoxic hypokalemic periodic paralysis occurring in a black man. This previously healthy 41-year-old man had a 3-year history of recurrent paroxysmal episodes of paresis in the upper and lower extremities proximally, often occurring after heavy exercise. The patient had no history of hyperthyroidism, nor family history of periodic paralysis. This case reveals a particularly rare characteristic of this disorder in which periodic paralysis is the presenting symptom of hyperthyroidism. This condition has been reported most commonly among Asians and is extremely rare in black men, only five cases having been described during the past 30 years.

Conocimiento y actitudes de las madres en relación a las infecciones respiratorias agudas (IRA) de sus hijos / Know and acttitud of the mother in relation of the acute respiratory infections (ARI) of the sons

Se presentan los conocimientos y actitudes de una muestra de madres que acudió al Hospital de niños de Santo Domingo, en demanda de atención médica para sus hijos enfermos de infección Respiratoria Aguda, encontrándose una falta de información y conocimientos sobre las IRA en una proporción significativamente importante (p<0.001) de esas madres. Se destaca la tardanza en la búsqueda de asistencia médica, el tratamiento casero y el cumplimiento de la terapia como factores que agravan la enfermedad. Por último, se resalta el tabaquismo amplificado por la contaminación doméstica, por la promiscuidad y la exigüedad de las habitaciones como factores coadyuvantes de las IRA; puntualizándose el desconocimiento materno del rol nocivo que estos factores representan.