Changes in thymic export of L-selectin+ γδ and αβ T cells during fetal and postnatal development

We have used the technique of in situ intrathymic injection of fluorescein isothiocyanate to examine L-selectin expression on γδ and αβ T cells immediately after emigrating from the thymus of fetal and postnatal animals. We found that the percentage of L-selectin⁺ thymocytes exported per day decreased by half after birth and that the export of T cells from the thymus does not rely on expression of the peripheral lymph node homing receptor, L-selectin. Analysis of L-selectin on emigrant and mature T cell subsets revealed a remarkable heterogeneity of expression, both in terms of the numbers of cells expressing this molecule as well as the level of expression. γδ T cells, reportedly not having a propensity for homing to lymph nodes, not only contained the highest proportion of L-selectin⁺ cells, but also expressed far more of this molecule than either CD4⁺CD8^? or CD4^?CD8⁺ αβ T cells. Furthermore, those emigrant T cells expressing L-selectin are somewhat immature in their expression of this molecule. Subsequent maturation resulted in up-regulation of L-selectin on mature peripheral blood T cells, maturation that was clearly independent of extrinsic antigen. This antigen-independent post-thymic maturation appeared to occur as part of the normal progression from immature thymocyte to mature peripheral T cell in both fetal and postnatal animals.     

Immunological studies in patients with juvenile-onset myasthenia gravis and in their relatives

Fifty-four patients who developed myasthenia before the age of 20 had an increased incidence of autoantibodies similar to that in adult-onset myasthenics, except that there was no significant increase of striated muscle antibodies. The increase in thyroid antibodies was associated with an increase of thyroid disease.

Their 150 relatives showed a significant increase in thyroid antibodies, in thyroid disease, and a non-significant increase in the five other autoantibodies studied. There was aggregation of thyroid antibodies in some families.

Two patients and one relative were deficient for immunoglobulins (one patient and one father for IgA and one patient for IgM).

These familial immunological abnormalities, which are more marked in the families of patients with juvenile-onset myasthenia than in the families of adult-onset patients, point to fundamental genetic immunopathogenesis of the disease.

     

Equol and other compounds from bovine urine as monoamine oxidase inhibitors

Summary Equol, its methylated derivative, and a carbazole, all isolated from bovine urine, are relatively potent inhibitors of monoamine oxidase with IC₅₀ values of 158, 28, and 16M respectively (using 83M tyramine as substrate). The probable dietary origin of these compounds suggests that natural monoamine oxidase inhibitors may be more widespread than had previously been suspected.     

Perioperative transfusions associated with colorectal cancer surgery : Clinical judgment versus the hematocrit

We prospectively studied 123 patients with colorectal cancer in order to identify determinants of perioperative blood transfusions and unnecessary transfusions. Transfusions were considered unnecessary if the preoperative hematocrit reading exceeded 36% or the discharge hematocrit level exceeded 33%. Age, sex, admission hematocrit reading, operative procedure, specimen length, duration of surgery, estimated blood loss, tumor size, tumor differentiation, nodal status, Dukes' staging, and attending surgeon were evaluated in relation to perioperative blood transfusion using stepwise logistic regression. Fifty-one (41%) of the 123 patients in the study were transfused and 35 patients (28%) received at least 1 unnecessary unit of blood. Advanced age, low admission hematocrit reading, high estimated operative blood loss, prolonged procedures, and lengthy specimens were significantly related to the administration of blood. Excessive intraoperative transfusions and the practice of administering blood in pairs of units accounted for the unnecessary transfusions. This study indicates that factors that influence clinical judgment and thereby the decision to transfuse a patient are not accurate indicators of when blood should be given. Greater use of pre-transfusion hematocrit testing, especially in the operating room and before transfusing a second unit of blood, will dramatically reduce blood usage in elective colorectal cancer surgery.

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Resumen Hemos estudiado en forma prospectiva 123 pacientes con cáncer colorrectal con el objeto de identificar factores determinantes de transfusiones sanguíneas perioperatorias y de transfusiones innecesarias. Se consideró que las transfusiones eran innecesarias si el hematocrito preoperatorio excedía 36% o si el hematocrito de egreso excedía 33%. La edad y sexo, el hematocrito de admisión, el tipo de procedimiento operatorio, la longitud del especimen resecado, la duración de la operación, la magnitud estimada de la pérdida de sangre, el tamaño del tumor, el grado de la diferenciación del tumor, el estado de los ganglios, la clasificación Dukes del tumor y el cirujano, fueron valorados en relación con el volumen de transfusión perioperatoria utilizando el método de regresión logística escalonada. Cincuenta y uno (41%) de los 123 pacientes fueron transfundidos y 35 (28%) recibieron por lo menos una unidad de sangre innecesaria. La edad avanzada, un hematocrito bajo en el momento de la admisión, la escimación de una alta pérdida de sangre, los procedimientos prolongados y los especimenes de gran longitud aparecieron como factores significativamente relacionados con la administracion de sangre. Las transfusiones intraoperatorias excesivas y la práctica de administrar sangre en pares de unidades fueron responsables de las transfusiones innecesarias. Este estudio indica que los factores que influencian el juicio clínico, y por consiguiente la decisión de transfundir a un paciente, no son indicadores precisos de cuando se debe administrar sangre. Una mayor utilización del hematocrito pretransfusión, especialmente dentro de la sala de operaciones y antes de transfundir una segunda unidad de sangre, logrará disminuir en forma dramática el uso de sangre en cirugía electiva para cáncer colorrectal.

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Résumé Les auteurs se sont livrés à une étude prospective de 123 malades atteints de cancer colorectal dans le but d'identifier les facteurs qui ont été à l'origine de transfusions pré-, per-, et postopératoires et de transfusions inutiles. Les transfusions ont été considérées comme inutiles lorsque l'hématocrite préopératoire dépassait 36 pour cent ou qu'il excédait 33 pour cent au moment de la sortie de l'opéré. Pour apprécier la valeur de la transfusion périopératorie ont été pris en compte les divers facteurs suivants : l'âge, le sexe, le taux de l'hématocrite à l'admission, le type de l'intervention, la longueur du spécimen, la durée de l'opération, la quantité de sang perdu, la taille de la tumeur, le degré de différenciation du cancer, l'état des ganglions, le stade évolutif (classification de Dukes), la qualification du chirurgien. Cinquante et un des malades (41%) furent transfusés et 35 parmi eux (28%) reçurent inutilement au moins une unité de sang. L'ae avancé de l'opéré, le taux bas de l'hématocrite à l'admission, la perte importante de sang au cours de l'intervention, la longue durée de l'opération, l'importance de la pièce opératoire réséquée furent en rapport de manière significative avec l'administration de sang. Les transfusions inutiles furent le fait de l'administration excessive de sang au cours de l'opération ou de l'emploi d'unités doubles de sang. Cette étude indique que les facteurs cliniques ne constituent pas des éléments de valeur pour déterminer l'indication de la transfusion de sang. C'est le taux de l'hématocrite avant et au cours de l'intervention qu'il faut prendre en compte. L'observation de cette règle est appelée à réduire considérablement l'emploi du sang au cours de la chirurgie colorectale élective.

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Supported by the Frieda and George Zinberg Foundation and NCI-NIH grant 1 RO1-CA-35558-01.     

Establishing the minimal clinically important difference of the EQ-5D-3L in older adults with a history of falls

Quality of Life Research - Establish the minimal clinically important difference (MCID) of a health-related quality of life (HRQoL) measure—the EuroQol EQ-5 Dimensions-3 Level...     

Employment Consequences of COVID-19 for People with Disabilities and Employers

Journal of Occupational Rehabilitation - Purpose The COVID-19 pandemic has disproportionately affected the lives of people with disabilities (PWD). How the pandemic affects the employment of PWD...     

Group B Streptococcus Screening Guidelines in Pregnancy: A Critical Review of Compliance

Maternal and Child Health Journal - Colonization with Group B Streptococcus in pregnancy is a major risk factor for neonatal infection. Universal screening for maternal streptococcal colonization...     

Job Accommodations,Return to Work and Job Retention of People with Physical Disabilities: A Systematic Review

Journal of Occupational Rehabilitation - Purpose We aimed to identify job accommodations that help persons with physical disabilities maintain or return to work and explore the barriers and...     

Development of a Programme Theory for Early Intervention Vocational Rehabilitation: A Realist Literature Review

Journal of Occupational Rehabilitation - Purpose Little is currently known about how early intervention vocational rehabilitation (EIVR) works for people with newly acquired neurological conditions...