The Barnum effect in couples: effects of intimacy, involvement, and sex on acceptance of generalized personality feedback

The study assessed the impact of test feedback about one partner on both members of male-female couples. Twenty-four males and 24 females ("participants") took an inkblot test and received a standard personality interpretation-purportedly derived from the test-in the presence of a partner (the "observer"). Half the pairs were strangers; the other half defined themselves as intimate friends. Intimate couples rated the feedback as more accurate, remembered more of the feedback, reported more faith in psychological tests, and rated experimenter skill higher than did strangers. Male participants rated the feedback as more accurate than did male observers. Males may be more receptive of feedback in couples when they themselves have taken the test.     

Aspiration of osteoprogenitor cells for augmenting spinal fusion: comparison of progenitor cell concentrations from the vertebral body and iliac crest

BACKGROUND: Successful arthrodesis in challenging clinical scenarios is facilitated when the site is augmented with autograft bone. The iliac crest has long been the preferred source of autograft material, but graft harvest is associated with frequent complications and pain. Connective tissue progenitor cells aspirated from the iliac crest and concentrated with allograft matrix and demineralized bone matrix provide a promising alternative to traditional autograft harvest. The vertebral body, an even larger reservoir of myeloproliferative cells, should provide progenitor cell concentrations similar to those of the iliac crest. METHODS: Twenty-one adults (eleven men and ten women with a mean age of 59 +/- 14 years) undergoing posterior lumbar arthrodesis and pedicle screw instrumentation underwent transpedicular aspiration of connective tissue progenitor cells. Aspirates were obtained from two depths within the vertebral body and were quantified relative to matched, bilateral aspirates from the iliac crest that were obtained from the same patient at the same time. Histochemical analysis was used to determine the prevalence of vertebral progenitor cells relative to the depth of aspiration, the vertebral level, age, and gender, as compared with the iliac crest standard. The cell count, progenitor cell concentration (cells/cc marrow), and progenitor cell prevalence (cells/million cells) were calculated. RESULTS: Aspirates of vertebral marrow demonstrated comparable or greater concentrations of progenitor cells compared with matched controls from the iliac crest. Progenitor cell concentrations were consistently higher than matched controls from the iliac crest (p = 0.05). The concentration of osteogenic progenitor cells was, on the average, 71% higher in the vertebral aspirates than in the paired iliac crest samples (p = 0.05). With the numbers available, there were no significant differences relative to vertebral body level, the side aspirated, the depth of aspiration, or gender. An age-related decline in cellularity was suggested for the iliac crest aspirates. CONCLUSIONS: The vertebral body is a suitable site for aspiration of bone marrow for graft augmentation during spinal arthrodesis.     

Interfering vaccine: a novel antiviral that converts a potentially virulent infection into one that is subclinical and immunizing

Infection with human influenza A virus can reach cataclysmic levels, with 40 or more million deaths arising from the 1918 pandemic. Preventative and therapeutic measures have improved since that time, but new approaches are needed. Here, we describe one such new approach--the interfering vaccine, which has two activities--it prophylactically prevents influenza, and at the same time converts an otherwise lethal infection into one that is avirulent and immunizing. Mice treated in this way develop a solid immunity that protects them against a subsequent challenge with homologous virus, and to a lesser extent from challenge with heterologous influenza A viruses. The interfering vaccine comprises non-infectious, defective interfering (DI) influenza A virus. Prophylaxis is mediated directly by DI RNA, and results from interference with the replication of the infecting virus. However, interference is incomplete, and there is sufficient wild-type virus multiplication to stimulate a virus-specific natural immunity. As the replication mechanism is common to all influenza A viruses, an interfering vaccine should protect from, and permit immunity to be developed to all influenza A viruses. Indeed, we demonstrate protection against two viruses with antigenically unrelated HA and NA proteins. Thus an interfering vaccine, unlike the conventional vaccine, is independent of the antigenicity of the infecting virus. In principle, interfering vaccines derived from other virus systems could also be developed.     

An animal model of halothane hepatotoxicity: roles of enzyme induction and hypoxia.

Exposure of phenobarbital-pretreated male Sprague-Dawley rats to halothane, 1 per cent, for two hours under conditions of hypoxia (FIO2 0.14) resulted in extensive centrilobular necrosis within 24 hours. Accompanying the morphologic damage were an increase in serum glutamic pyruvic transminase (SGPT) and a decrease in hepatic microsomal cytochrmoe P-450. Glutathione levels in the liver were unchanged. Phenobarbital-pretreated rats anesthetized with halothane, 1 per cent, at FIO2 0.21 had only minor morphologic changes at 24 hours. Hepatic injury was not apparent in any non-phenobarbital-induced rat or in any induced animal exposed to ether at FIO2 0.10 or to halothane at FIO2 0.99. There was a 2.6-fold increase in the 24-hour urinary excretion of fluoride in those rats in which extensive centrilobular necrosis developed. The in-vivo covalent binding to lipids of 14C from 14C-halothane also was increased markedly when 14C-halothane was administered intraperitoneally to phenobarbital-induced rats maintained hypoxic (FIO2 0.14) for two hours. These results support the authors' hypothesis that halothane is metabolized to hepatotoxic intermediates by a reductive or non-oxygen-dependent cytochrome P-450-dependent pathway. This animal model of halothane-induced hepatotoxicity may be clinically relevant. A decrease in hepatic blood flow during halothane anesthesia may decrease the PO2 available to hepatocytes and thus direct the metabolism of halothane along its reductive, hepatotoxic pathway.     

The immunohistology of follicle lysis in lymph node biopsies from homosexual men

Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.     

Dural infolding during C1-2 myelography

Inward buckling of the dura at C1-2 may occasionally occur with hyperextension of the neck and can result in a difficult or unsuccessful puncture when the posterior lateral C1-2 approach is used for cervical myelography. In this circumstance, placement of the head in a neutral or slightly flexed position may widen the posterior subarachnoid space and facilitate the needle puncture.     

Characteristics of pedicle screw loading. Effect of sagittal insertion angle on intrapedicular bending moments.

STUDY DESIGN: A bending analysis of pedicle screws inserted into vertebral body analogues. Intravertebral and intrapedicular pedicle screw bending moments were studied as a function of sagittal insertion angle. OBJECTIVES: To determine how the pedicle screw bending moment is affected by changes in the insertion angle. SUMMARY OF BACKGROUND DATA: There is a significant incidence of failure when pedicle screws are used to instrument unstable spinal segments. Extrinsic factors that affect screw bending failure have been poorly characterized. Previous work has demonstrated that intrapedicular pedicle screw bending moments are significantly affected by the sagittal location and depth of pedicle screw placement. METHODS: Pedicle screw transducers were inserted in analogue vertebrae at one of three orientations: 7 degrees cephalad (toward the superior endplate), 7 degrees caudal (toward the inferior endplate), or parallel to the superior endplate (control). An axial load was applied to the superior endplate of the vertebra, and screw bending moments were recorded directly from the transducers. RESULTS: Screws angled 7 degrees cephalad developed significantly greater mean intrapedicular bending moments compared with screws inserted caudal or control screws. There was no significant difference in bending moments realized within the vertebral body for the three screw positions. CONCLUSIONS: Angulating pedicle screws toward the superior endplate increased bending moments within the pedicle. If attention to optimal screw insertion technique can reduce bending moments and potential for screw failure without increasing morbidity, surgical risk, or operative time, then proper insertion technique takes on new importance.