Thirty-minute continuous sitting force measurements with different support surfaces in the spinal cord injured and able-bodied

Able-bodied, paraplegic, and quadriplegic subjects sat for 30-minute intervals on various surfaces in a wheelchair with a forceplate mounted on the seat in order to determine factors that could contribute to the formation of decubitus ulcers. All three groups of subjects sat on ROHO and Jay cushions; in addition to sitting on the two cushions, the able-bodied subjects sat on a hard surface. Factors studied were: normal and shear seat forces, the location of the center of mass, and armrest force. The forceplate was under the cushions; therefore, the values reflect average forces over the buttocks and posterior thighs. These factors were compared between disability levels as well as between surface types. Larger, normal, and forward shear forces and a more anterior position of the center of mass were observed with the ROHO cushion. More frequent and larger lateral weight shifts occurred with the Jay cushion. The armrests tended to support from 5 percent of the body weight for quadriplegics to 9 percent for paraplegics. The results suggest that armrests reduce seat forces by carrying some of the body weight.

The causes and control of anxiety

The 20th century has been described as the age of anxiety. Many have claimed that the pressures of a modern technological and competitive society are too great. Anxiety is a normal part of reaction to threats created by life situations especially when control is low. Some people perpetuate constant anxiety by oversensitivity to environmental events. Anxiety can reduce daily efficiency and become self-enhancing. Biological mechanisms may also sustain anxiety further. Treatments include addressing both the cognitive and the biological aspects of the state. Training people to cope with life and to find forms of control may be the most beneficial in the long term.

Postmarketing surveillance: accuracy of patient drug attribution judgments

Data from two samples of ambulatory patients participating in a postmarketing surveillance study, one receiving antibiotics and another receiving tricyclic antidepressant agents, are presented, indicating that patients appear to be capable of correctly discriminating probable adverse drug reactions from other adverse clinical events. However, attribution accuracy depended both on the surveillance method and on how reports of the adverse clinical events were obtained. Discrimination was better when patients were reporting adverse clinical events spontaneously than when the interviewer probed for recall in a systematic inquiry. Discrimination was also better when the adverse clinical events were obtained from a staff-initiated surveillance method than from a self-monitoring, patient-initiated telephone-reporting method--probably because the latter method generates an excessively strong tendency to report mainly those adverse clinical events suspected of being drug related.

Cognitive impairments in abstinent alcoholics

Impaired cognitive functioning in alcoholics is widespread during the first months of detoxification. Between half and two thirds of abstinent alcoholics exhibit cognitive impairments during this period, with residual deficits persisting for years after detoxification in some patients. The most severe deficits have been observed in visuospatial abilities, perceptual-motor integration, abstract reasoning, and new learning. The most significant predictors of cognitive dysfunction in persons recovering from alcoholism are the time elapsed since the last drink and the person's age. Surprisingly, the pattern and duration of a patient's alcohol abuse are relatively weak determinants of neuropsychological impairment during abstinence. Research investigating the hypothesis that cognitive impairments may be related to alcoholic persons resuming drinking has yielded mixed results, but a higher level of neuropsychological functioning is associated with increased rates of completing treatment programs and with greater success in the work environment after discharge from treatment. The possibility of cognitive limitations should be taken into account in planning treatment programs for alcoholism.

Evaluation of flurbiprofen-exposed irises to acetylcholine anterior chamber irrigation

Flurbiprofen (Ocufen), an antiprostaglandin, has been introduced into cataract surgery. It is used to prevent intraoperative miosis by blocking inflammatory mediator formation. Ocufen has been noted to diminish the controlled miosis produced by using acetylcholine in the operative period. This study evaluated the pupillary response to acetylcholine after it had been exposed to Ocufen. This was done using a control versus a study eye in 16 rabbits dilated with phenylephrine hydrochloride and cyclopentolate hydrochloride. The pupil diameters were measured at baseline, then the rabbits' anterior chambers were irrigated with an acetylcholine solution. The resultant pupillary diameters were measured at one and five minutes. At five minutes post-irrigation there was a statistically significant greater constriction in the control group than in the Ocufen group. This implies that Ocufen dampens the iris musculature's response to acetylcholine.

Central venous access devices in children

Central venous access devices are used with increasing frequency in children with chronic illnesses that require long-term parenteral treatment. Nurses are often responsible for taking care of the device and teaching the family home maintenance.

Sitting forces and wheelchair mechanics

The effects of back angle and leg height on sitting forces in a wheelchair were studied, using a force plate mounted on a wheelchair seat. Readings of both normal force (perpendicular to the seat) and shear force were measured while the chair's back angle and footrest height were changed. Pressure under the ischial tuberosities was also measured during the footrest height adjustments. Five normal subjects sat directly on the plate as well as upon ROHO and Jay cushions placed on the force plate. Returning the back to the upright position after a recline caused the normal force (+/- SD) to increase 5.4 +/- 2.5, 9.5 +/- 4.0, and 10.0 +/- 2.3 kg for the hard surface, Jay cushion, and ROHO cushion respectively, while shear at the plate increased to 5.1 +/- 2.2, 11.6 +/- 2.6, and 12.3 +/- 2.7 kg for the hard surface, Jay cushion, and ROHO cushion respectively. Leaning forward (away from the back) caused all the forces to return to measurements close to the starting values. The results suggest that the wheelchair user should momentarily lean forward after a recline to reduce undesired forces. If a cushion with firm thigh support is used, ischial tuberosity pressure can be reduced by lowering the leg height as much as possible, which causes a levering action by lifting the pelvis.

Virtual environments and interactivity: windows to the future

I really apologize. I promised everyone I would come out wearing the data suit, but it just slipped my mind and I never got around to it. Actually Marvin Minsky was saying that the thing to do would be to come out with nothing on because that would be the perfect interface to the computer. So I kind of shunned the whole thing off at that point.We just heard Nicholas Negroponte ask us -- "how do we communicate with computers?" Well, that's why this panel is here today. We'll be discussing virtual environments and interactivity with some of the people who have been doing a lot of work in this field. I was interviewing a lot of people last night at the parties about virtual environments and I realized that everyone has their own idea of what their virtual environment will be. Some want to interact more, others less. Some want little people running around on the screen bringing them all sorts of messages or images. We'll be hearing about a lot of different types of interactivity on our panel today.I'd like to point out that Margaret's slide should also include the MIT Media Lab as well as UNC.I'm going to show some tapes and do some talking later on so I'd like start of by introducing Jaron Lanier. He's the guy with the dreadlocks you've seen at the Silicon Graphics booth. He has an amazing collection of musical instruments from all over the world and when he plays them, he transports you to other times and other places. He's a designer of programming languages and he started VPL, the company that brought you the glove, Jaron.

Developmental expression of the amyloid precursor protein, growth-associated protein 43, and somatostatin in normal and trisomy 16 mice

The expression during development of 3 genes located on mouse chromosome 16 (MMU 16) which are implicated in neurobiological processes was examined by blot hybridization beginning at early gestational ages in the mouse. The 3 genes, amyloid precursor protein (App), preprosomatostatin (Smst), and growth-associated protein 43 (Gap43), exhibited distinct profiles of expression. App expression increased steadily throughout fetal and postnatal development. Smst expression peaked during the third postnatal week, then reached a plateau at a slightly lower level in adults, and Gap43 expression was highest in the early postnatal period, declining in adults to levels below those seen at the earliest timepoints examined. Smst message levels exhibited a 1.5-fold increase in the brains of trisomy 16 (Ts16) mice as compared to normal littermates on day 15 of gestation, while Gap43 and App message levels were elevated approximately 2-fold.

Asparagine-linked glycosylation of the scrapie and cellular prion proteins

Post-translational modification of the scrapie prion protein (PrP) is thought to account for the unusual features of this protein. Molecular cloning of a PrP cDNA identified two potential Asn-linked glycosylation sites. Both the scrapie (PrPSc) and cellular (PrPC) isoforms were susceptible to digestion by peptide N-glycosidase F (PNGase F) but resistant to endoglycosidase H as measured by migration in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. PNGase F digestion of PrPC yielded two proteins of Mr26K and 28K; however, the 26-k species was only a minor component. In contrast, PNGase F digestion of PrPSc yielded equimolar amounts of two proteins of Mr26K and 28K. The significance of this altered stoichiometry between the 26- and 28-kDa deglycosylated forms of PrP during scrapie infection remains to be established. Both isoforms as well as PrP 27-30, which is produced by limited proteolysis of PrPSc, exhibited a reduced number of charge isomers after PNGase F digestion. The molecular weight of PrP 27-30 was reduced from 27K-30K by PNGase F digestion to 20K-22K while anhydrous hydrogen fluoride or trifluoromethanesulfonic acid treatment reduced the molecular weight to 19K-21K and 20K-22K, respectively. Denatured PrP 27-30 was radioiodinated and then assessed for its binding to lectin columns. PrP 27-30 was bound to wheat germ agglutinin (WGA) or lentil lectins and eluted with N-acetylglucosamine or alpha-methyl-mannoside, respectively. Digestion of PrP 27-30 with sialidase prevented its binding to WGA but enhanced its binding to Ricinus communis lectin. These findings argue that PrP 27-30 probably possesses Asn-linked, complex oligosaccharides with terminal sialic acids, penultimate galactoses, and fucose residues attached to the innermost N-acetyl-glucosamine. Whether differences in Asn-linked oligosaccharide structure between PrPC and PrPSc exist and are responsible for the distinct properties displayed by these two isoforms remain to be established.

Testicular feminization in a cat

Testicular feminization, caused by an inherited defect of the androgen receptor, was diagnosed in a domestic cat. Individuals affected with this syndrome are genetic males that have testes but fail to undergo masculinization because the internal and external genitalia cannot respond to androgens. The affected cat had the external appearance of a sexually normal female, but during surgery for ovariohysterectomy, only 2 abdominal gonads were found. Müllerian (uterus) or wolffian (epididymides) derivatives were not present. Only testicular tissue was found in histologic sections of the gonad. A normal male chromosome constitution (38,XY) was found in karyotypes prepared from lymphocyte cultures. High affinity binding of dihydrotestosterone was undetectable in fibroblasts cultured from genital skin of the affected cat, indicating that the cytosolic androgen receptor was nonfunctional. Pedigree analysis indicates that this is an X-linked disorder in cats, as it is in other mammals. Accurate diagnosis and genetic counseling are advocated to reduce the prevalence of the disorder.

Improved anti-tumor reactivity with monoclonal anti-idiotypic antibody conjugated to syngeneic mouse red blood cells

An anti-idiotypic (anti-Id) antibody (Ab), by resembling an epitope on an antigenic molecule may serve as a surrogate antigen and induce specific immune reactivity to the natural antigen. Anti-Id Ab are often conjugated to a foreign protein, such as keyhole limpet hemocyanin (KLH) to elicit a stronger response. However, KLH, a potent antigen itself, may provoke unnecessary and undesirable immune reactivity. In this study, syngeneic mouse red blood cells (RBC) were tested as carriers for anti-Id immunization. In a preliminary experiment, BALB/c mice were immunized with normal rat immunoglobulin G (NRIg)-MRBC or NRIg-KLH. Anti-NRIg responses induced by 2-0.2% of NRIg-MRBC (4-0.4 micrograms of NRIg) superseded those induced by NRIg-KLH (50 micrograms of NRIg). Immunization with NRIg-MRBC did not result in autoreactivity against self antigens on autologous RBC. Monoclonal antibody 2F10, which resembles an epitope on mouse mammary tumor virus (MMTV) envelop protein Gp52, was conjugated to MRBC and used as a surrogate antigen for Gp52. Immune sera were tested in cytotoxicity assay against MMT 68H which expresses Gp52. Between 2-4 weeks after the immunization, specific cytotoxic antibodies were detected in mice immunized with 2.0%, 0.2% and 0.02% 2F10-MRBC, with 0.2% 2F10-MRBC being the most effective dose. 2F10 immune sera did not react with autologous RBC. Therefore, MRBC are at least as effective, and may be more effective than KLH as carriers for Ig immunization. Repeated treatment will be feasible since MRBC are not immunogenic.

Neurotoxicity of a fragment of the amyloid precursor associated with Alzheimer's disease

Amyloid deposition in senile plaques and the cerebral vasculature is a marker of Alzheimer's disease. Whether amyloid itself contributes to the neurodegenerative process or is simply a by-product of that process is unknown. Pheochromocytoma (PC12) and fibroblast (NIH 3T3) cell lines were transfected with portions of the gene for the human amyloid precursor protein. Stable PC12 cell transfectants expressing a specific amyloid-containing fragment of the precursor protein gradually degenerated when induced to differentiate into neuronal cells with nerve growth factor. Conditioned medium from these cells was toxic to neurons in primary hippocampal cultures, and the toxic agent could be removed by immunoabsorption with an antibody directed against the amyloid polypeptide. Thus, a peptide derived from the amyloid precursor may be neurotoxic.

Vulnerability factors in the transition to university: self-reported mobility history and sex differences as factors in psychological disturbance

A study was conducted on the psychological reaction to the transition to university in 198 first year residential students. Female subjects had higher levels of psychological disturbance and cognitive failure. Thirty-one per cent of the subjects reported experiencing homesickness. These subjects had higher levels of psychological disturbance and cognitive failure than non-homesick subjects. There were no sex differences in homesickness reporting. The non-homesick group were found to be more likely to have been away from home before either to attend boarding school or to take holidays. This suggests either that selective aspects of previous mobility experience are beneficial or that self-selection factors operate in that those who do not feel distress at leaving home are more likely to acquire mobility experience.

Short- and long-term effects of auxiliary labels on patient knowledge of precautionary drug information

The purpose of this study was to determine the efficacy of auxiliary prescription labels in educating outpatients about medicines at two different time periods. Five hundred fifty-nine patients were randomly assigned either to an experimental group or a control group; each person in the experimental group received a prescription bottle to which one study auxiliary label ("sticker") had been affixed, and those in the control group received bottles with no study sticker attached. Patients were interviewed by telephone approximately one week or two months after prescription pick up. Patients who had the study sticker affixed to their prescription bottle were significantly more knowledgeable after one week about precautionary information than those patients who did not receive stickers; however, sticker-group patients receiving the delayed interview incorrectly attributed many precautions to their medication. This is the first controlled study to document that auxiliary labels increase short-term knowledge about medications, and to suggest that the same labels may result in an inappropriate generalization over time.

Primary radiation therapy for stage I and II breast cancer

In 1987 there were estimated to be approximately 130,000 new cases of breast cancer diagnosed in the United States. Presently, about 20-30,000 of these cases are treated with primary radiotherapy, although many more of the 90,000 stage I and II breast cancer cases are eligible for this form of treatment. Appropriate selection must be employed, including the size and site of the primary tumor, the size of the breast, the potential for multifocal disease, and the age of the patient. When proper selection is used, primary radiotherapy for stage I and II disease yields equivalent overall survival and NED survival when compared to traditional mastectomy. The benefit is preservation of the breast with good to excellent cosmesis in the vast majority of patients.

The intraperitoneal delivery of radiolabeled monoclonal antibodies: studies on the regional delivery advantage

The i.p. delivery of murine monoclonal antibody was compared with i.v. delivery in normal mice and rats, in normal nude mice and in those with i.p. human ovarian carcinoma xenografts. In normal rats, all classes of antibodies and antibody fragments evaluated were cleared from the peritoneal cavity at comparable rates. The regional delivery (Rd1) advantage to the peritoneal cavity following i.p. delivery was thus most dependent on the rate of clearance of the antibody or fragment from the blood stream. Determining the exact i.p. delivery advantage was problematic due to the difficulty in reliably obtaining peritoneal fluid later than 9-10 h after i.p. injection in normal animals. During the first 9 h following i.p. injection, the Rd(0-9/0-9) was, for a murine IgG2ak Fab greater than F(ab')2 greater than IgG (at 13.6 greater than 10 greater than 7.9). Two murine IgMs evaluated differed in Rd(0-9) at 27.1 and 9.2 respectively. When blood levels were extrapolated to infinity, these Rd (0-9/affinity) values were considerably lower with the Fab having the highest Rd at 4.67. The i.p. Rd advantage was almost solely due to the i.p. antibody levels seen in the first 24 h after injection, as after that time, blood levels become comparable to those seen following i.v. injection. Normal tissues obtained at sacrifice 5-7 days after i.p. injection. Normal tissues obtained at sacrifice 5-7 days after i.p. or i.v. injection in rats showed comparable levels of radioantibody activity, whether the injection was i.p. or i.v. (except for higher diaphragmatic levels following i.p. delivery). In nude mice with i.p. human-derived ovarian tumors, intact IgG clearance from the peritoneal cavity to the blood was considerably slower than in normal animals, and early i.p. tumor uptake of specific antibody was significantly higher than that following i.v. antibody delivery. With higher early tumor uptake and lower systemic exposure, early tumor/nontumor ratios were significantly greater than those for i.v. delivery, though not beyond 48 h after i.p. injection. This study demonstrates the pharmacokinetic rationale for i.p. monoclonal antibody delivery, especially for agents cleared rapidly from the blood, such as antibody fragments. In addition, definite i.p. delivery benefit for antibody specific to i.p. tumors in the i.p. ovarian cancer system was shown soon after injection. These data regarding i.p. antibody delivery should be useful in rationally planning diagnostic and therapeutic studies involving the i.p. delivery of unmodified and immunoconjugated monoclonal antibodies.

Improved radioimmunolocalization of human tumor xenografts following subcutaneous delivery of monoclonal antibodies

The localization of a radiolabeled murine monoclonal antibody reactive with choriocarcinomas to human choriocarcinoma xenografts following intravenous and subcutaneous injection was evaluated by gamma scanning and tissue sampling. Tumor xenografts were established in the popliteal node region of athymic nude mice after repeated innoculations of the hind foot pads with BEWO choriocarcinoma cells. In dual label specific antibody studies, tumor/non tumor uptake ratios following subcutaneous (resulting in considerable intralymphatic uptake) injection of 131I-5F9.3 were significantly higher than those achieved post simultaneous intravenous injection of 125I-5F9.3. Double label experiments with 131I-5F9.3 and a nonspecific antibody, 125I-UPC-10, following subcutaneous injection, demonstrated that the high localization to popliteal region tumors was largely due to antibody specificity. Gamma scans following subcutaneous antibody administration of specific antibody to tumor bearing animals showed tumors soon after subcutaneous injection, at times earlier than those typically seen following intravenous delivery. Similar subcutaneous injections showed little normal nodal uptake in BALB/c control animals on gamma scans. No correlation was seen between tumor localization by specific antibody between the intravenous and intralymphatic routes, implying a difference in the mechanisms of tumor uptake of antibody by these two routes. The subcutaneous approach to antibody delivery offers advantages over intravenous delivery in tumors of human origin, including higher tumor/non tumor ratios and earlier imaging times. This was true even though these tumors were many times larger than normal lymph nodes. This subcutaneous delivery advantage should be exploitable in imaging nodal metastases of human tumors.

Plasma and tissue concentrations of ceforanide and cefazolin in women undergoing hysterectomy

Thirty-four women who underwent vaginal hysterectomy received either ceforanide or cefazolin as perioperative antimicrobial prophylaxis. Samples of plasma, myometrium, endometrium and fallopian tubes were obtained at various intervals after injection and were assayed for cephalosporin concentration. Following intramuscular injection approximately 1 h prior to surgery, both drugs provided adequate tissue levels at the time of the procedure. Although both antimicrobials achieved similar tissue concentrations, all tissue samples for ceforanide exceeded the MIC90 for Escherichia coli while in the cefazolin group 9/18 myometrial samples and 10/15 endometrial samples fell below the MIC90 for this organism.

The stress of the transition to university: a longitudinal study of psychological disturbance, absent-mindedness and vulnerability to homesickness

A longitudinal study was conducted to examine the effects of the transition to university in residential and home-based students. All students showed evidence of raised psychological disturbance and absent-mindedness following the transition. Although there were no differences between resident and home-based students in this respect, those who reported homesickness were distinguished from the remainder in terms of higher levels of psychological disturbance and cognitive failure following the transition to university. Covariate analysis established that the gain in psychological disturbance following the transition was greater for the homesick group. The results are discussed in terms of the effects of stressful transitions on psychological state and the concept of personal vulnerability.