Injury Risk Functions for the Midsized Male Wrist and Elbow as a Result of Behind Shield Blunt Trauma

Ballistic shields protect users from a variety of threats, including projectiles. Shield back-face deformation (BFD) is the result of the shield deflecting or absorbing a projectile and deforming toward the user. Back-face deformation can result in localized blunt loading to the upper extremity, where the shield is supported by the user. Two vulnerable locations along the upper extremity were investigated-the wrist and elbow-on eight postmortem human subjects (PMHS) using a pneumatic impacting apparatus for investigating the fracture threshold as a result of behind shield blunt trauma (BSBT). Impacting parameters were established by subjecting an augmented WorldSID anthropomorphic test device (ATD) positioned behind a ballistic shield to ballistic impacts. These data were used to form the impact parameters applied to PMHS, where the wrist most frequently fractured at the distal radius and the elbow most frequently fractured at the radial head. The fracture threshold for the wrist was 5663±1386 N (mean±standard deviation), higher than the elbow at 4765±894 N (though not significantly, p = 0.15). The failure impact velocity for wrist impacts was 17.7±2.1 m/s, while for the elbow, the failure impact velocity was 19.5±0.9 m/s. An approximate 10% risk of fracture threshold was identified on the modified WorldSID ATD (no flesh analogue included) to inform future protective standards.

Injury Risk for the Hand and Forearm Under Loading Representative of Behind Shield Blunt Trauma

Ballistic shields protect users from a variety of threats, including projectiles. Shield back-face deformation (BFD) is the result of the shield absorbing energy from a projectile and deforming towards the user. Back-face deformation can result in localized blunt loading to the upper extremity, where the shield is supported by the user and may cause injury through behind armour blunt trauma (BABT) mechanisms. Post-mortem human subject (PMHS) responses are critical to identify the injury risk in these high-rate scenarios and are used to quantify the injury tolerance. Two vulnerable locations along the upper extremity were investigated-the hand and forearm-using eight PMHS to identify the fracture threshold resulting from shield BABT loading conditions. Impacts delivered to the hand at 16.4 ± 0.8 m/s resulted in failure loads of 3818 ± 897 N, whilst the forearm impacts delivered at a similar velocity of 16.9 ± 1.9 m/s had lower failure loads at 3011 ± 656 N. The corresponding 10% risk of hand and forearm fractures (as measured on a modified WorldSID Anthropomorphic Test Device) were identified as 11.0 kN and 8.1 kN, respectively, which should be used when evaluating future designs of composite ballistic shields. This study is the first known investigation of the upper extremity to this high loading rate scenario and provides the foundation for future biomechanical research in the area of behind shield blunt trauma.

Mycoplasma bovis testing for the screening of semen imported into New Zealand

AIMS

To evaluate the fitness of three PCR assays for the detection of Mycoplasma bovis in dilute (extended) bovine semen, and a reverse transcriptase-PCR (RT-PCR) adaptation as a proxy for viability.

MATERIALS AND METHODS

Four commercial kit-based methods for nucleic acid extraction were compared to test for the presence of PCR inhibitors in nucleic acid extracted from undiluted and diluted semen. Then, analytical sensitivity, analytical specificity, and diagnostic specificity of two real-time PCR and one conventional PCR were evaluated for the detection of M. bovis DNA in semen and compared against microbial culture. Furthermore, an RT-PCR was adapted to detect RNA only and tested on viable and non-viable M. bovis to establish its ability to discriminate between the two.

RESULTS

No significant PCR inhibition was detected from the dilute semen. All DNA extraction methods except one were equivalent, regardless of semen dilution. The analytical sensitivity of the real-time PCR assays was estimated as 45.6 cfu per 200 µL semen straw (2.2 × 10² cfu/mL). The conventional PCR was 10 times less sensitive. No cross-reactivity was observed for the real-time PCR for any of the bacteria tested and the diagnostic specificity was estimated as 100 (95% CI = 94.04-100) %. The RT-PCR was poor in distinguishing between viable and non-viable M. bovis. The mean quantification cycle (Cq) values for RNA extracted from different treatments to kill M. bovis remained unchanged 0-48 hours after inactivation.

CONCLUSION AND CLINICAL RELEVANCE

The real-time PCR were fit for the purpose of screening dilute semen for the detection of M. bovis to prevent incursion via importation of infected semen. The real-time PCR assays can be used interchangeably. The RT-PCR could not reliably indicate the viability of M. bovis. Based on the results from this study, a protocol and guidelines have been produced for laboratories elsewhere that wish to test bovine semen for M. bovis.

The Impact of COVID-19 on Outpatient Antibiotic Prescriptions in Ontario, Canada; An Interrupted Time Series Analysis

Background

The coronavirus disease 2019 (COVID-19) pandemic has potentially impacted outpatient antibiotic prescribing. Investigating this impact may identify stewardship opportunities in the ongoing COVID-19 period and beyond.

Methods

We conducted an interrupted time series analysis on outpatient antibiotic prescriptions and antibiotic prescriptions/patient visits in Ontario, Canada, between January 2017 and December 2020 to evaluate the impact of the COVID-19 pandemic on population-level antibiotic prescribing by prescriber specialty, patient demographics, and conditions.

Results

In the evaluated COVID-19 period (March–December 2020), there was a 31.2% (95% CI, 27.0% to 35.1%) relative reduction in total antibiotic prescriptions. Total outpatient antibiotic prescriptions decreased during the COVID-19 period by 37.1% (95% CI, 32.5% to 41.3%) among family physicians, 30.7% (95% CI, 25.8% to 35.2%) among subspecialist physicians, 12.1% (95% CI, 4.4% to 19.2%) among dentists, and 25.7% (95% CI, 21.4% to 29.8%) among other prescribers. Antibiotics indicated for respiratory infections decreased by 43.7% (95% CI, 38.4% to 48.6%). Total patient visits and visits for respiratory infections decreased by 10.7% (95% CI, 5.4% to 15.6%) and 49.9% (95% CI, 43.1% to 55.9%). Total antibiotic prescriptions/1000 visits decreased by 27.5% (95% CI, 21.5% to 33.0%), while antibiotics indicated for respiratory infections/1000 visits with respiratory infections only decreased by 6.8% (95% CI, 2.7% to 10.8%).

Conclusions

The reduction in outpatient antibiotic prescribing during the COVID-19 pandemic was driven by less antibiotic prescribing for respiratory indications and largely explained by decreased visits for respiratory infections.

Recurrent life-threatening reactions to platelet transfusion in an aplastic anaemia patient with a paroxysmal nocturnal haemoglobinuria clone

A 60-year-old woman was diagnosed with non-severe aplastic anaemia when she presented with anaemia and thrombocytopenia. She developed recurrent life-threatening hypotensive reactions during transfusion of leukodepleted platelet concentrates, and washed platelet concentrates prevented the development of such reactions subsequently. A paroxysmal nocturnal haemoglobinuria clone was detected on investigating for aplastic anaemia, which has been speculated to play a role in the recurrent hypotensive reactions.

An atypical genotype of Toxoplasma gondii as a cause of mortality in Hector's dolphins (Cephalorhynchus hectori)

Hector's dolphins (Cephalorhynchus hectori) are a small endangered coastal species that are endemic to New Zealand. Anthropogenic factors, particularly accidental capture in fishing nets, are believed to be the biggest threat to survival of this species. The role of infectious disease as a cause of mortality has not previously been well investigated. This study investigates Toxoplasma gondii infection in Hector's dolphins, finding that 7 of 28 (25%) dolphins examined died due to disseminated toxoplasmosis, including 2 of 3 Maui's dolphins, a critically endangered sub-species. A further 10 dolphins had one or more tissues that were positive for the presence of T. gondii DNA using PCR. Genotyping revealed that 7 of 8 successfully amplified isolates were an atypical Type II genotype. Fatal cases had necrotising and haemorrhagic lesions in the lung (n=7), lymph nodes (n=6), liver (n=4) and adrenals (n=3). Tachyzoites and tissue cysts were present in other organs including the brain (n=5), heart (n=1), stomach (n=1) and uterus (n=1) with minimal associated inflammatory response. One dolphin had a marked suppurative metritis in the presence of numerous intra-epithelial tachyzoites. No dolphins had underlying morbillivirus infection. This study provides the first evidence that infectious agents could be important in the population decline of this species, and highlights the need for further research into the route of entry of T. gondii organisms into the marine environment worldwide.

Situational analysis of varying models of adherence support and loss to follow up rates; findings from 27 treatment facilities in eight resource limited countries

OBJECTIVES

Large-scale provision of ART in the absence of viral load monitoring, resistance testing, and limited second-line treatment options places adherence support as a vital therapeutic intervention. We aimed to compare patient loss to follow up rates with the degree of adherence support through a retrospective review of patients enrolled in the AIDSRelief program between August 2004 and June 2005.

METHODS

Loss to follow up data were analysed and programs were categorised into one of four tiered levels of adherence support models: Tier I, II, III, and IV which increase from lowest to highest support. Bivariate and t-test analyses were used to test for significant differences between the models.

RESULTS

13,391 patients at 27 treatment facilities from six African and two Caribbean countries began antiretroviral therapy within the first year of the AIDSRelief program. The mean loss to follow up within the first year was 7.5%. Eight facilities were Tier I, three (Tier II), nine (Tier III), and seven (Tier IV). Facilities in Tier I had a loss to follow up rate of 14%, Tier II (10%), Tier III (5%), and Tier IV (1%). The proportion of loss to follow up for Tier I and Tier III were significantly different from each other (P < 0.02), as were Tier I and Tier IV (P < 0.006). There were differences between Tier II and Tier IV (P < 0.009) as well as Tier III and Tier IV (P < 0.017).

CONCLUSION

These data strongly support the use of proactive adherence support programs, beyond routine patient counselling and defaulter tracking to support the'public health approach'to ART.

Utilization of dried blood spots within drug discovery: modification of a standard DiLab® AccuSampler® to facilitate automatic dried blood spot sampling

The use of dried blood spots (DBS) in preclinical studies has seen an enormous increase over the past two years. Despite its positive impact on the 3Rs (reduce, replace and refine), its uptake in exploratory drug discovery has been limited due mainly to protracted method development time in bioanalysis but also the need for small volumes (<20 μL) to be sampled manually. Automatic blood sampling technology such as the DiLab® AccuSampler® is widely used in drug discovery to facilitate exploratory rodent-based pharmacokinetic and pharmacokinetic/pharmacodynamic studies with minimal animal handling. Propranolol was orally administered to a Han-Wistar rat attached to either a standard DiLab® AccuSampler® or a retrofitted unit designed to directly collect the DBS samples. In all, 50 or 20 μL blood samples were then collected via the standard or retrofitted unit, respectively, at six timepoints over a 7 h period. After drying and storage the DBS samples were analysed for propranolol via liquid chromatography-mass spectrometry. In this report we demonstrate that a standard DiLab® AccuSampler® can be easily retrofitted to facilitate automatic dried blood spot sampling and that time–concentration data generated from these samples are equivalent to that from manually spotted samples.

Adjuvant interferon in high-risk melanoma: the AIM HIGH Study--United Kingdom Coordinating Committee on Cancer Research randomized study of adjuvant low-dose extended-duration interferon Alfa-2a in high-risk resected malignant melanoma

PURPOSE

To evaluate low-dose extended duration interferon alfa-2a as adjuvant therapy in patients with thick (> or = 4 mm) primary cutaneous melanoma and/or locoregional metastases.

PATIENTS AND METHODS

In this randomized controlled trial involving 674 patients, the effect of interferon alfa-2a (3 megaunits three times per week for 2 years or until recurrence) on overall survival (OS) and recurrence-free survival (RFS) was compared with that of no further treatment in radically resected stage IIB and stage III cutaneous malignant melanoma.

RESULTS

The OS and RFS rates at 5 years were 44% (SE, 2.6) and 32% (SE, 2.1), respectively. There was no significant difference in OS or RFS between the interferon-treated and control arms (odds ratio [OR], 0.94; 95% CI, 0.75 to 1.18; P =.6; and OR, 0.91; 95% CI, 0.75 to 1.10; P =.3; respectively). Male sex (P =.003) and regional lymph node involvement (P =.0009), but not age (P =.7), were statistically significant adverse features for OS. Subgroup analysis by disease stage, age, and sex did not show any clear differences between interferon-treated and control groups in either OS or RFS. Interferon-related toxicities were modest: grade 3 (and in only one case, grade 4) fatigue or mood disturbance was seen in 7% and 4% respectively, of patients. However, there were 50 withdrawals (15%) from interferon treatment due to toxicity.

CONCLUSION

The results from this study, taken in isolation, do not indicate that extended-duration low-dose interferon is significantly better than observation alone in the initial treatment of completely resected high-risk malignant melanoma.

Contamination of bone marrow products with an actinomycete resembling Microbacterium species and reinfusion into autologous stem cell and bone marrow transplant recipients

Bacterial contamination of bone marrow or peripheral blood stem cell transplant products typically occurs with skin flora or, rarely, gram-negative organisms. We describe a clonal outbreak of contamination in transplant products caused by contamination with an aerobic actinomycete that occurred at our institution during the summer of 2001. From 1 July through 12 September 2001, 73 peripheral blood or bone marrow stem cell products were obtained from 39 patients, and 34 products were found to be contaminated with the outbreak strain. Fourteen patients were reinfused with contaminated cells, and the outbreak strain was isolated from the blood cultures for one patient. Investigation revealed multiple potential sources for contamination during the product cryopreservation process. The outbreak of contamination was aborted upon modification of the cryopreservation process.

The influence of acute rejection on long-term renal allograft survival: a comparison of living and cadaveric donor transplantation

BACKGROUND

We investigated whether recipients of living donor grafts who suffer an acute rejection progress to graft loss because of chronic rejection at a slower rate than recipients of cadaveric grafts.

METHODS

A retrospective review was made of 296 renal transplantations performed at Mount Sinai Hospital. Only grafts functioning for at least 3 months were included in this analysis. Demographic variables of donor and recipient age, race, sex, and serum creatinine at 3 months after transplantation were compared between groups.

RESULTS

Among the acute rejection-free cohort, the estimated 5-year graft survival was 90% for those receiving transplants from living relatives and 88% for those receiving cadaveric transplants (P=0.76). However, in grafts with early acute rejection, the 5-year survival was 40% for cadaveric recipients compared with 73% for living related graft recipients (P<0.014). Using the proportional hazards model, cadaveric donor source, older donor age, African American recipient race, and elevated 3-month serum creatinine were independent predictors of long-term graft loss caused by chronic rejection. The severity of acute rejection and recipient age had no impact on the risk of graft loss because of chronic rejection.

CONCLUSION

These data indicate that the benefit of living related transplantation results from the fact that a living related graft progresses from acute to chronic rejection at a slower rate than a cadaveric graft. Furthermore, a cadaveric graft that is free of acute rejection 3 months after transplantation has an equal likelihood of functioning at 5 years as that of a graft from a living related donor.

Production of recombinant soluble human integrin alpha4beta1

Integrin alpha4beta1 is a major leukocyte adhesion receptor that is a key target for the development of anti-inflammatory therapeutics. With the dual long-term goals of developing a reagent for use in high-throughput inhibitor screening assays and for crystallisation trials and subsequent structure determination, we have generated a recombinant soluble alpha4beta1 receptor. Both subunits were truncated prior to the transmembrane domains by site-directed mutagenesis and expressed using baculovirus infection of insect cells. The molecular weights of the recombinant subunits were as expected for post-translationally unmodified protein. In addition, as observed for the native subunit, a proportion of the alpha4 subunit was proteolytically processed into two fragments. ELISA and solid phase ligand-binding assays were performed to investigate the folding and functionality of the soluble integrin. The data suggest that the receptor was correctly folded and that it bound recombinant ligands with similar kinetics to the native molecule.

Isotretinoin improves the appearance of photodamaged skin: results of a 36-week, multicenter, double-blind, placebo-controlled trial

Photodamaged skin occurs as a result of long-term exposure to ultraviolet radiation. The incidence of photodamage in European and North American populations with Fitzpatrick skin types I, II, and III is estimated at 80% to 90%. We conducted a double-blind clinical trial to test the efficacy and safety of 0.1% isotretinoin versus vehicle cream in 800 patients with moderate to severe photodamaged skin. Patients applied either 0.1% isotretinoin or matching vehicle cream to the face, forearms, and hands once nightly for 36 weeks. Local irritation and adverse events were assessed, and plasma retinoid levels were measured before and during treatment. Treatment response increased throughout the 36-week treatment period and the overall appearance of photodamaged skin was significantly better than with the vehicle alone. Topical application of 0.1% isotretinoin is an effective and well-tolerated treatment leading to clinically apparent improvement in the appearance of photodamaged skin of the face, forearms, and hands.

Anatomy of pelvic arteries adjacent to the sacrospinous ligament: importance of the coccygeal branch of the inferior gluteal artery

OBJECTIVE

To describe the arterial vascular anatomy in the area of the sacrospinous ligament.

METHODS

Cadaver pelvises were dissected to reveal the anatomy of the sacrospinous ligament with emphasis on vascular and neuroanatomy. Flexible rulers were used to measure the coccygeal branch in five hemipelvises.

RESULTS

The pudendal vessels and nerve pass immediately medial and inferior to the ischial spine (within 0.5 cm of the spine) and behind the sacrospinous ligament. The pudendal artery lies anterior to the sacrotuberous ligament, which passes behind the ischial spine to its attachment at the posterior ischial tuberosity. The inferior gluteal artery originates from the posterior or the anterior branch of the internal iliac artery to pass behind the sciatic nerve and the sacrospinous ligament. There is a 3- to 5-mm window in which the inferior gluteal vessel is left uncovered above the top of the sacrospinous ligament and below the lower edge of the main body of the sciatic nerve plexus. The coccygeal branch of the inferior gluteal artery passes immediately behind the midportion of the sacrospinous ligament and pierces the sacrotuberous ligament in multiple sites. The main body of the inferior gluteal artery leaves the pelvis by passing posterior to the upper edge of the sacrospinous ligament and following the inferior portion of the sciatic nerve out of the greater sciatic foramen.

CONCLUSION

Sutures placed through the sacrospinous ligament at least 2.5 cm from the ischial spine along the superior border of the sacrospinous ligament and without transgressing the entire thickness are in an area generally free of arterial vessels.

Fine mapping of inhibitory anti-alpha5 monoclonal antibody epitopes that differentially affect integrin-ligand binding

The high-affinity interaction of integrin alpha5beta1 with the central cell-binding domain of fibronectin requires both the Arg-Gly-Asp (RGD) sequence (in the tenth type III repeat) and a second site Pro-His-Ser-Arg-Asn (PHSRN) in the adjacent ninth type III repeat, which synergizes with RGD. Arg-Arg-Glu-Thr-Ala-Trp-Ala (RRETAWA) is a novel peptidic ligand for alpha5beta1, identified by phage display, which blocks alpha5beta1-mediated cell adhesion to fibronectin. A key question is the location of the binding sites for these ligand sequences within the integrin. In this study we have identified residues that form part of the epitopes of three inhibitory anti-alpha5 monoclonal antibodies (mAbs): 16, P1D6 and SNAKA52. These mAbs have distinct functional properties. mAb 16 blocks the recognition of RGD and RRETAWA, whereas P1D6 blocks binding to the synergy sequence. The binding of SNAKA52 is inhibited by anti-beta1 mAbs, indicating that its epitope is close to the interface between the alpha and beta subunits. Residues in human alpha5 were replaced with the corresponding residues in mouse alpha5 by site-directed mutagenesis; wild-type or mutant human alpha5 was expressed on the surface of alpha5-deficient Chinese hamster ovary cells. mAb binding was assessed by flow cytometry and by adhesion to the central cell-binding domain of fibronectin or RRETAWA by cell attachment assay. All three epitopes were located to different putative loops in the N-terminal domain of alpha5. As expected, disruption of these epitopes had no effect on ligand recognition by alpha5beta1. The locations of these epitopes are consistent with the beta-propeller model for integrin alpha-subunit structure and allow us to propose a topological image of the integrin-ligand complex.

'Tis better to receive than to give: the relative failure of the African American community to provide organs for transplantation

There is a serious, continuous and increasing shortfall of organs, especially kidneys, for the purpose of transplantation. This shortfall is especially remarkable in African American populations. Because the incidence of hypertension (HTN) and associated end-stage renal diseases (ESRD) is 17 times greater in African Americans, this minority group, which comprises only 12% of the U.S. population, represents 34% of the dialysis population and 30% of the national kidney waiting list. Furthermore, while black individuals comprise 22-24% of kidney recipients, they comprise only 8-11% of donors. Because of the histocompatibility differences between the races and because tissue matching is part of the United Network for Organ Sharing (UNOS) allocation formula, African Americans wait twice as long for kidneys as Caucasians. Also, because they get more poorly matched organs, their kidney transplant graft survival is 10-20% lower than that for other racial groups. The African American community is unaware of the special needs in members of their own race. Steps must be taken to increase minority awareness of the need for well-matched transplant organs and their involvement in the donation process.

Successful transplantation of pediatric en bloc kidneys with bilateral double ureters

We report a case in which en bloc kidneys with bilateral double ureters from a 5-month-old donor were successfully transplanted into a 25-year-old recipient. No stents were used. There were no complications after the transplant. The patient remains well at more than 1.5 years post-transplantation with serum creatinine 1.2 mg/dl.

The combined impact of donor age and acute rejection on long-term cadaver renal allograft survival

BACKGROUND

Acute rejection (AR) is an important risk factor for long-term renal graft loss. Furthermore, donor age is also associated with graft outcome. We analyzed the combined effects of cadaver donor age and AR on long-term graft survival.

METHODS

A retrospective review was made of 112 cadaver renal transplants at a single center. Only grafts functioning at least 3 months were included in this analysis.

RESULTS

The 3-year survival of AR-free grafts was superior to that of grafts with AR (98% vs 67%, P < .001). Within the AR cohort donor age > 50 years (P < .05) had an additional negative impact on graft survival. The 3-year survival of an older donor graft with AR was 33% versus 82% for a younger donor graft with AR.

CONCLUSIONS

AR was a significant predictor of long-term graft loss. Older donor kidneys with AR had poorer graft survival than did younger donor kidneys with AR.

Evaluating sensory conflict and postural instability. Theories of motion sickness

Two experiments were carried out to evaluate the sensory conflict and the postural instability theories of motion sickness. The central hypothesis of sensory conflict theory is that motion sickness is caused by conflict between the current pattern of sensory inputs about self-movement and the pattern that is expected on the basis of previous experience. A subsidiary hypothesis is that the degree of motion sickness is proportional to the magnitude of sensory conflict. The central hypothesis of postural instability theory is that motion sickness is caused by loss of postural control. A subsidiary hypothesis is that the degree of motion sickness is proportional to amount of postural instability, which can be manipulated by physical restraint. In both experiments there were two levels of sensory conflict and two levels of postural restraint. Dependent variables were latency of onset and severity of motion sickness. The widespread occurrence of motion sickness in both experiments clearly confirmed the main hypothesis of sensory conflict theory. The results from Experiment 1, that there was significantly more motion sickness in the restrained condition, and from Experiment 2, that there was no significant difference in symptoms between the two restraint conditions, provide no support for the subsidiary hypothesis of postural instability theory. Evidence relating to the subsidiary proposition of sensory conflict theory was inconsistent.

Identification of amino acid residues that form part of the ligand-binding pocket of integrin alpha5 beta1

Arg-Arg-Glu-Thr-Ala-Trp-Ala (RRETAWA) is a novel ligand peptide for integrin alpha5 beta1, which blocks alpha5 beta1-mediated cell adhesion to fibronectin (Koivunen, E., Wang, B., and Ruoslahti, E. (1994) J. Cell Biol. 124, 373-380). Here we have localized the binding site for RRETAWA on alpha5 beta1 using inhibitory monoclonal antibodies (mAbs) and site-directed mutagenesis. A cyclic peptide containing this sequence (*CRRETAWAC*) had little effect on the binding of most anti-alpha5 and anti-beta1 mAbs to alpha5 beta1 but completely blocked binding of the anti-alpha5 mAb 16 in a directly competitive manner. Hence, the binding site of RRETAWA appears to closely overlap with the epitope of mAb 16. *CRRETAWAC* also acted as a direct competitive inhibitor of the binding of Arg-Gly-Asp (RGD)-containing fibronectin fragments to alpha5 beta1, suggesting that the binding site for RRETAWA is also closely overlapping with that for RGD. However, differences between the binding sites of RRETAWA and RGD were apparent in that (i) RGD peptides allosterically inhibited the binding of mAb 16 to alpha5 beta1, and (ii) several mAbs that perturbed binding of alpha5 beta1 to RGD had little effect on binding of alpha5 beta1 to RRETAWA. A double mutation in alpha5 (S156G/W157S) blocked the interaction of both RRETAWA and mAb 16 with alpha5 beta1 but had no effect on fibronectin binding or on the binding of other anti-alpha5 mAbs. Ser156-Trp157 is located near the apex of a putative loop region on the upper surface of a predicted beta-propeller structure formed by the NH2-terminal repeats of alpha5. Our findings suggest that this sequence forms part of the ligand-binding pocket of alpha5 beta1. Furthermore, as Ser156-Trp157 is unique to the alpha5 subunit, it may be responsible for the specific recognition of RRETAWA by alpha5 beta1.

Regulation of the extracellular ligand binding activity of integrins

Integrins are a large heterodimeric family of cell surface adhesion receptors that bind extracellular matrix and cell surface ligands. The extracellular ligand binding activity of integrins is a dynamic and highly regulated event involving the induction of conformational changes within the integrin structure. The adhesive properties of integrins can be controlled by altering the activation state of the integrin, either through conformational change or receptor clustering, using mechanisms that are regulated by intracellular proteins. In this review, we will discuss what is currently known about integrin structure and the ligand binding sites present within the receptor. In addition, the mechanisms by which the ligand binding event is regulated through conformational change will be addressed, and the potential role of intracellular cytoplasmic proteins will be discussed.

Transient hypoadrenalism during surgical critical illness

OBJECTIVE

To report the cortisol levels in 6 patients during and after severe inflammation.

DESIGN

Patients with severe inflammatory disease had basal and stimulated (cosyntropin) serum cortisol levels determined at the time of severe and less severe inflammation.

SETTING

Intensive care unit and wards of a tertiary care center.

PATIENTS

Six patients with continued evidence of severe inflammation, despite aggressive management of the underlying inflammatory disease.

INTERVENTIONS

Five of 6 patients received hydrocortisone at "physiologic" doses.

MAIN OUTCOME MEASURES

Basal and stimulated serum cortisol levels.

RESULTS

The mean+/-SD cortisol data for these patients were as follows: baseline cortisol level during inflammation, 350+/-121 nmol/L (n=6); stimulated cortisol level during inflammation, 571+/-326 nmol/L (n=6); baseline cortisol level with less inflammation, 833+/-339 nmol/L (P=.03 vs baseline level during inflammation) (n=5); and stimulated cortisol level with less inflammation, 1090+/-295 nmol/L (P=.03 vs stimulated level during inflammation) (n=4). Manifestations of inflammation decreased with hydrocortisone administration.

CONCLUSIONS

Severe inflammation may result in lower-than-expected serum cortisol levels, which then increase significantly as the inflammation decreases. Transient hypoadrenalism may aggravate the adverse effects of severe inflammation. These effects may be ameliorated by administering physiologic rather than pharmacologic doses of hydrocortisone.

The effect of pregnancy on cyclosporine levels in renal allograft patients

OBJECTIVE

To assess the effects of pregnancy on cyclosporine levels in six renal allograft patients.

METHODS

Maternal demographic, laboratory, clinical, and perinatal outcome data were recorded in six pregnant women with previous renal allografts receiving cyclosporine immunosuppression. The cyclosporine and serum creatinine levels were measured before pregnancy, during each trimester, and postpartum.

RESULTS

The mean (standard deviation [SD]) maternal age was 29.1 (3.8) years. Parity ranged from 0 to 3. Mean serum creatinine levels tended to be lower during pregnancy than before or after, as did the mean cyclosporine levels. After adjusting for dose, five of six patients had declines in cyclosporine level during pregnancy. The mean (SD) gestational age at delivery was 37.5 (2.8) weeks with a mean (SD) birth weight of 2837 (538) g.

CONCLUSION

Pregnancy in patients with renal allografts can lead to a substantial decline in cyclosporine levels.

Selective binding of N-acetylglucosamine to the chicken hepatic lectin

Among Ca2+-dependent (C-type) animal lectins, the chicken hepatic lectin (CHL) is unique in displaying almost complete selectivity for N-acetylglucosamine over other monosaccharide ligands. The crystal structures of the carbohydrate-recognition domain (CRD) from serum mannose-binding protein (MBP) and of a complex between the CRD from liver MBP and the methyl glycoside of N-acetylglucosamine were used to model the binding site in CHL. Substitution of portions of CHL into the MBP framework did not substantially increase selectivity. A bacterial expression system for the CRD of CHL was developed so that specific residues predicted to be near the 2-acetamido substituent of N-acetylglucosamine could be altered by site-directed mutagenesis. The results indicate that the ligand is bound to CHL in the same orientation as it binds to liver MBP. A tyrosine and a valine residue that probably contact the the N-acetyl group have been identified. These results, together with studies of ligand-binding selectivity, suggest that these residues form part of a binding pocket for the N-acetyl group, which confers selective binding of N-acetylglucosamine.

Automaticity of social behavior: direct effects of trait construct and stereotype-activation on action

Previous research has shown that trait concepts and stereotype become active automatically in the presence of relevant behavior or stereotyped-group features. Through the use of the same priming procedures as in previous impression formation research, Experiment 1 showed that participants whose concept of rudeness was printed interrupted the experimenter more quickly and frequently than did participants primed with polite-related stimuli. In Experiment 2, participants for whom an elderly stereotype was primed walked more slowly down the hallway when leaving the experiment than did control participants, consistent with the content of that stereotype. In Experiment 3, participants for whom the African American stereotype was primed subliminally reacted with more hostility to a vexatious request of the experimenter. Implications of this automatic behavior priming effect for self-fulfilling prophecies are discussed, as is whether social behavior is necessarily mediated by conscious choice processes.

A multicenter trial of FK506 (tacrolimus) therapy in refractory acute renal allograft rejection. A report of the Tacrolimus Kidney Transplantation Rescue Study Group

A multicenter trial was conducted to evaluate the efficacy and safety of tacrolimus in the treatment of refractory renal allograft rejection. Renal transplant recipients experiencing biopsy-proven recurrent acute allograft rejection were eligible if the current rejection episode was refractory to corticosteroids. A total of 73 patients were enrolled, of whom 59 (81%) had previously received at least one course of antilymphocyte antibody as rejection therapy. One-year follow-up was available in 93% of patients. Median time to tacrolimus rescue therapy was 75 days after transplantation (range, 18-1448 days). Therapeutic responses to tacrolimus included improvement in 78% of patients, stabilization in 11%, and progressive deterioration in 11%. The risk of experiencing progressive deterioration was related to the pretacrolimus serum creatinine level: serum creatinine < or = mg/dl, 3%; 3.1-5 mg/dl, 16% (P < 0.04); > 5 mg/dl, 23% (P < 0.02). Twelve-month (from the time of initiation of tacrolimus therapy) actuarial patient and graft survival rates were 93% and 75%. Graft loss occurred in 19 patients (25%) at a median time of 108 days. Fourteen episodes of recurrent rejection were diagnosed in 10 patients (14%), at a median time of 101 days. Eleven episodes of recurrent rejection were treated (three patients underwent transplant nephrectomy), with resolution achieved in nine patients. Antilymphocyte antibody therapy was not used to treat recurrent rejection. Serum creatinine values improved during tacrolimus therapy: median serum creatinine level before tacrolimus, 3.2 mg/dl; median at 1 year after tacrolimus, 1.8 mg/dl. Twelve infections were documented in 11 patients (15%), including cytomegalovirus infection in three patients (4%). Posttransplant lymphoproliferative disorder was diagnosed in a single patient. Tacrolimus whole blood levels averaged 15.0 +/- 9.9 ng/ml at day 7 of tacrolimus therapy and 9.4 +/- 5.1 ng/ml at 1 year, and were consistent among individual centers. Treatment outcome did not correlate with tacrolimus blood levels. The most commonly observed adverse events were neurological and gastrointestinal. Seventy-four percent of patients received tacrolimus for at least 1 year. Tacrolimus therapy was discontinued in 18% of patients for rejection (11% for progressive, unrelenting rejection, and 7% for recurrent rejection). Tacrolimus therapy was discontinued in 8% of patients due to adverse events. In conclusion, tacrolimus rescue therapy provides (1) prompt, effective reversal of refractory renal allograft rejection, (2) good long-term renal allograft function, (3) a low incidence of recurrent rejection, and (4) an acceptable safety profile in renal allograft recipients experiencing refractory rejection.

Automaticity of social behavior: direct effects of trait construct and stereotype-activation on action

Previous research has shown that trait concepts and stereotype become active automatically in the presence of relevant behavior or stereotyped-group features. Through the use of the same priming procedures as in previous impression formation research, Experiment 1 showed that participants whose concept of rudeness was printed interrupted the experimenter more quickly and frequently than did participants primed with polite-related stimuli. In Experiment 2, participants for whom an elderly stereotype was primed walked more slowly down the hallway when leaving the experiment than did control participants, consistent with the content of that stereotype. In Experiment 3, participants for whom the African American stereotype was primed subliminally reacted with more hostility to a vexatious request of the experimenter. Implications of this automatic behavior priming effect for self-fulfilling prophecies are discussed, as is whether social behavior is necessarily mediated by conscious choice processes.

Peritoneal dialysis technician: a process for role definition

Declining reimbursement and rising supply costs have led to use of technicians in peritoneal dialysis. This evolution has helped contain costs effectively while enhancing quality care. Recommendations for use of unlicensed assistive personnel by professional organizations include clear role definition, documented training, and delegation criteria. Applications of technician use in peritoneal dialysis allow nurses to delegate tasks to technicians in harmony with legal and professional standards.

Urine cytology and urine flow cytometry in renal transplantation--a prospective double blind study

Urine cytology (UC) has proved to correlate well with core and fine-needle aspiration kidney biopsies of renal allograft recipients undergoing acute rejection (AR). This study was undertaken to compare the relative usefulness of urine flow immunocytometry (UFC) (using fluorescinated antibodies anti-HLA-DR, anti-CD3 and antirenal epithelial cells) with UC in its ability to diagnose AR by analyzing 200 urine specimens during a prospective double-blind study of 40 renal transplant recipients. Clinical diagnosis was retrospectively assigned to one of the following categories: group I--AR, 15; group II--ischemic injury period (first 5 days postop.), 12; group III, 173 (including 168 stable grafts, 1 pyelonephritis and 4 cyclosporine toxicity), by investigators blinded to the urine results. Both tests were highly sensitive for the diagnosis of AR (UC = 86.6% vs. UFC = 100%; P = NS) with a specificity after the ischemic injury period of 78% by UC and 87.9% by UFC. Samples obtained during AR revealed higher levels of expression of HLA-DR as well as higher numbers of CD3-positive cells. These tests had specificity values of 95.3% and 97.6%, respectively, for the diagnosis of AR. The degree of immune activation (established by numbers of lymphocytes/lymphoblasts seen by UC) correlated with the severity of biopsy-proven ARs and with response to antirejection therapy. In conclusion, both test are highly accurate in diagnosing AR. The highest specificity value was obtained when both UC and UFC were utilized together (93%). We suggest that the routine use of these tests can provide an important adjunct to the evaluation of renal transplant recipients.