Exploring Roles of the Polysaccharide Capsule in Pathogenesis of Hypervirulent Acinetobacter baumannii Clinical Isolate Lac-4

The frequently multidrug-resistant bacterial pathogen Acinetobacter baumannii is a leading cause of nosocomial infections, including ventilator-associated pneumonia, such that the World Health Organization and US Centers for Disease Control and Prevention have declared it a top priority candidate for novel drug development. Nearly all clinical A. baumannii strains express a thick surface polysaccharide capsule that protects against desiccation, host defenses, and disinfectants. In this study, we investigated the contribution of the polysaccharide capsule to virulence caused by the A. baumannii clinical isolate Ab Lac-4, which is rare in its ability to cause pneumonia and disseminated sepsis in healthy mice. We assessed the role of the capsule in wildtype Lac-4 (WT) by generating a premature stop codon in wza, which codes for the polysaccharide export protein. The wza# mutant was hypersensitive to killing by complement, whole blood, and healthy human neutrophils compared to WT and a revertant mutant (wza-Rev). Furthermore, the wza# mutant was highly attenuated in murine sepsis and unable to disseminate from the lungs during pneumonia. This study reinforces the capsule as a key contributor to Ab Lac-4 hypervirulence.

The Group A Streptococcal Vaccine Candidate VAX-A1 Protects against Group B Streptococcus Infection via Cross-Reactive IgG Targeting Virulence Factor C5a Peptidase

Group B Streptococcus (Streptococcus agalactiae or GBS) is the leading infectious cause of neonatal mortality, causing roughly 150,000 infant deaths and stillbirths annually across the globe. Approximately 20% of pregnant women are asymptomatically colonized by GBS, which is a major risk factor for severe fetal and neonatal infections as well as preterm birth, low birth weight, and neurodevelopmental abnormalities. Current clinical interventions for GBS infection are limited to antibiotics, and no vaccine is available. We previously described VAX-A1 as a highly effective conjugate vaccine against group A Streptococcus that is formulated with three antigens, SpyAD, streptolysin O, and C5a peptidase (ScpA). ScpA is a surface-expressed, well-characterized GAS virulence factor that shares nearly identical sequences with the lesser studied GBS homolog ScpB. Here, we show that GBS C5a peptidase ScpB cleaves human complement factor C5a and contributes to disease severity in the murine models of pneumonia and sepsis. Furthermore, antibodies elicited by GAS C5a peptidase bind to GBS in an ScpB-dependent manner, and VAX-A1 immunization protects mice against lethal GBS heterologous challenge. These findings support the contribution of ScpB to GBS virulence and underscore the importance of choosing vaccine antigens; a universal GAS vaccine such as VAX-A1 whose formulation includes GAS C5a peptidase may have additional benefits through some measure of cross-protection against GBS infections.

Effect of supplement crude protein concentration on milk production over the main grazing season and on nitrogen excretion in late-lactation grazing dairy cows

The objectives of this study are to evaluate the effects of (1) a potential interaction between supplement crude protein (CP) concentration and differing cow genotypes on milk production, (2) differing cow genotypes on milk production, and (3) decreasing the supplement CP concentration on milk production and N excretion during the main grazing season within a spring-calving herd. A 2 × 2 factorial arrangement experiment, with 2 feeding strategies [14%; n = 30 (lower CP; LCP) and 18%; n = 28 (higher CP; HCP) CP concentrate supplements] offered at varying levels according to pasture availability and days in milk (DIM) was conducted over the main grazing season from April 3 to September 3, 2019, at University College Dublin Lyons Farm. Cows were also grouped into 2 genotype groups: lower milk genotype; n = 30 [LM; milk kg predicted transmitting ability (PTA): 45 ± 68.6 (mean ± SD); fat kg PTA: 10 ± 4.9; and protein kg PTA: 7 ± 2.3] and higher milk genotype; n = 28 [HM; milk kg PTA: 203 ± 55.0; fat kg PTA: 13 ± 3.8; and protein kg PTA: 10 ± 2.4]. A total of 46 multiparous and 12 primiparous (total; 58) Holstein Friesian dairy cows were blocked on parity and balanced on DIM, body condition score, and Economic Breeding Index. Cows were offered a basal diet of grazed perennial ryegrass pasture. The N partitioning study took place from August 25 to 30, 2019 (187 ± 15.2 DIM). No interactions were observed for any milk production or milk composition parameter. No effect of supplement CP concentration was observed for any total accumulated milk production, daily milk production, or milk composition parameter measured. The HM cows had increased daily milk yield (+1.9 kg), fat and protein (+0.15 kg), and energy-corrected milk (+1.7 kg), compared with the LM cows. Furthermore, HM cows had decreased milk protein concentration (-0.1%) compared with LM cows. For the N partitioning study, cows offered LCP had increased pasture dry matter intake (PDMI; +0.9 kg/d), dietary N intake (+0.022 kg/d), feces N excretion (+0.016 kg/d), and decreased N partitioning to milk (-2%), and N utilization efficiency (-2.3%). In conclusion, offering cows LCP had no negative influence on milk production or milk composition over the main grazing season where high pasture quality was maintained. However, any potential negative effects of offering LCP on milk production may have been offset by the increased PDMI. Furthermore, offering cows LCP decreased N utilization efficiency due to the higher PDMI and feed N intake associated with cows on this treatment in our study.s.

Evaluation of production efficiencies at pasture of lactating suckler cows of diverse genetic merit and replacement strategy

Feed costs account for the largest proportion of direct cost within suckler beef production systems. By identifying the cow type with enhanced capability of converting grazed herbage to beef output across lactations, suckler cow systems would become more efficient and sustainable. The objective of this study was to estimate grass DM intake (GDMI) and production efficiency among lactating suckler cows of diverse genetic merit for the national Irish maternal index (Replacement Index) which includes cow efficiency components such as milk yield and feed intake. Data from 131 cows of diverse genetic merit within the Replacement Index, across two different replacement strategies (suckler or dairy sourced), were available over two grazing seasons. Milk yield, GDMI, cow live weight (BW) and body condition score (BCS) were recorded during early, mid and late-lactation, with subsequent measures of production efficiency extrapolated. Genetic merit had no significant effect on any variables investigated, with the exception of low genetic merit (LOW) cows being 22 kg heavier in BW than high genetic merit (HIGH) cows (P < 0.05). Beef cows were 55 kg heavier in BW (P < 0.001), had a 0.31 greater BCS (P < 0.05) and 0.30 Unité Fourragère Lait (UFL) greater energy requirement for maintenance compared to dairy sourced beef × dairy crossbred (BDX) cows (P < 0.001). The BDX had 0.8 kg greater GDMI, produced 1.8 kg more milk (P < 0.001), had a 0.8 UFL greater energy requirement for lactation and produced weanlings that were 17 kg heavier in BW than beef cows (P < 0.05). Subsequent efficiency variables of milk per 100 kg BW (P < 0.001), milk per kg GDMI (P < 0.001) and GDMI per 100 kg BW (P < 0.001) were more favourable for BDX. The correlations examined showed GDMI had moderate positive correlations (P < 0.001) with intake per 100 kg BW, net energy intake per kg milk yield, RFI and intake per 100 kg calf weaning weight but was weakly negatively correlated to milk yield per kg GDMI (P < 0.001). No difference was observed across genetic merit for beef cows for any of the traits investigated. Results from the current study showed that, while contrasting replacement strategies had an effect on GDMI and production efficiency, no main effect was observed on cows diverse in genetic merit for Replacement Index. Nonetheless, utilising genetic indexes in the suckler herd is an important resource for selecting breeding females for the national herd and phenotypic performance generated from this study can be included in future genetic evaluations to improve reliability of genetic values.

The Fungal Pathogen Candida albicans Promotes Bladder Colonization of Group B Streptococcus

Group B Streptococcus (GBS) is a common cause of bacterial urinary tract infections (UTI) in susceptible populations, including pregnant women and the elderly. However, the factors that govern GBS persistence and disease severity in this niche are not fully understood. Here, we report that the presence of the fungus Candida albicans, a common urogenital colonizer, can promote GBS UTI. Co-inoculation of GBS with C. albicans increased bacterial adherence to bladder epithelium and promoted GBS colonization in vivo in a C. albicans adhesin-dependent manner. This study demonstrates that fungal colonization of the urogenital tract may be an important determinant of bacterial pathogenesis during UTI.

Developing and validating a model to predict the dry matter intake of grazing lactating beef cows

Current techniques for measuring the dry matter intake (DMI) of grazing lactating beef cows are invasive, time consuming and expensive making them impractical for use on commercial farms. This study was undertaken to explore the potential to develop and validate a model to predict DMI of grazing lactating beef cows, which could be applied in a commercial farm setting, using non-invasive animal measurements. The calibration dataset used to develop the model was comprised of 94 measurements recorded on 106 beef or beef-dairy crossbred cows (maternal origin). The potential of body measurements, linear type scoring, grazing behaviour and thermal imaging to predict DMI in combination with known biologically plausible adjustment variables and energy sinks was investigated. Multivariable regression models were constructed for each independent variable using SAS PROC REG and contained milk yield, BW, parity, calving day and maternal origin (dairy or beef). Of the 94 variables tested, 32 showed an association with DMI (P < 0.25) upon multivariable analysis. These variables were incorporated into a backwards linear regression model using SAS PROC REG. Variables were retained in this model if P < 0.05. Five variables; width at pins, full body depth, ruminating mastications, central ligament and rump width score, were retained in the model in addition to milk yield, BW, parity, calving day and maternal origin. The inclusion of these variables in the model increased the predictability of DMI by 0.23 (R2 = 0.68) when compared to a model containing milk yield, BW, parity, calving day and maternal origin only. This model was applied to data recorded on an independent dataset; a herd of 60 lactating beef cows two years after the calibration study. The R2 for the validation was 0.59. Estimates of DMI are required for measuring feed efficiency. While acknowledging challenges in applicability, the findings suggest a model such as that developed in this study may be used as a tool to more easily and less invasively estimate DMI on large populations of commercial beef cows, and therefore measure feed efficiency.

The relative responsiveness and construct validity of the Spanish version of the DASH instrument for outcomes assessment in open carpal tunnel release

The objective of this study was to evaluate the responsiveness and construct validity of the Spanish version of the DASH as outcome measure for carpal tunnel surgery. The study population was 42 patients with the diagnosis of carpal tunnel syndrome (CTS) based on clinical and electrophysiological criteria. The clinical design was a classic Cohort study with measures the day before and 12 weeks after open carpal tunnel release. The Spanish version of the DASH was compared to the physical exam measures as dexterity time, grip and pinch strength, range of motion of the wrist (ROM) and two-point discrimination (2PPD). The responsiveness was evaluated based on the effect size (ES) and the standardised response means (SRM). The Spanish version of the CTS questionnaire (CTQ) and the Spanish version of the 36-item short-form health survey (SF-36) were self-administered to the same study population and followed the same clinical design. The hypothesis that the DASH instrument should present a responsiveness level higher than the SF-36 and lower than the CTQ was established to demonstrate the construct validity. The DASH instrument showed an ES of 0.68 and an SRM of 1.00. Responsiveness of traditional physical exam measures were lower, running from 0.35 (SRM) for dexterity time to 0.00 (ES) for key pinch strength. The SF-36 presented a responsiveness level (range from 0.07 to 0.14) lower that the DASH. The CTQ showed the highest level of responsiveness (ES = 1.41 and 0.7) (SRM = 1.75 and 0.51). In conclusion, The DASH instrument is more sensitive in detecting clinical change than the physical exam measures for use in clinical outcome studies of CTS done at 12 weeks after surgery. The Spanish DASH showed a responsiveness lower than the CTQ and higher than the SF-36 as a proof of a good construct validity.

Anatomic basis for individuated surface EMG and homogeneous electrostimulation with neuroprostheses of the extensor digitorum communis

The extensor digitorum communis (ED) is generally regarded as a fairly undiversified muscle that gives extensor tendons to all fingers. Some fine wire electromyographic (EMG) investigations have been carried out to study individuation of the muscle parts to the different fingers. However, individuated surface EMG of the ED has not been investigated. This study analyses the anatomy of the ED muscle parts to the different fingers in detail and proposes optimal locations for surface or indwelling electrodes for individuated EMG and for electrostimulation with neuroprostheses. The dissections show that the ED arises from extensive origin tendons (OT), which originate at the lateral epicondyle and reach far in the forearm. The ED OT is V-shaped with shorter central tendon fibers but with a long radial and an even longer ulnar slip. The ED parts to the individual fingers consistently arise from distinct OT locations: the ED3 (medius) arises proximally, the ED2 (index) from the radial slip distal to ED3, the ED4 (ring finger) from the ulnar slip distal to ED3, and the ED5 (to ring/little finger) from the ulnar slip distal to ED4. This lengthwise widely spaced arrangement of ED parts compensates to some degree for the narrow ED width and suggests that ED parts should be individually assessable by indwelling and even by surface EMG electrodes, albeit in the latter case with variable mutual cross-talk. Conversely, the anatomic spacing of ED parts warrants that electromyographic stimulation with neuroprostheses by a single implanted electrode cannot likely homogeneously activate all ED parts.

Major complications of epidural analgesia after surgery: results of a six-year survey

We performed a retrospective case note review to identify the major complications of epidural analgesia occurring after surgery at our hospital. By cross-referencing the radiology, microbiology and patient information management system databases, we identified patients who had undergone either spinal magnetic resonance imaging or a lumbar puncture within 60 days of surgery in the period from January 2000 to December 2005. Review of these case notes identified six cases of epidural abscess, three of meningitis and three of epidural haematoma. Symptoms of epidural abscess or meningitis developed a median of 5 days after epidural catheter removal. Methicillin-resistant Staphylococcus aureus was the predominant pathogen. Epidural haematoma symptoms developed while the epidural catheter was in place. These symptoms were initially attributed to the epidural infusion. Diagnostic delays contributed to adverse neurological outcome in three patients. This study suggests that leg weakness is a critical monitor of spinal cord health. A national database is needed to establish a more accurate estimate of the incidence of major complications and to identify relevant risk factors.

Late-onset central hypoventilation syndrome: a family genetic study

Congenital central hypoventilation syndrome is a rare disorder characterised by chronic alveolar hypoventilation, which becomes more pronounced during sleep and may be associated with neurocristopathies, such as Hirchsprung's disease. A mutation in the PHOX2B gene has recently been identified. In a family of both parents and five offspring, detailed clinical assessment, pulmonary function testing, overnight sleep studies and ventilatory responsiveness to progressive hypercapnia (V'(R,CO(2))) were performed, in addition to analysis of known genetic loci for this condition. The father and four of the offspring demonstrated features of central hypoventilation with nonapnoeic oxygen desaturation during sleep and diminished V'(R,CO(2)), despite normal pulmonary function. The lowest sleep saturation was median (range) 79% (67-83%) and V'(R,CO(2)) was 2.1 (0.03-4.3) L x min(-1) x kPa(-1). The normal values for the authors' centre (St Vincent's University Hospital, Dublin, Ireland) are 15-40 L x min(-1) x kPa(-1). An in-frame five amino acid polyalanine expansion of the PHOX2B gene was found in all affected subjects, while the mother and fifth child, who did not have features of central hypoventilation, had a normal PHOX2B gene. Magnetic resonance imaging of the brainstem in one severely affected child was normal. The present study of a unique family confirms that transmission of late-onset congenital central hypoventilation syndrome is autosomal dominant in nature.

Prevalence of sexually transmitted infections and mental health needs of female child and adolescent survivors of rape and sexual assault attending a specialist clinic

OBJECTIVES

To determine the prevalence of sexually transmitted infections (STIs) and the mental health needs of female child and adolescent survivors of rape and sexual assault who were referred to a specialist genitourinary medicine (GUM) clinic.

METHOD

Retrospective case notes review of 98 females aged 16 or less, who attended over a 5 year period (1996-2000).

RESULTS

The overall prevalence of STIs was 26%. Among the girls who were aged 0-12 years (n = 16), one had gonorrhoea and another had Trichomonas vaginalis infection. Prevalence of STIs in those aged 13-16 years, who were not sexually active before the index assault, was 24% and in those who gave a history of previous consensual sexual activity it was 39% (p = 0.17). Chlamydial infection was more common among the girls who disclosed previous consensual sexual activity than in those did not disclose previous sexual activity (p = 0.012). The overall prevalence of vaginal candidiasis was 17% and bacterial vaginosis 13%. More than one third of the study population gave a history of previous sexual, physical, or other abuse. 81% reported having current psychological difficulties. Mood changes and sleep disturbances were reported more frequently than other psychological symptoms; 15% attempted self harm. All types of psychological difficulties, except mood changes, were not affected by the time interval between index assault and first presentation to the clinic and the type of assailant. 29% had no involvement with social and mental health services before their attendance at the clinic

CONCLUSIONS

The prevalence of STIs among female child and adolescent survivors of rape and sexual assault attending a specialist clinic was high. The range of mental health and social difficulties was wide and multiple. The importance of an early assessment for the presence of STIs and mental health difficulties was demonstrated.

Male and female C57BL/6 mice respond differently to diazepam challenge in avoidance learning tasks

Benzodiazepines (BZ) impair learning and memory performance of animals. The goal of this study was to examine sex differences in the effects of diazepam on learning and memory of C57BL/6 mice in avoidance paradigms. Male and female C57BL/6 mice were tested in the one-way active avoidance, step-down passive avoidance, and foot-shock pain threshold tasks, following administration of vehicle or diazepam (1 mg/kg). No substantial sex or drug effects on the threshold of the pain response to shock were found. There were no significant differences in avoidance performance between vehicle-treated male and female mice while 1 mg/kg of diazepam produced opposite effects on performance of males and females in both tasks. Diazepam-treated females learned faster in the active avoidance task and showed stronger retention in the passive avoidance task. In contrast, diazepam impaired learning of males in the active avoidance task and had no effect on their performance in the passive avoidance task. Diazepam-induced impairment in males was not due to higher sensitivity to the sedative effect of diazepam as females were more sedated than males on the first trial of the passive avoidance task. Our data showed that sedative and amnesic effects of BZs are not tightly linked. This study also suggests that cognitive effects of BZs in rodents could be sex dependent and highlight the importance of using both sexes in studies on behavioral effects of psychoactive drugs.

Homeless patients' experience of satisfaction with care

This article explores homeless individuals' experiences of satisfaction with health care, and explores the interrelationship among experiences of being homeless, health perceptions of participants, and experiences of satisfaction with health care. It presents the findings of a phenomenological study that was conducted using participants selected from five sites in one southeastern state. Participant interviews were conducted at a nurse-managed primary health care clinic for homeless, at a night time soup-kitchen, and at three private, not-for-profit, homeless shelters in two different towns. The study was part of a larger study designed to develop and validate a reliable measure of client satisfaction with primary health care among homeless individuals. Face-to-face in-depth interviews with 17 homeless individuals were conducted, with the semistructured interview constituting the primary data source. Common themes were identified and the interrelationship of theme clusters was explored. Analysis of the data yielded five distinct themes that represent the lived experiences of satisfaction with health care. These themes were mediated and directly informed by five themes of homelessness and three themes of health identified in the shared experiences of the participants. The themes identified suggest that satisfaction with health care for homeless persons differs from currently identified dimensions of satisfaction with care, and that some aspects of homelessness are seen by participants as positive and health promoting.

Rapid detox: understanding new treatment approaches for the addicted patient

TOPIC

Despite substantive advances in understanding of genetic and biochemical basis of substance abuse and addiction in the last decade, little information has been translated into alternative treatment models for the addicted patient. Rapid detox, an alternative form of detox treatment, is gaining in both acceptance and popularity.

PURPOSE

To increase readers' understanding of the neurobiology of addiction and the mode of action of new detox approaches for patients addicted to opiate drugs.

SOURCES

A review of the current literature pertaining to rapid detox.

CONCLUSIONS

Rapid detox is a viable alternative for selected patients attempting to detox from opiate agents of abuse. Increasing knowledge of new treatment approaches allows nurses working to assist addicted patients in planning and receiving treatment based on new awareness of the neurobiology of addiction.

APRIL and TALL-I and receptors BCMA and TACI: system for regulating humoral immunity

We report that the tumor neurosis factor homolog APRIL (a proliferation-inducing ligand) stimulates in vitro proliferation of primary B and T cells and increases spleen weight due to accumulation of B cells in vivo. APRIL functions via binding to BCMA (B cell maturation antigen) and TACI (transmembrane activator and CAML-interactor) and competes with TALL-I (also called BLyS or BAFF) for receptor binding. Soluble BCMA and TACI specifically prevent binding of APRIL and block APRIL-stimulated proliferation of primary B cells. BCMA-Fc also inhibits production of antibodies against keyhole limpet hemocyanin and Pneumovax in mice, indicating that APRIL and/or TALL-I signaling via BCMA and/or TACI are required for generation of humoral immunity. Thus, APRIL-TALL-I and BCMA-TACI form a two ligands-two receptors pathway involved in stimulation of B and T cell function.

Bringing psychiatric nursing into the twenty-first century

Psychiatric nursing stands at a crossroads, in danger of losing both its identity and standing within the larger body of nursing. Enrollment in graduate programs is at an all time low and many traditional employment opportunities for psychiatric nurses are disappearing. Many explanations have been proposed to account for the crisis in psychiatric nursing practice. Although many of the identified external forces have had real impact on psychiatric nursing, these factors have impacted all of nursing. Yet our Nurse Practitioner (NP) peers are thriving, with proliferation of NP programs with unprecedented enrollment for this nationally accepted and understood role. The psychiatric nursing crisis may be most directly related to the reality that we as a professional group have thus far failed to adequately respond to external realities that have dramatically altered the environment in which psychiatric nursing occurs. This article argues for reframing the discipline of psychiatric nursing, accomplished as a national consensus building process, and including 4 critical components: (1) reconceptualization of what constitutes the core of psychiatric nursing content and represents the epistemological heart of the profession; (2) identification of the critical clinical competencies that reflect the core content, represent the role and scope of psychiatric nursing, and that match current and anticipated practice realities; (3) identification and standardization of measurable clinical outcomes, predicated on both content and competencies, which will allow psychiatric nurses to measure, in meaningful ways, the impact of their practice on patients' health; and (4) establishment of a research agenda that will allow psychiatric nursing to expand its unique knowledge base.

Severe B cell hyperplasia and autoimmune disease in TALL-1 transgenic mice

TALL-1/Blys/BAFF is a member of the tumor necrosis factor (TNF) ligand superfamily that is functionally involved in B cell proliferation. Here, we describe B cell hyperplasia and autoimmune lupus-like changes in transgenic mice expressing TALL-1 under the control of a beta-actin promoter. The TALL-1 transgenic mice showed severe enlargement of spleen, lymph nodes, and Peyer's patches because of an increased number of B220+ cells. The transgenic mice also had hypergammaglobulinemia contributed by elevations of serum IgM, IgG, IgA, and IgE. In addition, a phenotype similar to autoimmune lupus-like disease was also seen in TALL-1 transgenic mice, characterized by the presence of autoantibodies to nuclear antigens and immune complex deposits in the kidney. Prolonged survival and hyperactivity of transgenic B cells may contribute to the autoimmune lupus-like phenotype in these animals. Our studies further confirm TALL-1 as a stimulator of B cells that affect Ig production. Thus, TALL-1 may be a primary mediator in B cell-associated autoimmune diseases.

Congenital anomalies in patients with Duane retraction syndrome and their relatives

PURPOSE

Although the high incidence of skeletal, neural, and other ocular problems has been identified in previous reports of large cohorts of patients with Duane syndrome, there has not been any documentation of anomalies in close relatives. Patients with Duane syndrome have a greater than 50% incidence of associated abnormalities that include deafness, other ocular anomalies, cranial nerve palsies, and skeletal abnormalities. This study was undertaken to review the experience of our strabismus service with patients who have Duane retraction syndrome (DRS) and to delineate the associated anomalies in them and their first-degree relatives.

METHODS

A prospective study of all patients with Duane syndrome who were seen at the strabismus service at Moorfields Eye Hospital has been ongoing for the last 4 years. All patients were assessed for the presence of ophthalmologic features of DRS and then referred to the pediatric service for a physical and neurologic examination. First-degree relatives were also examined, and a family pedigree was generated.

RESULTS

We have evaluated 68 patients with DRS, of which 60.2% were female patients. The left eye was involved at a ratio of 4:1 in unilateral cases. The number of bilateral cases was 57.3%. Among the patients with DRS, 46% had first-degree relatives with associated abnormalities.

CONCLUSIONS

The high incidence of associated anomalies in patients and first-degree relatives may suggest that a common genetic defect is responsible. This has to be confirmed with molecular genetic studies, which were not performed on these families because of a lack of available resources. However, our findings may indicate that the inheritance of Duane syndrome is much higher than the 10% previously reported, if any congenital abnormality is accepted as DRS associated. Children with Duane syndrome may benefit from a full medical assessment, in view of the frequency of other abnormalities, and so may their siblings.

RANK is the intrinsic hematopoietic cell surface receptor that controls osteoclastogenesis and regulation of bone mass and calcium metabolism

We have generated RANK (receptor activator of NF-kappaB) nullizygous mice to determine the molecular genetic interactions between osteoprotegerin, osteoprotegerin ligand, and RANK during bone resorption and remodeling processes. RANK(-/-) mice lack osteoclasts and have a profound defect in bone resorption and remodeling and in the development of the cartilaginous growth plates of endochondral bone. The osteopetrosis observed in these mice can be reversed by transplantation of bone marrow from rag1(-/-) (recombinase activating gene 1) mice, indicating that RANK(-/-) mice have an intrinsic defect in osteoclast function. Calciotropic hormones and proresorptive cytokines that are known to induce bone resorption in mice and human were administered to RANK(-/-) mice without inducing hypercalcemia, although tumor necrosis factor alpha treatment leads to the rare appearance of osteoclast-like cells near the site of injection. Osteoclastogenesis can be initiated in RANK(-/-) mice by transfer of the RANK cDNA back into hematopoietic precursors, suggesting a means to critically evaluate RANK structural features required for bone resorption. Together these data indicate that RANK is the intrinsic cell surface determinant that mediates osteoprotegerin ligand effects on bone resorption and remodeling as well as the physiological and pathological effects of calciotropic hormones and proresorptive cytokines.

Activated T cells regulate bone loss and joint destruction in adjuvant arthritis through osteoprotegerin ligand

Bone remodelling and bone loss are controlled by a balance between the tumour necrosis factor family molecule osteoprotegerin ligand (OPGL) and its decoy receptor osteoprotegerin (OPG). In addition, OPGL regulates lymph node organogenesis, lymphocyte development and interactions between T cells and dendritic cells in the immune system. The OPGL receptor, RANK, is expressed on chondrocytes, osteoclast precursors and mature osteoclasts. OPGL expression in T cells is induced by antigen receptor engagement, which suggests that activated T cells may influence bone metabolism through OPGL and RANK. Here we report that activated T cells can directly trigger osteoclastogenesis through OPGL. Systemic activation of T cells in vivo leads to an OPGL-mediated increase in osteoclastogenesis and bone loss. In a T-cell-dependent model of rat adjuvant arthritis characterized by severe joint inflammation, bone and cartilage destruction and crippling, blocking of OPGL through osteoprotegerin treatment at the onset of disease prevents bone and cartilage destruction but not inflammation. These results show that both systemic and local T-cell activation can lead to OPGL production and subsequent bone loss, and they provide a novel paradigm for T cells as regulators of bone physiology.

Psychiatric nurse practitioner versus clinical nurse specialist: moving from debate to action on the future of advanced psychiatric nursing

The psychiatric nursing literature recently has included a proliferation of discussions regarding the nature and direction of change impacting the future of advanced practice psychiatric nursing. The debate has focused most commonly on the role of the clinical nurse specialist versus the role of the nurse practitioner. The debate has produced little in the way of outcomes other than an entrenchment of positions. The stalemate in psychiatric nursing is producing a slow but steady surrender of the boundaries of psychiatric nursing to other fields of nursing. Although advanced practice psychiatric nurses disagree on what to become and what to be called, people with conditions such as depression, anxiety disorders, and other psychiatric disorders are being treated increasingly by family nurse practitioners. The time for debate has ended. Unless consensus regarding what constitutes the domain of psychiatric nursing is reached soon, the discussions will be moot because few clients will remain to be treated. This article began as a discussion between colleagues. The two authors teach at a regional state university, but they share diverse opinions regarding the substance and nature of advanced practice psychiatric nursing. These diverse views led to discussions that have implications not only for faculty practice, but for curricular design, and for decisions regarding how to best educate future nurses. The discussion developed into a presentation at the 20th Southeast Conference of Clinical Nurse Specialists. It was presented as a point-counterpoint discussion regarding this debate; one author advocated the perspective of traditional clinical nurse specialist and one advocated the perspective of a psychiatric nurse practitioner role. We conclude with a projected model of a merged role, with delineation of traditional clinical nurse specialist and nurse practitioner that must be blended for the new role.

Humanization of an anti-lymphocyte function-associated antigen (LFA)-1 monoclonal antibody and reengineering of the humanized antibody for binding to rhesus LFA-1

Lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18) is involved in leukocyte adhesion during cellular interactions essential for immunologic responses and inflammation. mAbs against LFA-1 have been shown to inhibit several T cell-dependent immune functions in vitro and prevent graft failure after bone marrow transplantation in vivo. A murine anti-human CD11a mAb, MHM24, has been humanized and shown to prevent adhesion of human T cells to human keratinocytes and the proliferation of T cells in response to nonautologous leukocytes in the mixed lymphocyte response assay. However, of the nonhuman primate CD11a that we tested, the murine and humanized mAbs cross-reacted only with chimpanzee CD11a. To have a mAb available for preclinical studies in rhesus monkeys, the humanized mAb was reengineered to bind to rhesus CD11a by changing four residues in one of the complementarity-determining regions, CDR-H2, in the variable heavy domain. Cloning and molecular modeling of rhesus CD11a I-domain suggested that the changes from Lys197 and/or Arg189 in human CD11a I-domain to Glu197 and Gln189 in rhesus CD11a I-domain may be the reason that rhesus CD11a does not bind to the murine and humanized mAbs.

Humanization of an anti-lymphocyte function-associated antigen (LFA)-1 monoclonal antibody and reengineering of the humanized antibody for binding to rhesus LFA-1

Lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18) is involved in leukocyte adhesion during cellular interactions essential for immunologic responses and inflammation. mAbs against LFA-1 have been shown to inhibit several T cell-dependent immune functions in vitro and prevent graft failure after bone marrow transplantation in vivo. A murine anti-human CD11a mAb, MHM24, has been humanized and shown to prevent adhesion of human T cells to human keratinocytes and the proliferation of T cells in response to nonautologous leukocytes in the mixed lymphocyte response assay. However, of the nonhuman primate CD11a that we tested, the murine and humanized mAbs cross-reacted only with chimpanzee CD11a. To have a mAb available for preclinical studies in rhesus monkeys, the humanized mAb was reengineered to bind to rhesus CD11a by changing four residues in one of the complementarity-determining regions, CDR-H2, in the variable heavy domain. Cloning and molecular modeling of rhesus CD11a I-domain suggested that the changes from Lys197 and/or Arg189 in human CD11a I-domain to Glu197 and Gln189 in rhesus CD11a I-domain may be the reason that rhesus CD11a does not bind to the murine and humanized mAbs.

The seven deadly sins of statistical analysis

In a pedantic but playful way, we discuss some common errors in the use of 'statistical analysis' that are regularly observed in our professional plastic surgical literature. The seven errors we discuss are (1) the use of parametric analysis of ordinal data; (2) the inappropriate use of parametric analysis in general; (3) the failure to consider the possibility of committing type II statistical error; (4) the use of unmodified t-tests for multiple comparisons; (5) the failure to employ analysis of covariance, multivariate regression, nonlinear regression, and logistical regression when indicated; (6) the habit of reporting standard error instead of standard deviation; and (7) the underuse or overuse of statistical consultation. Confidence and common sense are advocated as a means to balance statistical significance with clinical importance.

Changing roles of consumer/survivors in mature mental health systems

It is useful to have a framework for involving consumer/survivors of mental health services. Through practical examples, barriers to consumer/survivor involvement and strategies for increasing involvement are identified and discussed.

Immunological effects of insulin-like growth factor-I--enhancement of immunoglobulin synthesis

In addition to its activity as a metabolic hormone and a regulator of somatic growth, insulin-like growth factor-I (IGF-I) has cytokine-like activities on lymphoid cells. A 14-day infusion of recombinant human (rh)IGF-I increased lymphocyte numbers in all the peripheral lymphoid organs examined. This increase was apparent for up to 3 weeks following cessation of hormone treatment. A second administration of rhIGF-I, given when the lymphocyte numbers in the rhIGF-I-treated mice had returned to control values, resulted in similar increases in the peripheral T and B cell populations. This increase in lymphocyte numbers had functional significance, since rhIGF-I-treated mice produced elevated antibody titres following primary or secondary antigen challenge compared with controls. In addition, when rhIGF-I-treated mice were immunized with a suboptimal dose of antigen they produced antibody titres which were equivalent to those generated by immunization with optimal doses of antigen. When examined in vitro, addition of rhIGF-I alone to cultures of splenocytes from antigen-primed mice stimulated immunoglobulin synthesis. These studies suggest that IGF-I produced locally by thymic and bone marrow stromal cells may be a natural component of B and T cell lymphopoiesis.

Recipient vessels in head and neck microsurgery: radiation effect and vessel access

Historical cohort analysis compared free-flap survival rates in 226 irradiated and 108 nonirradiated head and neck reconstructions. The failure rate for the irradiated flaps (3.5 percent) did not differ significantly from that for the nonirradiated group (2.9 percent). A case-control study of the failed irradiated flaps revealed infection and lag time between radiotherapy and surgery as the only factors significantly associated with free flap failure. Salvage techniques (vein grafting, cephalic transposition, and Corlett looping) for recruiting recipient vessels into radically ablated head and neck beds are reviewed.