Masseter muscle volume as a disease marker in adult-onset myotonic dystrophy type 1

The advent of clinical trials in myotonic dystrophy type 1 (DM1) necessitates the identification of reliable outcome measures to quantify different disease manifestations using minimal number of assessments. In this study, clinical correlations of mean masseter volume (mMV) were explored to evaluate its potential as a marker of muscle involvement in adult-onset DM1 patients. We utilised data from a preceding study, pertaining to 39 DM1 patients and 20 age-matched control participants. In this study participants had undergone MRI of the brain, completed various clinical outcome measures and had CTG repeats measured by small-pool PCR. Manual segmentation of masseter muscles was performed by a single rater to estimate mMV. The masseter muscle was atrophied in DM1 patients when compared to controls (p<0.001). Significant correlations were found between mMV and estimated progenitor allele length (p = 0.001), modal allele length (p = 0.003), disease duration (p = 0.009) and and the Muscle Impairment Rating Scale (p = 0.008). After correction for lean body mass, mMV was also inversely correlated with self-reported myotonia (p = 0.014). This study demonstrates that changes in mMV are sensitive in reflecting the underlying disease process. Quantitative MRI methods demonstrate that data concerning both central and peripheral disease could be acquired from MR brain imaging studies in DM1 patients.

Genomic and phenotypic characterization of 404 individuals with neurodevelopmental disorders caused by CTNNB1 variants

PURPOSE

Germline loss-of-function variants in CTNNB1 cause neurodevelopmental disorder with spastic diplegia and visual defects (NEDSDV; OMIM 615075) and are the most frequent, recurrent monogenic cause of cerebral palsy (CP). We investigated the range of clinical phenotypes owing to disruptions of CTNNB1 to determine the association between NEDSDV and CP.

METHODS

Genetic information from 404 individuals with collectively 392 pathogenic CTNNB1 variants were ascertained for the study. From these, detailed phenotypes for 52 previously unpublished individuals were collected and combined with 68 previously published individuals with comparable clinical information. The functional effects of selected CTNNB1 missense variants were assessed using TOPFlash assay.

RESULTS

The phenotypes associated with pathogenic CTNNB1 variants were similar. A diagnosis of CP was not significantly associated with any set of traits that defined a specific phenotypic subgroup, indicating that CP is not additional to NEDSDV. Two CTNNB1 missense variants were dominant negative regulators of WNT signaling, highlighting the utility of the TOPFlash assay to functionally assess variants.

CONCLUSION

NEDSDV is a clinically homogeneous disorder irrespective of initial clinical diagnoses, including CP, or entry points for genetic testing.

Clinical and neuroradiological correlates of sleep in myotonic dystrophy type 1

Abnormalities of sleep are common in myotonic dystrophy type 1 (DM1), but few previous studies have combined polysomnography with detailed clinical measures and brain imaging. In the present study, domiciliary polysomnography, symptom questionnaires and cognitive evaluation were undertaken in 39 DM1-affected individuals. Structural brain MRI was completed in those without contra-indication (n = 32). Polysomnograms were adequate for analysis in 36 participants. Sleep efficiency was reduced, and sleep architecture altered in keeping with previous studies. Twenty participants (56%) had moderate or severe sleep-disordered breathing (apnoea-hypopnoea index [AHI] ≥ 15). In linear modelling, apnoeas were positively associated with increasing age and male sex. AHI ≥ 15 was further associated with greater daytime pCO₂ and self-reported physical impairment, somnolence and fatigue. Percentage REM sleep was inversely associated with cerebral grey matter volume, stage 1 sleep was positively associated with occipital lobe volume and stage 2 sleep with amygdala volume. Hippocampus volume was positively correlated with self-reported fatigue and somnolence. Linear relationships were also observed between measures of sleep architecture and cognitive performance. Findings broadly support the hypothesis that changes in sleep architecture and excessive somnolence in DM1 reflect the primary disease process in the central nervous system.

Range and Frequency of Congenital Malformations Among Children With Cleft Lip and/or Palate

To assess the range and frequency of additional congenital malformations identified among children born alive with CL/P.

Analysis of patient-level data from a national registry of cleft births linked to national administrative data of hospital admissions.

National Health Service, England.

Children born between 2000 and 2012 receiving cleft care in English NHS hospitals.

The proportion of children with ICD-10 codes for additional congenital malformations, according to cleft type.

The study included 9403 children. Of these 2114 (22.5%) had CL±A, 4509 (48.0%) had CP, 1896 (20.2%) had UCLP, and 884 (9.4%) had BCLP. A total of 3653 (38.8%) children had additional congenital malformations documented in their hospital admission records. The prevalence of additional congenital malformations was greatest among children with CP (53.0%), followed by those with BCLP (33.5%), UCLP (26.3%), and then CL±A (22.2%) (P < .001). Among those with UCLP, children with right-sided clefts were more likely to have additional malformations than those with left-sided clefts (31.6% vs 23.0%, P < .001). Malformations of the skeletal system and circulatory system were most common, affecting 10.5% and 10.2% of the included children, respectively. A total of 16.8% of children had additional congenital malformations affecting 2 or more structural systems.

Congenital malformations are common among children born alive with a cleft, affecting over half of some cleft subgroups. Given the frequency of certain structural malformations, clinicians should consider standardized screening for these children. Establishing good links with pediatric and genetic services is recommended.

Brain Structural Features of Myotonic Dystrophy Type 1 and their Relationship with CTG Repeats

Background

Few adequately-powered studies have systematically evaluated brain morphology in adult-onset myotonic dystrophy type 1 (DM1).

Objective

The goal of the present study was to determine structural brain differences between individuals with and without adult-onset DM1 in a multi-site, case-controlled cohort. We also explored correlations between brain structure and CTG repeat length.

Methods

Neuroimaging data was acquired in 58 unaffected individuals (29 women) and 79 individuals with DM1 (50 women). CTG repeat length, expressed as estimated progenitor allele length (ePAL), was determined by small pool PCR. Statistical models were adjusted for age, sex, site, and intracranial volume (ICV).

Results

ICV was reduced in DM1 subjects compared with controls. Accounting for the difference in ICV, the DM1 group exhibited smaller volume in frontal grey and white matter, parietal grey matter as well as smaller volume of the corpus callosum, thalamus, putamen, and accumbens. In contrast, volumes of the hippocampus and amygdala were significantly larger in DM1. Greater ePAL was associated with lower volumes of the putamen, occipital grey matter, and thalamus. A positive ePAL association was observed for amygdala volume and cerebellar white matter.

Conclusions

Smaller ICV may be a marker of aberrant neurodevelopment in adult-onset DM1. Volumetric analysis revealed morphological differences, some associated with CTG repeat length, in structures with plausible links to key DM1 symptoms including cognitive deficits and excessive daytime somnolence. These data offer further insights into the basis of CNS disease in DM1, and highlight avenues for further work to identify therapeutic targets and imaging biomarkers.

The prevalence of faecal incontinence in myotonic dystrophy type 1

Faecal incontinence is recognised as a feature of myotonic dystrophy along with other symptoms of bowel dysfunction, but its prevalence is poorly defined. We have surveyed 152 unselected myotonic dystrophy patients. We identified issues with bowel control in 104 (68% of the study population). Forty-eight (32%) reported faecal incontinence in the 4 weeks prior to completion of the questionnaire. Fifty-six patients (37%) reported having to change their lifestyle because of incontinence issues at some point in the prior 4 weeks. This study shows a high frequency of life-changing symptoms in a large unselected, cohort of patients with myotonic dystrophy type 1, and highlights lower gastrointestinal symptoms as an important issue for further research.

De novo repeat interruptions are associated with reduced somatic instability and mild or absent clinical features in myotonic dystrophy type 1

Myotonic dystrophy type 1 (DM1) is a multisystem disorder, caused by expansion of a CTG trinucleotide repeat in the 3'-untranslated region of the DMPK gene. The repeat expansion is somatically unstable and tends to increase in length with time, contributing to disease progression. In some individuals, the repeat array is interrupted by variant repeats such as CCG and CGG, stabilising the expansion and often leading to milder symptoms. We have characterised three families, each including one person with variant repeats that had arisen de novo on paternal transmission of the repeat expansion. Two individuals were identified for screening due to an unusual result in the laboratory diagnostic test, and the third due to exceptionally mild symptoms. The presence of variant repeats in all three expanded alleles was confirmed by restriction digestion of small pool PCR products, and allele structures were determined by PacBio sequencing. Each was different, but all contained CCG repeats close to the 3'-end of the repeat expansion. All other family members had inherited pure CTG repeats. The variant repeat-containing alleles were more stable in the blood than pure alleles of similar length, which may in part account for the mild symptoms observed in all three individuals. This emphasises the importance of somatic instability as a disease mechanism in DM1. Further, since patients with variant repeats may have unusually mild symptoms, identification of these individuals has important implications for genetic counselling and for patient stratification in DM1 clinical trials.

Outcome Measures for Central Nervous System Evaluation in Myotonic Dystrophy Type 1 May Be Confounded by Deficits in Motor Function or Insight

Background: Central nervous system involvement in myotonic dystrophy type 1 (DM1) is associated with cognitive deficits, impaired social performance and excessive somnolence, which greatly impact quality of life. With the advent of clinical trials in DM1, there is a pressing need to identify outcome measures for quantification of central symptoms that are feasible and valid. In this context, we sought to evaluate neuropsychological and self-reported measures currently recommended by expert consensus, with particular reference to their specificity for central nervous system involvement in a moderate-sized DM1 cohort.

Methods: Forty-five adults with DM1 and 20 controls completed neuropsychology assessments and symptom questionnaires. Those without contraindication also underwent MRI brain, from which global gray matter volume and white matter lesion volume were quantified. CTG repeat was measured by small pool PCR, and was screened for the presence of variant repeat sequences.

Results: The neuropsychology test battery was well tolerated and detected impairment across various domains in the DM1 group vs. controls. Large effect sizes in the Stroop and Trail Making Tests were however attenuated by correction for basic speed, which could be influenced by dysarthria and upper limb weakness, respectively. Low mood was strongly associated with increased self-reporting of central symptoms, including cognitive impairment. Conversely, self-reported cognitive impairment did not generally predict poorer performance in neuropsychology assessments, and there was a trend toward greater self-reporting of low mood and cognitive problems in those with milder white matter change on MRI. Global gray matter volume correlated with performance in several neuropsychology assessments in a multivariate model with age and sex, while white matter lesion volume was associated with executive dysfunction reported by a proxy. Screening for variant repeats was positive in three individuals, who reported mild muscle symptoms.

Conclusions: Identification of outcome measures with good specificity for brain involvement in DM1 is challenging, since complex cognitive assessments may be compromised by peripheral muscle weakness and self-reported questionnaires may be influenced by mood and insight. This highlights the need for further large, longitudinal studies to identify and validate objective measures, which may include imaging biomarkers and cognitive measures not influenced by motor speed.

Heterozygous mutations affecting the protein kinase domain of CDK13 cause a syndromic form of developmental delay and intellectual disability

Introduction

Recent evidence has emerged linking mutations in CDK13 to syndromic congenital heart disease. We present here genetic and phenotypic data pertaining to 16 individuals with CDK13 mutations.

Methods

Patients were investigated by exome sequencing, having presented with developmental delay and additional features suggestive of a syndromic cause.

Results

Our cohort comprised 16 individuals aged 4–16 years. All had developmental delay, including six with autism spectrum disorder. Common findings included feeding difficulties (15/16), structural cardiac anomalies (9/16), seizures (4/16) and abnormalities of the corpus callosum (4/11 patients who had undergone MRI). All had craniofacial dysmorphism, with common features including short, upslanting palpebral fissures, hypertelorism or telecanthus, medial epicanthic folds, low-set, posteriorly rotated ears and a small mouth with thin upper lip vermilion. Fifteen patients had predicted missense mutations, including five identical p.(Asn842Ser) substitutions and two p.(Gly717Arg) substitutions. One patient had a canonical splice acceptor site variant (c.2898–1G>A). All mutations were located within the protein kinase domain of CDK13. The affected amino acids are highly conserved, and in silico analyses including comparative protein modelling predict that they will interfere with protein function. The location of the missense mutations in a key catalytic domain suggests that they are likely to cause loss of catalytic activity but retention of cyclin K binding, resulting in a dominant negative mode of action. Although the splice-site mutation was predicted to produce a stable internally deleted protein, this was not supported by expression studies in lymphoblastoid cells. A loss of function contribution to the underlying pathological mechanism therefore cannot be excluded, and the clinical significance of this variant remains uncertain.

Conclusions

These patients demonstrate that heterozygous, likely dominant negative mutations affecting the protein kinase domain of the CDK13 gene result in a recognisable, syndromic form of intellectual disability, with or without congenital heart disease.

Maraviroc decreases CCL8-mediated migration of CCR5(+) regulatory T cells and reduces metastatic tumor growth in the lungs

Regulatory T cells (Tregs) play a crucial physiological role in the regulation of immune homeostasis, although recent data suggest Tregs can contribute to primary tumor growth by suppressing antitumor immune responses. Tregs may also influence the development of tumor metastases, although there is a paucity of information regarding the phenotype and function of Tregs in metastatic target organs. Herein, we demonstrate that orthotopically implanted metastatic mammary tumors induce significant Treg accumulation in the lungs, which is a site of mammary tumor metastasis. Tregs in the primary tumor and metastatic lungs express high levels of C-C chemokine receptor type 5 (CCR5) relative to Tregs in the mammary fat pad and lungs of tumor-free mice, and Tregs in the metastatic lungs are enriched for CCR5 expression in comparison to other immune cell populations. We also identify that C-C chemokine ligand 8 (CCL8), an endogenous ligand of CCR5, is produced by F4/80(+) macrophages in the lungs of mice with metastatic primary tumors. Migration of Tregs toward CCL8 ex vivo is reduced in the presence of the CCR5 inhibitor Maraviroc. Importantly, treatment of mice with Maraviroc (MVC) reduces the level of CCR5(+) Tregs and metastatic tumor burden in the lungs. This work provides evidence of a CCL8/CCR5 signaling axis driving Treg recruitment to the lungs of mice bearing metastatic primary tumors, representing a potential therapeutic target to decrease Treg accumulation and metastatic tumor growth.

Questionnaire-based assessment of owner concerns and doctor responsiveness: 107 canine chemotherapy patients

OBJECTIVE

To quantify owner concerns regarding clinical signs in canine patients receiving chemotherapy and to assess degree of concordance between client and veterinarian concerns regarding patient quality of life.

METHODS

Retrospective analysis of owner-reported concerns during chemotherapy treatment. Owner-reported adverse events were recorded sequentially for each patient through a partially open design questionnaire and correlated with veterinary patient summaries for each visit. Canine patients treated for transitional cell carcinoma, haemangiosarcoma, malignant melanoma or osteosarcoma were eligible for inclusion. Minimum treatment eligibility was two chemotherapy treatments given in 21-day protocol cycles, with a maximum of six treatment cycles recorded.

RESULTS

A total of 553 evaluable visits, seen by 18 oncology clinicians, were assessed. Owners expressed concern before chemotherapy in 48% of visits. Owner concerns at the first visit did not differ significantly from those expressed at the sixth visit. Remission status was a significant factor in owners' rate of reporting concerns. Diarrhoea grade was associated with owners' concerns. Clinician gender was not associated with responsiveness to owners' concerns.

CLINICAL SIGNIFICANCE

Questionnaire-based surveys appear to be an effective tool for communicating dog owners' concerns regarding chemotherapy and potentially for monitoring a clinician's attentiveness. Owners expressed concerns at approximately half of chemotherapy appointments.

Mediators of antiretroviral adherence: a multisite international study

The purpose of this study was to investigate the effects of stressful life events (SLE) on medication adherence (3 days, 30 days) as mediated by sense of coherence (SOC), self-compassion (SCS), and engagement with the healthcare provider (eHCP) and whether this differed by international site. Data were obtained from a cross-sectional sample of 2082 HIV positive adults between September 2009 and January 2011 from sites in Canada, China, Namibia, Puerto Rico, Thailand, and US. Statistical tests to explore the effects of stressful life events on antiretroviral medication adherence included descriptive statistics, multivariate analysis of variance, analysis of variance with Bonferroni post-hoc analysis, and path analysis. An examination by international site of the relationships between SLE, SCS, SOC, and eHCP with adherence (3 days and 30 days) indicated these combined variables were related to adherence whether 3 days or 30 days to different degrees at the various sites. SLE, SCS, SOC, and eHCP were significant predictors of adherence past 3 days for the United States (p = < 0.001), Canada (p = 0.006), and Namibia (p = 0.019). The combined independent variables were significant predictors of adherence past 30 days only in the United States and Canada. Engagement with the provider was a significant correlate for antiretroviral adherence in most, but not all, of these countries. Thus, the importance of eHCP cannot be overstated. Nonetheless, our findings need to be accompanied by the caveat that research on variables of interest, while enriched by a sample obtained from international sites, may not have the same relationships in each country.

Prevalence, correlates, and self-management of HIV-related depressive symptoms

Depressive symptoms are highly prevalent yet undertreated in people living with HIV/AIDS (PLHAs). As part of a larger study of symptom self-management (N=1217), this study examined the prevalence, correlates, and characteristics (intensity, distress, and impact) of depressive symptoms, and the self-care strategies used to manage those symptoms in PLHAs in five countries. The proportion of respondents from each country in the total sample reporting depressive symptoms in the past week varied and included Colombia (44%), Norway (66%), Puerto Rico (57%), Taiwan (35%), and the USA (56%). Fifty-four percent (n=655) of the total sample reported experiencing depressive symptoms in the past week, with a mean of 4.1 (SD 2.1) days of depression. Mean depression intensity 5.4 (SD 2.7), distressfulness 5.5 (SD 2.86), and impact 5.5 (SD 3.0) were rated on a 1-10 scale. The mean Center for Epidemiologic Studies Depression Scale score for those reporting depressive symptoms was 27 (SD 11; range 3-58), and varied significantly by country. Respondents identified 19 self-care behaviors for depressive symptoms, which fell into six categories: complementary therapies, talking to others, distraction techniques, physical activity, medications, and denial/avoidant coping. The most frequently used strategies varied by country. In the US sample, 33% of the variance in depressive symptoms was predicted by the combination of education, HIV symptoms, psychological and social support, and perceived consequences of HIV disease.

HIV illness representation as a predictor of self-care management and health outcomes: a multi-site, cross-cultural study

Research has shown that the perceptions that form the cognitive representation of an illness (illness representation) are fundamental to how persons cope with illness. This study examined the relationship of illness representation of HIV with self-care behavior and health outcomes. Data were collected at 16 sites in the United States, Taiwan, Norway, Puerto Rico and Colombia via survey. HIV seropositive participants (n = 1,217, 31% female, 38% African-American/Black, 10% Asian/Pacific Islander and 26% White/Anglo) completed measures of illness representation based on the commonly accepted five-component structure: identity, time-line, consequences, cause, and cure/controllability (Weinman et al. 1996, Psychology and Health, 11, 431-445). Linear regression analyses were conducted to investigate relationships among illness representation, self-care behaviors and quality-of-life outcomes. Components of illness representation were associated with self-care and health outcomes, indicating that the cognitive representation of HIV has consequences for effective illness management. For example, perception that there is little that can be done to control HIV was significantly associated with fewer and less effective self-care activities (F = 12.86, P < .001) and poorer health function in the domain of quality-of-life (F = 13.89, P < .001). The concept of illness representation provides a useful framework for understanding HIV symptom management and may be useful in directing development of effective patient-centered interventions.

Unhealthy behaviours for self-management of HIV-related peripheral neuropathy

The prevalence of peripheral neuropathy is frequent in HIV disease and is often associated with antiretroviral therapy. Unhealthy behaviours, particularly substance-use behaviours, are utilized by many HIV-positive individuals to manage neuropathic symptoms. As part of a larger study on self-care for symptoms in HIV disease, this study analyzed the prevalence and characteristics of unhealthy behaviours to self-manage peripheral neuropathy in HIV disease. Sociodemographic and disease-related correlates and unhealthy behaviours were examined in a convenience sample of 1,217 respondents who were recruited from data collection sites in several US cities, Puerto Rico, Colombia, and Taiwan. Results of the study indicated that respondents with peripheral neuropathy (n=450) identified a variety of unhealthy self-care behaviours including injection drug use, oral drug use, smoking cigarettes and alcohol ingestion. Specific unhealthy behaviours that participants reported to alleviate peripheral neuropathy included use of marijuana (n=67), smoking cigarettes (n=139), drinking alcohol (n=81) and street drugs (n=30). A subset of those individuals (n=160), who identified high levels of neuropathy (greater than five on a scale of 1-10), indicated significantly higher use of amphetamines and injection drug use in addition to alcohol use and cigarette smoking. For participants from Norway, substance use (using alcohol: 56%) was one of the most frequent self-management strategies. Implications for clinical practice include assessment and education of persons with HIV for self-care management of the complex symptom of peripheral neuropathy.

Symptom management and self-care for peripheral neuropathy in HIV/AIDS

Peripheral neuropathy is the most common neurological complication in HIV and is often associated with antiretroviral therapy. As part of a larger study on self-care for symptoms in HIV disease, this study analyzed the prevalence and characteristics of peripheral neuropathy in HIV disease, sociodemographic and disease-related correlates and self-care strategies. A convenience sample of 1,217 respondents was recruited from data collection sites in several US cities, Puerto Rico, Colombia and Taiwan. Results of the study indicated that respondents with peripheral neuropathy (n=450) identified 20 self-care behaviors including complementary therapies, use of medications, exercise and rest and/or elevation of extremities. Ratings of frequency and effectiveness were also included. An activities checklist summarized into five categories of self-care behaviors including activities/thoughts, exercise, medications, complementary therapies and substance was used to determine self-care behaviors. Taking a hot bath was the most frequent strategy used by those with peripheral neuropathy (n=292) and received the highest overall rating of effectiveness of any self-management strategies included in this study at 8.1 (scale 1-10). Other self-care strategies to manage this symptom included: staying off the feet (n=258), rubbing the feet with cream (n=177), elevating the feet (n=236), walking (n=262), prescribed anti-epileptic agent (n=80), prescribed analgesics (n=84), over-the-counter medications (n=123), vitamin B (n=122), calcium supplements (n=72), magnesium (n=48), massage (n=156), acupuncture (n=43), reflexology (n=23) and meditation (n=80). Several behaviors that are often deemed unhealthy were included among the strategies reported to alleviate peripheral neuropathy including use of marijuana (n=67), cigarette smoking (n=139), drinking alcohol (n=81) and street drugs (n=30).

Immunohistochemical study of experimental malignant catarrhal fever in rabbits

Malignant catarrhal fever (MCF) is an often-fatal lymphoproliferative disease of a variety of ungulates that occurs worldwide. It is caused by either of the highly related but distinct gammaherpesviruses alcelaphine herpesvirus-1 (AlHV-1, wildebeest reservoir) or ovine herpesvirus-2 (OvHV-2, sheep reservoir). MCF in rabbits is an excellent model as it closely resembles the disease in susceptible ungulates that include cattle, deer and bison. In this study, newly available and previously characterized monoclonal antibodies specific for rabbit leucocyte differentiation molecules were used to perform a detailed immunohistochemical examination of both AlHV-1 MCF and OvHV-2 MCF in rabbits. Differences in the MCF caused by the two viruses included: less tissue necrosis and more lymphoid cell accumulations in AlHV-1 MCF compared with OvHV-2 MCF, and in particular marked tissue necrosis in the mesenteric lymph node, appendix and liver of OvHV-2-infected animals when compared with either other tissues in OvHV-2 MCF or AlHV-1 MCF lesions in any tissue. In both AlHV-1 MCF and OvHV-2 MCF, lymphoid cell accumulations in lymphoid and non-lymphoid tissues consisted mainly of T-cells with a corresponding absence of B-cells. CD8(+) T-cells accounted for a proportion of these in the non-lymphoid tissues, but there was evidence for the accumulation of an unidentified T-cell subset/subsets as well. This study extends our understanding of the mechanisms of immuno-pathogenesis of MCF.

Strategies for self-management of HIV-related anxiety

This study examines the frequency and effectiveness of commonly used strategies for self management of anxiety in an international sample of 502 participants from Norway (n=42, 8%), Taiwan (n=35, 7%), and the US (n=426, 85%). An activities checklist summarized into five categories of self-care behaviours including activities/thoughts, exercise, medications, complementary therapies, and substance use determined self-care behaviours. Ratings of frequency and effectiveness for each self-care activity were also included. Praying received the highest overall rating of effectiveness of any self-management strategies included in this study at 8.10 (scale 1 to 10), followed by meditation (7.37), exercising (7.32), using relaxation techniques (7.22), cooking (6.98), and walking (6.90). An analysis of effectiveness scores for each self-care strategy by country reflected a wide variation. The three most effective anxiety self-care strategies reported by participants from Norway included exercise (7.31), walking (6.96), and reading (6.44). Highest ratings of effectiveness by participants from Taiwan included talking with others with HIV (6.0), attending support groups (6.0), and exercising (6.0). US participants allocated highest ratings of effectiveness to complementary/alternative therapies, including praying (8.10), meditating (7.43), and using relaxation techniques (7.35). Regardless of the country, watching television and talking with family and friends were the two most frequently reported strategies. These strategies for self-management of HIV-related anxiety are important for clinicians to be aware of in the care of persons with HIV/AIDS.

The development and characterization of an HEK293-derived cell line for use in an intratumoral cytokine delivery system

As part of ongoing work to develop a method of cytokine delivery for use as an intratumoral depot, we noted that HEK293 cells, encapsulated in alginate, died within 24-48 h after in vivo, intratumoral implantation. We hypothesized that the highly hypoxic and acidic conditions found inside the tumor was the cause of the cells' premature demise. Therefore, we set out to develop a cell line, derived from HEK293, that would survive these hostile conditions. The HEK293 line was selected in 0.3-0.5% oxygen conditions over several weeks, followed by a further 6-week period of culture in alternating hypoxic and normoxic conditions. The most rapidly growing clones were selected and grown in normoxic conditions for several weeks to ensure their stability. The clones were then compared to the original line in terms of cell proliferation in normoxia and hypoxia, colony-forming efficiency, and morphological characteristics. The resulting line was able to proliferate in the harshest of conditions and continues to release its biological payload after alginate microencapsulation.

Early induction of humoral and cellular immune responses during experimental Mycobacterium avium subsp. paratuberculosis infection of calves

Johne's disease (paratuberculosis) of cattle is widespread and causes significant economic losses for producers due to decreased production and poor health of affected animals. The chronic nature of the disease and the lack of a reproducible model of infection hinder research efforts. In the present study, instillation of Mycobacterium avium subsp. paratuberculosis into the tonsillar crypts of neonatal calves resulted in peripheral colonization as detected by antemortem culture of feces and postmortem (320 days postchallenge) culture of intestinal tissues. Antigen-specific blastogenic, gamma interferon (IFN-gamma), and nitric oxide responses by blood mononuclear cells from infected calves exceeded prechallenge responses beginning 194 days postchallenge. Upon in vitro stimulation with paratuberculosis antigens, CD4(+) cells from infected calves proliferated, produced IFN-gamma, and increased expression of CD26 and CD45RO (indicative of an activated memory phenotype). Utilizing a lipoarabinomannan-based enzyme-linked immunosorbent assay, specific serum immunoglobulin was detected as early as 134 days postchallenge and generally increased after this time point. Two antigens of approximately 50 and approximately 60 kDa were particularly immunodominant early in infection, as shown by immunoblot with serum collected within 2 weeks postchallenge. Findings indicate that the intratonsillar inoculation route will prove useful as an experimental model for paratuberculosis infection. Additionally, this study confirms that mycobacteria-specific antibody is detectable early in the course of experimental Johne's disease, even preceding the development of specific cell-mediated responses.

Use of the mannan receptor to selectively target vaccine antigens for processing and antigen presentation through the MHC class I and class II pathways

Extensive studies have shown that synthetic and recombinant vaccines developed against hemoparasites have not been as effective as whole parasites or crude membrane fractions in eliciting protective immunity. A possible reason is that synthetic vaccines are not being presented in a form that induces the appropriate immune response. We have developed a bovine model system to evaluate the ability of adjuvant compounds to induce an immune response to peptide antigens dominated by a cytokine profile with a Type 1 (cell-mediated) or Type 2 (humoral) bias. In the initial testing of this system, we found that mRNA expression of certain cytokines (interleukin [IL]-1beta, IL-6, IL-12, IL-15, GM-CSF, iNOS, and tumor necrosis factor [TNF]-alpha) is enhanced when monocyte-derived macrophages are stimulated with peptide antigen conjugated with mannan under oxidizing conditions compared to peptide conjugated with reduced mannan. The data suggest this model will be useful in identifying adjuvant systems that selectively modulate the cytokine profile of antigen presenting cells at the time of antigen presentation and the consequent downstream maturation of naive T cells to effector cells with Type 1 or Type 2 cytokine bias.

Cloning of bovine CD69

CD69 is rapidly inducible on various hematopoietic cells upon stimulation and is detectable as an early activation antigen. Although CD69 is well characterized in human and mouse, no information is available on bovine CD69. We report here that, bovine CD69 was cloned from a cDNA expression library prepared from activated peripheral blood lymphocytes. The full-length cDNA contained an 80bp 5' untranslated region, followed by a 600bp coding region and AU-rich motifs in a 3' untranslated region (GenBank accession number AF272828). Comparison of the bovine CD69 coding sequence reveals 69.4 and 78.2% nucleotide sequence identities with mouse and human CD69, respectively. The predicted amino acid sequence of bovine CD69 shares 56.3 and 62.3% sequence identity when compared with mouse and human CD69, respectively. Bovine CD69 has the highly conserved amino acid sequences found in the C-type lectin family, suggesting that the conserved residues may be important for conformation and binding to the, as yet unidentified ligand. In addition, the cytoplasmic tail of bovine CD69 has two casein kinase-2 (CK-2) phosphorylation sites. These data suggest that bovine CD69 plays an important role in the activation of lymphocytes.

Scavenger receptor cysteine-rich domains 9 and 11 of WC1 are receptors for the WC1 counter receptor

Workshop cluster 1 (WC1) is a member of the scavenger receptor cysteine-rich (SRCR) superfamily that includes CD5, CD6, CD163, and M160. Bovine WC1 consists of 11 SRCR domains, a unique domain 1, and two homologous 5 SRCR domain cassettes, WC1 domains 2-6 and 7-11. The porcine orthologue of WC1 contains five SRCR domains with a different domain arrangement. Although the function of WC1 is unknown, WC1 is proposed to be an accessory or homing molecule. Thus, identification of cells that express the counter receptor for WC1 (WC1-CR) is critical to understanding the function of WC1. For this reason, we constructed WC1-human immunoglobulin G1 fusion proteins to identify the binding domain of WC1 and cells that express the WC1-CR. Immunohistochemical analysis revealed WC1 domains 9 and 11 bind cells with macrophage and dendritic cell morphology and cells in ellipsoids in the spleen. These results and the finding of conserved signaling motifs in the cytoplasmic tail suggest WC1 may be an accessory molecule.

Identity of activation molecule 3 on superantigen-stimulated bovine cells is CD26

Most CD8(+) T cells in cultures of bovine mononuclear cells stimulated with staphylococcal enterotoxin C1 develop an unusual phenotype characterized by expression of activation molecule 3 (ACT3). This superantigen-dependent phenotype may be relevant to immunopathogenesis mediated by certain microbial toxins. The size and N-terminal sequence of immunoprecipitated ACT3 indicate that ACT3 is the bovine orthologue of CD26.

The revised Sign and Symptom Check-List for HIV (SSC-HIVrev)

Symptom management for persons living with HIV/AIDS is recognized as an extremely important component of care management. This article reports on the continuing validation of the revised Sign and Symptom Check-List for Persons With HIV Disease (SSC-HIVrev). The initial validation study used a combined sample of 933 HIV-positive persons and concluded that the validity and reliability of the instrument were adequate to measure patients' self-report of HIV-related signs and symptoms. The revised scale includes items to measure gynecological-related symptoms and the impact of lipodystrophy (body fat redistribution) due to antiretroviral therapy on patients' symptom experience. The scale structure (factor analysis) and reliability estimates were recalculated in a new sample of 372 HIV-positive persons. Based on reviewing the clusters of items, factor loadings, reliability estimates, and clinical interpretability, an 11-factor solution was determined that explained 73.3% of the variance. Of the retained factors, 4 had eigenvalues less than 1, yet they explained significant amounts of variance in the rotated sums of squares loading (5.0%, 4.3%, 4.3%, and 3.6%, respectively), the reliability estimates were good, and the factors had clinical meaning. The revised scale (SSC-HIVrev) has three parts: Part 1 consists of 45 items that clustered into 11 factor scores along with a total score, with reliability estimates ranging from .76 to .91; Part 2 consists of 19 HIV-related symptoms that do not cluster into factor scores but may be of interest from a clinical perspective; and Part 3 consists of 8 items related to gynecological symptoms for women. These 8 items were submitted to a principal components factor analysis with varimax rotation (n = 118 HIV-positive women), and a 1-factor solution explained 71.8% of the variance, with a reliability estimate of .94. The psychometric properties of the SSC-HIVrev are presented.

The use of crossreactive monoclonal antibodies to characterize the immune system of the water buffalo (Bubalus bubalis)

One of the major difficulties in studying the mechanisms of host defense in economically important species indigenous to Asia and the Middle East is the lack of monoclonal antibody (mAb) reagents that define the immune systems of species other than cattle, goats, sheep, and pigs. One strategy that could obviate this problem at minimal cost is to identify existing mAbs that recognize conserved epitopes on orthologous major histocompatibility complex (MHC) and leukocyte differentiation molecules. To explore the potential of this approach, we screened a large set of mAbs that recognize bovine MHC class I and II molecules and leukocyte differentiation molecules to identify mAbs that react with orthologous molecules in water buffalo. One hundred thirty eight were found that recognize conserved determinants on orthologous molecules. In addition to identifying a useful set of reagents, the study has provided insight into the composition of the immune system of the water buffalo (Bubalus bubalis).

Synaptic plasticity in sympathetic ganglia from acquired and inherited forms of ouabain-dependent hypertension

Altered sympathetic nervous system activity has been implicated often in hypertension. We examined short-term potentiation [posttetanic potentiation (PTP)] and long-term potentiation (LTP) in the isolated superior cervical ganglia (SCG) from Sprague-Dawley (SD) rats given vehicle, digoxin, or ouabain by subcutaneous implants as well as in animals with ouabain-induced hypertension (OHR), and inbred Baltimore ouabain-resistant (BOR) and Baltimore ouabain-sensitive (BOS) strains of rats. Postganglionic compound action potentials (CAP) were used to determine PTP and LTP following a tetanic stimulus (20 Hz, 20 s). Baseline CAP magnitude was greater in ganglia from OHR than in vehicle-treated SD rats before tetanus, but the decay time constant of PTP was significantly decreased in OHR and in rats infused with digoxin that were normotensive. In hypertensive BOS and OHR, the time constants for the decay of both PTP and LTP (t(L)) were increased and correlated with blood pressure (slope = 0.15 min/mmHg, r = 0.52, P < 0.047 and 6.7 min/mmHg, r = 0.906, P < 0.0001, respectively). In BOS and OHR, t(L) (minutes) was 492 +/- 40 (n = 7) and 539 +/- 41 (n = 5), respectively, and differed (P < 0.05) from BOR (257 +/- 48, n = 4), SD vehicle rats (240 +/- 18, n = 4), and captopril-treated OHR (370 +/- 52, n = 5). After the tetanus, the CAP at 90 min in BOS and OHR SCG declined less rapidly vs. SD vehicle rats or BOR. Captopril normalized blood pressure and t(L) in OHR. We conclude that the duration of ganglionic LTP and blood pressure are tightly linked in ouabain-dependent hypertension. Our results favor the possibility that enhanced duration of LTP in sympathetic neurons contributes to the increase in sympathetic nerve activity in ouabain-dependent hypertension and suggest that a captopril-sensitive step mediates the link of ouabain with LTP.

Analysis of monoclonal antibodies reacting with molecules expressed on gammadelta T-cells

Twenty-six monoclonal antibodies (mAbs) selected after the first round of analysis in the Third International Swine Workshop were grouped with additional mAbs from the first and second workshops and mAbs under study for further evaluation. Preparations of peripheral blood leukocytes were used in single and multicolor flow cytometric (FC) analyses. Six mAbs did not react with gammadelta T-cells. Two were negative for all tested specificities. Seven mAbs recognized molecules expressed on gammadelta T-cells that were not lineage restricted. One of these from the first workshop (2B11) yielded a pattern of labeling identical to a mAb under study (PGB73A). Ten mAbs were characterized in previous workshops and known to react with the gammadelta TCR or molecules expressed on subsets of gammadelta T-cells. One belonged to SWC4, two to SWC5, and one to SWC6. Two mAbs from the second workshop recognized a molecule or molecules expressed on subsets of gammadelta T-cells. A new mAb (PPT16) added late to the workshop following a request by the workshop chairs appeared to recognize a determinant expressed on the gammadelta TCR/CD3 molecular complex.

Overview of the Third International Workshop on Swine Leukocyte Differentiation Antigens

The aim of the Third International Workshop on Swine Leukocyte Differentiation Antigens (CD workshop), supported by the Veterinary Immunology Committee (VIC) of the International Union of Immunological Societies (IUIS), was to standardize the assignment of monoclonal antibodies (mAb) reactive with porcine leukocyte differentiation antigens and to define new antibody clusters, using nomenclature in accordance with human and ruminant CD nomenclature, as agreed at the summary meeting of the Second International Swine CD Workshop in Davis, 1995: only mAb with proven reactivity for the orthologous porcine gene product or cross-reactivity for the human gene products, were given the full CD nomenclature, all other allocations were prefixed with "w". As in previous workshops, the overall organization was entrusted to the chair and first author, with support by the chair of the previous workshop and second author. In addition to the existing 26 pig leukocyte CD/SWC determinants established in previous workshops, this workshop established/confirmed another 11 CDs for pig leukocytes, identified by a total of 21 mAb: CD11R1 (2 mAb), CD11R2 (1 mAb), CD11R3 (4 mAb), wCD40 (1 mAb), wCD46 (4 mAb), wCD47 (3 mAb), wCD49d (1 mAb), CD61 (1 mAb), wCD92 (1 mAb), wCD93 (1 mAb) and CD163 (2 mAb).

Tissue distribution of CD6 and CD6 ligand in cattle: expression of the CD6 ligand (CD166) in the autonomic nervous system of cattle and the human

We studied the tissue distribution of CD6(+) lymphocytes and cells expressing the CD6 ligand (also known as activated leukocyte cell adhesion molecule CD166) in calves by immunohistochemistry using an anti-bovine CD6 monoclonal antibody (mAb), a human CD6 (huCD6)-immunoglobulin G1 fusion protein (huCD6-Ig), and an anti-human CD166 (anti-huCD166) mAb. The huCD6-Ig and anti-huCD166 mAb bound to the sympathetic and parasympathetic nerve fibers but not to myelinated nerve fibers in the spinal nerve. Studies with human tissue using the anti-huCD166 mAb yielded identical patterns of labeling. Dense accumulations of CD6(+) lymphocytes were present in areas of the thymuses and spleens of calves, in areas innervated by huCD6-Ig(+) nerves. The cDNAs encoding the bovine CD166 and CD6 were isolated from the sympathetic ganglion and spleen, respectively. Predicted amino acid residues that are important for human and mouse CD6-CD166 binding were also conserved in bovine CD6 and CD166. Bovine CD166 transcripts were detected by reverse transcriptase-PCR in all the tissues that bound huCD6-Ig. These results show that the bovine orthologue of CD166 was constitutively expressed in the autonomic nervous systems of cattle and suggest that CD6(+) lymphocytes adhere to CD166(+) autonomic nerve terminals via CD6.

Flow cytometric analysis of an immunodeficiency disorder affecting juvenile llamas

The present study was undertaken to characterize the immune system of llamas and alpacas and establish the basis for an immunodeficiency disorder affecting juvenile llamas. Flow cytometric (FC) analysis of the immune system with a panel of monoclonal antibodies (mAbs) revealed the immune system of llamas and alpacas is similar in leukocyte subset composition to that in ruminants. Peripheral blood mononuclear cells in adults are comprised of surface immunoglobulin (sIg(+)) B-cells (31%+/-8 S.D.), alphabeta T-cells (27%+/-12 S.D.), WC1(+) gammadelta T-cells (16%+/-11 S.D.), and 5-16% monocytes. In contrast to cattle, goats, and sheep, however, the frequency of WC1(+) gammadelta T-cells is not high in juveniles but similar to the frequency in adults. Also, sIg(+) B-cells are present in high concentration in juveniles (43%+/-11 S.D. ). Expression of major histocompatibility class II molecules on resting T-cells was low or absent. Comparative analysis of peripheral blood lymphocyte composition in normal juvenile llamas and llamas presenting with the signs of the juvenile llama immunodeficiency syndrome (JLIDS) revealed the concentration of B-cells is extremely low (1-5%) in affected animals. The findings suggest JLIDS is attributable to an autosomal recessive genetic defect in the development of B-cells.

Induction of type 2 cytokines by a staphylococcal enterotoxin superantigen

Persistent intramammary infections of dairy cows with Staphylococcus aureus may involve immunosuppression mediated by bacterial toxins such as enterotoxins and other super-antigens (SAgs). Previously we found that stimulation of bovine PBMC with staphylococcal enterotoxin C (SEC) induced a unique phenotype of activated CD8+ T cells expressing a newly identified activation molecule, ACT3. In the present study we found that SEC induced the expression of interleukin (IL)-4 and IL-10 mRNAs, two cytokines associated with type 2 responses. Elevated levels of IL-4 and IL-10, observed between day 0 and day 4 of culture, were associated with temporary inhibition of proliferative responses of T cells, evidenced by a decrease in numbers of CD4+ T cells and a small increase in numbers of CD8+ T cells. Vigorous proliferation of T cells occurred between days 4 and 7 of culture and with a bias towards CD8+ T cells. Acquisition of the ACT3+ phenotype by CD8+ T cells was preceded by induction of IL-4 mRNA. Thus, in the bovine system, SAgs may hinder protective responses by inducing type 2 cytokines, which interfere with immune clearance of many microbial pathogens. The results of the study are consistent with the hypothesis that SAgs are involved in immunosuppression, and suggest possible immunomodulatory mechanisms.

Observations on the nature, biosynthesis, secretion and significance of endogenous ouabain

The human circulation contains four readily distinguishable biologically active inhibitors of the sodium pump that appear to be endogenous to mammals. Of these, one has been purified to homogeneity and by numerous chromatographic, mass spectral, biochemical, and physiological analyses has been shown to be a novel steroidal isomer of ouabain in which the location and orientation of two or more steroidal hydroxyl groups differ. The human endogenous "ouabain" (EO) is a high affinity reversible inhibitor of the pump with inotropic and vasopressor activity. Circulating levels of EO depend upon the adrenal cortex and metabolic events preceding and following pregnenolone formation are involved in EO biosynthesis. Within the adrenal gland, the stimulus-secretion mechanisms for EO secretion are distinct from those for aldosterone highlighting different regulation. Among Caucasians with essential hypertension, 30-45% have elevated circulating levels of EO. Sustained elevation of plasma ouabain in rats induces chronic hypertension with characteristics similar to those in patients and whose severity is determined by inherited factors and renal function. In conclusion, at least one of the mammalian counterparts to the cardiac glycosides is a novel steroidal isomer of ouabain. The isomer is secreted by the adrenal cortex, and augments cardiovascular function. The observation of this entity in the human circulation, the demonstration of its biosynthesis, and the existence of specific receptors suggest to us that EO is a novel adrenocortical hormone and may be part of a broader family of novel mammalian steroids that regulate the sodium pump and other processes.

Comparison of the unique characteristics of the immune system in different species of mammals

The current interpretation of how cytokines regulate immune responses is based largely on studies conducted in humans and rodents. As summarized here, comparative studies have revealed significant differences in the composition of the immune system in other species. The difference noted emphasize that it will not be possible to fully understand the role of cytokines in immune regulation without comparative studies that include analysis of cytokine function in additional species.

Report of the Second Equine Leucocyte Antigen Workshop, Squaw valley, California, July 1995

The final assignment of antibody clusters for leucocyte antigens and immunoglobulins, as described in detail in Sections 3 and 4, is summarized in Table 4. Together with other mAbs developed outside of ELAW II (Table 9) this pool of reagents represent a powerful array of tools for the study of equine immunity. The Second Equine Leucocyte Antigen Workshop made considerable advances in pursuing the objectives of establishing the specificities of mAbs and achieving consensus on the nomenclature for equine leucocyte and immunoglobulin molecules. Of equal importance, several productive collaborations were fostered among the participating laboratories and observers. Overall, enormous advances have been made in the past decade since mAbs specific for equine leucocyte antigens and immunoglobulins were first reported. There remains enormous scope and need for further studies of equine leucocyte antigens and immunoglobulins, both for the purposes of comparative immunology and for the good of the horse. In the future novel techniques will be required to develop reagents for specific target antigens such as the orthologues of the CD25 or CD45 isoforms. In studies of equine immunoglobulins the functional role of the IgG isotypes must be better established, reagents for IgE must be developed, and cloning of the immunoglobulin heavy chain genes will be essential if the complexities of the IgG sub-isotypes are to be elucidated. The tasks still facing the currently small group of equine immunologists throughout the world remain formidable, and will only be tackled successfully in a spirit of collaboration.

Characterisation of a monoclonal antibody recognising the CD3epsilon chain of the bovine T cell receptor complex

We describe the characterisation of a monoclonal antibody (mAb), designated MM1A, which reacts with an antigen molecule on the surface of bovine alphabeta and gammadeltaTcR+ T cells. The mAb immunoprecipitated a series of polypeptides of 21 kDa, 22 kDa, 32 kDa, 36 kDa and 44 kDa which is consistent with it recognising the TcR/CD3 complex. COS cells, transfected with a cDNA encoding the bovine CD3epsilon chain, reacted with mAb MM1A indicating that the epitope recognised is on the epsilon chain of the complex and confirming that the mAb recognised bovine CD3.

Activation of bovine lymphocyte subpopulations by staphylococcal enterotoxin C

Staphylococcus aureus is a major mastitis-causing pathogen in cattle. The chronic nature of bovine staphylococcal mastitis suggests that some products or components of S. aureus may interfere with the development of protective immunity. One class of molecules that could be involved are superantigens (SAgs). Although a significant number of mastitis isolates produce SAgs, the effect of these molecules on the bovine immune system is unresolved. To determine if immunosuppression caused by SAgs could play a role in pathogenesis, we monitored bovine lymphocytes exposed to staphylococcal enterotoxin C1 (SEC1). Activation of bovine lymphocytes by either SEC1 or concanavalin A (ConA) was influenced by the gammadelta/alphabeta T-cell ratio in the culture. Compared to ConA-induced stimulation, cultures stimulated with SEC1 generated small numbers of CD4+ alphabeta T cells expressing high levels of interleukin-2 receptor alpha chain (IL-2R alpha) and major histocompatibility complex class II (MHCII), suggesting that SAg exposure does not lead to full activation of these cells. This state of partial activation was most pronounced in cultures with a high gammadelta/alphabeta ratio. In contrast, significant numbers of CD8+ alphabeta T cells expressed high levels of IL-2R alpha and MHCII, regardless of the gammadelta/alphabeta ratio and the stimulant used. CD8+ blasts in cultures stimulated with SEC1 also expressed another activation marker, ACT3, previously detected predominantly on thymocytes and CD4+ T cells. Although gammadelta CD2- and CD2+ T cells expressed MHCII and IL-2R alpha following stimulation with SEC1, only a few cells increased to blast size, suggesting that they were only partially activated. The results suggest ways in which SAgs might facilitate immunosuppression that promotes the persistence of bacteria in cattle and contributes to chronic intramammary infection.

Analysis of monoclonal antibodies that recognize gamma delta T/null cells

Thirty two monoclonal antibodies (mAbs) from the first round of analysis in the Second International Swine CD Workshop were placed together with additional mAb derived from the first workshop in the null cell panel for further evaluation. Preparations of peripheral blood leukocytes, concanavalin A stimulated peripheral blood mononuclear cells, and spleen cells were used in flow cytometric analyses. Nineteen mAbs identified molecules that were not expressed on null cells, not lineage specific, or recognized activation molecules. Sixteen mAbs including control mAbs were identified that were specific for null cells. One of the latter mAbs, 041 (PGBL22A), that recognizes a determinant on a constant region of porcine gamma delta TcR established the majority of null cells are gamma delta T cells. Use of this mAb in further comparisons demonstrated the gamma delta T cell population is comprised of two major subpopulations, one negative and one positive for CD2. Two color analyses demonstrated that 11 of the mAbs formed a broad cluster that included control mAbs 188 (MAC320) that defined the CD2 negative SWC6 cluster in the first workshop and mAb 122 (CC101) that might recognize an orthologue of bovine WC1 and nine mAbs that recognize determinants on one or more molecules with overlapping patterns of expression on subsets of CD2- gamma delta T cells. Two groups of mAbs formed the previously identified subset clusters SWC4 and SWC5. Two new mAbs formed a third subcluster. Three mAbs did not form clusters. Three mAbs predicted to recognize TcR in the first workshop (020 [PT14A], 021 [PT79A], and 022 [MUC127A]) and mAb PGBL22A were shown to immunoprecipitate a 37, 40 kDa heterodimer.

DNA synapomorphies for a variety of taxonomic levels from a cosmid library from the New World bat Macrotus waterhousii

An effective method yielding taxon-specific markers from the genome of a single individual would be valuable for many types of scientific investigations, including systematic, forensic, conservation, and evolutionary studies. We explored the use of cosmid libraries, with insert sizes averaging 35 kb, to streamline the process of locating sequences of DNA that can serve as taxonomic markers from the specific to the ordinal levels. By screening approximately 2.6% of the leaf-nosed bat (Macrotus waterhousii) genome, we identified several potential DNA fragments that appear to be synapomorphic for a variety of taxonomic levels. A more thorough analysis of the markers documented that 17 Macrotus-specific clones represent three distinct DNA generic markers, whereas 30 microchiropteran clones represent multiple copies of a single family of repetitive DNA. The Microchiroptera taxon markers hybridize with representatives of most of the Microchiroptera families; however, no hybridization was detected for members of the superfamily Rhinolophoidea. These results demonstrate that cosmid libraries can be a valuable source for isolating taxon-specific markers from mammals even when the insert size is as large as 35 kb.

Early Speech Changes in Children with Multichannel Cochlear Implants

A number of studies have demonstrated that cochlear implants provide an improved auditory signal and enhance the development of speech-perception and production skills for profoundly deaf children. However, exactly when these early speech skills begin to develop remains unclear. To explore this issue, we observed, for a 1-year period, four prelingually deaf children who underwent implantation consecutively within 1 month of each other, and we paid particular attention to the first few months of rehabilitation. We found immediate speech scores as early as the first day of implant tune-up. Speech production continued to improve rapidly throughout the first 4 months but exhibited a generally slower rate of progress in some of the speech-production skills at 1 year. We also found vowel-production skills to be the easiest to achieve, with word-pattern recognition and consonant voicing of intermediate difficulty. Consonant placing and manner of consonant production were the hardest skills to achieve. Results of speech-perception tests 1 year after implantation were markedly improved over preimplantation levels in three of the four children. These early speech changes stress the need for maximization of the capability of the cochlear implant by institution of immediate and intensive speech rehabilitation efforts for prelingually deaf children.

Early speech changes in children with multichannel cochlear implants

A number of studies have demonstrated that cochlear implants provide an improved auditory signal and enhance the development of speech-perception and production skills for profoundly deaf children. However, exactly when these early speech skills begin to develop remains unclear. To explore this issue, we observed, for a 1-year period, four prelingually deaf children who underwent implantation consecutively within 1 month of each other, and we paid particular attention to the first few months of rehabilitation. We found immediate speech scores as early as the first day of implant tune-up. Speech production continued to improve rapidly throughout the first 4 months but exhibited a generally slower rate of progress in some of the speech-production skills at 1 year. We also found vowel-production skills to be the easiest to achieve, with word-pattern recognition and consonant voicing of intermediate difficulty. Consonant placing and manner of consonant production were the hardest skills to achieve. Results of speech-perception tests 1 year after implantation were markedly improved over preimplantation levels in three of the four children. These early speech changes stress the need for maximization of the capability of the cochlear implant by institution of immediate and intensive speech rehabilitation efforts for prelingually deaf children.

Analysis of monoclonal antibodies specific for the gamma delta TcR

gamma delta T cells in ruminants can be subdivided in two or more subpopulations on the basis of the expression of surface antigen WC1, which can exist in different isoforms. In this study, 18 monoclonal antibodies (mAbs) submitted to the Third International Workshop that were predicted to react with gamma delta TcR molecules were analysed and expression of their antigens was investigated on the different gamma delta T cell subpopulations. A set of control mAbs positive for TcR1 (86D), BoCD3 (MM1A), WC1 (B7A1, BAQ4A, CACTB32A, and BAQ89A) was included for comparative studies. Previous investigations demonstrated eight of the mAbs immunoprecipitated peptides with apparent M(r)s of 37 and/or 47 kDa, indicating they recognized determinants on the T cell receptor, TcR1. Two color flow cytometric analyses in the present study demonstrated the mAbs formed three groups; group 1, a set of mAbs that recognize TcR1 determinants expressed on all gamma delta T cells and groups 2 and 3, sets of mAbs that recognize TcR1 determinants on some gamma delta T cells: TcR1-N6 and TcR1-N7 respectively. mAbs from the latter groups define families of TcR1 molecules that express either one or both of the determinants. These antigenically distinct forms of TcR1 are expressed in equal proportion on the two gamma delta T cell populations that express one of the mutually exclusive isoforms of WC1, WC1-N3 and WC1-N4. The data indicate usage of the mAb-defined families of the gamma delta TcR is primarily restricted to the WC1+ subpopulation of gamma delta T cells. However, a small subpopulation of CD2+, WC1- gamma delta T cells expresses a form of TcR1 positive for the determinant TcR1-N6.