What supports and services post COVID-19 do children with disabilities and their parents need and want, now and into the future?

Introduction

Children and youth with disabilities and special healthcare needs, and their families, have been uniquely affected by the COVID-19 pandemic. However, the voices of children themselves are still not well represented in the existing literature.

Methods

This qualitative descriptive study used a combination of visual methods and interviews to learn about the experiences of Canadian children with disabilities (n=18) and their parents (n=14) during the COVID pandemic and into the post-pandemic period. Data collection was carried out between January and July 2023. The aim was to identify the supports and services children and families need at present and moving forward.

Results

Families' pandemic experiences were complex and nuanced. For many, the pandemic complicated and disrupted everyday activities and supports. These disruptions were largely buffered by parents. However, some families also identified unexpected benefits. Key themes pertaining to present and future needs included the need for services that are flexible; consistent; conducive to relationship-building; comprehensive; coordinated across sectors; and designed to support the needs of the whole family.

Discussion

Implications for policy and practice are outlined.

Protein Therapeutic Target Candidates Against Acinetobacter baumannii, a Pathogen of Concern to Planetary Health: A Network-Based Integrative Omics Drug Discovery Approach

Acinetobacter baumannii, an opportunistic gram-negative pathogen responsible for several nosocomial infections, has developed resistance to various antibiotics. Proteins involved in the two-component system (TCS), virulence, and antibiotic resistance (AR), help this pathogen in regulating antibiotic susceptibility and virulence mechanisms. The present study reports a network-based integrative omics approach to drug discovery to identify key regulatory proteins as therapeutic candidates against A. baumannii. We collected data on the TCS, virulence, and AR proteins from various databases (P2CS, VFDB, ARDB, and PAIDB), which were subjected to network, host-pathogen, and gene expression data analysis. Network analysis identified 43 hubs, and 10 proteins were found to be interacting with human proteins associated with vital pathways. Of the 53 (43 + 10) pathogen proteins, 46 had no orthologs in the human host. Twelve proteins, namely, RpfC, Wzc, OmpR, EnvZ, BfmS, PilG, histidine kinase, ABC 3 transport family protein, outer membrane porin OprD family, CsuD, Pgm, and LpxA, were differentially expressed in the resistant strain. We propose these proteins as key regulators that warrant evaluation as therapeutic target candidates in the future. Furthermore, structure prediction of ABC 3 transport family protein was performed as a case study. The findings from this study are poised to facilitate and inform drug discovery and development against A. baumannii.

The phytochemical brazilin suppress DNMT1 expression by recruiting p53 to its promoter resulting in the epigenetic restoration of p21 in MCF7cells

BACKGROUND

Cancer is an outcome of uncontrolled cell division eventually associated with dysregulated epigenetic mechanisms, including DNA methylation. DNA methyltransferase 1 is ubiquitously expressed in the proliferating cells and is essential for the maintenance of DNA methylation. It causes the abnormal silencing of tumor suppressor genes in human cancer which is necessary for proliferation, cell cycle progression, and survival. DNMT1 is involved in tumorigenesis of several cancers, its upregulation potentially upscale the promoter level inactivation of transcription of a tumor inhibitory gene by introducing repressive methylation marks on the CpG islands. This epigenetic perturbation caused by DNMT is targeted for cancer therapeutics.

PURPOSE

To demonstrate the proliferative inhibitory potential of brazilin in human breast cancer cell line (MCF-7) with concurrent mitigation of DNMT1 functional expression and to understand its effect on downstream targets like cell cycle inhibitor p21.

STUDY DESIGN/ METHODS

The impact of brazilin on the growth and proliferation of the MCF-7 cells was determined using the XTT assay. The global DNA 5-methyl cytosine methylation pattern was analyzed upon brazilin treatment. The gene and protein expression of DNMTs were determined with quantitative RTPCR and western blots respectively. The potential binding sites of transcription factors in the human DNMT1 promoter were predicted using the MatInspector tool on the Genomatix software. The chromatin immunoprecipitation (ChIP) assay was performed to demonstrate the transcription factors occupancy at the promoter. Methylation of promoter CpG islands was determined by the methylation-specific PCR (MSP) upon brazilin treatment. The molecular docking of the human DNMT1 with brazilin (ligand) was performed using the Schrödinger suite.

RESULTS

The heterotetracyclic compound brazilin, present in the wood of Caesalpinia sappan, inhibited the proliferation of the human breast cancer cell line (MCF-7) and reduced the DNMT1 expression with a decrease in global DNA methylation. Brazilin, by activating p38 MAPK and elevating p53 levels within the exposed cells. The elevated level of p53 enriched the occupancy at binding sites within 200 bp upstream to the transcription start site in the DNMT1 promoter, resulting in reduced DNMT1 gene expression. Furthermore, the brazilin restored the p21 levels in the exposed cells as the CpGs in the p21 promoter (-128 bp/+17 bp) were significantly demethylated as observed in the methylation-specific PCR (MSP).

CONCLUSION

Highly potential anti-proliferative molecule brazilin can modulate the DNMT1 functional expression and restore the cell cycle inhibitor p21expression. We propose that brazilin can be used in therapeutic interventions to restore the deregulated epigenetic mechanisms in cancer.

A Comparative Genomics Approach for Shortlisting Broad-Spectrum Drug Targets in Nontuberculous Mycobacteria

Many members of nontuberculous mycobacteria (NTM) are opportunistic pathogens causing several infections in animals. The incidence of NTM infections and emergence of drug-resistant NTM strains are rising worldwide, emphasizing the need to develop novel anti-NTM drugs. The present study is aimed to identify broad-spectrum drug targets in NTM using a comparative genomics approach. The study identified 537 core proteins in NTM of which 45 were pathogen specific and essential for the survival of pathogens. Furthermore, druggability analysis indicated that 15 were druggable among those 45 proteins. These 15 proteins, which were core proteins, pathogen-specific, essential, and druggable, were considered as potential broad-spectrum candidates. Based on their locations in cytoplasm and membrane, targets were classified as drug and vaccine targets. The identified 15 targets were different enzymes, carrier proteins, transcriptional regulator, two-component system protein, ribosomal, and binding proteins. The identified targets could further be utilized by researchers to design inhibitors for the discovery of antimicrobial agents.

Incidence, timing, presentation, treatment, and outcomes of second primary head and neck squamous cell carcinoma after oral cancer

After their initial presentation of oral squamous cell carcinoma (SCC), patients have a lifelong risk of developing another new SCC of the head and neck. The aim of this study was to establish second primary rates, baseline characteristics (site, clinical or pathological stage, and smoking and alcohol history), timing, presentation, treatment, and outcomes. From the regional unit we analysed records of patients treated with curative intent for their first oral cancer between 2002 and 2007 inclusive. All patients had had at least 10 years of follow up either to death or the end of 2017. A total of 347 patients had been treated with curative intent, and of them, 29 had a second primary at a median (IQR) of 52 (30-79) months after the index operation. The incidence of developing a second primary tumour within two years was 1.7% (95% CI: 0.7% to 3.7%), within five years was 4.9% (95% CI: 2.9% to 7.7%), and within 10 years was 7.8% (95% CI: 5.1% to 11.1%). Early stage of first cancer was the only significant factor (p=0.001) for development of a second primary within 10 years, reflecting survivorship. Most second primaries (21 patients) were staged as early, and by visual inspection. Most (n=20) were within the oral cavity, one of which overlapped the oropharynx; eight others were in the oropharynx, and one in the larynx. Most patients (n=22) were treated by operation with curative intent. Three were treated palliatively. Patients need to be aware of the risk of a second primary and, as most are in the mouth or oropharynx, there is a role for surveillance by primary dental care practitioners.

CHD1 loss sensitizes prostate cancer to DNA damaging therapy by promoting error-prone double-strand break repair

Background

Deletion of the chromatin remodeler chromodomain helicase DNA-binding protein 1 (CHD1) is a common genomic alteration found in human prostate cancers (PCas). CHD1 loss represents a distinct PCa subtype characterized by SPOP mutation and higher genomic instability. However, the role of CHD1 in PCa development in vivo and its clinical utility remain unclear.

Patients and methods

To study the role of CHD1 in PCa development and its loss in clinical management, we generated a genetically engineered mouse model with prostate-specific deletion of murine Chd1 as well as isogenic CHD1 wild-type and homozygous deleted human benign and PCa lines. We also developed patient-derived organoid cultures and screened patients with metastatic PCa for CHD1 loss.

Results

We demonstrate that CHD1 loss sensitizes cells to DNA damage and causes a synthetic lethal response to DNA damaging therapy in vitro, in vivo, ex vivo, in patient-derived organoid cultures and in a patient with metastatic PCa. Mechanistically, CHD1 regulates 53BP1 stability and CHD1 loss leads to decreased error-free homologous recombination (HR) repair, which is compensated by increased error-prone non-homologous end joining (NHEJ) repair for DNA double-strand break (DSB) repair.

Conclusions

Our study provides the first in vivo and in patient evidence supporting the role of CHD1 in DSB repair and in response to DNA damaging therapy. We uncover mechanistic insights that CHD1 modulates the choice between HR and NHEJ DSB repair and suggest that CHD1 loss may contribute to the genomic instability seen in this subset of PCas.

Knowledge, attitudes, beliefs, and behaviors of university students, faculty, and staff during a meningococcal serogroup B outbreak vaccination program

OBJECTIVES

During an outbreak of invasive meningococcal B disease on a university campus, we explored the knowledge, attitudes, beliefs, and behaviors of members of the university community in relation to the disease, the vaccine, and the vaccination program.

DESIGN

All students, faculty and staff were invited by email to participate in a 71-item online survey, which was administered after completion of the mass clinics for the first and second doses of a meningococcal B vaccination program.

RESULTS

A total of 404 individuals responded to the survey; 75.7% were students. Knowledge about meningococcal disease and vaccine was generally high; more than 70% correct responses were received on each knowledge question except for one question about the different meningococcal serogroups. Gender (female) and higher knowledge scores were significantly associated with either being immunized or intending to be immunized (p<0.05). Positive attitudes about immunization, concern about meningococccal infection, a sense of community responsibility, and trust in public health advice also correlated with being vaccinated or intending to be vaccinated (p<0.05).

CONCLUSIONS

A successful mass vaccination program in a Nova Scotia university was associated with high levels of knowledge, positive attitudes toward vaccination, and positive attitudes toward public health recommendations.

Rapid surveillance for health events following a mass meningococcal B vaccine program in a university setting: A Canadian Immunization Research Network study

An outbreak of Neisseria meningitidis serotype B infection occurred at a small residential university; public health announced an organizational vaccination program with the 4-component Meningococcal B (4CMenB) vaccine (Bexsero(TM), Novartis/GlaxoSmithKline Inc.) several days later. Since there were limited published data on reactogenicity of 4CMenB in persons over 17years of age, this study sought to conduct rapid surveillance of health events in vaccinees and controls using an online survey. Vaccine uptake was 84.7% for dose 1 (2967/3500) and 70% (2456/3500) for dose 2; the survey response rates were 33.0% (987/2967) and 18.7% (459/2456) in dose 1 and dose 1 recipients respectively, and 12% in unvaccinated individuals (63/533). Most students were 20-29years of age (vaccinees, 64.0%; controls, 74.0). A new health problem or worsening of an existing health problem was reported by 30.0% and 30.3% of vaccine recipients after doses 1 and 2 respectively; and by 15.9% of controls. These health problems interfered with the ability to perform normal activities in most vaccinees reporting these events (74.7% post dose 1; 62.6% post dose 2), and in 60% of controls. The health problems led to a health care provider visit (including emergency room) in 12.8% and 14.4% of vaccinees post doses 1 and 2, respectively and in 40% of controls. The most common reactions in vaccinees were injection site reactions (20.6% post dose 1, 16.1% post dose 20 and non-specific systemic complaints (22.6% post dose 1, 17.6% post dose 2). No hospitalizations were reported. An online surveillance program during an emergency meningococcal B vaccine program was successfully implemented, and detected higher rates of health events in vaccinees compared to controls, and high rates of both vaccinees and controls seeking medical attention. The types of adverse events reported by young adult vaccinees were consistent with those previously.

Unequivocal evidence of enhanced magnetodielectric coupling in Gd3+substituted multiferroic Bi2Fe4O9

We report an enhanced magnetodielectric (MD) coupling in antiferromagnetic Bi₂Fe₄O₉(BFO) lightly substituted by gadolinium (Gd³⁺).

Liquid-phase denaturant gradient gel electrophoresis profiles of rumen bacteria from Brahman cross steers selected into two groups on the basis of post-weaning liveweight gain on low crude protein pasture

Two experiments were conducted to evaluate the relationship between rumen liquid-associated bacterial community structures and post-weaning liveweight gain (LWG) of Brahman crossbred steers. Bacterial diversity was assessed using denaturant gradient gel electrophoresis (DGGE). In Experiment 1, 16 steers were selected from a group of 100 steers by pairing steers with the same weaning weight, but different LWG 90 days after weaning (n = 8 highest growth, 0.21 ± 0.01 kg/day; and n = 8 lowest growth –0.07 ± 0.01 kg/day). Thereafter, steers were allocated to a 28-day pen study and fed Mitchell grass (Astrebla spp.) hay to examine DM intake and digestibility, rumen parameters and rumen microbial community in these two groups. Rumen fluid samples were taken by stomach tube 3 h after feeding on the last day of the pen phase. In Experiment 2, 12 pairs of weaned steers were selected from a group of 203 steers on the same basis as Experiment 1. The post-weaning LWG were 0.20 ± 0.03 and 0.02 ± 0.03 kg/day for the 12 highest and 12 lowest growth animals selected, respectively. Steers then grazed dry season Sabi grass (Urochloa mosambicensis) dominant pasture for 21 days, before rumen sampling 3 h after morning grazing by stomach tubing on the last day. In Experiment 1, there were no significant differences between the two groups in DM intake, digestibility, ruminal pH, total volatile fatty acid (VFA) concentration or the VFA proportion. In Experiments 1 and 2, rumen ammonia-N concentration was similar between LWG groups and there was no evidence of a relationship between liquid-phase DGGE profiles of rumen bacteria and high or low post-weaning LWG using multivariate analyses. Furthermore, the number of detected DGGE bands, the Shannon–Wiener and evenness indexes were not different between LWG groups. This DGGE analysis of the most abundant groups of rumen fluid-associated bacteria suggests that microbial populations were not related with the differences observed in post-weaning LWG within a group of weaners fed low crude protein diets.

COMORBIDITY IN A CLINICAL SAMPLE OF SUBSTANCE ABUSERS

The sample consisted of 125 male inpatients admitted to one of two substance abuse treatment centers in Iowa. They were diagnosed by means of the Diagnostic Interview Schedule Screening Interview-Quick-DIS version, the Structural Interview for DSM-III-R Personality Disorder (PD), revised, and the Substance Abuse Reporting System. The most frequently diagnosed comorbid Axis I conditions were anxiety and mood disorders, while the most frequently observed Axis II disorders were in Cluster B, borderline PD, and antisocial PD followed by Cluster C, avoidant PD, passive-aggressive PD and obsessive-compulsive PD; and then Cluster A; schizoid PD. Subjects diagnosed with Borderline PD showed the highest rate of comorbid psychopathology, including Axis I disorders of generalized anxiety disorder, major depression, cocaine dependence, and inhalant dependence. The most likely comorbid diagnosis for antisocial PD subjects was bipolar disorder. The schizoid PD and the NoPD groups were less likely to meet criteria for other Axis I disorders. A high rate of comorbid Axis II pathology was also found. Polysubstance dependent subjects were more likely to be diagnosed with anxiety disorder or bipolar disorder than were those who were not polysubstance dependent or were dependent only on alcohol. Polysubstance dependent men were at highest risk for Axis II disorders: 56% of them met criteria for a Cluster B PD, with borderline PD and histrionic PD most frequent.

Supplementation With Goldenseal (Hydrastis canadensis), but not Kava Kava (Piper methysticum), Inhibits Human CYP3A Activity In Vivo

The effects of goldenseal (Hydrastis canadensis) and kava kava (Piper methysticum) supplementation on human CYP3A activity were evaluated using midazolam (MDZ) as a phenotypic probe. Sixteen healthy volunteers were randomly assigned to receive either goldenseal or kava kava for 14 days. Each supplementation phase was followed by a 30-day washout period. MDZ (8 mg, per os) was administered before and after each phase, and pharmacokinetic parameters were determined using standard non-compartmental methods. Comparisons of pre- and post-supplementation MDZ pharmacokinetic parameters revealed significant inhibition of CYP3A by goldenseal (AUC(0-infinity), 107.9+/-43.3 vs 175.3+/-74.8 ng x h/ml; Cl/F/kg, 1.26+/-0.59 vs 0.81+/-0.45 l/h/kg; T(1/2), 2.01+/-0.42 vs 3.15+/-1.12 h; Cmax, 50.6+/-26.9 vs 71.2+/-50.5 ng/ml). MDZ disposition was not affected by kava kava supplementation. These findings suggest that significant herb-drug interactions may result from the concomitant ingestion of goldenseal and CYP3A substrates.

Physical status of newborns and neonatal outcome

OBJECTIVE

To determine the extent to which physical status at birth is associated with neonatal mortality and the causes of mortality vis-a-vis size at birth and gestational age.

METHOD

11,223 consecutive live births completing 26 weeks of gestation and weighing > or = 500 gm were included in the study. Birth weight and chest circumference were recorded as per WHO guidelines. Gestational age was calculated on the basis of L.M.P. and the new Ballard's score. Deaths occurring in the hospital within 28 days were recorded. Percentile values of gestational age specific birth weights were calculated separately for singletons and multiple births. Percentage of SGA was calculated with reference to WHO recommended values. Birth weight-gestational age-specific mortality rates were calculated at 2 wk and 500 gm intervals.

RESULT

Low-birth-weight babies constituted 39.8% of the total, much in excess of WHO recommended figure of 15%. 76% deaths occurred among LBW babies and 56.2% among preterms. Mortality showed remarkable decline as the birth weight increased to 2,000 gm. The lowest mortality was among singletons weighing 2,500-3,000 gm and of 38-40 weeks gestation. Prevalence of SGA at 40 and 42 weeks were 73.7% and 83.6% respectively. But, if SGA babies not categorised as LBW were excluded, the values came down to 32% and 36% respectively. 36% of all deaths occurred during the first 24 hrs of birth; asphyxia and related causes contributing to 50% of it.

CONCLUSION

Cut-off value of 2,000 gm instead of 2,500 gm for birth weight may be preferable in countries where most LBW babies are SGAs. Simultaneously, deaths in non-LBW babies due to perinatal causes contribute sgnificantly to total neonatal mortality and need due attention through sensitising obstetricians in essential newbom care and timely Intervention.

Cross-cultural comparison of clinical samples of Norwegian and Iowan women with substance-related disorders

The purpose of this study was to compare two clinical samples of women substance abusers, one from Iowa and one from Norway, along several dimensions: "substance abuse" history, current "abuse" pattern, parental and spouse drinking history, symptoms of psychological distress, and "vulnerability" to relapse. A higher percentage of women substance abusers from Iowa were divorced and lived alone, were "vulnerable" to relapse, and reported more life problems secondary to their substance use than women from Norway. The Iowa women had used more substances in addition to alcohol than had the Norwegian women. The Norwegian women reported greater intensity of emotional distress than the women from Iowa.

Another cause for bilateral haemorrhagic otorrhoea following trauma

Bleeding from the external auditory meatus (haemorrhagic otorrhoea) following head trauma is usually attributed to a basal skull fracture. However, it may also result from unsuspected facial trauma. We describe a case that highlights an usual but important differential diagnosis for bilateral haemorrhagic otorrhoea.

Repeated acetaminophen dosing in rats: adaptation of hepatic antioxidant system

Repeated dosing of acetaminophen (paracetamol) to rats is reported to decrease their sensitivity to its hepatotoxic effects, which are associated with oxidative stress and glutathione depletion. We determined if repeated acetaminophen dosing produced adaptive response of key antioxidant system enzymes. Male rats (Sprague-Dawley, 10 weeks) were given 800, 1200, or 1600 mg/kg/day acetaminophen by oral gavage for 4 days. Liver was assayed for oxidative stress and antioxidant markers: malondialdehyde (MDA), thiobarbituric acid reactive substance (TBARS), total antioxidant status (TAS), glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PD), catalase (CAT), and superoxide dismutase (SOD), and alanine transaminase (ALT) as a marker of hepatocellular injury. Acetaminophen at 1200/1600 mg/kg decreased GSH 26/47%, GPx 21/26%, CAT 35/28%, SOD 21/12%; and TAS 28/18% (correlated with CAT, r=0.91; SOD, r=0.66; GPx, r=0.45). Despite antioxidant deficiencies, and no TBARS change, MDA decreased 26%/33%/37% at 800/1200/1600 mg/kg, which correlated with increased GR (61%/62%/76%, r=0.77) and G6PD (130%/110%/190%, r=0.78). Both MDA (r=0.68) and G6PD (r=0.71) correlated with hepatic ALT, which decreased 27%/43%/48%, respectively. Resistance to acetaminophen hepatotoxicity produced by repeated exposure is partially attributable to upregulation of hepatic G6PD and GR activity as an adaptive and protective response to oxidative stress and glutathione depletion.

Dax1 antagonizes Sry action in mammalian sex determination

DAX1, which encodes an unusual member of the nuclear hormone-receptor superfamily, is a gene that may be responsible for a sex-reversal syndrome in humans, referred to as dosage-sensitive sex reversal, in which XY individuals carrying duplications of Xp21, part of the small arm of the X chromosome, develop as females. XY mice carrying extra copies of mouse Dax1 as a transgene show delayed testis development when the gene is expressed at high levels, but do not normally show sex reversal. Complete sex reversal occurs, however, when the transgene is tested against weak alleles of the sex-determining Y-chromosome gene Sry. These results show that DAX1 is largely, if not solely, responsible for dosage-sensitive sex reversal and provide a model for early events in mammalian sex determination, when precise levels and timing of gene expression are critical.

A molecular approach to sex determination in mammals

Mammalian sex determination occurs in the gonad of the developing embryo. This process is dependent on the Y-chromosome-encoded Sry gene that acts in the somatic cells of the genital ridge. The transient nature of Sry gene expression suggests that it acts as a switch from one cell fate to another. One of the roles of Sry is to initiate the differentiation of Sertoli cells, which are the first cell type of the testis to be formed. Two genes are thought to be important in Sertoli cell differentiation and function, Sox9, an Sry-related gene, and SF-1, a nuclear hormone receptor. Sox9 is expressed in Sertoli cells throughout development of the mouse embryo, and inactivating mutations in this gene in humans give rise to XY females. SF-1 is also expressed in Sertoli cells and is thought to activate the AMH gene--an early marker of these cells. DAX-1, an X-linked member of the nuclear hormone superfamily, is a candidate for a human condition in which duplication of regions of the X chromosome results in XY females. Expression of this gene during mouse development is associated with ovary development and is down-regulated in the differentiating testis. Mutations in DAX-1 in humans have shown that this gene is not necessary for testis development. The properties of the DAX-1 gene suggest that it is important in ovary determination and might therefore be antagonistic to the action of the Sry gene.

Steroidogenic factor 1 plays multiple roles in endocrine development and function

The nuclear hormone receptor family comprises a group of structurally related transcriptional regulators that mediate the actions of diverse ligands, including steroid hormones, thyroid hormone, vitamin D, and retinoids. The nuclear receptor family also contains members for which activating ligands have not been identified-the orphan nuclear receptors. One of these orphan nuclear receptors, steroidogenic factor 1 (SF-1), has emerged as an essential regulator of steroidogenic cell function within the adrenal cortex and gonads; SF-1 also plays important roles in reproduction at all three levels of the hypothalamic-pituitary-gonadal axis. First identified as a tissue-specific regulator of the transcription of the cytochrome P450 steroid hydroxylases, considerably broader roles for SF-1 were revealed by genetic studies in mice lacking SF-1 due to targeted gene disruption. These SF-1-knockout mice had agenesis of their adrenal glands and gonads, male-to-female sex reversal of their internal and external genitalia, impaired gonadotrope function, and agenesis of the ventromedial hypothalamic nucleus. These studies delineated essential roles of SF-1 in regulating endocrine differentiation and function at multiple levels. Despite these insights into roles of SF-1, the precise mechanisms by which SF-1 exerts its multiple effects remain to be determined. This review highlights experiments that have established SF-1 as a pivotal determinant of endocrine differentiation and function and identifies areas in which additional studies are needed to expand our understanding of SF-1 action.

Steroidogenic factor 1 and Dax-1 colocalize in multiple cell lineages: potential links in endocrine development

Mutations of the orphan nuclear receptors, steroidogenic factor 1 (SF-1) and DAX-1, cause complex endocrine phenotypes that include impaired adrenal development and hypogonadotrophic hypogonadism. These similar phenotypes suggest that SF-1 and DAX-1 act in the same pathway(s) of endocrine development. To explore this model, we now compare directly their sites of expression. In mouse embryos, SF-1 expression in the urogenital ridge and brain either preceded or coincided with Dax-1 expression, with coordinate expression thereafter in the adrenal cortex, testis, ovary, hypothalamus, and anterior pituitary. The striking colocalization of SF-1 and Dax-1 supports the model that they are intimately linked in a common pathway of endocrine development. The slightly earlier onset of SF-1 expression and its ability to bind specifically to a conserved sequence in the Dax-1 5'-flanking region suggested that SF-1 may activate Dax-1 expression. However, promoter activity of Dax-1 5'-flanking sequences did not require this potential SF-1-responsive element, and Dax-1 expression was unimpaired in knockout mice lacking SF-1, establishing that SF-1 is not required for Dax-1 gene expression in these settings. Although the precise mechanisms remain to be established and may be multifactorial, our results strongly suggest that these two orphan nuclear receptors interact in a common pathway of endocrine development.

Social loafing and identifiability: the mediating role of achievement goal orientations

The purpose of this investigation was to determine if differences in the tendency to exhibit social loafing is a function of achievement-goal orientation and identifiability. Ninety-six males drawn from 10th-grade physical education classes responded to the Task and Ego Orientation in Sport Questionnaire (Duda, 1992) prior to completing a 30-meter sprint task under three separate conditions: as an individual, in a team with individual performance identified, and in a team with individual performance not identified. Following a median split of the task and ego values reported, subjects were divided into high and low groups for both orientations. Sprint times were compared by means of a 2 x 2 x 3 ANOVA (task x ego x sprint condition) with repeated measures on the third factor. Findings revealed that individuals with a combined low task/high ego orientation were significantly slower in the nonidentifiable team condition than in the other two conditions, whereas high-task/low-ego-oriented individuals demonstrated consistent performance across all three conditions. While confirming that identifiability of performance is an important situational variable, the findings suggest that the dispositional factor of achievement orientation may interact to provide a more detailed explanation of the social loafing phenomenon.

Sox9 expression during gonadal development implies a conserved role for the gene in testis differentiation in mammals and birds

Heterozygous mutations in SOX9 lead to a human dwarfism syndrome, Campomelic dysplasia. Consistent with a role in sex determination, we find that Sox9 expression closely follows differentiation of Sertoli cells in the mouse testis, in experimental sex reversal when fetal ovaries are grafted to adult kidneys and in the chick where there is no evidence for a Sry gene. Our results imply that Sox9 plays an essential role in sex determination, possibly immediately downstream of Sry in mammals, and that it functions as a critical Sertoli cell differentiation factor, perhaps in all vertebrates.

Mouse Dax1 expression is consistent with a role in sex determination as well as in adrenal and hypothalamus function

Duplications of a chromosome Xp21 locus DSS (Dosage Sensitive Sex reversal) are associated with male to female sex reversal. An unusual member of the nuclear hormone receptor superfamily, DAX1, maps to the DSS critical region and is responsible for X-linked adrenal hypoplasia congenita. Here we describe the isolation of the mouse Dax1 gene and its pattern of expression during development. Expression was detected in the first stages of gonadal and adrenal differentiation and in the developing hypothalamus. Moreover, Dax1 expression is down-regulated coincident with overt differentiation in the testis, but persists in the developing ovary. Comparison of the predicted protein products of the human and mouse genes show that specific domains are evolving rapidly. Our results suggest a basis for adrenal insufficiency and hypogonadotropic hypogonadism in males affected by adrenal hypoplasia congenita and are consistent with a role for DAX1 in gonadal sex determination.

Reproducibility of blood pressure and heart rate reactivity: a meta-analysis

Reproducibilities of blood pressure and heart rate (HR) reactivity reported in studies assessing responses to the same laboratory stressors across occasions were reviewed with meta-analytic techniques. Changes in HR had the greatest reproducibility (r = .555), followed by systolic blood pressure (SBP) (.407) and diastolic blood pressure (DBP) (.348). Both SBP and HR response reproducibility was higher at shorter test-retest intervals, whereas DBP values varied unsystematically with length of test-retest interval. Older samples exhibited higher SBP and DBP reproducibility to stressors. SBP and DBP reproducibilities were better for tasks that did not make speech demands. The reliability of reactivity assessment was higher when based on three or more measurements. On the basis of available evidence, the drop in stress reproducibility, as test-retest interval increases, places limits on the viability of BP reactivity as a strong marker or risk factor for coronary heart disease.

Effects of goal-setting interventions on selected basketball skills: a single-subject design

The purpose of this investigation was to examine the effects of a goal-setting intervention program on selected components of basketball performance over the course of a competitive season. A multiple-baseline, single-subject design was used with baseline observations on various performance components (e.g., turnovers, rebounds), collected for four elite college basketball players during their first eight games of the season. At the midseason break, these players selected one aspect of their play that they felt would benefit from improvement. A goal-setting program was designed based on the goal attainment scaling procedure recommended by Smith (1988), whereby subjects generated numerical targets for their chosen components. Performance components were then assessed for the next eight games as they had been in the preintervention phase. Following the intervention, 3 of the 4 subjects showed consistent improvements in their targeted areas of performance. Also, there were no outcome changes in the performance components that weren't targeted by the subjects. The findings suggest that future studies may benefit from achieving greater ecological validity and utilizing alternative designs to the traditional nomothetic approaches which may tend to mask positive intervention effects on certain individuals.

Intensity and frequency dimensions of competitive state anxiety

This study reports a preliminary investigation of intensity and frequency of symptoms of competitive state anxiety. Forty-nine track and field athletes (27 males, 22 females) responded to a modified version of the Competitive State Anxiety Inventory-2 (CSAI-2) on four occasions during the period leading up to an important competition: 2 days, 1 day, 2 h and within 30 min of competing. The questionnaire included the existing CSAI-2 (intensity) scale as well as a frequency scale for each of the 27 items of the CSAI-2. The intensity and frequency dimensions of each of the CSAI-2-sub-scales were then compared between the four conditions by means of two-way analyses of variance (gender x time-to-competition). In the case of cognitive anxiety, time-to-event effects were observed for intensity and frequency for both males and females. The intensity of the response was significantly greater at the final stage of testing than it was 2 days before competition, while the frequency of the response increased progressively throughout the experimental period. This dissociative patterning for the cognitive anxiety dimensions is discussed in the light of Multidimensional Anxiety Theory predictions. For somatic anxiety, the time-to-event effects that emerged for intensity and frequency revealed that both values increased progressively as the time to compete neared, for both male and females. The results for self-confidence revealed no effects for intensity or frequency for either gender. The findings from structured follow-up interviews served to corroborate these quantitative findings by providing information that supported the conclusions drawn from the questionnaire data. In particular, the athletes reported that they experienced considerable increases in the frequency of intrusive anxiety cognitions. While these findings clearly need to be substantiated, they do provide evidence of the existence of an additional dimension of anxiety that may assist our understanding of this complex concept. The measurement of competitive state anxiety may benefit from this more detailed approach as opposed to the rather limited intensity-alone perspective.

Intensity and direction dimensions of competitive state anxiety and relationships with performance

This study examined relationships between intensity and direction dimensions of competitive state anxiety, and also relationships with beam performance in a sample of female gymnasts. The 48 gymnasts, whose ages ranged from 14 to 16 years, competed in a beam competition and were divided, via the median split technique, into poor performance and good performance groups. All the subjects completed a modified version of the Competitive State Anxiety Inventory-2 (CSAI-2) 10 min prior to performance. This inventory included the original intensity scale plus a direction scale in which subjects rated the degree to which the experienced intensity of each symptom was either facilitative of debilitative to subsequent beam performance. Analyses of variance showed no significant group differences on any of the CSAI-2 sub-component intensity scores, or on somatic anxiety and self-confidence direction scores. However, the good performance group reported their cognitive anxiety intensity as being more facilitating and less debilitating to performance than the poor performance group. Stepwise multiple-regression analyses showed that the only significant predictor of beam performance was self-confidence intensity. These findings support the proposal that sports performers' directional perceptions of their anxiety symptoms may provide further understanding of the competitive state anxiety response, and also emphasize the importance of self-confidence in predicting performance.

Influence of sequences in the long terminal repeat and flanking cell DNA on polyadenylation of retroviral transcripts

Readthrough transcripts are formed during retrovirus infection by polyadenylation of viral RNA in cellular sequences adjacent to the provirus. We have studied such transcripts in avian leukosis virus-infected cell clones containing a single provirus, either the wild type or one with an inactivating mutation in the poly(A) addition signal. All individual wild-type proviruses produced readthrough transcripts, implying that this property is not restricted to a few integration sites. The range of sizes of viral RNA in the mutant lacking a correct signal for poly(A) addition reflected both the occurrence of functional polyadenylation sites within flanking cell DNA and increased usage of cryptic sites within viral sequences.

Circular transcripts of the testis-determining gene Sry in adult mouse testis

Sry is expressed at higher levels in the adult testis, where no function has been determined, than in the genital ridge, its critical site of action. cDNA and 5' RACE clones isolated from testis or from Sry-transfected cell lines have an unusual structure, with 3' sequences located in a 5' position. RNAase protection assays and reverse transcription polymerase chain reactions confirmed that these unusual RNA molecules represent the most abundant transcript in testis. Furthermore, oligonucleotide hybridization and RNAase H digestion proved that these Sry RNA molecules are circular. Similar transcripts were detected in the testes of mice with Mus musculus musculus, Mus musculus domesticus, and Mus spretus Sry genes. The circular RNA is found in the cytoplasm but is not substantially bound to polysomes. We suggest that the circles arise from normal splicing processes as a consequence of the unusual genomic structure surrounding the Sry locus in the mouse.

Intensity and direction as dimensions of competitive state anxiety and relationships with competitiveness

This study examined differences in intensity and direction of symptoms of competitive state anxiety in high and low competitive subjects from the sports of rugby union, basketball, soccer, and field hockey. The 69 men were dichotomized via a median-split into high and low competitive groups based on their scores on the Sport Orientation Questionnaire. All subjects completed a modified version of the Competitive State Anxiety Inventory-2 30 minutes prior to competition. This inventory included the original intensity scale plus a direction scale on which subjects rated the extent the experienced intensity of each symptom was either facilitative or debilitative to subsequent performance. There were no significant group differences on intensity of cognitive anxiety or of somatic anxiety or on direction of somatic anxiety; however, the highly competitive group of 34 subjects reported their anxiety as more facilitative and less debilitative than the low competitive group (n = 35). This supports the proposal that sports performers' directional perceptions of their anxiety symptoms may provide further understanding of the competitive state-anxiety response.

Mechanism of transduction by retroviruses

Retroviruses can capture cellular sequences and express them as oncogenes. Capture has been proposed to be a consequence of the inefficiency of polyadenylation of the viral genome that allows the packaging of cellular sequences flanking the integrated provirus in virions; after transfer into virions, these sequences could be incorporated into the viral genome by illegitimate recombination during reverse transcription. As a test for this hypothesis, a tissue culture system was developed that mimics the transduction process and allows the analysis and quantitation of capture events in a single step. In this model, transduction of sequences adjacent to a provirus depends on the formation of readthrough transcripts and their transmission in virions and leads to various recombinant structures whose formation is independent of sequence similarity at the crossover site. Thus, all events in the transduction process can be attributed to the action of reverse transcriptase on readthrough transcripts without involving deletions of cellular DNA.

Physical characterisation of plasmids in a morpholine-degrading mycobacterium

The plasmid content of an environmental mycobacterium (MorG) which degrades morpholine (Mor+ phenotype) was investigated. The combination, in what appears to be a novel way, of restriction endonuclease digestion, gel electrophoresis and scanning densitometry permitted the resolution of mixed plasmid preparations into four distinct plasmids with sizes of 54 (approximately), 27.7, 22.8 and 22.6 kb. These plasmids were named pMOR1, 2, 3 and 4, respectively. The Mor+ phenotype was found to be unstable during acriflavin treatment. In four independently isolated Mor- mutants, plasmid pMOR2 was found to have acquired an insert of approximately 1.8 kb within a specific 5.9 kb BamHI fragment. It is concluded that pMOR2 is involved in the coding of the Mor+ phenotype.

Interrelationships among multidimensional competitive state anxiety components as a function of the proximity of competition

This study examined whether the relationship between the cognitive anxiety and somatic anxiety subscales of the Competitive State Anxiety Inventory-2 changes as a function of the proximity of a competition. On five separate occasions during the period prior to an important competition 87 subjects responded to the inventory. Intercorrelations between subscale scores suggested a progressive increase in the magnitude of the relationship between cognitive and somatic anxiety as the event approached. Findings support in a sporting context the hypothesis of covariance at times of high stress.

ABC of major trauma. Trauma of the spine and spinal cord--II

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ABC of major trauma. Trauma of the spine and spinal cord--I

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Performance of seven blood glucose testing systems at high altitude

Consumers and health care professionals expect blood glucose monitoring systems to consistently generate results that are close to actual blood glucose levels. Numerous environmental, physiologic, and operational factors can affect system performance, yielding results that are inaccurate or unpredictable. This study examined the effect of one factor--high altitude--on the performance of seven blood glucose monitoring systems. One of the systems overestimated blood glucose results; the other six systems underestimated blood glucose values (more than the expected variance). The findings of this study support previous reports of altered blood glucose monitoring system performance at high altitude. Diabetes educators can use this information when counseling consumers who reside or who plan to visit locations at high altitude.

Polyadenylation at correct sites in genome RNA is not required for retrovirus replication or genome encapsidation

RNA transcripts polyadenylated at sites derived from flanking cellular DNA (readthrough transcripts) make up about 15% of the viral RNA in cells infected with avian leukosis virus. To test the functionality of such transcripts, a virus was created by introducing two mutations into the AAUAAA polyadenylation signal of Rous-associated virus 1, converting it to AAGGAA. The replication of this virus was not greatly affected at any level. However, less than 1% of viral transcripts produced during mutant virus replication were cleaved and polyadenylated at the correct site within viral long terminal repeat-related sequence. These results imply that readthrough transcripts, which are produced during normal viral replication, are polyadenylated and packaged into virions as normal transcripts and can serve as RNA genomes in the next round of replication. These results show that polyadenylation within virus-related sequences is not a necessary requirement for virus replication and that readthrough transcripts have the necessary properties to be intermediates in the process of transduction of cellular sequences.

Analysis of expression and thermoregulation of the Yersinia pseudotuberculosis inv gene with hybrid proteins

A series of translational fusions between the Yersinia pseudotuberculosis inv locus and lacZ was constructed. Each Lac+ fusion strain expressed a hybrid protein containing invasin, the product of the inv locus, at its amino-terminal end. Analysis of these gene fusions allowed determination of the direction of translation of the inv gene. Previous studies of Y. pseudotuberculosis invasion have shown that entry into animal cells is temperature regulated. It is shown here that control of expression of the inv gene is also temperature regulated. phoA gene fusions to inv, when present in Y. pseudotuberculosis, were expressed at lower levels when bacteria were grown at 37 degrees C rather than at 28 degrees C. Similar fusions, in contrast, were regulated in a temperature-independent fashion in Escherichia coli, as was the wild-type inv gene. This implies that Y. pseudotuberculosis has chromosomally encoded trans-acting functions that normally thermoregulate expression of inv.