Rapid and efficient oligonucleotide synthesis with low reagent consumption via a new synthesis column design: preparation of fluorescent dye labelled primers for application in PCR

A low dead-volume, 40 nmole scale column was designed for automated, solid-support oligonucleotide synthesis. The LV40 columns are filled with 1000A, high-cross link polystyrene beads at the 40 nmole scale. Reducing the unoccupied volume and optimizing the column dimensions allows efficient and fast synthesis on existing commercial synthesizers with low reagent consumption. Three spectrally distinct fluorescent dyes were applied as phosphoramidites in the synthesis of PCR primers. Fluorescent labelled PCR products of the Mfd11 microsatellite locus were analyzed.

Serum electrolyte and blood gas changes after intrathecal and intravenous bolus injections of magnesium sulphate. An experimental study in a rat model

The effect of intrathecally administered magnesium sulphate on serum levels of magnesium, sodium, potassium, calcium and blood gas variables was studied in a rat model. Magnesium sulphate given intrathecally has previously been shown to produce segmental spinal blockade with no permanent neurological damage. The previous studies, however, had not investigated the possible systemic effects of the magnesium sulphate. The serum magnesium level increased significantly at 1 and 2 h after the intrathecal injection of both 6.3% and 12.6% magnesium sulphate (6.3%: 28% at 1 h, 24% at 2 h; 12.6%: 22% at 1 h, 16% at 2 h). These changes were not as great as occurred when the same dose of magnesium sulphate was administered intravenously. In all cases, the serum magnesium had returned to normal by 24 h. There were no significant changes in calcium, sodium or potassium levels, nor in arterial blood gas variables. These results show that intrathecally administered magnesium sulphate has little effect on electrolyte homeostasis.

Case study: trauma-related hallucinations

Proper differential diagnosis of psychiatric disorders with psychotic symptoms is imperative, as the treatment implications of the various conditions are quite different. A case study of a 5-year-old abused child with posttraumatic stress disorder is presented to illustrate some of the characteristic features of psychotic symptoms in traumatized children. Literature reviewed suggests that trauma-related hallucinations frequently contain content which is related to children's life experiences, are exacerbated by "triggers" and safety concerns, resolve with psychotherapy or psychosocial interventions, and are resistant to standard neuroleptic treatments. They are also associated with unique clinical, familial, developmental, and psychobiological correlates, and they require multifaceted treatment interventions.

The corticotropin-releasing hormone challenge in depressed abused, depressed nonabused, and normal control children

Hypothalamic-pituitary-adrenal (HPA) axis disturbances in depressed children with a history of abuse were examined. Thirteen depressed abused, 13 depressed nonabused, and 13 normal control children were given 1.0 microgram/kg of human corticotropin-releasing hormone (CRH) intravenously. Blood samples for corticotropin (ACTH) and cortisol were obtained at nine intervals. When compared to depressed nonabused and normal control children, depressed abused children had significantly greater peak, total, and net ACTH secretion post-CRH. Increased ACTH secretion was only observed in depressed abused children experiencing ongoing chronic adversity (marital violence, emotional abuse, poverty, lack of supports). The pattern of findings of the depressed abused children experiencing ongoing adversity parallels the pattern of HPA axis dysregulation reported in animal studies of chronic stress. They add to a growing body of literature suggesting measures of past trauma and current adversity are important sources of variability in psychobiological correlates of major depression.

Determination of the secondary structure and global topology of the 44 kDa ectodomain of gp41 of the simian immunodeficiency virus by multidimensional nuclear magnetic resonance spectroscopy

The gp41 protein of the human (HIV) and simian (SIV) immunodeficiency viruses is part of the envelope glycoprotein complex gp41/gp120 which plays an essential role in viral infection. We present a multidimensional NMR study on the trimeric 44 kDa soluble ectodomain of SIV gp41 (e-gp41), comprising residues 27 to 149. Despite the large molecular weight and very limited spectral dispersion, complete backbone 1H, 13C, 13CO and 15N assignments have been made using a combination of triple resonance experiments on uniformly 13C/15N and 2H/13C/15N-labeled samples. The secondary structure of SIV e-gp41, derived on the basis of 13C chemical shifts, NH exchange rates, medium range nuclear Overhauser enhancements (NOE), and 3JHNalpha coupling constants, consists of a 49 residue helix at the N terminus (residues 29 to 77) and a 40 residue helix at the C terminus (residues 108 to 147), connected by a 30 residue loop which does not display any of the characteristics of regular secondary structure. The cross-peak intensities of the loop region in scalar correlation experiments suggests that it is more mobile than the core helical regions. The presence, however, of numerous long range NOEs, both intra and inter-subunit, within the loop indicates that it adopts a well-defined structure in which the loops from the three subunits interact with each other. Based on a number of long range intra and inter-subunit NOEs, a topological model is presented for the symmetric SIV e-gp41 trimer in which the N-terminal helices are packed within the protein interior in a parallel trimeric coiled-coil arrangement, while the C-terminal helices are located on the protein exterior, oriented antiparallel to the N-terminal helices.

Baseline thyroid hormones in depressed and non-depressed pre- and early-pubertal boys and girls

OBJECTIVE

To examine baseline thyroid hormones in a large group of well-characterized pre- and early-pubertal boys and girls who met criteria for major depressive disorder (MDD) and a comparison group of normal children without psychiatric disorders.

METHODS

45 children with MDD (10.6 years +/- 1.4 year) and 56 healthy controls (10.0 +/- 1.7 year) who participated in a large, psychobiologic protocol are included in this report. As part of the screening for eligibility, baseline samples were drawn for thyroxine (T4), triiodothyronine (T3) uptake, and thyroid stimulating hormone (TSH). Free thyroxine index (FTI) also was computed.

RESULTS

Between-group analyses were carried out controlling for various demographic variables significantly related to thyroid hormones [e.g. age, gender, body mass index (BMI) and their interactions]. For many hormones there were significant effects for age and gender. For T4, MDD boys had lower T4 compared with boys in the normal group. No differences were noted between MDD girls and normal girls. For TSH, MDD boys had lower concentrations compared with normal boys while no differences were noted in girls. For T3 uptake, the MDD group had lower uptake compared with the normal group. For FTI, there were no group differences. Similar to most studies of adults with depression, all our subjects were euthyroid. Unlike the adult studies, we found lower T4 concentrations in the MDD group rather than higher. Group differences in thyroid hormones were noted primarily in boys. The large sample size of this study allowed for the control of multiple variables, which has not been done in past studies. Without such controls, true findings may be masked in other studies of depression. Thus, our findings suggest the possibility of developmental differences in the relation of thyroid hormone and depression.

The extracellular domain of immunodeficiency virus gp41 protein: expression in Escherichia coli, purification, and crystallization

The env gene of SIV and HIV-1 encodes a single glycoprotein gp 160, which is processed to give a noncovalent complex of the soluble glycoprotein gp120 and the transmembrane glycoprotein gp41. The extracellular region (ectodomain), minus the N-terminal fusion peptide, of gp41 from HIV-1 (residues 27-154) and SIV (residues 27-149) have been expressed in Escherichia coli. These insoluble proteins were solubilized and subjected to a simple purification and folding scheme, which results in high yields of soluble protein. Purified proteins have a trimeric subunit composition and high alpha-helical content, consistent with the predicted coil-coil structure. SIV gp41 containing a double cysteine mutation was crystallized. The crystals are suitable for X-ray structure determination and, preliminary analysis, together with additional biochemical evidence, indicates that the gp41 trimer is arranged as a parallel bundle with threefold symmetry.

Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL): initial reliability and validity data

OBJECTIVE

To describe the psychometric properties of the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL) interview, which surveys additional disorders not assessed in prior K-SADS, contains improved probes and anchor points, includes diagnosis-specific impairment ratings, generates DSM-III-R and DSM-IV diagnoses, and divides symptoms surveyed into a screening interview and five diagnostic supplements.

METHOD

Subjects were 55 psychiatric outpatients and 11 normal controls (aged 7 through 17 years). Both parents and children were used as informants. Concurrent validity of the screen criteria and the K-SADS-PL diagnoses was assessed against standard self-report scales. Interrater (n = 15) and test-retest (n = 20) reliability data were also collected (mean retest interval: 18 days; range: 2 to 36 days).

RESULTS

Rating scale data support the concurrent validity of screens and K-SADS-PL diagnoses. Interrater agreement in scoring screens and diagnoses was high (range: 93% to 100%). Test-retest reliability kappa coefficients were in the excellent range for present and/or lifetime diagnoses of major depression, any bipolar, generalized anxiety, conduct, and oppositional defiant disorder (.77 to 1.00) and in the good range for present diagnoses of posttraumatic stress disorder and attention-deficit hyperactivity disorder (.63 to .67).

CONCLUSION

Results suggest the K-SADS-PL generates reliable and valid child psychiatric diagnoses.

Refined solution structure and backbone dynamics of HIV-1 Nef

The tendency of HIV-1 Nef to form aggregates in solution, particularly at pH values below 8, together with its large fraction of highly mobile residues seriously complicated determination of its three-dimensional structure, both for heteronuclear solution NMR (Grzesiek et al., 1996a, Nat Struct Biol 3:340-345) and for X-ray crystallography (Lee et al., 1996, Cell 85:931-942). Methods used to determine the Nef structure by NMR at pH 8 and 0.6 mM concentration are presented, together with a detailed description of Nef's secondary and tertiary structure. The described techniques have general applicability for the NMR structure determination of proteins that are aggregating and/or have limited stability at low pH values. Extensive chemical shift assignments are reported for backbone and side chain 1H, 13C, and 15N resonances of the HIV-1 Nef deletion mutants NEF delta 2-39, NEF delta 2-39, delta 159-173, and of NEF delta 2-39, delta 159-173 in complex with the SH3 domain of the Hck tyrosine protein kinase. Besides a type II polyproline helix, Nef's structure consists of three alpha-helices, a 3(10) helix, and a five-stranded anti-parallel beta-sheet. The analysis of 15N relaxation parameters of the backbone amide sites reveals that all the secondary structure elements are non-mobile on the picosecond to nanosecond and on the millisecond time scale. A large number of slowly exchanging amide protons provides evidence for the stability of the Nef core even on the time scale of hours. Significant internal motions on the ps to ns time scale are detected for residues 60 to 71 and for residues 149 to 180, which form solvent-exposed loops. The residues of the HIV-1 protease cleavage site (W57/L58) do not exhibit large amplitude motions on the sub-nanosecond time scale, and their side chains insert themselves into a hydrophobic crevice formed between the C-terminus of helix 1 and the N-terminus of helix 2. A refined structure has been determined based on additional constraints for side-chain and backbone dihedral angles derived from a large number of three-bond J-coupling and ROE data.

Reluctance of paramedics and emergency medical technicians to perform mouth-to-mouth resuscitation

Recently, a reluctance of lay and medical personnel to perform mouth-to-mouth resuscitation (MMR) in hospital and community settings has been documented, with 45% of respondents declining to perform MMR on a stranger. In the present study, we examined whether the perceived risk and fear of contracting infectious diseases diminishes the willingness of paramedics and emergency medical technicians (EMTs) to perform MMR. Seventy-seven EMTs and 27 paramedics responded to a questionnaire, administered by one of two physicians, containing mock cardiac arrest scenarios that were designed to assess willingness to perform MMR as a citizen responder. Faced with a situation in which an adult stranger required MMR, 57% of the participating EMTs and all of the paramedics stated that they would refuse to perform MMR. None of the paramedics and only 32.5% of the EMTs stated that they would perform MMR on a man in a gay neighborhood. In addition, 23% of the EMTs and 37% of the paramedics indicated that they would refuse to perform MMR on a child. White respondents were more willing than nonwhite respondents to perform MMR. Twenty-nine percent of the prehospital-care providers had been in situations requiring MMR in the community, and 40% either had walked away or did only external compression. Of those participating paramedics and EMTs who had performed MMR in emergency situations, only 45% indicated that they would do so again. The respondents indicated that they would not be willing to administer MMR because of the fear of contracting infectious agents, especially the human immunodeficiency virus. Despite the proven effectiveness of MMR in saving lives, paramedics and EMTs are highly reluctant to perform MMR as citizen responders. Their perceived risks of contracting infectious agents during MMR are high, despite the low actual risks. We recommend that instruction in cardiopulmonary resuscitation for providers of pre-hospital care, the medical community, and the general public should emphasize the benefits of providing MMR, the actual low risks of contracting infectious diseases during administration of MMR, and the use of widely available and effective barrier masks to minimize any risks due to administration of MMR.

The Screen for Child Anxiety Related Emotional Disorders (SCARED): scale construction and psychometric characteristics

OBJECTIVE

To develop a reliable and valid child and parent self-report instrument to screen children with anxiety disorders.

METHOD

An 85-item questionnaire was administered to 341 outpatient children and adolescents and 300 parents. Utilizing item analyses and factor analyses, the original scale was reduced to 38 items. A subsample of children (n = 88) and parents (n = 86) was retested an average of 5 weeks (4 days to 15 weeks after the initial screening.

RESULTS

The child and parent Screen for Child Anxiety Related Emotional Disorders (SCARED) both yielded five factors: somatic/panic, general anxiety, separation anxiety, social phobia For the total score and each of the five factors, both the child and parent SCARED demonstrated good internal consistency (alpha = .74 to .93), test-retest reliability (intraclass correlation coefficients = .70 to .90), discriminative validity (both between anxiety and other disorders and within anxiety disorders), and moderate parent-child agreement (r = .20 to .47, p < .001, all correlations).

CONCLUSIONS

The SCARED shows promise as a screening instrument for anxiety disorders. Future studies using the SCARED in community samples are indicated.

Falls in construction: injury rates for OSHA-inspected employers before and after citation for violating the Washington State Fall Protection Standard

This study examined the relationship between Washington's fall protection standard and injuries in construction workers. Workers' compensation claim rates for falls were examined for employers that were cited for violating the standard over the 1991-1992 period. Fall injury rates for the periods before and after inspections were compared. Claims for a control group of employers that had not been cited were also examined. For the 784 cited employers, the claim rate for compensable fall injuries decreased from 1.78 to 1.39 per 200,000 hours worked for the one-year periods before and after inspection. For the control group (n = 8,301), the claim rate decreased from 1.04 to 0.95 per 200,000 hours. Cited employers were 2.3 times as likely as control employers (p < 0.0001) to experience a claim rate reduction, after adjustment for employer size and type of business. Results suggested that industry-wide fall injury rates might be expected to decrease if more employers were inspected.

Intracaval extension of germ cell carcinoma: diagnosis via endovascular biopsy and a review of the literature

We report a case of testicular carcinoma invading the inferior vena cava. Tumor invasion was diagnosed via endovascular biopsy. This is the first known report of a diagnosis of this entity using endovascular biopsy. We also review the literature on diagnosis and management of inferior vena caval involvement by testicular cancer.

Injuries due to assaults on psychiatric hospital employees in Washington State

In order to estimate rates and identify risk factors for assaults on employees of a state psychiatric hospital, we examined workers' compensation claims, hospital-recorded incident reports, and data collected in a survey of ward staff. Results revealed 13.8 workers' compensation claims due to assault per 100 employees per year. Assaults were responsible for 60% of total claims. Incident reports revealed 35 injuries due to assault per 100 employees per year. Survey data revealed 415 injuries due to assault per 100 employees per year. Of the respondents, 73% reported at least a minor injury during the past year. Assault management training in the past year was associated with less severe injuries. Working in isolation, the occupation of mental health technician, and working on the geriatric-medical hospital unit were associated with more severe injuries during the past year. Assaults on staff in psychiatric hospitals represent a significant and underrecognized occupational hazard.

Childhood and adolescent depression: a review of the past 10 years. Part II

OBJECTIVE

To review the literature of the past decade covering the assessment, treatment, and prevention of early-onset major depressive disorder (MDD) and dysthymic disorder (DD).

METHOD

A computerized search for articles published during the past decade was made, and selected studies are presented.

RESULTS

Diagnostic systems and standardized interviews have been developed to reliably assess and diagnose early-onset MDD and DD. To data, few controlled psychotherapeutic trials, in particular cognitive-behavioral therapy (CBT), and one study using fluoxetine have been shown to be efficacious in the acute management of early-onset MDD. While studies of tricyclic antidepressants have shown no difference between medication and placebo, these studies are inconclusive because of the inclusion of small samples and other methodological issues. CBT may also be useful for the prevention of MDD. No studies have been published on maintenance treatment of MDD or the treatment of early-onset DD.

CONCLUSIONS

It appears that both pharmacological and psychotherapeutic interventions have a role in the acute treatment of MDD. However, further research on the separate and combined efficacy of these treatments for the acute treatment, maintenance, and prevention of early-onset MDD and DD is needed. The impact of comorbidity and psychosocial consequences of early-onset depression also emphasize the importance of utilizing a multimodal approach to treatment.

Antibody reactivity profiles following immunization with diverse peptides of the PERB11 (MIC) family

PERB11 (MIC) is a gene family possessing multiple copies located within the MHC. Structurally, PERB11 is related to the MHC class I, neonatal IgG Fc receptor (FcRn) and Zn-alpha 2-glycoprotein molecules. The MHC class I family is complex in terms of its genomic arrangement, expression and function, and available evidence suggests that the PERB11 family may be similarly complex. We have adopted an approach to study the expression of such complex gene families by immunizing with multiple peptides and by screening the resulting antibodies against a large range of tissues. The amino acid sequences of PERB11.1 and PERB11.2 as well as those of other related molecules were analysed and compared. Peptides were chosen for immunization based upon (i) loop formation within the equivalent known structure of the MHC class I molecules; (ii) immunogenicity by computer analysis; and (iii) evolutionary relationships. Antibodies in serum from immunized rabbits bound to three out of six peptides used for immunization. ELISA and immunoprecipitation demonstrated binding both to the peptides and to the PERB11.2 recombinant protein. By immunofluorescent staining of various tissues of several species, the three antisera generated overlapping profiles of activity. These included reactions with kidney, small and large intestine, oesophagus, testis, ovary and human neutrophils. This is the first description of antibodies induced by the PERB11 peptides. The extreme complexity of these profiles requires further investigation, but may be explained in terms of antibodies against diverse products of the PERB11 gene family and/or related molecules.

Childhood and adolescent depression: a review of the past 10 years. Part I

OBJECTIVE

To qualitatively review the literature of the past decade covering the epidemiology, clinical characteristics, natural course, biology, and other correlates of early-onset major depressive disorder (MDD) and dysthymic disorder (DD).

METHOD

A computerized search for articles published during the past 10 years was made and selected studies are presented.

RESULTS

Early-onset MDD and DD are frequent, recurrent, and familial disorders that tend to continue into adulthood, and they are frequently accompanied by other psychiatric disorders. These disorders are usually associated with poor psychosocial and academic outcome and increased risk for substance abuse, bipolar disorder, and suicide. In addition, DD increases the risk for MDD. There is a secular increase in the prevalence of MDD, and it appears that MDD is occurring at an earlier age in successive cohorts. Several genetic, familial, demographic, psychosocial, cognitive, and biological correlates of onset and course of early-onset depression have been identified. Few studies, however, have examined the combined effects of these correlates.

CONCLUSIONS

Considerable advances have been made in our knowledge of early-onset depression. Nevertheless, further research is needed in understanding the pathogenesis of childhood mood disorders. Toward this end, studies aimed at elucidating mechanisms and interrelationships among the different domains of risk factors are needed.

Emphysematous cystitis and pyelitis in a diabetic renal transplant recipient

Emphysematous cystitis is a rare complication of urinary tract infection. Patients with diabetes mellitus, neurogenic bladder, bladder outlet obstruction, and recurrent urinary tract infection are at increased risk for the disease. We present a case of emphysematous cystitis and pyelitis in a diabetic renal transplant recipient. He was treated with antibiotics alone with complete clinical and radiologic resolution. The clinical course was benign, as described in most patients. The prognosis of emphysematous cystitis is good after early diagnosis and prompt treatment with appropriate antibiotics, blood glucose control, and adequate urinary drainage.

The relationship between longitudinal clinical course and sleep and cortisol changes in adolescent depression

This study examined the relationship between longitudinal clinical course and sleep and cortisol findings in adolescent unipolar major depressive disorder (MDD). Subjects were 28 adolescents (15.4 +/- 1.3 years) systematically diagnosed with unipolar MDD and 35 group-matched normal controls who participated in EEG sleep and neuroendocrine studies. Follow-up clinical assessments were conducted 7.0 +/- 0.5 years later in 94% of the original cohort. Although initial group comparisons failed to show significant differences in biologic measures, analyses incorporating clinical follow-up reveal that changes in sleep and cortisol measures are associated with differential longitudinal course. Normal controls who would develop depression after the biologic studies had shown significantly higher density of rapid eye movements (REM) and a trend for reduced REM latency compared to controls with no psychiatric disorder at follow-up. Depressed subjects with a recurrent unipolar course showed a trend towards elevated plasma cortisol near sleep onset compared to MDD subjects with no further episodes during the follow-up interval.