Transthyretin: a choroid plexus-specific transport protein in human brain. The 1986 S. Weir Mitchell award

Plasma transthyretin (TTR, formerly called prealbumin) is a 55-kd protein that participates in the plasma transport of both thyroxine and retinol (vitamin A). TTR concentrations are disproportionately high in human ventricular CSF, suggesting that TTR is either selectively transported across or synthesized de novo within the blood-CSF barrier. To address this question, we adopted a molecular genetic approach; after isolating a cDNA clone encoding human TTR, we previously demonstrated specific TTR messenger RNA (mRNA) synthesis in rat choroid plexus. We have now extended these investigations to the human brain. Northern analysis of postmortem brain homogenates revealed abundant TTR mRNA in choroid plexus, but not in cerebellum or cerebral cortex. Choroid plexus mRNA was readily translated into TTR preprotein in an in vitro translation system. An immunocytochemical survey of human postmortem brain sections revealed the presence of TTR protein specifically and uniquely in the cytoplasm of choroid plexus epithelial cells; these results were corroborated at the mRNA level by an extensive survey of whole rat-brain sections by in situ hybridization. Therefore, within the mammalian CNS, TTR is the first known protein synthesized solely by the choroid plexus, suggesting a special role for TTR in the brain or CSF. Whether this function differs from its established plasma transport functions is presently unknown.

Genome-wide gene expression profiles of the developing mouse hippocampus

We have analyzed the developmental molecular programs of the mouse hippocampus, a cortical structure critical for learning and memory, by means of large-scale DNA microarray techniques. Of 11,000 genes and expressed sequence tags examined, 1,926 showed dynamic changes during hippocampal development from embryonic day 16 to postnatal day 30. Gene-cluster analysis was used to group these genes into 16 distinct clusters with striking patterns that appear to correlate with major developmental hallmarks and cellular events. These include genes involved in neuronal proliferation, differentiation, and synapse formation. A complete list of the transcriptional changes has been compiled into a comprehensive gene profile database (http://BrainGenomics.Princeton.edu), which should prove valuable in advancing our understanding of the molecular and genetic programs underlying both the development and the functions of the mammalian brain.

Characterization of a zinc-dependent transcriptional activator from Arabidopsis

The C2-H2 zinc-finger is a widely occurring DNA binding motif, usually present as tandem repeats. The majority of C2-H2 zinc-finger proteins that have been studied are derived from animals. Here, we characterize a member of a distinct class of plant C2-H2 zinc-finger proteins in detail. A cDNA clone encoding a DNA binding protein from Arabidopsis was isolated by SouthWestern screening. The protein, termed ZAP1 (Zinc-dependent Activator Protein-1), is encoded by a single copy gene, which is expressed to similar levels in root and flower, to a somewhat lower level in stem and to low levels in leaf and siliques. The optimal binding site was determined by random binding site selection, and the consensus sequence found is CGTTGACCGAG. The homology between ZAP1 and other DNA binding proteins is restricted to a repeated region of a stretch of 24 highly conserved amino acids followed by a zinc-finger motif (C-X4-C-X22-23-H-X1-H). The C-terminal zinc-finger region is essential for DNA binding, whereas deletion of the N-terminal one resulted in 2.5-fold reduced binding affinity. Binding of ZAP1 to DNA was abolished by metal-chelating agents. The activation domain as determined in yeast is adjacent to and possibly overlapping with the DNA binding domain. Particle bombardment experiments with plant cells showed that ZAP1 increases expression of a gusA reporter gene that is under control of ZAP1 binding sites. We conclude that ZAP1 is a plant transcriptional activator with a C2-H2 zinc-finger DNA binding domain.

Chronic restraint stress and chronic corticosterone treatment modulate differentially the expression of molecules related to structural plasticity in the adult rat piriform cortex

Stress and stress-related hormones induce structural changes in neurons of the adult CNS. Neurons in the hippocampus, the amygdala and the prefrontal cortex undergo neurite remodeling after chronic stress. In the hippocampus some of these effects can be mimicked with chronic administration of adrenal steroids. These changes in neuronal structure may be mediated by certain molecules related to plastic events such as the polysialylated form of the neural cell adhesion molecule (PSA-NCAM). The expression of PSA-NCAM persists in the adult hippocampus and it is up-regulated after chronic stress. The piriform cortex also displays considerable levels of PSA-NCAM during adulthood and indirect evidence suggests that it may also be the target of stress and stress related-hormones. Using immunohistochemistry we have studied the expression of PSA-NCAM and doublecortin (DCX; another protein implicated in neuronal structural plasticity) in the piriform cortex of adult rats subjected either to 21 days of chronic restraint stress or to oral corticosterone administration during the same period. Our results indicate that chronic stress and chronic corticosterone administration have differential effects on the expression of PSA-NCAM and DCX. While chronic stress increases the number of PSA-NCAM- and DCX-immunoreactive cells in the piriform cortex layer II, chronic corticosterone administration decreases these numbers. These findings indicate that stress and adrenal steroids affect the piriform cortex and suggest that in this region, as in the hippocampus, they may induce structural changes. This is a potential mechanism by which stress and corticosterone modulate functions of this limbic region, such as its participation in olfactory memory.

On-line monitoring of radiotherapy beams: experimental results with proton beams

Proton radiotherapy is a powerful tool in the local control of cancer. The advantages of proton radiotherapy over gamma-ray therapy arise from the phenomenon known as the Bragg peak. This phenomenon enables large doses to be delivered to well-defined volumes while sparing surrounding healthy tissue. To fully realize the potential of this technique the location of the high-dose volume must be controlled very accurately. An imaging system was designed and tested to monitor the positron-emitting activity created by the beam as a means of verifying the beam's range, monitoring dose, and determining tissue composition. The prototype imaging system consists of 12 pairs of cylindrical BGO detectors shielded in lead. Each crystal was 1.9 cm in diameter, 5.0 cm long, and separated by 0.5 cm from other detectors in the row. These are arranged in two rows, 60 cm apart, with the proton beam and tissue phantoms half-way between and parallel to the detector rows. Experiments were conducted with 150 MeV continuous and macro-pulsed proton beams which had beam currents ranging from 0.14 nA to 1.75 nA. The production and decay of short-lived isotopes, 15O and 14O, was studied using 1 min irradiations with a continuous beam. These isotopes provide a significant signal on short time scales, making on-line imaging possible. Macro-pulsed beams, having a period of 10 s, were used to study on-line imaging and the production and decay of long-lived isotopes, 13N, 11C, and 18F. Decay data were acquired and on-line images were obtained between beam pulses and indicate that range verification is possible, for a 150 MeV beam, after one beam pulse, to within the 1.2 cm resolution limit of the imaging system. The dose delivered to the patient may also be monitored by observing the increase in the number of coincidence events detected between successive beam pulses. Over 80% of the initial positron-emitting activity is from 15O while the remainder is primarily 11C, 13N, 14O with traces of 18F, and 10C. Radioisotopic imaging may also be performed along the beam path by fitting decay data collected after the treatment is complete. Using this technique, it is shown that variations in elemental composition in inhomogenous treatment volumes may be identified and used to locate anatomic landmarks. Radioisotopic imaging also reveals that 14O is created well beyond the Bragg peak, apparently by secondary neutrons.

Integrating the Epigenome to Identify Drivers of Hepatocellular Carcinoma

Disruption of epigenetic mechanisms has been intimately linked to the etiology of human cancer. Understanding how these epigenetic mechanisms (including DNA methylation [5mC], hydroxymethylation [5hmC], and histone post-translational modifications) work in concert to drive cancer initiation and progression remains unknown. Hepatocellular carcinoma (HCC) is increasing in frequency in Western countries but lacks efficacious treatments. The epigenome of HCC remains understudied. To better understand the epigenetic underpinnings of HCC, we performed a genome-wide assessment of 5mC, 5hmC, four histone modifications linked to promoter/enhancer function (H3K4me1, H3K27ac, H3K4me3, and H3K27me3), and transcription across normal, cirrhotic, and HCC liver tissue. Implementation of bioinformatic strategies integrated these epigenetic marks with each other and with transcription to provide a comprehensive epigenetic profile of how and when the liver epigenome is perturbed during progression to HCC. Our data demonstrate significant deregulation of epigenetic regulators combined with disruptions in the epigenome hallmarked by profound loss of 5hmC, locus-specific gains in 5mC and 5hmC, and markedly altered histone modification profiles, particularly remodeling of enhancers. Data integration demonstrates that these marks collaborate to influence transcription (e.g., hyper-5hmC in HCC-gained active enhancers is linked to elevated expression) of genes regulating HCC proliferation. Two such putative epigenetic driver loci identified through our integrative approach, COMT and FMO3, increase apoptosis and decrease cell viability in liver-derived cancer cell lines when ectopically re-expressed. Conclusion: Altogether, integration of multiple epigenetic parameters is a powerful tool for identifying epigenetically regulated drivers of HCC and elucidating how epigenome deregulation contributes to liver disease and HCC.

Fear learning transiently impairs hippocampal cell proliferation

We sought to determine whether contextual fear conditioning, a hippocampal-dependent task, would affect neurogenesis in the dentate gyrus of the hippocampus, and if so, to identify which aspect of the training experience accounts for the change. The immediate shock deficit paradigm was used, together with bromodeoxyuridine immunohistochemistry, to isolate the contribution of different aspects of contextual fear conditioning to neurogenesis. Contextual fear learning caused a 33% decrease in the number of proliferating cells that was anatomically restricted to the dentate gyrus with no change in cell survival or differentiation. This attenuation was not related to exposure to the conditioned stimulus alone, the footshock unconditioned stimulus alone, or the expression of fear to the context after training. Instead, the effect of context conditioning on cell proliferation appears to be specifically due to the formation of an association between the context and shock during training, an amygdala dependent function.

Glucocorticoids and histone deacetylase inhibitors cooperate to block the invasiveness of basal-like breast cancer cells through novel mechanisms

Aggressive cancers often express E-cadherin in cytoplasmic vesicles rather than on the plasma membrane and this may contribute to the invasive phenotype of these tumors. Therapeutic strategies are not currently available that restore the anti-invasive function of E-cadherin in cancers. MDA-MB-231 cells are a frequently used model of invasive triple-negative breast cancer, and these cells express low levels of E-cadherin that is mislocalized to cytoplasmic vesicles. MDA-MB-231 cell lines stably expressing wild-type E-cadherin or E-cadherin fused to glutathione S-transferase or green fluorescent protein were used as experimental systems to probe the mechanisms responsible for cytoplasmic E-cadherin localization in invasive cancers. Although E-cadherin expression partly reduced cell invasion in vitro, E-cadherin was largely localized to the cytoplasm and did not block the invasiveness of the corresponding orthotopic xenograft tumors. Further studies indicated that the glucocorticoid dexamethasone and the highly potent class I histone deacetylase (HDAC) inhibitor largazole cooperated to induce E-cadherin localization to the plasma membrane in triple-negative breast cancers, and to suppress cellular invasion in vitro. Dexamethasone blocked the production of the cleaved form of the CDCP1 (that is, CUB domain-containing protein 1) protein (cCDCP1) previously implicated in the pro-invasive activities of CDCP1 by upregulating the serine protease inhibitor plasminogen activator inhibitor-1. E-cadherin preferentially associated with cCDCP1 compared with the full-length form. In contrast, largazole did not influence CDCP1 cleavage, but increased the association of E-cadherin with γ-catenin. This effect on E-cadherin/γ-catenin complexes was shared with the nonisoform selective HDAC inhibitors trichostatin A (TSA) and vorinostat (suberoylanilide hydroxamic acid, SAHA), although largazole upregulated endogenous E-cadherin levels more strongly than TSA. These results demonstrate that glucocorticoids and HDAC inhibitors, both of which are currently in clinical use, cooperate to suppress the invasiveness of breast cancer cells through novel, complementary mechanisms that converge on E-cadherin.

Wnt ligand expression in malignant melanoma: pilot study indicating correlation with histopathological features

AIMS

Secreted Wnt ligands are key proteins regulating cell-cell interactions and cell growth and differentiation. These proteins, along with other components of the Wnt signalling pathway, are involved in the malignant transformation of various human cancers, including malignant melanoma. This study defines the expression of several members of the Wnt ligand family and correlates their expression with histological characteristics.

METHODS

The expression of Wnt2, Wnt5a, Wnt5b, Wnt7b, and Wnt10b was defined by in situ, antisense RNA hybridisation of paraffin wax embedded sections of benign naevi and malignant melanoma. Immunoperoxidase based antibody staining was used to define the expression of frizzled (Fz) receptors.

RESULTS

All naevi tested strongly expressed Wnt2, Wnt5a, Wnt7b, and Wnt10b. Melanomas characterised by small, uniform cells expressed each of the Wnts in a pattern similar to that seen for benign naevi. In contrast, melanomas characterised by large, pleomorphic cells expressed Wnt10b but did not express Wnt2 and had low levels of expression of Wnt5a. Expression of Wnt7b was variable in these melanomas. Fz receptor expression was present at a low level in normal epithelium and all naevi and melanomas.

CONCLUSIONS

The expression pattern of Wnt ligands in malignant melanoma correlates with histopathological features and may provide a basis for the molecular classification of this disease.

Chromatin remodeling and circadian control: master regulator CLOCK is an enzyme

The molecular machinery that governs circadian rhythmicity is based on clock gene products organized in regulatory feedback loops. Recently, we have shown that CLOCK, a master circadian regulator, has histone acetyltransferase activity essential for clock gene expression. The Lys-14 residue of histone H3 is a preferential target of CLOCK-mediated acetylation. As the role of chromatin remodeling in eukaryotic transcription is well recognized, this finding identified unforeseen links between histone acetylation and cellular physiology. Indeed, we have shown that the enzymatic function of CLOCK drives circadian control. We reasoned that CLOCK's acetyltransferase activity could also target nonhistone proteins, a feature displayed by other HATs. Indeed, CLOCK also acetylates a nonhistone substrate: its own partner, BMAL1. This protein undergoes rhythmic acetylation in the mouse liver, with a timing that parallels the down-regulation of circadian transcription of clock-controlled genes. BMAL1 is specifically acetylated on a unique, highly conserved Lys-537 residue. This acetylation facilitates recruitment of the repressor CRY1 to BMAL1, indicating that CLOCK may intervene in negative circadian regulation. Our findings reveal that the enzymatic interplay between two clock core components is crucial for the circadian machinery.

Factors influencing the diagnosis and treatment of periodontal disease by dental practitioners in Victoria

BACKGROUND

Healthy periodontal tissues are essential to overall dental health. Therefore, the detection and management of periodontal disease is an integral part of general dental practice. The aim of this study was to investigate confidence in diagnosis and management of periodontal disease by general dental practitioners (GDPs), assess if the Dental Practice Board guidelines on periodontal record keeping are being addressed, and, if necessary, try to find ways of improving the periodontal knowledge of GDPs.

METHODS

A survey assessing practitioner confidence in diagnosing and treating periodontal disease was sent to a random selection of 550 dental care providers registered with the Dental Practice Board of Victoria.

RESULTS

Two hundred and eighty five (51.8 per cent) of questionnaires were returned completed. It was found that 79.7 per cent of the sampled population screened all new patients for periodontal disease. The majority of respondents felt confident to diagnose and treat gingivitis and initial periodontitis. However, only 61.9 per cent felt confident to diagnose aggressive/early onset periodontitis, and many were not confident in treating advanced periodontitis (36.3 per cent) or aggressive periodontitis (51.6 per cent). The majority of dentists reported that they provided most of the non surgical periodontal therapy to their patients, while most surgical treatments were referred to specialist periodontists. Factors deemed to be important in influencing the decision to provide periodontal treatment included level of training and ability to motivate patients to improve oral hygiene. Many responents requested periodontic continuing education (CE) courses be run.

CONCLUSIONS

Most of the dentists surveyed were confident to diagnose periodontal disease and to treat the more common presentations of periodontal disease. There is some evidence to suggest that some practitioners are not following the minimum requirements set by the Dental Practice Board of Victoria in relation to periodontal record keeping. The results also indicate a need for more periodontic CE courses in Victoria.

Aggregation of human platelets by gingipain-R from Porphyromonas gingivalis cells and membrane vesicles

The hypothesis that there is an association between periodontitis and cardiovascular disease suggests new lines of research on the mechanism whereby oral bacteria might exert systemic effects. This study was conducted to ascertain and quantitate the effect of Porphyromonas gingivalis on human platelets in vitro. A second related objective was to purify and identify the aggregating vector. Aggregation was measured by platelet turbidometry and gingipain-R was purified from P. gingivalis membrane vesicles by Sepharose 2B and hydroxyapatite chromatography. The in vitro aggregation of platelets requires that at least 1.0 x 10(4) cells be stirred with 1.35 x 10(8) platelets. The specific activity is substantially increased in the membrane vesicles that are shed by this bacterium. Aggregability was due to gingipain-R activity, a potent cysteine protease that was found to be highly concentrated in the membrane vesicle fraction. The enzyme was purified 18-fold in high yield from the membrane vesicles, and consists of two noncovalently linked proteins that migrate at 49 and 44 kDa on SDS-PAGE. Aggregation of platelets by gingipain-R was shown to be dose-dependent, and inhibited by leupeptin and arginine, but not by anti-thrombin III. This is the first report enumerating the specific number of cells and lowest concentration of membrane vesicles necessary to evoke a full human platelet response, and the first report to assign this activity to gingipain-R.

Limited-dose Daclizumab versus Basiliximab: a comparison of cost and efficacy in preventing acute rejection

The purpose of this study was to compare the efficacy and cost of the limited-dose Daclizumab regimen to that of the standard-dose Basiliximab regimen. Two antibody induction regimens were compared in patients aged 18 years and older who received renal transplants from January 2002 to September 2003 and completed interleukin (IL)-2R antibody induction with standard-dose Basiliximab (20 mg x 2 doses) or limited-dose Daclizumab (1 mg/kg x 2 doses). The primary outcome measure was the incidence of acute rejection. Secondary outcomes included cost, changes in serum creatinine level, and delayed graft function. Of the 46 patients randomized, 42 patients completed the 6-month follow-up. Mean serum creatinine level at time of discharge was originally higher in the limited-dose Daclizumab group than the standard-dose Basiliximab group (1.89 vs 1.57, respectively). By 1, 3, and 6 months, mean serum creatinine values were similar between both groups, with a trend toward lower mean serum creatinine values in the limited-dose Daclizumab group. The incidence of acute rejection was also similar between the groups (6% vs 7%). The average cost difference between the 2 regimens was approximately $715. This study suggests that a limited-dose Daclizumab regimen may be an efficacious and less costly alternative to the standard-dose Basiliximab regimen for antibody induction therapy following renal transplantation.

The chimpanzee major histocompatibility complex class II DR subregion contains an unexpectedly high number of beta-chain genes

The major histocompatibility complex (MHC) class II DR subregion of the chimpanzee was studied by restriction fragment length polymorphism (RFLP) analysis. Genomic DNA obtained from a panel of 94 chimpanzees was digested with the restriction enzyme Taq I and hybridized with an HLA-DR beta probe specific for the 3' untranslated (UT) region. Such a screening revealed the existence of 14 distinct DRB/Taq I gene-associated fragments allowing the definition of 11 haplotypes. Segregation studies proved that the number of chimpanzee class II DRB/Taq I fragments is not constant and varies from three to six depending on the haplotype. Comparison of these data with a human reference panel manifested that some MHC DRB/Taq I fragments are shared by man and chimpanzee. Moreover, the number of HLA-DRB/Taq I gene-associated fragments detected in a panel of homozygous typing cells varies from one to three and corresponds with the number of HLA-DRB genes present for most haplotypes. However, a discrepancy is observed for the HLA-DR4, -DR7, and -DR9 haplotypes since a fourth HLA-DRB pseudogene present within these haplotypes lacks its 3' UT region and thus is not detected with the probe used. These results suggest that chimpanzees have a higher maximum number of DRB genes per haplotype than man. As a consequence, some chimpanzee haplotypes must show a dissimilar organization of the MHC DR subregion compared to their human equivalents. The implications of these findings are discussed in the context of the trans-species theory of MHC polymorphism.

A 22-bp fragment of the pea lectin promoter containing essential TGAC-like motifs confers seed-specific gene expression

To elucidate the molecular mechanisms responsible for seed-specific gene expression in plants, the promoter of the pea lectin (psl) gene, encoding an abundant seed protein, was used as a model. Leaf and seed nuclear proteins bound to a region in the psl promoter containing three overlapping TGAC-like motifs, which have been shown to be a binding site for basic/leucine zipper proteins, including TGA1a. A trimer of a 22-bp region of the psl promoter, containing the TGAC-like motifs, coupled to a heterologous minimal promoter conferred low reporter gene expression in root, stem, and leaf and high expression in seed of transgenic tobacco. Expression increased during the midmaturation stage of seed development and was observed in the endosperm as well as in the embryo, where it strongly decreased within a few days after germination. This expression pattern is qualitatively identical to the expression pattern conferred by a 2000-bp fragment of the psl promoter. Nucleotides within the TGAC-like motifs important for in vitro binding are also essential for in vivo transcription activation in vegetative tissue as well as in seed. The electrophoretic mobility of a DNA-protein complex containing seed nuclear protein was different from that formed with leaf nuclear protein. Furthermore, the TGA1a steady state mRNA level in immature seed was relatively low. These results suggest that a seed-specific factor different from TGA1a, but with similar binding specificity, is responsible for gene activation in seed. We conclude that the 22-bp region contains all the information, including an essential TGAGTCATCA sequence, necessary for seed-specific expression and very likely plays an essential role in the seed-specific expression pattern of the psl gene.

Subcutaneous epinephrine in the prehospital setting

OBJECTIVES

To outline current practice regarding the prehospital use of subcutaneous epinephrine, and systematically review the existing literature to determine the level of support for its use in the elderly. Many health care personnel are reluctant to administer subcutaneous epinephrine for potentially life-threatening conditions such as asthma and anaphylaxis in older patients. This sytematic review examined the following focused question: "For older patients not known to have coronary artery disease, does administration of subcutaneous epinephrine carry a significant enough risk of cardiovascular side effects to mandate age as a relative contraindication to self-administration or emergency medical services administration in the prehospital setting?"

METHODS

The MEDLINE and Health Star databases were searched to identify studies evaluating the use of subcutaneous epinephrine in the treatment of asthma and anaphylaxis. Bibliographies from included studies, known reviews, and textbooks were examined to identify additional studies. The strength of evidence presented in each study was assessed in accordance with the classification system proposed by the American Heart Association's Emergency Cardiovascular Care Committee.

RESULTS

The review of the literature revealed only three case reports (level VII evidence) that record adverse reactions of epinephrine when used for anaphylaxis and allergy, while several level III and V studies found no adverse effects when used for asthma. No controlled trials documenting adverse effects were found.

CONCLUSIONS

The authors did not find significant evidence to contraindicate the use of subcutaneous epinephrine in older patients who are not known to have coronary artery disease, who present with either asthma or allergic reactions.

Genetic variation in heat shock protein 70 is associated with septic shock: narrowing the association to a specific haplotype

Heat shock protein 70 (HSP70) plays a major role in immune responses. Polymorphisms within the gene have been associated with development of septic shock. This study refines the region of the HSP70 gene associated with development of septic shock and confirms its functionality. Subjects (n = 31) were grouped into one of three haplotypes based on their HSPA1B-179C>T and HSPA1B1267A>G genotypes. Mononuclear cells from these subjects were stimulated with heat-killed bacteria (10(7 )colony-forming units/mL Escherichia coli or Streptococcus pneumoniae) for 8 and 21 h. HSP70 and tumour necrosis factor (TNF) mRNA and protein levels were measured by reverse transcriptase-polymerase chain reaction and ELISA, respectively. The HSPA1B-179*C:1267*A haplotype was associated with significantly lower levels of HSPA1B mRNA and protein and higher production of TNF mRNA and protein compared to the other haplotypes. Induction of HSP70 was TNF independent. These results suggest that the HSPA1B-179C>T:1267A>G haplotype is functional and may explain the association of the HSP70 gene with development of septic shock.

RAP-1 is an Arabidopsis MYC-like R protein homologue, that binds to G-box sequence motifs

An Arabidopsis cDNA clone encoding a DNA-binding protein, RAP-1, was isolated by southwestern screening of an Escherichia coli cDNA expression library. The protein contains a bHLH DNA-binding domain and is homologous to R proteins, regulating anthocyanin biosynthesis. RAP-1 binds to the sequence CACNTG. It is encoded by a single gene, which is expressed to high levels in root and stem and to low levels in leaf and flower. No expression could be detected in siliques. Rap-1 does not correspond to one of the known loci involved in anthocyanin biosynthesis, since it is located at a different map position. In contrast to the maize R protein Lc, RAP-1 did not induce anthocyanin biosynthesis in pea cotyledons. Thus, RAP-1 is a novel member of the bHLH class of DNA-binding proteins.

Comprehensive development and testing of the ASIST-GBV, a screening tool for responding to gender-based violence among women in humanitarian settings

Background

Conflict affected refugees and internally displaced persons (IDPs) are at increased vulnerability to gender-based violence (GBV). Health, psychosocial, and protection services have been implemented in humanitarian settings, but GBV remains under-reported and available services under-utilized. To improve access to existing GBV services and facilitate reporting, the ASIST-GBV screening tool was developed and tested for use in humanitarian settings. This process was completed in four phases: 1) systematic literature review, 2) qualitative research that included individual interviews and focus groups with GBV survivors and service providers, respectively, 3) pilot testing of the developed screening tool, and 4) 3-month implementation testing of the screening tool. Research was conducted among female refugees, aged ≥15 years in Ethiopia, and female IDPs, aged ≥18 years in Colombia.

Results

The systematic review and meta-analysis identified a range of GBV experiences and estimated a 21.4 % prevalence of sexual violence (95 % CI:14.9-28.7) among conflict-affected populations. No existing screening tools for GBV in humanitarian settings were identified. Qualitative research with GBV survivors in Ethiopia and Colombia found multiple forms of GBV experienced by refugees and IDPs that occurred during conflict, in transit, and in displaced settings. Identified forms of violence were combined into seven key items on the screening tool: threats of violence, physical violence, forced sex, sexual exploitation, forced pregnancy, forced abortion, and early or forced marriage. Cognitive testing further refined the tool. Pilot testing in both sites demonstrated preliminary feasibility where 64.8 % of participants in Ethiopia and 44.9 % of participants in Colombia were identified with recent (last 12 months) cases of GBV. Implementation testing of the screening tool, conducted as a routine service in camp/district hospitals, allowed for identification of GBV cases and referrals to services. In this phase, 50.6 % of participants in Ethiopia and 63.4 % in Colombia screened positive for recent experiences of GBV. Psychometric testing demonstrated appropriate internal consistency of the tool (Cronbach’s α = 0.77) and item response theory demonstrated appropriate discrimination and difficulty of the tool.

Conclusion

The ASIST-GBV screening tool has demonstrated utility and validity for use in confidential identification and referral of refugees and IDPs who experience GBV.

Tissue-specific alterations in somatostatin mRNA accumulation in streptozocin-induced diabetes

In streptozocin-induced diabetes in rats, there is a marked increase in the content and release of immunoreactive somatostatin (SLI) from the pancreas and upper gut. To elucidate whether these SLI changes are associated with alterations in somatostatin gene transcription, we measured somatostatin mRNA (SmRNA) accumulation in these and other SLI-producing tissues. Pancreas, stomach, jejunum, hypothalamus, and cerebral cortex were removed from control rats, 6-wk-diabetic rats, and diabetic rats treated with insulin for 6 wk. Total RNA was isolated by centrifugation through CsCl and fractionated on agarose gels. A sensitive radiodensitometric hybridization assay was used to determine SmRNA levels in absolute amounts by in vitro synthesized sense-strand RNA as a quantitative standard and antisense cRNA as a specific probe. SLI was determined by radioimmunoassay. SmRNA exhibited size heterogeneity between the different control and diabetic tissues. A 2- to 3-fold increase in total SmRNA was found in pancreas and stomach of the diabetic rats that suppressed toward normal with insulin treatment. These two tissues also exhibited significant 1.6- to 2.6-fold increases in SLI, respectively. The remaining tissues showed no diabetes-related changes in SLI or SmRNA. We conclude that in insulinopenic diabetes, tissue SLI and SmRNA accumulation undergo parallel changes; are increased in pancreas and upper gut, reflecting augmented somatostatin synthesis; are reciprocally related to insulin acting directly or indirectly on somatostatin-producing cells; and are unchanged in the lower gut and brain, suggesting tissue-specific regulation of somatostatin gene transcription in diabetes.

Dentin ablation with three infrared lasers

BACKGROUND AND OBJECTIVE

Lasers are used for caries removal in enamel and dentin, but are currently limited in their ability to remove sound tooth structure. In this study plasma interaction regimes are investigated as the principal factor determining the ablation characteristics.

STUDY DESIGN/MATERIALS AND METHODS

Three ablation parameters are considered: ablation rates (AR), surface temperatures (ST), and surface morphological characteristics. The three lasers investigated were Er:YSGG with wavelength (WL) of 2.94 mu m and pulse duration (PD) of 250 mu s, Ho:YSGG at 2.1 mu m and 250 mu s and an Nd:YAG with WL of 1.06 mu M and PD of 15ns.

RESULTS

The highest surface temperatures were observed during Er:YSGG treatment (> 300 degrees C), moderate temperatures with the Ho:YSGG (150 degrees C), and lowest with the Nd:YAG (with highest surface temperature generally lower than 80 degrees C). Ablation rates were also compared and were shown to be highest with the Er:YSGG and Ho:YSGG, and lower with the Nd:YAG (< 3 mu m). In all systems, efficient ablation was observed only in the presence of plasma. In spite of their different wavelengths, for similar spot sizes, energy, and pulse duration, ablation rates of Ho:YSGG and Er:YSGG were found to be comparable. These were an order of magnitude larger than the ablation rates observed with the nanosecond system.

CONCLUSION

Possible explanation for these observations is given in terms of plasma characteristics.

Oral feeding of renal tubular antigen abrogates interstitial nephritis and renal failure in Brown Norway rats

We have examined whether oral feeding of antigen can regulate the expression of autoimmune interstitial nephritis induced by antigen-in-adjuvant (RTA/CFA) immunization of Brown Norway rats. Male rats were divided into six experimental groups: Group I, RTA/CFA immunization alone; Groups II, III, and IV were pretreated with 1 mg (Group II), 5 mg (Group III), and 25 mg (Group IV) of oral tubular antigen every other day for ten days, followed by RTA/CFA immunization; Group V was pretreated with a control antigen, followed by RTA/CFA immunization; and Group VI was immunized with CFA alone. Renal histology, inulin clearance, DTH responses to RTA, and IgG antibody responses to RTA were monitored as endpoints of the study. Our results demonstrated that Group III and IV animals had significantly less severe renal injury, as assessed by inulin clearance and extent of renal cortical involvement by mononuclear cells. Group II and IV animals had suppressed DTH responses, and only Group IV animals had significantly depressed antigen-specific IgG serum titers. Group III animals had neither suppressed DTH responses or IgG titers. We conclude that oral administration of tubular antigen can modulate the intensity of interstitial nephritis produced by immunization, but that the regulatory mechanism is not dependent (at all doses of fed antigen) on suppressed DTH reactivity to RTA or suppressed antigen-specific IgG.

Ovarian aging and hormone replacement therapy. Hormonal levels, symptoms, and attitudes of African-American and white women

OBJECTIVES

To characterize reproductive hormone levels, symptoms, and attitudes related to menopause among healthy, menstruating white and African-American women aged 44 to 49 years.

DESIGN

Pilot study; cross-sectional survey.

SETTING

Community-based convenience sample of women in the Philadelphia metropolitan area.

PARTICIPANTS

Thirty-three African-American and 35 white women.

MEASUREMENTS

The survey instrument collected demographic data, medical and reproductive history, health practices and behaviors. It included previously validated function, depression, and quality-of-life instruments, and a Menopause Attitude Scale that included two factors, attitudes toward the menopause and attitudes toward medical therapy. Anthropometric measurements were taken at enrollment, and reproductive hormones and daily symptom logs were followed over two menstrual cycles.

MAIN RESULTS

The two groups were comparable in mean age (African-American 46.2 years, white 46.9 years). Serum levels of estradiol, follicle-stimulating hormone, dihydroepiandrosterone-sulfate, and progesterone were comparable. Symptoms were similar in type and frequency. However, the African-American women had significantly more positive attitudes toward menopause, were more likely to rely on family for information about menopause, and were less likely to have been recommended hormone replacement therapy by their physicians. A majority of women in each group expressed satisfaction with the care they had received.

CONCLUSIONS

Perimenopausal African-American and white women have different expectations of menopause and the role of medical care in menopause. This bears directly on women's acceptance of hormone replacement therapy. Conclusions are limited by the small sample size and convenience nature of the study population: further work with larger samples is needed to confirm these apparent differences.