Vertical pathway inhibition of receptor tyrosine kinases and BAD with synergistic efficacy in triple negative breast cancer

Aberrant activation of the PI3K/AKT signaling axis along with the sustained phosphorylation of downstream BAD is associated with a poor outcome of TNBC. Herein, the phosphorylated to non-phosphorylated ratio of BAD, an effector of PI3K/AKT promoting cell survival, was observed to be correlated with worse clinicopathologic indicators of outcome, including higher grade, higher proliferative index and lymph node metastasis. The structural optimization of a previously reported inhibitor of BAD-Ser99 phosphorylation was therefore achieved to generate a small molecule inhibiting the phosphorylation of BAD at Ser99 with enhanced potency and improved oral bioavailability. The molecule 2-((4-(2,3-dichlorophenyl)piperazin-1-yl)(pyridin-3-yl)methyl) phenol (NCK) displayed no toxicity at supra-therapeutic doses and was therefore assessed for utility in TNBC. NCK promoted apoptosis and G0/G1 cell cycle arrest of TNBC cell lines in vitro, concordant with gene expression analyses, and reduced in vivo xenograft growth and metastatic burden, demonstrating efficacy as a single agent. Additionally, combinatorial oncology compound library screening demonstrated that NCK synergized with tyrosine kinase inhibitors (TKIs), specifically OSI-930 or Crizotinib in reducing cell viability and promoting apoptosis of TNBC cells. The synergistic effects of NCK and TKIs were also observed in vivo with complete regression of a percentage of TNBC cell line derived xenografts and prevention of metastatic spread. In patient-derived TNBC xenograft models, NCK prolonged survival times of host animals, and in combination with TKIs generated superior survival outcomes to single agent treatment. Hence, this study provides proof of concept to further develop rational and mechanistic based therapeutic strategies to ameliorate the outcome of TNBC.

The Impact of Preventive Dental Services on Subsequent Dental Treatment for Children in Medicaid

OBJECTIVE

The goal of this study was to use claims data linked with community-level measures to evaluate the impact of preventive services on the time to subsequent restorative, advanced restorative, and complex dental treatment among children enrolled in the Virginia Medicaid program.

METHODS

Four data sources were used (dental claims, eligibility files, American Community Survey, and Area Health Resource Files) for fiscal years 2011 to 2018. The outcomes of interest were time to first treatment services from birth. The treatment outcomes were basic restorative treatment, advanced restorative treatment, or complex treatment. The independent variable was a preventive service prior to a treatment service. Time-to-event curves were estimated and compared using a log-rank test. Propensity score-matched univariate and multivariate Cox proportional hazards frailty models with an inverse probability censoring weighting correction estimated hazard ratios (HRs) for treatment outcomes comparing use of preventive services while controlling for patient demographic, geospatial, and county-level socioeconomic status measures.

RESULTS

The analysis included 430,594 children (10,204,182 claims). A log-rank test showed significant differences (P < 0.001) between the times to treatment of those who had a preventive service and those who did not have a preventive service prior to a treatment service. Both Kaplan-Meier curves and the adjusted HR (1.88; 95% confidence interval [CI], 1.46-2.15) indicated that children without preventive services were more likely to have basic restorative treatment at an earlier age along with advanced restorative treatment (HR, 1.52; 95% CI, 1.28-1.80) and complex treatment (HR, 2.13; 95% CI, 1.68-2.61).

CONCLUSIONS

In a population of Medicaid-enrolled children, children who did not receive preventive services were significantly more likely to have treatment at an earlier age than those who did receive preventive services.

KNOWLEDGE TRANSFER STATEMENT

This study examines the impact of the utilization of preventive dental services since birth and the subsequent dental treatment for children enrolled in a dental Medicaid program. This study also examines the influence of preventive care on dental complexity of treatment for these children. Findings can inform federal and state policy planning of dental Medicaid programs as well as interventions to improve referral systems for the early use of preventive dental services and the establishment of a dental home.

Effect of mobile voice calls on treatment initiation among patients diagnosed with tuberculosis in a tertiary care hospital of Puducherry: A randomized controlled trial

Objective

In India, about one third of tuberculosis (TB) patients diagnosed at tertiary hospitals are missed during a referral to peripheral health institutes for treatment. To address this, we assessed whether mobile voice call reminders to TB patients after diagnosis at a tertiary hospital decrease the proportion of "pretreatment loss to follow-up" (PTLFU), compared with the conventional paper-based referral.

Design

A two-group parallel-arm randomized controlled trial was conducted.

Setting

The study was conducted in a tertiary care hospital at Puducherry, South India.

Participants

All newly diagnosed TB patients, both pulmonary and extrapulmonary, who were referred for treatment from the selected tertiary care hospital and possessed a mobile phone were eligible to participate. The participants were enrolled between March 2015 and June 2016 and were randomized to study groups using the block randomization with allocation concealment.

Intervention

The participants in the intervention arm received standardized mobile voice calls reminding them to register for anti-TB treatment on the second and seventh day after referral in addition to the conventional paper-based referral received by the control group.

Primary outcomes

Patients not started on anti-TB treatment within 14 days of referral were considered as PTLFU. The outcome of PTLFU was ascertained through phone calls made on the 14^th day after referral. The intention-to-treat analysis was used, and the proportion of PTLFU in the study groups and the risk difference with 95% confidence interval (CI) were calculated.

Results

Of the 393 patients assessed for eligibility, 310 were randomized to the intervention (n = 155) and control (n = 155) arms. In the intervention arm, 14 (9%) out of 155 were PTLFU compared with 28 (18%) of the 155 patients in the control arm. The absolute risk difference was 9% (95% CI [1.5, 16.6], P = 0.01).

Conclusion

Mobile voice call reminder to patients is a feasible intervention and can reduce PTLFU among referred TB patients.

Isoniazid preventive treatment in children in two districts of South India: does practice follow policy?

SETTING

Two districts of Tamil Nadu, India

OBJECTIVES

To determine the proportion of household contacts aged <6 years of patients with tuberculosis (TB) with positive sputum microscopy results who initiated and completed isoniazid preventive treatment (IPT), and to determine reasons for non-initiation and non-completion of IPT.

DESIGN

Household visits were conducted on a random sample of adult patients registered during January-June 2012 to identify household contacts aged <6 years.

RESULTS

Among 271 children living with 691 index patients, 218 (80%) were evaluated and 9 (4%) were diagnosed with TB. Of 209 remaining contacts, 70 (33%) started IPT and 16 (22.9%) completed a full course of IPT. Of 139 contacts who did not start IPT, five developed TB disease. Reasons for non-initiation of IPT included no home visit by the field staff (19%) and no education about IPT (61%). Reasons for non-completion included isoniazid not provided (52%) and long duration of treatment (28%).

CONCLUSION

This study shows that Revised National TB Programme guidance was not being followed and IPT implementation was poor. Poor IPT uptake represents a missed opportunity to prevent future TB cases. Provision of IPT may be improved through training, improved logistics and enhanced supervision and monitoring.

HIV Clade-C Infection and Cognitive Impairment, Fatigue, Depression, and Quality of Life in Early-Stage Infection in Northern Indians

HIV disease progression is associated with declining quality of life and overall health status, although most research in this domain has been conducted among Western populations where B is the infecting clade. This study sought to determine the effects of early-stage clade-C HIV infection (CD4 count ≥400 cells/mm(3)) on neurocognitive functioning, cognitive depression, and fatigue by comparing a matched sample of HIV-positive and HIV-negative Northern Indians. This study also examined the impact of these factors on quality of life within the HIV-positive individuals. HIV-positive participants demonstrated reduced cognitive functioning, increased fatigue, and lower quality of life. Fatigue and cognitive impairment interacted to negatively impact quality of life. Results suggest that early-stage HIV clade-C-infected individuals may experience subclinical symptoms, and further research is needed to explore the benefit of therapeutic interventions to ensure optimal clinical outcomes and maintain quality of life in this vulnerable population.

Haplotypes of the cholesteryl ester transfer protein gene predict lipid-modifying response to statin therapy

Cholesteryl ester transfer protein (CETP) plays a central role in high-density lipoprotein (HDL) metabolism. Single nucleotide polymorphisms (SNPs) and haplotypes in the CETP gene were determined in 98 patients with untreated dyslipidemias and analyzed for associations with plasma CETP and plasma lipids before and during statin treatment. Individual CETP SNPs and haplotypes were both significantly associated with CETP enzyme mass and activity. However, only certain CETP haplotypes, but not individual SNPs, significantly predicted the magnitude of change in HDL cholesterol (HDL-C) and triglycerides. After adjusting for covariates and multiple testing, the TTCAAA haplotype showed a gene-dose effect in predicting the HDL-C increase (P=0.03), while the TTCAAAGGG and AAAGGG haplotypes predicted a decrease in triglycerides (P=0.04 both). This is the first study to demonstrate that SNP haplotypes derived from allelic SNP combinations in the CETP gene were more informative than single SNPs in predicting the response to lipid-modifying therapy with statins.

Ventilation/perfusion scintigraphy

V/Q imaging is often very useful in evaluating patients in whom a PE is suspected. A normal scan result can be used to exclude embolism and a high likelihood ratio scan can be used to make the diagnosis of PE. Most patients with PE do not have high likelihood ratio scans; therefore, it is important to pursue this diagnosis in patients with intermediate likelihood ratio scans and in the appropriate clinical setting for patients with the low likelihood ratio scans. In patients with parenchymal chest x-ray abnormalities who are likely to fall into the intermediate category, it can be more appropriate to use CT angiography instead of V/Q scintigraphy. This strategy probably increases the fraction of scans with high diagnostic utility.

Cerebrospinal fluid 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in HIV-1 infection

Reduced level of serotonin (5-hydroxytryptamine, 5-HT) in humans has been associated with a number of mental health and behavioral problems including depression, aggression, violence, sexual dysfunctions, sleep and eating disorders. Even though among HIV-1-infected individuals, prevalence of mental health and behavioral problems are common, their relationship with central nervous system serotonin functions is not clearly understood. This investigation was carried out to study the status of CSF 5-HT in HIV-1+ subjects (n = 21), in the early stage of infection, and HIV-1- control subjects (n = 24). Samples of CSF were obtained by lumbar puncture and were analyzed for 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA), using high-performance liquid chromatography equipped with electrochemical detector. Levels of CSF 5-HT were significantly lower in the HIV-1+ group compared to the HIV-1- group. There was no significant difference in the CSF 5-HIAA levels between the two groups. In both groups, however, there was a significant correlation between CSF 5-HT and 5-HIAA. In the HIV-1 + group, although CSF 5-HT level was significantly negatively correlated with serostatus, there was no correlation between either CSF 5-HT or 5-HIAA levels and CD4 cell number or any behavioral measures evaluated in this study, including Beck's Depression Inventory and state/trait anxiety scores. These data suggest that HIV-1 infection affects the CNS 5-HT status with no significant association with measures of depression and anxiety, at least in the early stage of infection.

Haplotype variation and linkage disequilibrium in 313 human genes

Variation within genes has important implications for all biological traits. We identified 3899 single nucleotide polymorphisms (SNPs) that were present within 313 genes from 82 unrelated individuals of diverse ancestry, and we organized the SNPs into 4304 different haplotypes. Each gene had several variable SNPs and haplotypes that were present in all populations, as well as a number that were population-specific. Pairs of SNPs exhibited variability in the degree of linkage disequilibrium that was a function of their location within a gene, distance from each other, population distribution, and population frequency. Haplotypes generally had more information content (heterozygosity) than did individual SNPs. Our analysis of the pattern of variation strongly supports the recent expansion of the human population.

Regulation of HEMA1 expression by phytochrome and a plastid signal during de-etiolation in Arabidopsis thaliana

The synthesis of 5-aminolevulinic acid (ALA) is the rate-limiting step for the formation of all plant tetrapyrroles, including chlorophyll and heme, and regulation of ALA synthesis is therefore critical to plant development. Glutamyl-tRNA reductase (GluTR) is the first committed enzyme of this pathway and is encoded by a small family of nuclear HEMA genes. Here, we have used transgenic Arabidopsis (Arabidopsis thaliana L. Col) lines expressing chimeric HEMA1 promoter:gusA fusion genes, combined with RNA gel blot analyses, to characterise the light-mediated regulation of the Arabidopsis HEMA1 gene during de-etiolation. HEMA1 was expressed strongly, but not exclusively, in photosynthetic tissues and was shown to be light regulated at the transcriptional level by the phytochrome family of photoreceptors acting in both the far-red high irradiance and low fluence response modes. The HEMA2 gene, which is expressed only in roots of seedlings, was not light regulated. Analysis of truncated HEMA1 promoter constructs demonstrated that a -199/+252 promoter fragment was sufficient to confer full light-responsiveness to gusA expression. This fragment contained GT-1/I-box and CCA-1 binding sites that are implicated as the light-responsive cis elements. Both the full-length and truncated HEMA1 promoters required the presence of intact chloroplasts for full expression, consistent with previous indications that light and plastid factor signals converge to co-ordinately regulate expression of photosynthesis-related nuclear genes. These results provide the most comprehensive analysis to date of the light-regulation of a tetrapyrrole biosynthetic gene and support a direct link between regulation of HEMA1 transcription and chlorophyll accumulation during seedling de-etiolation.

Client donation program for acquiring dogs and cats to teach veterinary gross anatomy

A donor program for procuring dogs and cats to meet the needs of anatomical instruction was initiated six years ago at Tufts University School of Veterinary Medicine. The program was initiated in order to comply with state regulations that preclude the use of shelter animals and to satisfy ethical objections of students and faculty. The donor program has successfully met the animal needs for teaching gross anatomy and, in addition, provides opportunities to integrate clinical perspectives and ethics beginning from the first year of veterinary education.

Peripheral serotonin levels in women: role of aging and ethnicity

Serotonin has been implicated to play an important role in regulating emotions and behavior, and it is well accepted that the platelet serotonergic system mirrors the presynaptic central serotonergic system. Since prevalence of psychiatric problems increases with age and women are known to be more vulnerable than men, the present investigation was carried out to study the relationship between serotonin activity and age in women. Levels of serotonin (5-hydroxytryptamine, 5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) were measured in platelets and plasma in women (n = 49) aged 40-84 years (30 women aged 40-60 years and 19 women aged 61-84 years). There was a significant age difference between the two groups (mean: 47.6 +/- 5.91 years in the younger and 73.0 +/- 6.83 years in the older women, respectively, p < 0.00001). Platelet 5-HT as well as 5-HIAA levels were significantly higher in older women as compared to those in the younger women (89.41 +/- 21.95 ng/10(8) platelets in younger vs. 112.9 +/- 36.07 in older women, p < 0.02, and 1.20 +/- 1.10 in younger vs. 2.19 +/- 1.88 ng/10(8) platelets in older women, p < 0.05, respectively). Pearson correlation coefficients determined in the combined group (n = 49) showed a significant positive correlation between platelet 5-HT and age (r = 0.31, p < 0.03). Plasma 5-HT levels on the other hand were lower in older women compared to those in the younger women (4.50 +/- 3.20 in younger vs. 1.04 +/- 1.28 ng/ml plasma in older women, p < 0.0001) and a significant negative correlation was observed between plasma 5-HT and age (r = -0.44, p < 0.002). Plasma 5-HIAA concentration did not differ between the two groups. Platelet 5-HT levels in the younger group were independent of ethnicity. Since high serotonin activity has also been associated with psychiatric problems, our results of increased concentration of platelet 5-HT as well as 5-HIAA with age may have implications in predisposing aging women to behavioral/psychiatric problems.

Neogenesis of pancreatic endocrine cells in copper-deprived rat models

Transplantation of progenitor cells for regeneration of islet cells could prove invaluable in the treatment of diabetes mellitus. This study provides evidence that in rats maintained on a copper-deficient diet containing the copper-chelating agent tetraethylenepentamine pentahydrochloride, regeneration of single alpha and beta endocrine cells in the ductules and acinar tissue of the adult rat pancreata occurred. These regenerated cells both in the ductules and acinar tissue stained positive for glucagon and insulin similar to cells within the islets and in addition to being reactive to proliferative cellular nuclear antigen, an intracellular marker of active proliferation. In contrast, the control group pancreata did not show any evidence of islet regeneration, proliferation, or proliferative cellular nuclear antigen reactivity pre- or posttransplantation. Transplantation of digested pancreatic tissues from the copper-deficient group into the spleen of syngeneic diabetic rats reversed diabetes, and this was confirmed histologically by demonstrating cells within ductules that stained positively for insulin. This study concludes that copper deprivation contributes to the neogenesis of pancreatic alpha and beta cells in the ductules and acinar tissue of adult pancreas in rat model and that transplanted stem cells maintain their functional capacity in the recipient after transplantation.

Nefazodone treatment of adolescent depression: an open-label study of response and biochemistry

OBJECTIVE

The purpose of this study was to find whether nefazodone, effective in adult depression, might be similarly improve symptoms of adolescent depression. Secondary purpose was to relate platelet serotonin content to response, and to find if nefazodone's effect on platelet content was similar to that of the SSRIs.

METHOD

10 adolescents meeting DSMIV criteria for major depression received up to 400 mg of nefazodone for an eight week period. Response was assessed at baseline, 1, 2, 4, and 8 weeks by BDI and HDRS; platelet serotonin (5HT) content was obtained at baseline and final visit (for two dropouts, this was done at last visit, i.e., week 4).

RESULTS

In LOCF analysis, significant improvement was found in both HDRS (20.9 to 8.9, p = .01) and BDI (24.6 to 10.2, p = .01). Eight of nine patients with available data showed increases in platelet 5HT content (.02). In seven patients of eight completers with available data, there was a nonsignificant trend for patients with platelet 5HT baseline greater than 30 ng/10(8) platelets to show a greater change in HDRS than those with a baseline of less than 30 ng/10(8) platelets (p = .07).

CONCLUSIONS

Further double-blind study of nefazodone in adolescent depression is indicated; nefazodone appears to increase platelet 5HT content.

Antisense HEMA1 RNA expression inhibits heme and chlorophyll biosynthesis in arabidopsis

5-aminolevulinic acid (ALA) is a precursor in the biosynthesis of tetrapyrroles including chlorophylls and heme. The formation of ALA involves two enzymatic steps which take place in the chloroplast in plants. The first enzyme, glutamyl-tRNA reductase, and the second enzyme, glutamate-1-semialdehyde-2,1-aminomutase, are encoded by the nuclear HEMA and GSA genes, respectively. To assess the significance of the HEMA gene for chlorophyll and heme synthesis, transgenic Arabidopsis plants that expressed antisense HEMA1 mRNA from the constitutive cauliflower mosaic virus 35S promoter were generated. These plants exhibited varying degrees of chlorophyll deficiency, ranging from patchy yellow to total yellow. Analysis indicated that these plants had decreased levels of chlorophyll, non-covalently bound hemes, and ALA; their levels were proportional to the level of glutamyl-tRNA reductase expression and were inversely related to the levels of antisense HEMA transcripts. Plants that lacked chlorophyll failed to survive under normal growth conditions, indicating that HEMA gene expression is essential for growth.

Music therapy increases serum melatonin levels in patients with Alzheimer's disease

CONTEXT

Music therapy is known to have healing and relaxing effects. Although these effects appear to be mediated by release of neurotransmitters and neurohormones, the specific neurohormonal systems involved have not been fully investigated.

OBJECTIVE

To assess the effects of a music therapy intervention on concentrations of melatonin, norepinephrine, epinephrine, serotonin, and prolactin in the blood of a group of patients with Alzheimer's disease.

DESIGN

Blood samples were obtained before initiating the therapy, immediately at the end of 4 weeks of music therapy sessions, and at 6 weeks follow-up after cessation of the sessions.

SETTING

Miami Veterans Administration Medical Center, Miami, Fla.

PATIENTS

20 male inpatients with Alzheimer's disease.

INTERVENTION

30- to 40-minute morning sessions of music therapy 5 times per week for 4 weeks.

MAIN OUTCOME MEASURES

Changes in melatonin, norepinephrine, epinephrine, serotonin, and prolactin following music therapy.

RESULTS

Melatonin concentration in serum increased significantly after music therapy and was found to increase further at 6 weeks follow-up. A significant increase was found between baseline values and data recorded after the music therapy sessions as well as at 6 weeks follow-up. Norepinephrine and epinephrine levels increased significantly after 4 weeks of music therapy, but returned to pretherapy levels at 6 weeks follow-up. Serum concentration of prolactin and platelet serotonin levels remained unchanged after 4 weeks of music therapy and at 6 weeks follow-up.

CONCLUSION

Increased levels of melatonin following music therapy may have contributed to patients' relaxed and calm mood.

Differential expression and selective localization of vascular permeability factor/vascular endothelial growth factor in the rat uterus during the estrous cycle

This study examines the expression of the multi-functional cytokine, vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) in the rat uterus during early proestrus, proestrus, estrus and diestrus. Groups of ovariectomized or hypophysectomized rats served as endocrine controls. Expression of VPF/VEGF mRNA was 2-fold greater in uteri during proestrus and estrus than in other phases of the estrous cycle. In situ hybridization techniques indicated that VPF/VEGF mRNA expression was confined to the luminal epithelium during proestrus, but shifted to the stromal compartment during estrus. Ovariectomized, hypophysectomized or diestrus rats exhibited scattered localization of VPF/VEGF mRNA among glandular epithelium and endometrial stromal compartments. Although VPF/VEGF mRNA was expressed throughout the estrous cycle, but in different compartments of the endometrium depending on the stage of the estrous cycle, VPF/VEGF protein expression appears to be restricted to the epithelial compartment during proestrus and estrus. Results indicate that circulating levels of gonadal steroids and LH may be associated with the differential expression of VPF/VEGF mRNA and its translation activity in the endometrium during different stages of the estrous cycle.

Cocaine abuse and HIV-1 infection: epidemiology and neuropathogenesis

The epidemiology of cocaine abuse and potential relationships of cocaine withdrawal to human immunodeficiency virus type 1 (HIV-1)-associated dementia (HAD) are discussed. Neuroendocrinological changes in HIV-1 infection of the central nervous system (CNS) are discussed with the relevant impact of cocaine abuse. HIV-1 load in the brain tissue of infected substance users is described along with possible associations with neuropathology and HAD. Finally, the molecular epidemiology and sequence heterogeneity of HIV-1 and their implications for neuropathogenesis are summarized. The complex context of addressing cocaine abuse in the setting of HIV-1 infection appears more tractable when decomposed into its components.

Long-term function and survival of elderly donor kidneys transplanted into young adults

BACKGROUND

Traditionally, elderly donor kidneys have not been widely accepted for transplantation on the assumption of inferior performance. However, the United Network for Organ Sharing reports an increase in the number of elderly donors from less than 2% in 1982 to 24% in 1995. This trend is commensurate with the increase of older dialysis patients and an overall increase in the elderly population in the United States (1). Optimal utilization of these kidneys is essential to overcome the acute organ shortage.

METHODS

In this study, we transplanted 25 kidneys from elderly donors (ages 56-72 years) into young adult recipients (ages 20-50 years) (group 1) over a 4-year period. We compared the results with matched recipients of young adult donor kidneys (group 2) with regard to long-term kidney function and graft survival. A pretransplant biopsy of elderly donor kidneys was carried out and a frozen section report was obtained. Only those kidneys showing glomerulosclerosis of less than 20% were accepted for transplantation. All cadaveric kidneys were preserved in University of Wisconsin solution.

RESULTS

Pretransplant biopsies of elderly donor kidneys showed structural deficits, which included glomerulosclerosis in 85%, arteriolar and/or mesangial thickening in 75%, and interstitial lymphocyte infiltration in 30%. The mean serum creatinine was 2.4+/-0.74, 2.2+/-0.56, and 2.9+/-0.76 mg/100 ml in group 1 and 1.5+/-0.55, 2.3+/-2.24, and 1.7+/-0.62 in group 2 at 1, 3, and 5 years, respectively. The patient survival was 92%, 92%, and 88% in group 1, and 100%, 100%, and 100% in group 2 at 1, 3, and 5 years, respectively. The graft survival was 80%, 64%, and 56% in group 1 and 100%, 96%, and 88% in group 2 at similar time intervals. The differences in the serum creatinine and graft survival between the two groups were statistically significant (P < 0.05).

CONCLUSIONS

Most of the elderly donor kidneys with structural deficits transplanted into young adults provided suboptimal function and inferior long-term graft survival. To maximize the utilization and optimize the survival of elderly donor kidneys, we propose transplantation of these kidneys into age-matched recipients with similar physiological requirements as those of donors, with regard to kidney function.

The effect of selected classical music and spontaneous imagery on plasma beta-endorphin

This study explored the effect of music and imagery on plasma beta-endorphin in 78 undergraduates. Subjects screened for relevant psychological and health criteria were assigned to music imaging, silent imaging, music listening, and control conditions. Subjects donated 15 ml of blood prior to and following the 2-hr intervention period. There were no group differences in potential confounding variables. Split-plot factorial analysis controlling for individual differences in pretest level of beta-endorphin revealed that those in the music imaging group experienced a significant pre-post decline in beta-endorphin, while no other group demonstrated any significant pre-post difference. These data suggest that music imaging may lower peripheral beta-endorphin levels in healthy subjects. Further exploration of the effects of music and imagery interventions on physiology and health may be warranted.

Lack of change in fluoxetine and norfluoxetine kinetics when switching from fluoxetine to paroxetine

Pharmacokinetic interactions are possible with the prescription of two or more psychotropics. This caution could also apply to the proximal use of selective serotonin (5-hydroxytryptamine) reuptake inhibitors (SSRIs), especially those that may be potent inhibitors of specific hepatic metabolizing enzyme systems. Both fluoxetine (FLX) and paroxetine (PAR) are inhibitors of the cytochrome P4502D6 enzyme system. In order to assess the potential pharmacokinetic interactions between these two SSRIs, nine patients were first treated with fixed therapeutic doses of FLX for a minimum of 6 weeks. Subsequently, in a double-blind design, some of these patients were abruptly switched to PAR, 20 mg/day, and others were switched to placebo. Serum levels of FLX, norfluoxetine (NFLX), and PAR were collected before and at specific points after the switch. The results suggest that the clearance kinetics of FLX and NFLX are not affected by the abrupt switch to PAR. It was not possible to determine whether the kinetics of PAR were influenced by the residual FLX and NFLX concentrations.

A second and differentially expressed glutamyl-tRNA reductase gene from Arabidopsis thaliana

5-Aminolevulinic acid (ALA) is the universal precursor of tetrapyrroles (e.g., chlorophylls and hemes). In the chloroplasts of plants and in several eubacterial species ALA is formed in a two-step process known as the C5 pathway. In the first step, glutamyl-tRNA reductase (GluTR), converts glutamate of glutamyl-tRNA to glutamate 1-semialdehyde (GSA) which is rearranged to ALA by glutamate 1-semialdehyde-2,1-aminomutase (GSA-A) in the second step. Since ALA formation is a limiting step in chlorophyll biosynthesis, GluTR, which is encoded by the HEMA gene in Arabidopsis thaliana plays a vital role in that biosynthesis. Here we report the occurrence of a second functional HEMA gene (HEMA2) in A. thaliana. This gene was isolated by screening a genomic library with a probe from HEMA1. The nucleotide sequence of the cDNA and the corresponding genomic DNA indicates that the Arabidopsis HEMA2 gene contains two short introns (285 bp and 159 bp). The deduced amino acid sequence predicts a HEMA2 protein of 530 amino acids with 79% identity to the HEMA1-encoded GluTR. The 5'-flanking sequence of the HEMA2 gene includes several motifs (e.g., GT-1 boxes, GATA motifs) similar to light-responsive regulatory elements found in light-inducible genes. Unlike the HEMA1 transcript, which is present in all parts of the plant, HEMA2 is expressed in low levels in roots and flowers. The presence of a second functional HEMA gene in Arabidopsis raises the possibility that two C5 pathways exist in chloroplasts.

Serotonin uptake and its kinetics in platelets of women with Alzheimer's disease

The uptake of serotonin (14C-5-hydroxytryptamine, 5HT) in platelets and its kinetic characteristics were investigated in a group of women (n = 20) with probable Alzheimer's Disease (mean age = 76.0, years, SD = 8.27, range = 63-88) and in healthy normal women (n = 18, mean age = 72.6 years, SD = 7.24, range = 61-84). Both the apparent affinity of binding of 5HT to the platelet membrane (Km) and the maximum velocity (Vmax) of the rate of transport of 14C-5HT into platelets were significantly higher in the Alzheimer's Disease group than in the normal comparison group. Initial velocity of 14C-5HT uptake not passive diffusion (nonspecific uptake of 14C-5HT at 4 degrees C) differed significantly in the two groups. Our findings suggest abnormalities in the kinetic mechanisms involved in the uptake of 14C-5HT by platelets in women with Alzheimer's Disease.

Peripheral serotonin in Alzheimer's disease

The platelet has been suggested to be a peripheral model of the central serotonergic neuron. This investigation was carried out in order to test the hypothesis that levels of serotonin (5-HT) in the platelet will be decreased in Alzheimer's disease (AD) since neurochemical studies suggest that levels of 5-HT are decreased in the brain of AD patients. We investigated platelet and plasma 5-HT in a group of AD patients (n = 22) as well as in age-matched normal control subjects (n = 20). The results show that the platelet level of 5-HT was significantly reduced in AD (65.7 +/- 28.41 ng/10(8) platelets in AD vs. 112.9 +/- 35.11 ng/10(8) platelets in controls; p = 0.0001). There was no effect on the levels of its metabolite 5-hydroxyindoleacetic acid. These findings suggest that the peripheral serotonergic system in AD is adversely affected.

Rapid purification of tRNA(Lys) from rat liver

Fast protein liquid chromatography (FPLC) system using Mono Q (HR 5/5) anion-exchange column chromatography followed by highly cross-linked urea-polyacrylamide gel electrophoresis (urea-PAGE) was used for the purification of lysine-specific tRNA (tRNA(Lys)) from rat liver. Crude tRNA from rat liver was fractionated with a linear gradient of NaCl (0.3-0.8 M) in triethanolamine-HCl buffer, pH 4.5, and the activity of tRNA(Lys) was found to elute between 0.51 and 0.57 M NaCl. Using this concentration range of NaCl, tRNA(Lys) was refractionated on the same column with a shallow gradient, where a single peak of tRNA(Lys) activity was obtained. tRNA(Lys)-rich fractions recovered from the second run were electrophoretically separated on 16% polyacrylamide-7 M urea gel into one major band and three minor bands. The major band showed a specific activity of 997 pmols/A260 U for tRNALys with a 43-fold purification and approximately 17% recovery. The minor bands displayed negligible or no activity for lysine. tRNA(Lys) obtained by this method was found to be homogeneous by competitive aminoacylation. The advantages of FPLC followed by urea-PAGE in the purification of an amino acid-specific tRNA over conventional column chromatography are discussed.

Light regulation of chlorophyll biosynthesis at the level of 5-aminolevulinate formation in Arabidopsis

5-Aminolevulinic acid (ALA) is the universal precursor of tetrapyrroles, such as chlorophyll and heme. The major control of chlorophyll biosynthesis is at the step of ALA formation. In the chloroplasts of plants, as in Escherichia coli, ALA is derived from the glutamate of Glu-tRNA via the two-step C5 pathway. The first enzyme, Glu-tRNA reductase, catalyzes the reduction of Glu-tRNA to glutamate 1-semialdehyde with the release of intact tRNA. The second enzyme, glutamate 1-semialdehyde 2,1-aminomutase, converts glutamate 1-semialdehyde to ALA. To further examine ALA formation in plants, we isolated Arabidopsis genes that encode the enzymes of the C5 pathway via functional complementation of mutations in the corresponding genes of E. coli. The Glu-tRNA reductase gene was designated HEMA and the glutamate 1-semialdehyde 2,1-aminomutase gene, GSA1. Each gene contains two short introns (149 and 241 nucleotides for HEMA, 153 and 86 nucleotides for GSA1). The deduced amino acid sequence of the HEMA protein predicts a protein of 60 kD with substantial similarity (30 to 47% identity) to sequences derived from the known hemA genes from microorganisms that make ALA by the C5 pathway. Purified Arabidopsis HEMA protein has Glu-tRNA reductase activity. The GSA1 gene encodes a 50-kD protein whose deduced amino acid sequence shows extensive homology (55 to 78% identity) with glutamate 1-semialdehyde 2,1-aminomutase proteins from other species. RNA gel blot analyses indicated that transcripts for both genes are found in root, leaf, stem, and flower tissues and that their levels are dramatically elevated by light. Thus, light may regulate ALA, and hence chlorophyll formation, by exerting coordinated transcriptional control over both enzymes of the C5 pathway.

Effect of chronic DDC treatment on LHRH and substance P amidation processes in the rat

We examined the effects of chronic diethyldithiocarbamate (DDC) treatment on the concentrations of methionine-enkephalin, mature and unamidated forms (-Gly) of luteinizing hormone releasing hormone (LHRH) and substance P (SP) in various regions of the central nervous system (CNS). Chronic DDC treatment resulted in elevations of LHRH-Gly like immunoreactivity in the preoptic area (POA) and the medial basal hypothalamus (MBH), as well as elevations in SP-Gly like immunoreactivity in all areas of the CNS examined. Castration altered the ratios of SP-G-like/SP-like immunoreactivity in the pons, and LHRH-Gly like immunoreactivity in the MBH. Met-enkephalin concentrations were significantly elevated in the pons and medulla of intact DDC-treated animals, and in the POA of both intact- and castrated DDC-treated animals. Results demonstrate that it is possible to detect basal levels of unamidated LHRH and SP in many areas of the CNS, with ratios of unamidated/amidated peptides representing a unique and sensitive method for determining altered posttranslational processing of these transmitters, especially under altered endocrine states such as castration. Pharmacological blockade of terminal enzymatic processing of these peptides may be useful in studying upstream regulatory events in peptidergic neurons.

Influence of halothane and methoxyflurane on regional brain and spinal cord concentrations of methionine-enkephalin in the rat

Rats were exposed to either oxygen (controls), 1.5% halothane in oxygen, or methoxyflurane (0.5%) in oxygen over a period of 2 h, then sacrificed at the end of exposure (2-h group), 4 h after removal from environmental chamber (4-h group), or at 24 h following anesthetic exposure (24-h group). Pituitary (excluding the neural lobe, Pit), brain, and spinal cord areas were isolated and processed with Met-enkephalin tissue concentrations determined. In halothane-exposed animals, Met-enkephalin concentrations in pit and across CNS areas studied were significantly lower at 2 h following anesthetic exposure than in control animals. Concentrations of Met-enkephalin in many areas of CNS and Pit of 4-h group approached control levels. Concentrations of Met-enkephalin in all areas studied except spinal cord returned to basal levels by 24 h following halothane exposure. Exposure to methoxyflurane resulted in less dramatic changes in Met-enkephalin concentrations across CNS regions examined. Exposure to methoxyflurane resulted in significant decreases in Met-enkephalin levels in olfactory bulb, thalamus, and hippocampus only. Met-Enkephalin levels did not change significantly in other areas of the central nervous system following methoxyflurane exposure. These results indicate that halothane and methoxyflurane may have differential effects on the endogenous opioid system.

Abnormal pituitary-adrenocortical response in early HIV-1 infection

The corticotropin-adrenocortical response to cold pressor challenge was investigated in a study of human immunodeficiency virus (HIV) infection. Data obtained from 16 HIV-1-positive and 28 HIV-1-negative subjects are presented in this report. After the insertion of a venicatheter and following 30 min of rest, the subjects immersed one of their hands in an ice-water mixture for 2 min, and serial blood samples were obtained for the determination of ACTH and cortisol levels. The results show a significant blunting in the ACTH response and marginally lower levels of cortisol, over all time points, in HIV-1-positive subjects compared to that in HIV-1-negative subjects.

Arabidopsis alternative oxidase sustains Escherichia coli respiration

Glutamyl-tRNA reductase, encoded by the hemA gene, is the first enzyme in porphyrin biosynthesis in many organisms. Hemes, important porphyrin derivatives, are essential components of redox enzymes, such as cytochromes. Thus a hemA Escherichia coli strain (SASX41B) is deficient in cytochrome-mediated aerobic respiration. Upon complementation of this strain with an Arabidopsis thaliana cDNA library, we isolated a clone which permitted the SASX41B strain to grow aerobically. The clone encodes the gene for Arabidopsis alternative oxidase, whose deduced amino acid sequence was found to have 71% identity with that of the enzyme from the voodoo lily, Sauromatum guttatum. The Arabidopsis protein is expressed as a 31-kDa protein in E. coli and confers on this organism cyanide-resistant growth, which in turn is sensitive to salicylhydroxamate. This implies that a single polypeptide is sufficient for alternative oxidase activity. Based on these observations we propose that a cyanide-insensitive respiratory pathway operates in the transformed E. coli hemA strain. Introduction of this pathway now opens the way to genetic/molecular biological investigations of alternative oxidase and its cofactor.

Glutamyl-tRNA reductase from Escherichia coli and Synechocystis 6803. Gene structure and expression

In the cyanobacterium Synechocystis sp. PCC 6803 and in the enterobacterium Escherichia coli delta-amino-levulinic acid (ALA) is formed from glutamyl-tRNA by the sequential action of two enzymes, glutamyl-tRNA reductase (GluTR) and glutamate-1-semialdehyde aminotransferase. E. coli has two GluTR proteins with sizes of 45 kDa (GluTR45) and 85 kDa (GluTR85) (Jahn, D., Michelsen, U., and Söll, D. (1991) J. Biol. Chem. 266, 2542-2548). The hemA gene, isolated from E. coli and several other eubacteria, has been proposed to encode a structural component of GluTR. Because of the inability to overexpress this gene in E. coli, we demonstrate directly GluTR function for the E. coli hemA gene product by its expression and functional analysis in yeast, which does not form ALA from Glu-tRNA. Gel filtration experiments demonstrated definitively that the yeast-expressed HemA protein corresponded to GluTR45. Furthermore, analysis of GluTR activity in an E. coli strain with a disrupted hemA gene displayed GluTR85, but not GluTR45 activity. The hemA gene from Synechocystis 6803 was cloned by functional complementation in E. coli. DNA sequence analysis revealed an open reading frame capable of encoding a 427-amino acid polypeptide (molecular mass of 47,525 Da). The Synechocystis 6803 amino acid sequence shows significant similarity upon alignment with HemA sequences from E. coli, Bacillus subtilis, Salmonella typhimurium, and Chlorobium vibrioforme but does not contain the amino acid sequence derived from the N terminus of the previously purified GluTR protein (Rieble, S., and Beale, S. I. (1991) J. Biol. Chem. 266, 9740-9745). These experiments are the first direct demonstration of GluTR activity of the HemA protein and provide further evidence for two pathways of ALA formation in prokaryotes.

Synthesis and secretion of immunoreactive methionine-enkephalin from rabbit reproductive tissues in vivo and in vitro

The expression of the proenkephalin gene has been demonstrated in the reproductive tissues of several animal species. The objectives of the experiments reported here were to (a) examine the presence of immunoreactive methionine-enkephalin (ir-MENK) in rabbit ovary, oviduct, and uterus and in a rabbit endometrial cell line (HRE-H9), (b) characterize ir-MENK biochemically, (c) investigate the effect of eCG + hCG treatment on the synthesis and secretion of ir-MENK in vivo, and (d) study the effect of K+ depolarization on the secretion of ir-MENK from HRE-H9 cells. Uterine fluid was collected by flushing the uterine lumen with saline. Reproductive tissues and HRE-H9 cells were extracted with 0.1 N acetic acid. Both the uterine fluid and extracts of uterus, ovary, oviduct, and HRE-H9 cells exhibited inhibition curves parallel to that of authentic MENK in the MENK RIA system. Sephadex G-15 gel filtration profiles indicated that in the extracts of rabbit uterus and HRE-H9 cells, most ir-MENK co-eluted with standard MENK, with a minor portion eluting near the void volume (Vo). Reverse-phase-HPLC (RP-HPLC) profiles showed a major peak coinciding with standard MENK, plus a minor peak of highly hydrophilic ir-MENK. The effect of eCG + hCG treatment was studied by i.m. injection of eCG (150 IU), followed by i.v. injection of hCG (75 IU) 4 days later. Ir-MENK concentration in the uteri and ovaries was significantly (p less than 0.05) increased (9.06 +/- 1.89 and 2.05 +/- 0.32 ng/mg protein, respectively), compared to control levels (2.31 +/- 0.86 and 0.24 +/- 0.77).(ABSTRACT TRUNCATED AT 250 WORDS)

Utilisation of pearl millet (Pennisetum typhoides) for egg production

1. The performance of White Leghorn laying hens on diets providing pearl millet (Pennisetum typhoides) at 300 and 600 g/kg to replace maize, part per part, or "maize mix" isoenergetically and isonitrogenously in the first experiment and at 600 g/kg diet to replace maize in toto, part per part, in the second experiment were examined. In the first experiment, 3 groups of 12 laying hens were placed on each of the 5 dietary treatments for 3 x 28 d, whereas in the second experiment, each of the two diets was offered to 10 groups of 15 laying hens for 6 x 28 d. 2. Inclusion of pearl millet in the diet at the expense of maize, part per part, did not significantly influence hen-day egg production, feed intake, feed efficiency and body weight in either experiment. Incorporation of pearl millet isoenergetically at the expense of "maize mix" at any level, i.e. 300 g or 600 g/kg (Experiment 1), also did not influence hen-day egg production but at the end of periods 2 and 3 did result in decreased feed intakes with consequent improvements in feed efficiency. 3. Egg weight in general showed a tendency to improve with diets providing pearl millet at 600 g/kg. 4. Profits from egg sales over feed cost were directly proportional to the inclusion of pearl millet in the diet either at the expense of maize, part per part, or "maize mix" isoenergetically.

Mono Q chromatography permits recycling of DNA template and purification of RNA transcripts after T7 RNA polymerase reaction

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Prolongation of allograft survival in diabetic rats treated with cyclosporine by deoxyguanosine pretreatment of pancreatic islets of Langerhans

In vitro pretreatment of islets of Langerhans with deoxyguanosine (dGuo) has been shown to be effective for the prolongation of islet allograft survival in rats. [This study evaluates the effect of pretreatment of islets with dGuo transplanted into CsA-treated recipients.] Transplantation of dGuo-treated islets from Wistar rats into diabetic hooded (PVG) rats resulted in 36% graft survival without immunosuppression (dGuo-group) and 89% islet survival after a short course of cyclosporine was used in recipients (dGuo + CsA group). In contrast, transplantation of untreated islets into rats without immunosuppression (controls) and with CsA (CsA group) immunosuppression resulted in 0 and 56% survival, respectively. The differences in graft survival between dGuo versus control group (P less than 0.001), (dGuo + CsA) versus control group (P less than 0.0001), and CsA versus control group (P less than 0.002) are statistically significant. Donor-strain skin-graft challenge failed to induce rejection of transplanted normoglycemic rats in (dGuo) and (dGuo + CsA) groups. The results indicate that a state of immunologic unresponsiveness may have been induced in the recipients of dGuo-treated islets, and further treatment with CsA synergistically prolongs islet survival in fully mismatched rats.

Effect of nitrous oxide on the concentrations of opioid peptides, substance P, and LHRH in the brain and beta-endorphin in the pituitary

Many studies have indicated that nitrous oxide (N2O) exposure results in specific effects on the reproductive system, some of which are antigonadotropic. The neurochemical events regulating the pituitary-gonadal axis are probably influenced by N2O, but precise documentation is lacking. The effects of exposure to 30% N2O in air on the brain tissue concentrations of luteinizing hormone releasing hormone (LHRH), substance P (SP), met-enkephalin, and beta-endorphin and on beta-endorphin concentrations of the pituitary gland are described in this study. Female rats were exposed to either N2O or air for 8 hr a day over one estrous cycle, and the brain and pituitary tissues were collected and processed. Neuropeptide concentrations were measured by specific radioimmunoassays. Exposure to N2O resulted in significant elevation of LHRH in the preoptic area, with a concomitant decrease in SP. The SP concentration of the medial basal hypothalamus was significantly elevated in N2O-exposed animals. Exposure to N2O resulted in significant increases in met-enkephalin in the brainstem area and beta-endorphin in the pituitary. These results suggest that exposure to N2O alters the interactive neural system activity regulating gonadotropin secretion from the pituitary. The significance of increased met-enkephalin in the brainstem of N2O-exposed animals is not known.

Glycosidic bond cleavage of 5-fluoro-2'-deoxyuridine and 5-fluorouridine by amino acyl-tRNA synthetases

Lysyl-tRNA synthetase isolated from rat liver cleaves glycosidic bond of 5-Fluorouridine and 5-Fluoro-2'-deoxyuridine to generate 5-Fluorouracil. The generation of 5-Fluorouracil was monitored by cellulose thin layer chromatography and by spectrophotometry. The enzyme was found to be 1.4 fold more efficient in cleaving the glycosidic bond of 5-Fluoro-2'-deoxyuridine than 5-Fluorouridine.

Effect of early exposure to delta-9-tetrahydrocannabinol on the levels of opioid peptides, gonadotropin-releasing hormone and substance P in the adult male rat brain

The effects of neonatal exposure to delta-9-tetrahydrocannabinol (THC) on the adult animal brain neurochemistry and pain perception were evaluated. Newborn rat pups were culled to a litter size of 8 (males and females) and treated either with THC (2 mg/kg) or oil (control) daily, during days 1-4 after birth. After weaning, the THC-treated males were housed 4 per cage. During the juvenile period (day 50), the THC-treated animals exhibited significantly lower baseline tail-flick values (a measure of pain perception) than the control. However, as adults, the THC-treated animals exhibited significantly higher sensitivity to pain following 5 mg/kg morphine challenge. Furthermore, the THC-treated animals had significantly elevated beta-endorphin and methionine-enkephalin levels in almost all the brain areas sampled for the study. In addition, the neonatally THC-treated rats exhibited significantly higher levels of substance P (SP) and significantly lower levels of gonadotropin releasing hormone (GnRH) in the anterior hypothalamus-preoptic area. The SP and GnRH levels did not differ among the THC-treated and control animals in the medial basal hypothalamus. The results of this study indicate that even a very low dose of THC administered during the neonatal period has a long-lasting effect on the brain neurochemistry. In particular, neonatal administration of THC appears to alter functioning of the endogenous opioid system.