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Parallel robotic mechanisms are generally used in flight simulators with a motion-cueing algorithm to create an unlimited motion feeling of a simulated medium in a bounded workspace of the simulator. A major problem in flight simulators is that the simulation has an unbounded space and the manipulator has a limited one. Using a washout filter in the motion-cueing algorithm overcomes this. In this study, a low-cost six degrees of freedom (DoF) desktop parallel manipulator is used to test a classical motion-cueing algorithm; the algorithm's functionality is confirmed with a Simulink real-time environment. Translational accelerations and angular velocities of the simulated medium obtained from FlightGear flight simulation software are processed through a generated washout filter algorithm and the simulated medium's motion information is transmitted to the desktop parallel robotic mechanism as a set point for each leg. The major issues of this paper are designing a desktop simulation system, controlling the parallel manipulator, communicating between the flight simulation and the platform, designing a motion-cueing algorithm and determining the parameters of the washout filters.

BACKGROUND: Chronic lymphocytic leukemia is an uncommon type of leukemia in Iraq, although many reported cases of chronic lymphocytic leukemia in the Iraqi Kurdistan region are of high risk stage. Staging of chronic lymphocytic leukemia is essential in treatment planning and for disease prognosis. the aims of this study were to find out the difference in patients' survival with early and late clinical stages, and to evaluate CLL outcome in relation to the Rai and Binet staging. PATIENTS AND METHODS: This retrospective cross-sectional analysis studied 250 patients, 170 male and 80 female, with chronic lymphocytic leukemia who were registered in three hemato-oncology centers in Iraqi Kurdistan for the last 10 years. The diagnosis of the disease was made according to the guideline of the International Workshop Chronic Lymphocytic Leukemia update of the National Cancer Institute. The patients' clinical staging was determined by a senior hematologist based on the clinical and laboratory findings. RESULTS: The mean age of the patients was 63(±11.8) years, 40% were >65 years. The median survival was 27 months. Elderly patients >65 years had significantly lower mean survival. The Rai staging was distributed as follows: stage 0 (24.8%), stage I (12.8%), stage II (30.8%), stage III (9.6%) and stage IV (22%). The median survival was significantly higher among patients with Rai stage 0 comparing to patients with advanced stages (P

OBJECTIVES : There are the variable degrees of bone marrow (BM) infiltration patterns in chronic lymphocytic leukemia (CLL). Four BM patterns: Interstitial, nodular, mixed, and diffuse patterns were identified. The aim of this study is to assess the effects of BM infiltration patterns on the disease outcome among CLL patients in Kurdistan Region of Iraq. METHODS: This study is a cross-sectional, descriptive, retrospective involved 106 patients with CLL disease. The data are collected in the Kurdistan region of Iraq (including Erbil, Sulaymaniyah, and Duhok) cancer centers. Through the period from January 1, 2010 to December 31, 2019. BM histopathology study of all patients was assessed and correlated with the disease outcome. RESULTS: Fifty-three (50.0%) patients had interstitial BM patterns, 17 (16.0%) had nodular BM pattern, 14 (13.2%) had mixed BM patterns, and 22 (20.8%) had diffuse BM pattern. The results showed that patients with interstitial, nodular, and mixed BM patterns had a superior overall survival (OS) and progression-free survival (PFS) rate than diffuse BM pattern. Kaplan–Meier curve illustrates that our CLL patients with interstitial BM patterns had a better mean OS rate (44.0 months) than diffuse BM pattern with a mean of (23.2 months). As well as for PFS, the mean was (35.7 months) for the interstitial BM patterns and (17.6 months) for diffuse BM pattern. CONCLUSIONS: We demonstrate that the BM involvement patterns have a prognostic value in our CLL patients and provide more reliable information regarding the clinical outcome.

BACKGROUND: The clinical course of patients with chronic lymphocytic leukemia (CLL) is heterogeneous. Certain patients go through a brisk illness progression, and others stay alive for quite a long time without requiring treatment. OBJECTIVE: This study was conducted to evaluate the impact of clinical staging, age, gender, and treatment initiation on the survival of CLL patients in Kurdistan-Iraq. MATERIALS AND METHODS: A total of 239 CLL patients from Oncology Centers from Kurdistan-Iraq were enrolled in a retrospective study from January 1, 2010, to December 31, 2020. A standardized questionnaire was used to obtain demographics data, presenting features, blood investigations, and imaging results. The diagnosis and treatment assessment was based on the International Workshop of CLL, and clinical staging was performed using both Rai and Binet classifications. There were two groups of patients (watch and wait) and (treated) groups. RESULTS: The median age at the diagnosis was 64 years old with a male: female ratio of 2.3:1. Eighty-three patients (34.7%) were diagnosed incidentally and about one-third of the patients presented with advanced stage, and also, 62.3% of the patients received therapy throughout the study period. The 3-year overall survival was (81.1%) (95% confidence interval 74.3%–87.9%). Of particular interest to report that advanced age, Binet Stage C, and hemoglobin

BACKGROUND: Chronic lymphocytic leukemia (CLL) is characterized by a lower incidence rate in Iraq and Kurdistan as compared to Western countries. However, a good prognosis of CLL is dependable on diagnosis, risk stratification, and a better choice of an appropriate treatment regimen. AIM OF THE STUDY: To evaluate the effectiveness of fludarabine, cyclophosphamide, and rituximab (FCR) regimen in comparison to other chemotherapy regimens in the management of patients with CLL in Kurdistan region/Iraq. PATIENTS AND METHODS: A retrospective review study carried out in three cancer centers in the Kurdistan region of Iraq for the duration of 10 years through the period from January 1, 2010 to December 31, 2019, on 152 CLL patients. CLL was diagnosed according to the International Workshop on CLL. The treatment of CLL patients was either by FCR chemo-immunotherapy regimen or other chemotherapies. RESULTS: The FCR chemo-immunotherapy was the treatment of 38.8% of CLL patients, while 61.2% of CLL patients were treated by other chemotherapies. There was a significant association between younger age patients and the use FCR chemo-immunotherapy (P = 0.001). There was a significant association between a complete response and treatment by FCR chemo-immunotherapy (P = 0.02). The mean overall survival duration and progression-free survival of CLL patients treated by FCR chemo-immunotherapy were significantly longer than the mean survival time of CLL patients treated by other chemotherapies (P = 0.01). CONCLUSIONS: Complete response and survival of CLL patients treated by FCR chemo-immunotherapy were better than the complete response and survival of CLL patients treated by other chemotherapies.

Su kaynaklarındaki kıtlık, nüfusu, artan ihtiyaçlarını karşılamak için kendi kuıyularını açmaya ve yer altı suyunu çekmeye zorlamıştır. Çalışma alanı, Irak’ta buğday, arpa, mercimek ve sebze gibi ürünlerin ekildiği ve büyükbaş hayvan yetiştiriciliğinin yapıldığı başlıca zirai alanlardan biridir. Yer altı suyu örneklerinin kimyasal özelliklerinin incelenmesinin önemi, litolojik birimlerin ve suyun karşılıklı etkileşiminin ve, doğal çözülme süreç­leri yüzünden artan doğal çözünmüş tuz konsantrasyonlarının bilinmesi açısından önemlidir. Telkaif bölgesin­den alınan yer altı suyu örneklerinin kimyasal özellikleri, ev içi ve zirai kullanım için özelliklerinin belirlenmesi amacıyla 14 örnekte incelenmiştir. Yeraltı suyu örneklerinin elektrik iletkenliği (Ec), pH, toplam çözünmüş katilar (TDS), Na+, K+, Ca+2, Mg+2, HC03_1, S04-2, N03_1,CM konsantrasyonları ve toplam sertlik (TH) gibi fiziksel ve kimyasal özellikleri belirlenmiştir. Piper diyagramı kullanılarak, yeraltı sularının uygunluğu, türü ve jeokimyasal gelişmelerinin gösterilmesi için grafik olarak hidrokimyasal parametreleri de analiz edilmiştir. Yer altı suyunun sulama için uygunluğunun gösterilmesi için Richard (1954) ve Wilcox (1955) sınıflamaları da kullanılmıştır. Çalışma alanına yayılmış olan kuyulardan Al-Fatha, Injana litolojik birimleri ve Kuvaterner akiferler tanımlanmış ve incelenmiştir. Bölgedeki yer altı suları yağmur sularından ve suyu toplama havzalarına ulaştıran vadilerden beslenmektedir, inceleme alanının yer altı suyu kimyası yeraltı suyu örneklerinin çoğunun CaHC03 and CaS04 türünde sular olduğunu göstermekte; örneklerde toplam sertlik (TH) ve toplam çözünmüş katilar (TDS) yüksek olup bunlar genellikle düşük alkali değerlerine sahiptir

Aims: Ferric carboxymaltose (FCM) is guideline-recommended for iron deficiency (ID) in heart failure with reduced ejection fraction (HFrEF). Despite a well-established safety profile, the magnitude and clinical significance of FCM-induced hypophosphataemia in HFrEF remains unclear. This pre-specified substudy of HEART-FID evaluated serum phosphate, 1,25-dihydroxyvitamin D, and plasma parathyroid hormone (PTH) subsequent to FCM., Methods and Results: HEART-FID was a randomized, double-blind, placebo-controlled trial of ambulatory patients with HFrEF and ID randomized to FCM versus placebo. This substudy assessed mean change from baseline across eight visits over 6 months for the following endpoints: serum phosphate, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and PTH, in addition to the clinical severity of potential hypophosphataemia. Overall, 133 patients (n = 62 FCM, n = 71 placebo) were prospectively enrolled. Mean age was 68 ± 11 years, 55 (41.4%) were women, and 29 (21.8%) had chronic kidney disease. Phosphate levels decreased in 34 (57.6%) patients in the FCM group compared with 7 (10.3%) in the placebo group. Mean change in phosphate levels reached a nadir at day 21 (-0.36 ± 0.27 mmol/L) subsequent to FCM infusion with 28 (51%) having moderate-to-severe hypophosphataemia. Reductions in 1,25-dihydroxyvitamin D were also observed, whilst PTH increased. These biochemical changes returned to baseline levels by day 91. Serum levels of 25-hydroxyvitamin D remained stable throughout the study. No serious adverse events associated with hypophosphataemia were reported., Conclusions: Transient moderate-to-severe hypophosphataemia was frequent subsequent to FCM infusion, accompanied by 1,25-dihydroxyvitamin D decrease and PTH increase. Serum levels of 25-hydroxyvitamin D remained stable. No evidence of symptomatic hypophosphataemia was reported, collectively indicating FCM-related hypophosphataemia to be clinically benign and transient in HFrEF., (© 2024 The Author(s). European Journal of Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Background: Iron deficiency anemia (IDA) is a common cause of fatigue and impaired quality of life. The present study aimed to evaluate the impact of intravenous iron supplementation with ferric carboxymaltose (FCM) on fatigue, physical function, and general health among patients with IDA attending routine clinical care., Methods: This was a prospective, single arm, observational study of adult patients prescribed with intravenous FCM for the treatment of IDA during routine clinical care. We used Patient-Reported Outcomes Measurement Information System (PROMIS) instruments to evaluate fatigue (PROMIS Short Form v1.0 13a [FACIT-Fatigue]), general health status (PROMIS Scale v1.2), and physical function (PROMIS Short Form v2.0 4a) before and at 3 and 6 months after FCM treatment., Results: A total of 152 patients were enrolled. Mean age was 47.4 ± 16.0 years and 82.2% were female. Mean serum hemoglobin was 10.2 ± 1.4 g/dL at baseline. All patients were treated with at least one FCM dose at baseline, with 77.6% receiving a two-dose treatment course. The mean baseline FACIT-Fatigue score was 61.0 ± 9.0, improving significantly to 50.2 ± 9.5 at 3 months after FCM treatment. A minimum 5-point improvement, pre-defined as clinically meaningful, was seen in the FACIT-Fatigue, PROMIS Global Physical Health, Global Mental Health and PROMIS Physical Function scores for 72.7%, 52.8%, 41.7% and 39.8% of patients at 3 months (p < 0.0001 for each change from baseline), with statistically significant improvement continuing at 6 months. Mean serum hemoglobin was significantly increased at both 3 and 6 months (12.8 g/dL [N = 44] and 12.4 g/dL [N = 54], respectively)., Conclusion: IDA patients attending routine clinical practice reported substantial levels of fatigue and impairments in physical function and global health prior to intravenous iron treatment. Patients experienced significant improvements in fatigue symptoms, physical function, and global health at 3 months after treatment with FCM, which were sustained at 6 months., Competing Interests: Winghan J Kwong is an employee of Daiichi Sankyo, the study sponsor. Syed Numan is an employee of American Regent, a Daiichi Sankyo Group Company. Tina D. Hunter and Dalila Alves are employees of CTI Clinical Trial & Consulting, which is a consultant to Daiichi Sankyo, the study sponsor. Anish Patel is a consultant for AbbVie and a speakers bureau member for Bristol Myers Squibb, Janssen, and Takeda. Satish Shanbhag is a consultant for Beigene and Takeda. The authors report no other conflicts of interest in this work., (© 2023 Kwong et al.)

Introduction and Objective: Intravenous iron preparations rapidly correct iron deficiency anemia, with the notable drug class effect of rare, yet potentially life-threatening, administration-related hypersensitivity or anaphylactic reactions. The objective of this comparative study was to assess adverse events associated with four intravenous iron preparations and estimated medical costs, in the US Food and Drug Administration Adverse Event Reporting System (FAERS) database., Methods: Cases of hypersensitivity reactions and anaphylaxis/anaphylactic shock associated with iron dextran, iron sucrose, ferumoxytol, and ferric carboxymaltose, spontaneously reported to FAERS (1 January, 2014 to 31 December, 2019), were extracted. The reporting odds ratio lower bound 90% confidence interval (ROR05) > 1 and cases ≥ 5 defined a likely signal for a drug-adverse event association. Adverse event-associated medical costs were estimated using Agency for Healthcare Research and Quality/Healthcare Cost and Utilization Project 2016 data., Results: For hypersensitivity reactions, ferumoxytol and iron dextran had the highest ROR05 values (5.00 and 4.35, respectively) and greatest proportions of associated deaths (7.1% and 5.3%), followed by iron sucrose (ROR05 3.94, deaths 2.4%), and ferric carboxymaltose (ROR05 3.03, deaths 0.2%). For anaphylaxis/anaphylactic shock, ROR05 for cases/deaths were: 39.32/13.4%, ferumoxytol; 37.80/4.5%, iron dextran; 17.60/4.7%, iron sucrose; and 8.77/no deaths, ferric carboxymaltose. Downstream medical costs per adverse event were highest with iron dextran (US$8615) and ferumoxytol (US$8164), followed by iron sucrose (US$4212), and ferric carboxymaltose (US$1832)., Conclusions: Reporting rates of hypersensitivity and anaphylaxis with intravenous iron preparations were highest with ferumoxytol and lowest with ferric carboxymaltose in the US FAERS database. Adverse event-related medical costs were highest for iron dextran and ferumoxytol, and lowest for ferric carboxymaltose.

Objective: To explore current recommendations for intravenous (IV) iron use in clinical guidelines for iron deficiency anemia (IDA) across different therapeutic areas and identify recommendations, if any, for the treatment of IDA., Methods: A literature search was conducted in Medline, EMBASE, BIOSIS, Cochrane Collaboration, and on websites of relevant professional associations. Searches were limited to English publications. 1292 citations were identified, 219 papers were assessed, and 35 guidelines were identified for inclusion., Results: The guidelines covered a variety of geographies: United States (US; n  = 10); Europe ( n  = 11); "Rest-of-World" ( n  = 9); and "Other" organizations ( n  = 5). These covered a variety of specialties. Guidelines defined iron deficiency and IDA generally by serum ferritin and transferrin saturation levels. One-fifth of the reviewed guidelines (7 of 35) included no mention or recommendation regarding parenteral iron's utility in the management of IDA. Fifteen guidelines recommended using parenteral iron in the management of IDA. Fewer US guidelines included recommendations around IV iron than in Europe or the rest of the world. Approximately 60% of the guidelines have not been updated in ≥5 years and consequently do not reflect current evidence on the safety and efficacy of IV iron., Conclusions: While national and international guidelines for management of IDA exist, many are outdated and do not reflect current evidence including, but not limited to, parenteral iron use. Urgent consideration should be given to updating and clarifying management guidelines for IDA using the latest treatment modalities and options, particularly in the US.

Tumor necrosis factor (TNF) inhibitors are widely used biologics for the treatment of several chronic inflammatory diseases. The launch of anti-TNF biosimilars has introduced the possibility of non-medical switching between originator biologics and their biosimilars. However, the potential clinical and patient-reported consequences of non-medical switching remain largely unknown, as much of the evidence comes from poorly or uncontrolled real-world evidence (RWE) studies that often have an element of bias and nonstandardized outcome measures. To appropriately evaluate the safety, efficacy, and immunogenicity of non-medical switching from an originator to its biosimilar, we propose that seven key study design elements should be considered when assessing the existing evidence: studies should be (1) randomized and double-blind, (2) adequately controlled, and (3) adequately powered; include (4) multiple switching, (5) an assessment of immunogenicity, and (6) adequate follow-up duration; and (7) report individual patient-level outcomes. This systematic review assessed the robustness and consistency of the current non-medical switching evidence, with a focus on TNF inhibitors. A comprehensive literature search (January 2012-February 2018) identified 98 publications corresponding to 91 studies (17 randomized controlled trials and 74 RWE studies) describing non-medical switching from a TNF inhibitor originator to its biosimilar. When assessing the totality of this evidence, none of the non-medical switching studies conducted to date were found to use all seven of the key design elements, and the absence of these elements dilutes the robustness of the data. Furthermore, discontinuation rates varied widely among studies (0-87%), suggesting heterogeneity and inconclusiveness of the current efficacy, safety, and immunogenicity evidence, particularly at an individual patient level. Therefore, patients should not be indiscriminately switched from an originator TNF inhibitor to its biosimilar for non-medical reasons. Switching decisions should remain between the treating physicians and their patients and be made on a case-by-case basis, relying upon robust scientific evidence., Funding: AbbVie.Plain Language Summary: Plain language summary available for this article.

Decreased availability or efficacy of neurotrophic factors may underlie an increased susceptibility of mesencephalic dopaminergic cells to age-related degeneration. Neuregulins (NRGs) are pleotrophic growth factors for many cell types, including mesencephalic dopamine cells in culture and in vivo. The functional NRG receptor ErbB4 is expressed by virtually all midbrain dopamine neurons. To determine if levels of the NRG receptor are maintained during aging in the dopaminergic ventral mesencephalon, expression of ErbB4 mRNA and protein was examined in young (3 months), middle-aged (18 months), and old (24-25 months) Brown Norway/Fischer 344 F1 rats. ErbB4 mRNA levels in the substantia nigra pars compacta (SNpc), but not the adjacent ventral tegmental area (VTA) or subtantia nigra pars lateralis (SNl), were significantly reduced in the middle-aged and old animals when compared to young rats. Protein expression of ErbB4 in the ventral midbrain was significantly decreased in the old rats when compared to the young rats. Expression of tyrosine hydroxylase (TH) mRNA levels was significantly reduced in the old rats when compared to young animals in the SNpc, but not in the VTA or SNI. TH protein levels in the ventral midbrain were also decreased in the old animals when compared to the young animals. These data demonstrate a progressive decline of ErbB4 expression, coinciding with a loss of the dopamine-synthesizing enzyme TH, in the ventral midbrain of aged rats, particularly in the SNpc. These findings may implicate a role for diminished NRG/ErbB4 trophic support in dopamine-related neurodegenerative disorders of aging such as Parkinson's disease.

In a pilot study, the feasibility of immune whey protein concentrate (40%; immune WPC-40) to aid the prevention of relapse of Clostridium difficile diarrhoea was evaluated. Immune WPC-40 was made from milk after immunization of Holstein-Frisian cows with C. difficile-inactivated toxins and killed whole-cell C. difficile. Immune WPC-40 contained a high concentration of specific sIgA antibodies, and was effective in neutralizing the cytotoxic effect of C. difficile toxins in cell assays in vitro. Immune WPC-40 conferred protection from otherwise lethal C. difficile-associated caecitis in hamsters. To obtain preliminary data in humans, 16 patients (10 male; median 57 years) with toxin- and culture-confirmed C. difficile diarrhoea were enrolled in an uncontrolled cohort study. Nine had a history of relapsing C. difficile diarrhoea. After completion of standard antibiotic treatment, the patients received immune WPC-40 TID for 2 weeks; it was well tolerated and no treatment-related adverse effects were observed. In all but one case, C. difficile toxins had disappeared from the faeces upon completion of treatment. During a follow-up period of median 333 days (range 35 days to 1 year), none of the patients had suffered another episode of C. difficile diarrhoea. These preliminary data suggest that immune whey protein concentrate-40 may be of help in the prevention of relapse of C. difficile diarrhoea.

Neurotrophins are a group of structurally related polypeptides that support the survival, differentiation, and maintenance of neuronal populations that express the appropriate high-affinity neurotrophin receptors. Two members of the neurotrophin family, brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), have been shown to increase the survival of dopaminergic neurons from the ventral midbrain in vitro. Evidence suggests that ventral midbrain neurons might be able to derive support from these trophic factors in vivo through paracrine or autocrine interactions. Both BDNF and NT-3 mRNAs and their receptor mRNAs, trkB and trkC mRNAs, respectively, have been localized to the ventral mesencephalon. However, the relative expression levels of the neurotrophins and their receptor mRNAs throughout ontogeny and in adulthood have not been elucidated. In the present study, the postnatal developmental expression of BDNF, NT-3, trkB, and trkC mRNAs was analyzed via in situ hybridization to gain insight into the possible roles of these factors in vivo. We found that there was a developmental decline in the expression of BDNF and NT-3 mRNAs in the ventral mesencephalon. In contrast, no alterations in the expression of midbrain trkB or trkC mRNAs could be discerned. The present results suggest a role for BDNF and NT-3 in the earlier postnatal developmental events of responsive populations. The continued, albeit lower, expression of the neurotrophins in the ventral mesencephalon in adulthood also suggests a role for these factors in mature neuronal systems.

Niemann-Pick disease is caused by a genetic deficiency in acid sphingomyelinase (ASM) leading to the intracellular accumulation of sphingomyelin and cholesterol in lysosomes. In the present study, we evaluated the effects of direct intracerebral transplantation of neural progenitor cells (NPCs) on the brain storage pathology in the ASM knock-out (ASMKO) mouse model of Type A Niemann-Pick disease. NPCs derived from adult mouse brain were genetically modified to express human ASM (hASM) and were transplanted into multiple regions of the ASMKO mouse brain. Transplanted NPCs survived, migrated, and showed region-specific differentiation in the host brain up to 10 weeks after transplantation (the longest time point examined). In vitro, gene-modified NPCs expressed up to 10 times more and released five times more ASM activity into the culture media compared with nontransduced NPCs. In vivo, transplanted cells expressed hASM at levels that were barely detectable by immunostaining but were sufficient for uptake and cross-correction of host cells, leading to reversal of distended lysosomal pathology and regional clearance of sphingomyelin and cholesterol storage. Within the host brain, the area of correction closely overlapped with the distribution of the hASM-modified NPCs. No correction of pathology occurred in brain regions that received transplants of nontransduced NPCs. These results indicate that the presence of transduced NPCs releasing low levels of hASM within the ASMKO mouse brain is necessary and sufficient to reverse lysosomal storage pathology. Potentially, NPCs may serve as a useful gene transfer vehicle for the treatment of CNS pathology in other lysosomal storage diseases and neurodegenerative disorders.

Although the distribution of estrogen receptor beta (ERbeta) immunoreactivity in the rat central nervous has been reported, no such data are available in the mouse. The present study used in vivo autoradiography utilizing a (125)I-estrogen that has equal binding affinity for both receptors as well as immunohistochemistry for ERbeta and ERalpha, to investigate and compare the distribution of the two ERs in the mouse CNS. The use specific antisera against ERalpha and ERbeta allowed us to evaluate the contribution of these receptors to the binding detected with autoradiography. In addition, data were collected in ovariectomized wildtype and ERalpha KO (knockout) mice to examine developmental regulation of ERbeta expression by ERalpha. These studies revealed that in the mouse CNS, combining immunoreactivity for ERalpha with that for ERbeta accounted for all regions where binding was seen using autoradiography. Therefore, these data strongly suggest that the major contributors of estrogen binding in the mouse CNS are ERalpha and ERbeta. Together, these data provide an anatomical foundation for future studies and advance our understanding of estrogen action in the CNS. Moreover, since the immunocytochemical images were similar in wildtype and ERalpha KO mice, these studies suggest that the lack of ERalpha does not influence the expression of ERbeta in the central nervous system., (Copyright 2004 Wiley-Liss, Inc.)

Neurotrophic signaling pathways have been implicated in the maintenance of the mesolimbic dopamine system, as well as in changes in this system induced by chronic morphine exposure. We found that many of these signaling pathway proteins are expressed at appreciable levels within the ventral tegmental area (VTA) and related regions, although with substantial regional variation. Moreover, phospholipase Cgamma1 (PLCgamma1) was significantly and specifically up-regulated within the VTA by 30% following chronic exposure to morphine. PLCgamma1 mRNA expression is enriched in dopaminergic neurons within the VTA; however, the up-regulation of PLCgamma1 in this region was not seen at the mRNA level. In contrast to PLCgamma1, insulin receptor substrate (IRS)-2, a protein involved in phosphatidylinositol 3-kinase signaling, and another putative IRS-like protein were significantly down-regulated within the VTA by 49 and 45%, respectively. Levels of several proteins within the Ras-ERK pathway were not altered. Regulation of neurotrophic factor signaling proteins may play a role in morphine-induced plasticity within the mesolimbic dopamine system.

The insulin receptor substrate (IRS) proteins are a family of important regulatory adapters that mediate the coupling between receptor-associated tyrosine kinases and downstream effectors including phosphatidylinositol-3'-kinases (PI-3-Ks). In the present study, the distribution of IRS-4 mRNA was determined in rat brain by in situ hybridization. IRS-4 mRNA was widely expressed throughout the hypothalamus, with the most dense labeling observed in the medial preoptic nucleus, ventromedial hypothalamus, and arcuate nucleus. In contrast, and unlike IRS-1 or IRS-2, expression of IRS-4 mRNA in other forebrain and midbrain regions was much more restricted. The expression of IRS-4 mRNA in the hypothalamus suggests a specific role for this factor in the signaling of one or more receptors involved hypothalamic functions including feeding, lactation, sexual and parental behaviors.

The documented trophic actions of the neurotrophins brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and neurotrophin-4/5 (NT-4/5) upon ventral mesencephalic dopamine neurons in vitro and in vivo are presumed to be mediated through interactions with their high-affinity receptors TrkB (for BDNF and NT-4/5) and TrkC (for NT-3). Although both neurotrophin receptor mRNAs have been detected within the rat ventral midbrain, their specific association with mesencephalic dopaminergic cell bodies remains to be elucidated. The present study was performed to determine the precise organization of trkB and trkC mRNAs within rat ventral midbrain and to discern whether the neurotrophin receptor mRNAs are expressed specifically by dopaminergic neurons. In situ hybridization with isotopically labeled cRNA probes showed that trkB and trkC mRNAs were expressed in all mesencephalic dopamine cell groups, including all subdivisions of the substantia nigra and ventral tegmental area, and in the retrorubral field, rostral and caudal linear raphe nuclei, interfascicular nucleus, and supramammillary region. Combined isotopic/nonisotopic double-labeling in situ hybridization demonstrated that virtually all of the tyrosine hydroxylase (the catecholamine biosynthetic enzyme) mRNA-containing neurons in the ventral midbrain also expressed trkB or trkC mRNAs. Additional perikarya within these regions expressed the neurotrophin receptor mRNAs but were not dopaminergic. The present results demonstrate that essentially all mesencephalic dopaminergic neurons synthesize the neurotrophin receptors TrkB and TrkC and thus exhibit the capacity to respond directly to BDNF and NT-3 in the adult midbrain in vivo. Moreover, because BDNF and NT-3 are produced locally by subpopulations of the dopaminergic cells, the present data support the notion that the neurotrophins can influence the dopaminergic neurons through autocrine or paracrine mechanisms.

The neurotrophins brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) and their receptors trkB and trkC, respectively, are expressed in the locus coeruleus (LC) and ventral tegmental area (VTA), brain regions known to be involved in opiate addiction. Previously, administration of exogenous neurotrophins has been shown to oppose effects of chronic morphine treatment on LC and VTA neurons. However, the response of endogenous neurotrophins in LC and VTA to opiate treatment is unknown. In this study, BDNF, NT-3, trkB, and trkC mRNAs were analyzed in these regions after chronic morphine treatment and during antagonist precipitated withdrawal. Although chronic morphine exposure resulted in only modest increases in BDNF and NT-3 mRNA expression in LC, precipitated withdrawal led to a marked, rapid, and prolonged increase in BDNF mRNA and a delayed decrease in NT-3 mRNA. Levels of trkB and trkC mRNAs, which were unchanged by chronic morphine treatment, were elevated in LC at 2 and 6 hr of withdrawal. By 20 hr, trkB mRNA levels in LC had returned to control, whereas trkC mRNA levels fell below control values. In contrast to the substantial alterations observed in LC, there was no regulation of the neurotrophins or trk mRNAs within the VTA during chronic opiate treatment or withdrawal, with the exception of an increase in trkB mRNA at 6 hr of withdrawal. These results suggest that neurotrophins and their receptors per se may be involved in opiate-induced plasticity of the LC, whereas other mechanisms would appear to be involved in the VTA.

Previous studies have suggested that the neurotrophins brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) are neuroprotective or neurotrophic for certain subpopulations of hippocampal neurons following various brain insults. In the present study, the expression of BDNF and NT-3 mRNAs in rat hippocampus was examined after traumatic brain injury. Following lateral fluid percussion (FP) brain injury of moderate severity (2.0-2.1 atm) or sham injury, the hippocampi from adult rats were processed for the in situ hybridization localization of BDNF and NT-3 mRNAs using 35S-labeled cRNA probes at post-injury survival times of 1, 3, 6, 24 and 72 h. Unilateral FP injury markedly increased hybridization for BDNF mRNA in the dentate gyrus bilaterally which peaked at 3 h and remained above control levels for up to 72 h post-injury. A moderate increase in BDNF mRNA expression was also observed bilaterally in the CA3 region of the hippocampus at 1, 3, and 6 h after FP injury, but expression declined to control levels by 24 h. Conversely, NT-3 mRNA was significantly decreased in the dentate gyrus following FP injury at the 6 and 24 h survival times. These results demonstrate that FP brain injury differentially modulates expression of BDNF and NT-3 mRNAs in the hippocampus, and suggest that neurotrophin plasticity is a functional response of hippocampal neurons to brain trauma.

The tyrosine kinase receptors trkB and trkC are essential components of the high-affinity receptors for members of the neurotrophin family, including brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3). Both neurotrophin receptor mRNAs are broadly distributed throughout the caudate-putamen. In animal models of Parkinson's disease, loss of the ventral mesencephalic dopamine projection to the striatum has been shown to alter the expression of several striatal peptides, neurotransmitter-synthesizing enzymes and receptors. To determine if expression of trkB and/or trkC striatal mRNAs is also regulated by the integrity of the dopaminergic afferents, adult rats were given unilateral injections of 6-hydroxydopamine (6-OHDA), a selective catecholamine neurotoxin, or vehicle into the right ascending medial forebrain bundle. Following a 2 week survival period, in situ hybridization with 35S-labelled cRNA probes for the kinase-specific, full-length form of trkB mRNA and all forms of trkC mRNA was performed in striatal sections. A significant increase in the hybridization density for trkB mRNA was observed in the caudate-putamen ipsilateral to the 6-OHDA injection, compared with the uninjected control side (P < 0.001). In contrast, no alteration in the hybridization density for trkC mRNA was observed in the striatum of 6-OHDA-treated rats. No alterations in trkB or trkC mRNA levels were observed in the striata of vehicle-treated animals. These data suggest that midbrain dopaminergic afferents regulate the expression of trkB mRNA in the caudate-putamen. Alternatively, since dopaminergic neurons of the ventral mesencephalon express BDNF mRNA, the up-regulation of striatal trkB mRNA may reflect a compensatory response by striatal neurons due to a loss of anterogradely and/or retrogradely derived trophic support from the ventral midbrain.

Neonatal destruction of the dopaminergic nigrostriatal system with the specific neurotoxin 6-hydroxydopamine (6-OHDA) leads to increases in several components of the adult serotonergic raphe-striatal system. Although results following similar lesions of adult ventral midbrain dopaminergic neurons are less consistent, increases in striatal serotonin (5-hydroxytryptamine; 5HT) fiber density, content, and metabolites have been reported. The effect of such lesions upon gene expression for striatal 5HT receptors, however, has not been determined. The purpose of the present study was to investigate possible changes in expression of several 5HT receptor mRNAs in rat striatum following destruction of the adult nigrostriatal pathway. In situ hybridization for 5HT1A, 5HT1C, and 5HT2 receptor subtype mRNAs was performed in rat striatum following unilateral injection of 6-OHDA into the medial forebrain bundle or directly into the ventral midbrain. Compared to the uninjected control side, a significant increase in the hybridization density for 5HT2 receptor mRNA was observed in the caudate-putamen ipsilateral to the 6-OHDA lesion (P < 0.05). In contrast, no significant changes in the hybridization densities for 5HT1A or 5HT1C receptor mRNAs were detected. The observed increase in striatal 5HT2 receptor mRNA levels after the dopamine-depleting lesion provides evidence for plasticity of the serotonergic raphe-striatal system in the adult rat at the level of striatal gene expression. Furthermore, the present data indicate that dopaminergic mechanisms differentially regulate the expression of 5HT receptor mRNAs in adult rat striatum.

In situ hybridization with a cRNA probe was used to determine the cellular expression of mRNA for the epidermal growth factor receptor (EGF-R) within the rat dopaminergic nigrostriatal system. Hybridization for EGF-R mRNA was distributed throughout the ventral mesencephalon within cells of the substantia nigra pars compacta and ventral tegmental area (VTA). Unilateral lesion of the nigrostriatal pathway with the neurotoxin 6-hydroxydopamine resulted in substantial elimination of EGF-R cRNA hybridization in the ipsilateral substantia nigra and VTA. EGF-R mRNA was also demonstrated within a population of striatal somata, with highest levels of expression detected neonatally. These results indicate that a subpopulation of ventral midbrain dopaminergic neurons, as well as striatal perikarya, express the EGF-R and, thus, may be directly responsive to endogenous EGF, transforming growth factor-alpha, or another EGF-R ligand in vivo.