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Presence of viremia during febrile neutropenic episodes in patients undergoing chemotherapy for malignant neoplasms. Am J Hematol 2021; 96:719-726. [PMID: 33784434 DOI: 10.1002/ajh.26177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 12/17/2022]
Abstract
The importance of viral infections as a leading cause of morbidity and mortality is well documented in severely immunosuppressed patients undergoing allogeneic stem cell transplantation. By contrast, viral infections generally receive less attention in patients with malignant disorders undergoing chemotherapy, where the onset of neutropenic fever is mostly associated with bacterial or fungal infections, and screening for viral infections is not routinely performed. To address the occurrence of invasive viral infections in a clinical setting commonly associated with less pronounced immunosuppression, we have prospectively screened 237 febrile neutropenic episodes in pediatric (n = 77) and adult (n = 69) patients undergoing intensive chemotherapy, primarily for treatment of acute leukemia. Serial peripheral blood specimens were tested by RQ-PCR assays for the presence and quantity of the clinically relevant viruses CMV, EBV, HHV6 and HAdV, commonly reactivated in highly immunocompromised patients. Viremia was documented in 36 (15%) episodes investigated, including the detection of HHV6 (n = 14), EBV (n = 15), CMV (n = 6), or HAdV (n = 1). While low or intermediate levels of viremia (<104 virus copies/mL) were commonly associated with bacterial or fungal co-infection, viremia at higher levels (>104 copies/mL) was documented in patients without evidence for other infections, raising the possibility that at least in some instances the onset of fever may have been attributable to the virus detected. The observations suggest that viral infections, potentially resulting from reactivation, might also play a clinically relevant role in patients receiving chemotherapy for treatment of malignant neoplasms, and routine screening for viremia in this clinical setting might be warranted.
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AmAMP1 from Acropora millepora and damicornin define a family of coral-specific antimicrobial peptides related to the Shk toxins of sea anemones. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 114:103866. [PMID: 32937163 DOI: 10.1016/j.dci.2020.103866] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/07/2020] [Accepted: 09/08/2020] [Indexed: 06/11/2023]
Abstract
A candidate antimicrobial peptide (AmAMP1) was identified by searching the whole genome sequence of Acropora millepora for short (<125AA) cysteine-rich predicted proteins with an N-terminal signal peptide but lacking clear homologs in the SwissProt database. It resembled but was not closely related to damicornin, the only other known AMP from a coral, and was shown to be active against both Gram-negative and Gram-positive bacteria. These proteins define a family of AMPs present in corals and their close relatives, the Corallimorpharia, and are synthesised as preproproteins in which the C-terminal mature peptide contains a conserved arrangement of six cysteine residues. Consistent with the idea of a common origin for AMPs and toxins, this Cys motif is shared between the coral AMPs and the Shk neurotoxins of sea anemones. AmAMP1 is expressed at late stages of coral development, in ectodermal cells that resemble the "ganglion neurons" of Hydra, in which it has recently been demonstrated that a distinct AMP known as NDA-1 is expressed.
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3
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Risk factors for early onset prosthetic valve endocarditis: a case–control study. J Hosp Infect 2018; 100:437-443. [DOI: 10.1016/j.jhin.2018.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 07/10/2018] [Indexed: 10/28/2022]
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4
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Intra-muscular haemangioma of the masseter: A clinical update and differential diagnosis of a rare entity. JOURNAL OF STOMATOLOGY, ORAL AND MAXILLOFACIAL SURGERY 2018; 119:510-513. [PMID: 29883629 DOI: 10.1016/j.jormas.2018.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 04/07/2018] [Accepted: 05/29/2018] [Indexed: 10/14/2022]
Abstract
The intramuscular haemangioma (IMH) is a rare variant of unknown aetiology and comprises 0.8% of soft tissue haemangiomas. Less than 20% of IMHs occur in the craniofacial region of which the masseter is the most common site. It presents as a non-specific, painful soft tissue enlargement in young adults. Symptoms common to vascular lesions usually are absent. Due to the paucity of clinical symptoms, advanced imaging techniques like MRIs are needed to clinch a definitive pre-operative diagnosis. The therapeutic modalities mentioned in the literature range from total surgical excision to non-surgical methods like cryotherapy, sclerotherapy, embolization and feeder vessel ligation. We present a case of an intra-massetric IMH in a 16-year-old male which was treated by total surgical excision with a follow up of 3 years. We also stress on the differential diagnosis of intra-massetric lesions and the key findings of the various imaging modalities available for IMH.
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Blasted copper slag as fine aggregate in Portland cement concrete. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 196:607-613. [PMID: 28355593 DOI: 10.1016/j.jenvman.2017.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 02/08/2017] [Accepted: 03/12/2017] [Indexed: 06/06/2023]
Abstract
The present work focuses on assessing the viability of applying blasted copper slag, produced during abrasive blasting, as fine aggregate for Portland cement concrete manufacturing, resulting in an alternative and safe disposal method. Leaching assays showed no toxicity for this material. Concrete mixtures were produced, with high aggregate replacement ratios, varying from 0% to 100%. Axial compressive strength, diametrical compressive strength, elastic modulus, physical indexes and durability were evaluated. Assays showed a significant improvement in workability, with the increase in substitution of fine aggregate. With 80% of replacement, the concrete presented lower levels of water absorption capacity. Axial compressive strength and diametrical compressive strength decreased, with the increase of residue replacement content. The greatest reductions of compressive strength were found when the replacement was over 40%. For tensile strength by diametrical compression, the greatest reduction occurred for the concrete with 80% of replacement. After the accelerated aging, results of mechanic properties showed a small reduction of the concrete with blasted copper slag performance, when compared with the reference mixture. Results indicated that the blasted copper slag is a technically viable material for application as fine aggregate for concrete mixtures.
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FRI0600 Fears and Beliefs of People Living with Rheumatoid Arthritis, Ankylosing Spondylitis or Psoriatic Arthritis: A Systematic Literature Review. Ann Rheum Dis 2016. [DOI: 10.1136/annrheumdis-2016-eular.2204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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AB0505 Case report of allogeneic unrelated-donor mesenchymal stem cells (msc) infusion in systemic sclerosis (ssc). Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2013-eular.2827] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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8
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[Hibernoma and cervical rib: two rare diseases, the same manifestation]. CIRUGIA PEDIATRICA : ORGANO OFICIAL DE LA SOCIEDAD ESPANOLA DE CIRUGIA PEDIATRICA 2013; 26:138-141. [PMID: 24482907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The hibernoma is a rare benign tumor of soft tissue, derived from remnants of fetal brown adipose tissue. A cervical rib is a supernumerary or accessory rib derived from the 7th cervical vertebra. CLINCAL CASE: 2-year-old girl, previously healthy, referenced to Pediatrics consultation, for left supraclavicular mass. No history of infectious diseases or systemic symptoms. At exam presented mass in supraclavicular left region, 1.5 to 2 cm in diameter, hard, mobile, non-adherent to the deep planes. Laboratory tests exclude an infectious or lymphoproliferative disease. In cervical radiograph we observed bilateral cervical ribs. Cervical ultrasound revealed calcified nodule 0.8 cm, compatible with calcified adenopathy. Biopsy was performed and histology revealed a hibernoma, which was completely removed surgically. This case illustrates the association of two diagnoses, uncommon in children. These were made during the investigation of lymphadenopathies, a frequent reason for pediatrics consultation.
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Meteorin is a chemokinetic factor in neuroblast migration and promotes stroke-induced striatal neurogenesis. J Cereb Blood Flow Metab 2012; 32:387-98. [PMID: 22044868 PMCID: PMC3272610 DOI: 10.1038/jcbfm.2011.156] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 08/24/2011] [Accepted: 09/22/2011] [Indexed: 12/19/2022]
Abstract
Ischemic stroke affecting the adult brain causes increased progenitor proliferation in the subventricular zone (SVZ) and generation of neuroblasts, which migrate into the damaged striatum and differentiate to mature neurons. Meteorin (METRN), a newly discovered neurotrophic factor, is highly expressed in neural progenitor cells and immature neurons during development, suggesting that it may be involved in neurogenesis. Here, we show that METRN promotes migration of neuroblasts from SVZ explants of postnatal rats and stroke-subjected adult rats via a chemokinetic mechanism, and reduces N-methyl-D-asparate-induced apoptotic cell death in SVZ cells in vitro. Stroke induced by middle cerebral artery occlusion upregulates the expression of endogenous METRN in cells with neuronal phenotype in striatum. Recombinant METRN infused into the stroke-damaged brain stimulates cell proliferation in SVZ, promotes neuroblast migration, and increases the number of immature and mature neurons in the ischemic striatum. Our findings identify METRN as a new factor promoting neurogenesis both in vitro and in vivo by multiple mechanisms. Further work will be needed to translate METRN's actions on endogenous neurogenesis into improved recovery after stroke.
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Cometin is a novel neurotrophic factor that promotes neurite outgrowth and neuroblast migration in vitro and supports survival of spiral ganglion neurons in vivo. Exp Neurol 2011; 233:172-81. [PMID: 21985865 DOI: 10.1016/j.expneurol.2011.09.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 08/31/2011] [Accepted: 09/20/2011] [Indexed: 12/22/2022]
Abstract
Neurotrophic factors are secreted proteins responsible for migration, growth and survival of neurons during development, and for maintenance and plasticity of adult neurons. Here we present a novel secreted protein named Cometin which together with Meteorin defines a new evolutionary conserved protein family. During early mouse development, Cometin is found exclusively in the floor plate and from E13.5 also in dorsal root ganglions and inner ear but apparently not in the adult nervous system. In vitro, Cometin promotes neurite outgrowth from dorsal root ganglion cells which can be blocked by inhibition of the Janus or MEK kinases. In this assay, additive effects of Cometin and Meteorin are observed indicating separate receptors. Furthermore, Cometin supports migration of neuroblasts from subventricular zone explants to the same extend as stromal cell derived factor 1a. Given the neurotrophic properties in vitro, combined with the restricted inner ear expression during development, we further investigated Cometin in relation to deafness. In neomycin deafened guinea pigs, two weeks intracochlear infusion of recombinant Cometin supports spiral ganglion neuron survival and function. In contrast to the control group receiving artificial perilymph, Cometin treated animals retain normal electrically-evoked brainstem response which is maintained several weeks after treatment cessation. Neuroprotection is also evident from stereological analysis of the spiral ganglion. Altogether, these studies show that Cometin is a potent new neurotrophic factor with therapeutic potential.
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Thrombospondin-1 binds to ApoER2 and VLDL receptor and functions in postnatal neuronal migration. EMBO J 2008; 27:3069-80. [PMID: 18946489 DOI: 10.1038/emboj.2008.223] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Accepted: 09/26/2008] [Indexed: 11/09/2022] Open
Abstract
Apolipoprotein E receptor 2 (ApoER2), very low-density lipoprotein receptor (VLDLR), and Dab1 are the main components of the Reelin signalling cascade. Reelin is the sole ligand defined so far in signalling through this pathway. Postnatal migration of neuronal precursors from the subventricular zone (SVZ) to the olfactory bulb (OB), however, depends on ApoER2 and Dab1, but functions independently of Reelin. Here, we show that thrombospondin-1 (THBS-1) is a novel physiological ligand for ApoER2 and VLDLR. THBS-1 is present in the SVZ and along the entire rostral migratory stream (RMS). It binds to ApoER2 and VLDLR and induces phosphorylation of Dab1. In contrast to Reelin, it does not induce Dab1 degradation or Akt phosphorylation, but stabilizes neuronal precursor chains derived from subventricular explants. Lack of THBS-1 results in anatomical abnormalities of the RMS and leads to a reduction of postnatal neuronal precursors entering the OB.
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[Loco-regional anesthesia in vascular surgery]. REVISTA PORTUGUESA DE CIRURGIA CARDIO-TORACICA E VASCULAR : ORGAO OFICIAL DA SOCIEDADE PORTUGUESA DE CIRURGIA CARDIO-TORACICA E VASCULAR 2008; 15:211-215. [PMID: 19305881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Per-operative management of patients with cardiovascular pathology, has been regarded, since ever, as a challenge for anesthesiologists and vascular surgeons. Vascular disease, often diffuse and asymptomatic, has a high prevalence in the community and is associated to an annual mortality rate of 12%. This requires that anesthetic technique should be concentrated in the preservation of myocardial, renal, pulmonary and cerebral functions, during the hemodynamic alterations related to surgery, in order to lower the per-operative complications and to promote faster and safer post-operative recovery. In this paper we describe the experience of the Anesthesiology Department of S. Joatilde;o Hospital, Porto, particulary with the superficial and deep cervical plexus block, in carotid endarterectomy surgery.
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478. Hemodynamic Instability During Carotid Endarterectomy: General Anesthesia vs Cervical Plexus Block. Reg Anesth Pain Med 2008. [DOI: 10.1136/rapm-00115550-200809001-00157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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14
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472. Regional Block Anaesthesia vs General Anaesthesia for Carotid Endarterectomy. Reg Anesth Pain Med 2008. [DOI: 10.1136/rapm-00115550-200809001-00128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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PO4-102 ISOFORM-SPECIFIC INTERFERENCE OF APOE WITH THE REELIN SIGNALING PATHWAY. ATHEROSCLEROSIS SUPP 2007. [DOI: 10.1016/s1567-5688(07)71112-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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ApoER2/VLDL receptor and Dab1 in the rostral migratory stream function in postnatal neuronal migration independently of Reelin. Proc Natl Acad Sci U S A 2007; 104:8508-13. [PMID: 17494763 PMCID: PMC1895980 DOI: 10.1073/pnas.0611391104] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Postnatal migration of interneuron precursors from the subventricular zone to the olfactory bulb occurs in chains that form the substrate for the rostral migratory stream. Reelin is suggested to induce detachment of neuroblasts from the chains when they arrive at the olfactory bulb. Here we show that ApoER2 and possibly very-low-density lipoprotein receptor (VLDLR) and their intracellular adapter protein Dab1 are involved in chain formation most likely independent of Reelin. F-spondin, which is present in the stream, may act as ligand for ApoER2 and VLDLR. In mice lacking either both receptors or Dab1 chain formation is severely compromised, and as a consequence the rostral migratory stream is virtually absent and neuroblasts accumulate in the subventricular zone. The mutant animals exhibit severe neuroanatomical defects in the subventricular zone and in the olfactory bulb. These data demonstrate a cell-autonomous function of ApoER2, and most likely VLDLR and Dab1, in postnatal migration of neuroblasts in the forebrain, which is suggested to depend on ligands other than Reelin.
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Factor structure of the CES-D (Center for Epidemiologic Studies Depression Scale) among Filipino-American adolescents. Soc Psychiatry Psychiatr Epidemiol 1999; 34:211-5. [PMID: 10365627 DOI: 10.1007/s001270050135] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The present study used factor analytic procedures to examine the factor structure of the CES-D among Filipino-American adolescents residing in rural and small town Hawaii. A total of 243 Filipino-American high school students completed the 20-item scale, and maximum likelihood analyses were employed to obtain a final solution. The results indicated that two factors provide a reasonably good fit: factor I combined depressed affect, somatic-retardation and interpersonal items, and factor II consisted of the remaining four positive affect items. The overlap of depressed affect and somatic symptoms support previous findings found among Asian American adults and other ethnic minority adolescents. The loading of the interpersonal items on the first factor is more unusual and suggests that interpersonal factors are not distinguished from depressed affect for the Filipino-American adolescent group. The usefulness of the CES-D as a tool to gain an understanding of the concept of depression across cultures is discussed.
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Abstract
The purpose of this work was to determine the hormone dependence of mammary tumors induced in Sprague-Dawley rats by three intraperitoneal injections of N-nitroso-N-methylurea at 50, 80, and 110 days of age. Two experimental designs were carried out: (a) Ten days before the first NMU injection, 130 rats were divided into 13 batches and randomly assigned to the following treatments: control, ovariectomy (OVX), tamoxifen (TAM), bromocriptine (BROM), haloperidol (HAL), estradiol (E2), progesterone (Pg), OVX + BROM, TAM + BROM, OVX + HAL, TAM + HAL, OVX + TAM, and E2 + BROM. After 150 days of treatment the following growth parameters were determined: latency period (LP), mean tumor number per rat (n/t), and tumor incidence (TI). LP was significantly increased (p < 0.05) only by Pg and TAM + BROM. The n/t was significantly decreased (p < 0.05) by all treatments except HAL. TI was significantly reduced by OVX, TAM, BROM, and their combinations, (b) Rats bearing ip-NMU-induced mammary tumors were divided into 7 batches and assigned to the following treatments: control, OVX, TAM, BROM, HAL, OVX + BROM, and TAM + BROM. Tumor growth was assessed up to 60 days of treatment; only OVX, TAM and their combination with BROM were able to produce tumor regression. These results support the essential role of E2 and prolactin in the promotion stage of carcinogenesis. However, for established tumors, growth becomes more independent from hormone influence, in particular from prolactin deprivation. We conclude that this model seems suitable for studying the mechanisms underlying the evasion of hormonal control of tumor growth.
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Abstract
The Ross operation is physiologically the best approach for aortic valve replacement. At the Hospital de Santa Cruz 22 consecutive pulmonary autograft operations have been performed in patients with a mean age of 49 (range 17-65) years. Six patients had mitral valve disease, two had aortic aneurysms and one had a ventricular septal defect. Subcoronary implantation of the autograft was performed in 20 patients. A partial inclusion aortic root replacement technique was used in one and the aortic root was replaced in another. There were no hospital or late deaths. Two patients required autograft replacement at 3 and 9 months postoperatively because of regurgitation. One of these cases was caused by an abnormality of the pulmonary valve and since then echocardiographic assessments of this valve have been performed routinely and have detected significant pulmonary incompetence in four patients who otherwise would have been operated on using the Ross procedure.
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The rate and characteristics of suicide attempters in the native Hawaiian adolescent population. Suicide Life Threat Behav 1996; 26:27-36. [PMID: 9173607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Native Hawaiian high school students, N = 1779, were surveyed for symptoms of psychopathology and suicide attempts in the previous 6 months. Seventy-seven (4.3%) of the students reported making a suicide attempt. There were no significant differences in prevalence rates for males and females. Depression, anxiety, aggression, substance abuse symptoms, and low family support, but not peer support, were significantly correlated with suicide attempts. On logistic regression, depression, substance abuse, and family support independently predicted attempts. The lack of gender difference may indicate a cultural characteristic of the Hawaiian population that differentiates it from mainstream American populations but likens it to the Native American population.
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Abstract
Mammary adenocarcinomas induces in female Sprague-Dawley rats by three intraperitoneal injections of N-nitroso-N-methylurea were studied in order to characterize their estrogen (ER), progesterone (PgR), prolactin (PRLR) and epidermal growth factor (EGFR) receptors. All samples evaluated showed the presence of ER and PgR in the cytosol fraction and PRLR amd EGFR in the membrane fraction. Q (fmol/mg) and K(d) (nM) values were as follows: ER, 56 +/- 11 and 0.5 +/- 0.1; PgR, 109 +/- 25 and 2.2 +/- 0.5 and PRLR, 335 +/- 75 and 0.5 +/- 0.2, respectively. In all tumors studied, two specific sites were found for EGFR, one with Q(1) = 22 +/- 9 and K(d1) = 0.6 +/- 0.3, and the other with Q(2) = 125 +/- 33 and K(d2) = 2.1 +/- 0.5. Receptor content was found to be independent of tumor histopathological variety. Displacement index (DI) with estradiol and tamoxifen of [I(3)H]E2-ER binding showed great heterogeneity, with values ranging from 0.01 to1.54. No correlation between ER content and DI values was found. Antiestrogenic binding sites were not found in the microsomal fraction of ten mammary tumors examined. Proliferation of this experimental mammary tumor may be regulated by a complex interaction of steroid and polypeptide hormones, as well as growth factors.
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MESH Headings
- Animals
- Carcinogens
- Carcinoma, Ductal, Breast/chemically induced
- Carcinoma, Ductal, Breast/chemistry
- ErbB Receptors/analysis
- Female
- Mammary Neoplasms, Experimental/chemically induced
- Mammary Neoplasms, Experimental/chemistry
- Methylnitrosourea
- Rats
- Rats, Sprague-Dawley
- Receptors, Estrogen/analysis
- Receptors, Progesterone/analysis
- Receptors, Prolactin/analysis
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Abstract
The effect of tamoxifen (TAM) was evaluated on a mammary tumor model induced in Sprague-Dawley rats by intraperitoneal administration of three N-nitroso-N-methylurea (NMU) doses. Animals received TAM (1 mg/kg per day) from 10 days before the first NMU dose up to 140 days later. Thereafter, treatment was discontinued and the observation period was extended 60 days longer. Mean overall latency period, tumor number per rat and tumor incidence were recorded. Significant differences between treated and control batches were observed in tumor number per rat (1.8 +/- 1.1 versus 5.2 +/- 1.6; P < 0.05) and in tumor incidence (50% versus 100%; P < 0.05), respectively. No significant difference in latency period between both batches was recorded. All lesions induced in the control batch were malignant, whereas only 45% of those induced in TAM-treated animals were malignant and the remaining 55% were preneoplastic. At 60 days after treatment discontinuance, tumor incidence increased to 90% and also tumor number per rat increased to 4.6 +/- 1.5. TAM effect was also evaluated in rats with NMU-induced tumors by treatment with 1 mg/kg per day during 60 days starting when tumors reached a 1.5-cm diameter. Regression to less than 80% of initial size in 49% of the tumors was observed, while in ovariectomized rats, 33% of tumors regressed. Estrogen receptor content, ER (fmol/mg protein) and Kd (nM) in control tumors were: 56 +/- 10 and 0.5 +/- 0.1. In tumors of TAM-treated animals, ER was less than 5 fmol/mg protein. Findings demonstrate that TAM significantly decreased the appearance of tumors induced in rats by i.p. injection of NMU and when TAM treatment was initiated after tumor induction, some tumors failed to respond to hormonal manipulation. Differential tumor growth response after TAM or oophorectomy in each tumor indicates that in the same rat it is possible to distinguish hormone-dependent and hormone-autonomous tumor populations. Hormonal regulation of tumor growth can be under intrinsic control, regardless of the hormonal status of the whole organism.
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Induction of mammary tumors in rat by intraperitoneal injection of NMU: histopathology and estral cycle influence. Cancer Lett 1994; 86:223-8. [PMID: 7982211 DOI: 10.1016/0304-3835(94)90082-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In order to obtain an experimental model we induced mammary tumors in female Sprague-Dawley rats. The carcinogen N-nitroso-N-methylurea (NMU) was injected intraperitoneally (i.p.) at doses of 50 mg/kg body weight when animals were 50, 80 and 110 days old. Tumor sizes were measured with a caliper and their growth parameters and histopathological properties were tested. For 100 rats, 88.4% of developed lesions were ductal carcinomas, histologically classified as 52.8% cribiform variety, 30.6% solid carcinoma. Metastases in liver, spleen and lung were present. Other primary tumors were detected with low incidence. The influence of the rat estrous cycle during the first exposure to intraperitoneal NMU injection was studied. The latency period in estrus, proestrus and diestrus was 82 +/- 15, 77 +/- 18 and 79 +/- 18 days, respectively. Tumor incidence was significantly higher in estrus (95.2%) than proestrus (71.4%) or diestrus (77.4), (P < 0.01). Mean number or tumors per animal was similar among the three groups (4.4 +/- 3.2, 3.8 +/- 3.6, 3.2 +/- 1.8). The procedure described appears to be the simplest method for inducing experimental mammary tumors in rats.
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[Honduras: teaching and institutional human resources development through continuing education]. EDUCACION MEDICA Y SALUD 1994; 28:301-9. [PMID: 7925090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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The incidence of intestinal parasites in some Hilo Hospital patients. HAWAII MEDICAL JOURNAL 1977; 36:172-3. [PMID: 873788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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[Primary penile sarcoma]. REVISTA ARGENTINA DE UROLOGIA Y NEFROLOGIA 1969; 38:66-8. [PMID: 5372436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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