ABSTRACT
Correctional staff are a necessary and valuable resource for correctional institutions, in both Western and Nonwestern nations; however, studies of correctional staff in Nonwestern nations, particularly those in Africa, are lacking. Improving the job satisfaction and organizational commitment of these staff are imperative, as both of these job attitudes have been linked to many salient beneficial outcomes. Most of the existing empirical research on correctional staff organizational justice explores only the effects of procedural and distributive justice and ignores interpersonal justice. Additionally, there has been little research on how procedural, distributive, and interpersonal justice affect correctional staff in Nonwestern correctional organizations. The current study explored the effects of all three forms of organizational justice on the job satisfaction and organizational commitment of staff at a medium security prison in southeast Nigeria. Based on Ordinary Least Squares (OLS) regression, all three forms of justice had significant positive effects on commitment. Procedural and interpersonal justice had positive effects on job satisfaction, while distributive justice had nonsignificant effects. Correctional administrators need to be aware the importance of procedural, distributive, and interpersonal justice and attempt to improve perceptions of these organizational justice variables.
Subject(s)
Job Satisfaction , Organizational Culture , Humans , Nigeria , Social Justice , Surveys and QuestionnairesABSTRACT
BACKGROUND: Several studies have shown that fluconazole prophylaxis reduces the risk of fungal colonization and of invasive fungal infection in high-risk patients with minimal toxicity. This systematic review was designed to estimate the risk of emergence of colonization and infection either with azole susceptible-dose dependent or with resistant strains. METHODS: We searched Medline, EMBASE, the Cochrane Collaboration database and our own files for randomized controlled trials assessing the effect of fluconazole on the incidence of fluconazole-resistant strains. RESULTS: This systematic review of randomized clinical trials shows that fluconazole prophylaxis increases the risk for colonization with fluconazole susceptible-dose dependent or with resistant yeasts, the percentage of non-albicans Candida isolates and the percentage of fluconazole susceptible-dose dependent or resistant fungal isolates. Fluconazole prophylaxis did not significantly affect the risk of invasive disease with fluconazole susceptible-dose dependent or resistant fungi. The sample size was too small to assess the effect of fluconazole prophylaxis on the risk for breakthrough infections with non-albicans Candida. CONCLUSION: Evidence from randomized trials suggests that fluconazole prophylaxis increases the risk for colonization with fluconazole susceptible-dose dependent or with resistant fungi, but does not significantly affect the risk for invasive infections with fluconazole susceptible-dose dependent or with resistant fungi. The risk for breakthrough infections remains a concern and needs to be addressed in large prospective studies.
Subject(s)
Antifungal Agents/therapeutic use , Drug Resistance, Fungal , Fluconazole/therapeutic use , Candidiasis/drug therapy , Candidiasis/microbiology , Evidence-Based Medicine , Humans , Risk FactorsABSTRACT
BACKGROUND AND OBJECTIVES: Many phenotypic variations in the expression of blood group A have been explained by variations in gene structure, but unresolved samples are frequently encountered in the reference laboratory. Among ABO subgroups, A(bantu) has the highest frequency in a specified population. The molecular basis of this phenotype is now described. MATERIALS AND METHODS: Blood from Black donors phenotyped as A(bantu) was subjected to genomic ABO screening and direct sequencing of polymerase chain reaction (PCR)-amplified ABO exons 1-7 and introns 2-6. Total RNA was extracted and ABO cDNA was synthesized by reverse transcription (RT)-PCR. Control material comprised Black South African, Swedish, Jordanian and Brazilian blood samples with common phenotypes. RESULTS: Genomic ABO typing indicated the presence of an A(2) allele in each A(bantu) donor, in combination with an O allele. No previously reported mutations associated with weak A or B expression were found. Direct sequencing indicated the common A(2) sequence with a single nucleotide deletion (AGGT>AGT) at the exon 4/intron 4 junction, predicted either to disrupt the reading frame (resulting in a premature stop codon) or to cause erroneous splicing (resulting in the exclusion of exon 4 from the mRNA). O mRNA, but no transcripts from the A(bantu) allele, could be detected. Surprisingly, the splice-site mutation was also found in approximately 5% of O alleles in Black South Africans, but not in other blood donors, or in non-O(1) alleles. Utilizing intron polymorphisms, the A(bantu) allele was shown to be a recombination between a new allelic lineage (O(1bantu)) and A(2), with a cross-over region near exon 5. CONCLUSION: The A(bantu) phenotype is caused by an O(1bantu)-A(2) hybrid at the ABO locus.
Subject(s)
ABO Blood-Group System/genetics , Alleles , Black People/genetics , Mutation , RNA Splice Sites/genetics , Recombination, Genetic , Ethnicity/genetics , Exons , Frameshift Mutation , Gene Frequency , Genetic Testing , Humans , Introns , Phenotype , RNA, Messenger/geneticsABSTRACT
Cores for teeth with vital pulps is the seventh in the series of crowns and other extra-coronal restorations. A core is defined as 'that part of a preparation for an indirect restoration consisting of restorative material'. This article questions the need for routine pin placement and addresses the following issues--removal of existing restorations, the need for a core, core materials, core retention, and problem solving.
Subject(s)
Crowns , Dental Pins , Dental Prosthesis Design , Composite Resins/chemistry , Dental Amalgam/chemistry , Dental Bonding , Dental Cements/chemistry , Dental Materials/chemistry , Dental Prosthesis Retention , Dental Restoration Failure , Glass Ionomer Cements/chemistry , Humans , Matrix Bands , Problem Solving , Resin Cements/chemistry , Retreatment , Tooth Fractures/etiology , Tooth Preparation, Prosthodontic/instrumentation , Tooth Preparation, Prosthodontic/methodsABSTRACT
The purine nucleoside adenosine exerts numerous effects in the mammalian heart, the most well-recognized being regulation of coronary blood flow and cardiac conduction. These effects are mediated via activation of G protein linked adenosine receptor subtypes, A(2a) and A(1) receptors, located primarily on vascular cells and cardiac myocytes, respectively. Although adenosine A(1) receptors are also expressed in ventricular myocytes, adenosine exerts no significant direct effects in these cells. A recent report from our laboratory indicates that ventricular myocyte A(1) receptors are concentrated in caveolin enriched plasma membrane microdomains referred to as caveolae. This review focuses on these recent findings and their relevance to subcellular compartmentalization of A(1) receptor signaling in ventricular myocardium.
Subject(s)
Caveolae/metabolism , Myocardial Ischemia/metabolism , Myocardium/metabolism , Myocardium/pathology , Receptors, Purinergic P1/metabolism , Animals , Cell Compartmentation/physiology , Humans , Rabbits , Rats , Signal Transduction/physiologyABSTRACT
The class B, type I scavenger receptor (SR-BI) mediates the selective uptake of high density lipoprotein (HDL) cholesteryl esters and the efflux of free cholesterol. SR-BI is predominantly associated with caveolae in Chinese hamster ovary cells. The caveola protein, caveolin-1, binds to cholesterol and is involved in intracellular cholesterol trafficking. We previously demonstrated a correlative increase in caveolin-1 expression and the selective uptake of HDL cholesteryl esters in phorbol ester-induced differentiated THP-1 cells. The goal of the present study was to determine if the expression of caveolin-1 is the causative factor in increasing selective cholesteryl ester uptake in macrophages. To test this, we established RAW and J-774 cell lines that stably expressed caveolin-1. Transfection with caveolin-1 cDNA did not alter the amount of 125I-labeled HDL that associated with the cells, although selective uptake of HDL [3H]cholesteryl ether was decreased by approximately 50%. The amount of [3H]cholesterol effluxed to HDL was not affected by caveolin-1. To directly address whether caveolin-1 inhibits SR-BI-dependent selective cholesteryl ester uptake, we overexpressed caveolin-1 by adenoviral vector gene transfer in Chinese hamster ovary cells stably transfected with SR-BI. Caveolin-1 inhibited the selective uptake of HDL [3H]cholesteryl ether by 50-60% of control values without altering the extent of cell associated HDL. We next used blocking antibodies to CD36 and SR-BI to demonstrate that the increase in selective [3H]cholesteryl ether uptake previously seen in differentiated THP-1 cells was independent of SR-BI. Finally, we used beta-cyclodextrin and caveolin overexpression to demonstrate that caveolae depleted of cholesterol facilitate SR-BI-dependent selective cholesteryl ester uptake and caveolae containing excess cholesterol inhibit uptake. We conclude that caveolin-1 is a novel negative regulator of SR-BI-dependent selective cholesteryl ester uptake.
Subject(s)
CD36 Antigens/metabolism , Caveolins/metabolism , Cholesterol/pharmacokinetics , Lipoproteins, HDL/metabolism , Membrane Proteins , Receptors, Immunologic , Animals , Antibodies/pharmacology , CD36 Antigens/immunology , CHO Cells , Caveolae/drug effects , Caveolae/metabolism , Caveolin 1 , Caveolins/genetics , Cell Differentiation/drug effects , Cells, Cultured , Cricetinae , Esters/pharmacokinetics , Humans , Macrophages/cytology , Macrophages/drug effects , Macrophages/metabolism , Mice , Receptors, Lipoprotein/metabolism , Receptors, Scavenger , Scavenger Receptors, Class B , Tetradecanoylphorbol Acetate/pharmacology , TransfectionABSTRACT
Caveolin-1 traffics cholesterol between the endoplasmic reticulum and cell surface caveolae in a non-vesicle chaperone complex which contains heat shock protein 56, cyclophilin 40, and cyclophilin A. Recent studies demonstrate that endothelial nitric oxide synthase (eNOS), caveolin, hetero-trimeric G-protein coupled receptors, and a calcium channel form an activation complex that is associated with cholesterol-rich caveolae. Oxidized LDL depletes caveolae of cholesterol and prevents agonist stimulation of eNOS by disrupting the activation complex. HDL antagonizes the effects of oxLDL by donating cholesterol to caveolae, thereby preserving the structure and function of caveolae. These findings and others provide a possible mechanistic basis for some of the molecular changes observed in vascular disease.
Subject(s)
Caveolins/pharmacology , Cholesterol/pharmacology , Lipoproteins/pharmacology , Nitric Oxide Synthase/metabolism , Vascular Diseases/metabolism , Caveolin 1 , Humans , Nitric Oxide Synthase Type III , Receptors, Lipoprotein/metabolismABSTRACT
Caveolae can mediate endocytosis, transcytosis, and potocytosis. Our understanding of these processes as well as the elucidation of the molecular machinery involved has greatly expanded. In addition, caveolin, a 22 kDa protein often associated with caveolae, can promote the trafficking of sterol through the cytoplasm independent of vesicles. Caveolin also influences the formation, morphology, and function of caveolae. The ability of caveolae and caveolin to mediate macromolecular transport directly impacts a variety of physiological and pathophysiological processes.
Subject(s)
Caveolae/physiology , Caveolins/physiology , Animals , Biological Transport, Active/physiology , Endocytosis/physiology , HumansABSTRACT
The scavenger receptor class B type I (SR-BI) binds to HDL and mediates the selective uptake of cholesterol esters from HDL to cells. SR-BII is an alternatively spliced product of the SR-BI gene that only differs in the C-terminal cytoplasmic domain. Previous studies with male mice demonstrated that SR-BII comprises about 12% of the total SR-BI/SR-BII present in liver. In the current studies we used a liver cell line, HepG2, and a rat estrogen replacement model to examine the effects of estrogen on the expression of SR-BII. HepG2 cells express SR-BI but not SR-BII. SR-BI/SR-BII - blocking antibodies demonstrated that HepG2 cells selectively internalize cholesterol esters in a SR-BI - dependent manner. Incubation of HepG2 cells with 10 pM of 17beta-estradiol for 12 h eliminated the expression of SR-BI and promoted the up-regulation of SR-BII. Radiolabeled HDL-binding studies demonstrated that 17beta-estradiol increased the number of HDL binding sites by 3-fold in HepG2 cells. However, 17beta-estradiol - treated cell internalized approximately 25% less cholesterol ester than vehicle-only-treated cells. The livers obtained from male rats and ovariectomized female rats contained SR-BI and a small amount of SR-BII. In contrast, the livers obtained from intact female rats and ovariectomized female rats receiving estrogen replacement contained SR-BII and a small amount of SR-BI. The amount of SR-BI and SR-BII in adrenal tissue was not affected by any of the experimental treatments. We conclude that estrogen up-regulates SR-BII in HepG2 cells and rat liver.
Subject(s)
CD36 Antigens/genetics , Carcinoma, Hepatocellular/metabolism , Estradiol/pharmacology , Gene Expression Regulation/drug effects , Liver Neoplasms/metabolism , Liver/metabolism , Membrane Proteins , Receptors, Immunologic , Receptors, Lipoprotein , Alternative Splicing , Animals , CD36 Antigens/analysis , CHO Cells , Cholesterol Esters/metabolism , Cricetinae , Female , Lipoproteins, HDL/metabolism , Liver/chemistry , Male , Ovariectomy , Rats , Rats, Sprague-Dawley , Receptors, Scavenger , Scavenger Receptors, Class B , Transfection , Tumor Cells, CulturedSubject(s)
Antigens, Surface/classification , Blood Group Antigens/classification , Erythrocyte Membrane/immunology , Isoantigens/blood , Rh-Hr Blood-Group System/chemistry , Terminology as Topic , Amino Acid Substitution , Antigens, Surface/genetics , Blood Group Antigens/genetics , Carbohydrates/blood , Carbohydrates/immunology , Epitopes/classification , Humans , Rh-Hr Blood-Group System/immunologyABSTRACT
Recently, we have found an allelic deletion of the secretor alpha(1,2)fucosyltransferase (FUT2) gene in individuals with the classical Bombay phenotype of the ABO system. The FUT2 gene consists of two exons separated by an intron that spans approximately 7 kb. The first exon is noncoding, whereas exon 2 contains the complete coding sequence. Since the 5' breakpoint of the deletion has previously been mapped to the single intron of FUT2, we have cloned the junction region of the deletion in a Bombay individual by cassette-mediated polymerase chain reaction. In addition, the region from the 3' untranslated region of FUT2 to the 3' breakpoint sequence has been amplified from a control individual. DNA sequence analysis of this region indicates that the 5' breakpoint is within a free left Alu monomer (FLAM-C) sequence that lies 1.3 kb downstream of exon 1, and that the 3' breakpoint is within a complete Alu element (AluSx) that is positioned 1.5 kb downstream of exon 2. The size of the deletion is estimated to be about 10 kb. There is a 25-bp sequence identity between the reference DNA sequences surrounding the 5' and 3' breakpoints. This demonstrates that an Alu-mediated large gene deletion generated by unequal crossover is responsible for secretor alpha(1,2)fucosyltransferase deficiency in Indian Bombay individuals.
Subject(s)
ABO Blood-Group System/genetics , Alu Elements , Fucosyltransferases/genetics , Gene Deletion , 3' Untranslated Regions , Alleles , Base Sequence , Cloning, Molecular , DNA Mutational Analysis/methods , DNA, Complementary/metabolism , Exons , Genetic Linkage , Humans , Introns , Models, Genetic , Molecular Sequence Data , Phenotype , Physical Chromosome Mapping , Polymerase Chain Reaction , Sequence Homology, Nucleic Acid , Galactoside 2-alpha-L-fucosyltransferaseABSTRACT
We previously demonstrated that a caveolin-chaperone complex transports newly synthesized cholesterol from the endoplasmic reticulum through the cytoplasm to caveolae. Caveolin-1 has a 33-amino acid hydrophobic domain and three sites of palmitoylation in proximity to the hydrophobic domain. In the present study, we hypothesized that palmitoylation of caveolin-1 is necessary for binding of cholesterol, formation of a caveolin-chaperone transport complex, and rapid, direct transport of cholesterol to caveolae. To test this hypothesis, four caveolin-1 constructs were generated that substituted an alanine for a cysteine at position 133, 143, or 156 or all three sites (triple mutant). These mutated caveolins and wild type caveolin-1 were stably expressed in the lymphoid cell line, L1210-JF, which does not express caveolin-1, does not form a caveolin-chaperone complex, and does not transport newly synthesized cholesterol to caveolae. All of the caveolins were expressed and the proteins localized to plasma membrane caveolae. Wild type caveolin-1 and mutant 133 assembled into complete transport complexes and rapidly (10-20 min) transported cholesterol to caveolae. Caveolin mutants 143 and 156 did not assemble into complete transport complexes, weakly associated with cholesterol, and transported small amounts of cholesterol to caveolae. The triple mutant did not assemble into complete transport complexes and did not associate with cholesterol. We conclude that palmitoylation of caveolin-1 at positions 143 and 156 is required for cholesterol binding and transport complex formation.