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1.
Br J Psychol ; 108(3): 544-563, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27620075

ABSTRACT

The concept of learning style is immensely popular despite the lack of evidence showing that learning style influences performance. This study tested the hypothesis that the popularity of learning style is maintained because it is associated with subjective aspects of learning, such as judgements of learning (JOLs). Preference for verbal and visual information was assessed using the revised Verbalizer-Visualizer Questionnaire (VVQ). Then, participants studied a list of word pairs and a list of picture pairs, making JOLs (immediate, delayed, and global) while studying each list. Learning was tested by cued recall. The results showed that higher VVQ verbalizer scores were associated with higher immediate JOLs for words, and higher VVQ visualizer scores were associated with higher immediate JOLs for pictures. There was no association between VVQ scores and recall or JOL accuracy. As predicted, learning style was associated with subjective aspects of learning but not objective aspects of learning.


Subject(s)
Cognition/physiology , Judgment/physiology , Learning/physiology , Acoustic Stimulation , Adolescent , Cues , Female , Humans , Mental Recall/physiology , Photic Stimulation , Surveys and Questionnaires , Time Factors , Young Adult
2.
Prev Med Rep ; 2: 423-8, 2015.
Article in English | MEDLINE | ID: mdl-26844100

ABSTRACT

UNLABELLED: College students engage in many unhealthy behaviors, one of these, heavy alcohol use, is a major global public health problem. OBJECTIVE: This longitudinal study examined whether students' mandated/voluntary status in a program to reduce college drinking was associated with overall health, ethnicity, gender, and personality traits. Both mandated and voluntary groups participated in the Motivational Intervention (MI) program to prevent high risk drinking. METHODS: Freshmen (710 voluntary, 190 mandated, n = 900) between the ages of 18 and 21, received the MI at baseline and again at 2 weeks, with boosters at 3, 6 and 12 months. Participants completed three measures: the Daily Drinking Questionnaire (DDQ); the Substance Use Risk Profile Scale (SURPS), and the Health Promoting Lifestyle Profile II (HPLPII). Mandated and voluntary participants were compared at baseline and following the intervention using two sample t-tests for continuous variables (overall health, personality traits, drinking measures), and chi-square for categorical variables (gender, ethnicity). Linear mixed models were used to identify associations between HPLP II scores and mandated/voluntary status, time, ethnicity gender and SURPS scale scores. RESULTS: In both groups, alcohol consumption dropped significantly by 12 months. Overall health-promoting behaviors, physical activity, stress management, and interpersonal relations improved in both groups between baseline and 12 months. Associations were found between alcohol consumption, personality traits, gender, and lifestyle health-promoting behaviors. In particular, impulsivity and hopelessness were associated with poor health behaviors. CONCLUSIONS: Intervention programs to reduce drinking by college students need to address developmental dynamics of freshmen students, including gender, psychosocial factors, personality, and lifestyle health-promoting behaviors.

3.
J Psychosoc Nurs Ment Health Serv ; 52(7): 38-45, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24627978

ABSTRACT

Drinking is pervasive in the lifestyle of many college students. This study investigated the relationship between drinking and students' impulsivity, sensation seeking, alcohol consequences, and expectancies. The study was based on the Acquired Preparedness Model, which posits that personality constructs like impulsivity and sensation seeking influence drinking through the formation of positive expectancies about the effects of drinking. Freshmen (N = 260) from a large public university volunteered for the study and were administered three surveys. Structural equation modeling was used to examine the study variables. The findings showed that the total effect of impulsivity was mediated by positive alcohol expectancies. The total effect of sensation seeking was mediated by alcohol expectancies. Freshmen who were more impulsive and sensation seeking had more positive alcohol expectancies and experienced more negative consequences related to alcohol use. These findings suggest that the risk of alcohol consequences was associated with personality constructs and alcohol expectancies.


Subject(s)
Alcohol Drinking/psychology , Impulsive Behavior , Personality Assessment , Students/psychology , Universities , Adolescent , Education, Nursing, Continuing , Female , Humans , Male , Risk Factors , Risk-Taking , Surveys and Questionnaires , Young Adult
4.
J Gen Psychol ; 137(4): 343-61, 2010.
Article in English | MEDLINE | ID: mdl-21086857

ABSTRACT

Previous studies have reported that our interpersonal knowledge shows an asymmetry; that is, we tend to believe that we know and understand other people's thoughts and feelings better than other people know and understand our own thoughts and feelings. In the present study, the authors compared American (114 men, 192 women) and Korean (99 men and 98 women) students to examine whether the asymmetry is greater in collectivistic than in individualistic culture in two types of relationships: horizontal (with best friends) and vertical (with parents). On all three items--Know, Understand, and Visibility--asymmetry was found for both horizontal and vertical relationships. Further, the Understand and Visibility items showed greater asymmetry for the Korean group than for the American group. It was concluded that asymmetry is greater in collectivistic than in individualistic culture. The cultural differences can be explained by self-consistency, sensitivity to social consequences, parent-child interaction, and living arrangement.


Subject(s)
Culture , Interpersonal Relations , Knowledge , Parent-Child Relations , Peer Group , Adult , Analysis of Variance , Cross-Cultural Comparison , Female , Humans , Male , Republic of Korea , United States
5.
Psychol Rep ; 100(3 Pt 2): 1165-70, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17886504

ABSTRACT

Concurrent validity of the WISC-III and WISC-IV was conducted using a sample of 35 students classified as educable mentally disabled. Full Scale IQ scores of previously administered WISC-III correlated .91 with WISC-IV Full Scale IQ scores when adjusted for restricted range. Of the previous eligibility decisions, 80% were confirmed by the WISC-IV scores. Implications of the findings and suggestions for research are discussed.


Subject(s)
Decision Making , Education, Special , Eligibility Determination , Persons with Mental Disabilities , Students , Surveys and Questionnaires , Adolescent , Child , Female , Humans , Male , Reproducibility of Results , Wechsler Scales
6.
Eur J Clin Microbiol Infect Dis ; 26(8): 583-6, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17564731

ABSTRACT

The Copan Diagnostics HealthLink Transporter swab and the Remel Bacti-Swab were evaluated by the Clinical and Laboratory Standards Institute M40-A quantitative swab elution method for maintenance of bacterial viability of six ATCC and six clinical strains. Acceptable levels of viability according to Clinical and Laboratory Standards Institute criteria were maintained for all organisms tested with the HealthLink Transporter swab and for 8 of 12 organisms tested with the Bacti-Swab. In this study, the HealthLink Transporter swab maintained organism viability better than the Bacti-Swab.


Subject(s)
Culture Media , Gram-Negative Bacteria/growth & development , Gram-Positive Bacteria/growth & development , Bacteriological Techniques/methods , Colony Count, Microbial , Specimen Handling/methods
8.
Psico (Porto Alegre) ; 33(2): 245-272, jul.-dez. 2002. tab
Article in Portuguese | Index Psychology - journals | ID: psi-21151

ABSTRACT

Foram avaliadas as relações interpessoais em 248 jovens brasileiros com as idades de 11-12, 15-16, e 19-20 anos, usando-se o Inventário da Rede de Relações (Furman e Buhrmester, 1992). Os participantes classificaram quatro dimensões de seus relacionamentos com membros da família, professores e amigos: apoio, conflito, poder relativo e punição. Muitos aspectos fundamentais destes relacionamentos são semelhantes nas duas culturas. Todavia , os brasileiros geralmente apresentam níveis mais altos de apoio, conflito, poder relativo e punição em seus relacionamentos, comparativamente aos adolescentes estadunidenses. Os pré-adolescentes brasileiros se assemelham mais aos estadunidenses do que os jovens universitários(AU)


Subject(s)
Humans , Male , Female , Adolescent , Adult , Interpersonal Relations , Cross-Cultural Comparison , Adolescent Behavior , Adolescent , Family Relations
9.
Psico (Porto Alegre) ; 33(2): 245-272, jul.-dez. 2002. tab
Article in Portuguese | LILACS | ID: lil-397523

ABSTRACT

Foram avaliadas as relações interpessoais em 248 jovens brasileiros com as idades de 11-12, 15-16, e 19-20 anos, usando-se o Inventário da Rede de Relações (Furman e Buhrmester, 1992). Os participantes classificaram quatro dimensões de seus relacionamentos com membros da família, professores e amigos: apoio, conflito, poder relativo e punição. Muitos aspectos fundamentais destes relacionamentos são semelhantes nas duas culturas. Todavia , os brasileiros geralmente apresentam níveis mais altos de apoio, conflito, poder relativo e punição em seus relacionamentos, comparativamente aos adolescentes estadunidenses. Os pré-adolescentes brasileiros se assemelham mais aos estadunidenses do que os jovens universitários


Subject(s)
Humans , Male , Female , Adolescent , Adult , Cross-Cultural Comparison , Interpersonal Relations , Adolescent , Adolescent Behavior , Family Relations
10.
Carcinogenesis ; 22(12): 2039-47, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11751437

ABSTRACT

It is well established that 85-90% of chemically induced mammary tumors in rats will disappear or diminish significantly in size after the ovaries are removed from the animal. However, it is less well established whether a high percentage of these mammary tumors will grow back with prolonged time after ovariectomy. It is also not known what changes in gene expression take place in the tumors as they develop an independence from hormones for growth. This study was carried out to investigate this. Virgin, 50-day-old female Sprague-Dawley rats were injected with N-methyl-N-nitrosourea (MNU) at the dose of 50 mg MNU/kg body wt. When at least one mammary tumor had grown to 1.0-1.5 cm in one dimension, the animal was bilaterally ovariectomized and reduction and then re-growth of the tumors monitored. Control animals were treated identically except they were not ovariectomized when tumors appeared. Re-growths and new tumors and tumors that developed in the control rats were removed when they reached 1.0-1.5 cm in diameter and all animals were killed 25 weeks after the MNU injection. All the animals in the study (100%) developed mammary tumors after MNU injection with an average latency of 56.5 days. After ovariectomy, 93% of the tumors showed 50% or more reduction in size and 76% of the tumors could not be detected by palpation. However, in 96% of the animals where tumor reduction or disappearance occurred, a re-growth or new mammary tumor development took place with an average latency period of 52.8 days from the day of ovariectomy. Of these post-ovariectomy tumors, 36% occurred at a location where tumors had developed prior to ovariectomy, but 64% appeared at new locations. The circulating levels of 17beta-estradiol (E2) was undetectable in the ovariectomized (OVX) rats and significant reduction was seen in the serum concentrations of progesterone (P4), prolactin (PRL), growth hormone (GH) and insulin-like growth factor-I (IGF-I). The tumors from the OVX rats showed indications of progression as evident from loss of differentiation and invasive characteristics. Comparison between tumors from OVX and intact rats revealed a significantly increased expression of P450 aromatase and elevated activation of extracellular signal-regulated kinase 1 and 2, but reduced levels of the progesterone receptor and cyclin D1 in OVX rats. However, the estrogen receptor (ER) content remained similar in tumors from both groups, at least at the protein level, and so did the expression of IGF-I, IGF-II, insulin receptor substrate-1 (IRS1), IRS-2 and epidermal growth factor receptor. IGF-I receptor (IGF-IR) and ErbB-2 were expressed, respectively, in 50 and 70% of the tumors from the OVX animals, whereas these genes were expressed in 100% of the tumors from the intact rats. It is concluded that chemically induced rat mammary tumors may still depend on the ER and local syntheses of E2 and growth factors for growth initially after ovariectomy. However, as these tumors progress, they develop a more aggressive phenotype and lose their dependency on the ER and possibly growth factors.


Subject(s)
Mammary Neoplasms, Experimental/chemically induced , Mammary Neoplasms, Experimental/pathology , Methylnitrosourea/toxicity , Ovariectomy , Animals , Aromatase/metabolism , Cell Differentiation , Cyclin D1/metabolism , ErbB Receptors/metabolism , Estradiol/blood , Estradiol/metabolism , Estrogen Receptor alpha , Female , Growth Hormone/blood , Mammary Neoplasms, Experimental/enzymology , Mammary Neoplasms, Experimental/metabolism , Mitogen-Activated Protein Kinases/metabolism , Prolactin/blood , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptor, ErbB-2/metabolism , Receptor, IGF Type 1/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/genetics , Receptors, Progesterone/metabolism , Ribonucleases/metabolism , Somatomedins/metabolism
11.
J Endocrinol ; 171(1): 85-95, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11572793

ABSTRACT

The importance of prolactin (PRL) in regulating growth and differentiation of the mammary gland is well known. However, it is not well established whether PRL acts solely on the mammary epithelia or if it can also directly affect the mammary stroma. To determine where PRL could exert its effects within the mammary gland, we investigated the levels of expression and the localization of the PRL receptor (PRLR) in the epithelia and stroma of the rat mammary gland at different physiological stages. For these studies, we isolated parenchymal-free 'cleared' fat pads and intact mammary glands from virgin, 18-day-pregnant and 6-day-lactating rats. In addition, intact mammary tissues were enzymatically digested to obtain epithelial cells, free of stroma. The mammary tissues, intact gland, stroma and isolated epithelia, were then used for immunocytochemistry, protein extraction and isolation of total RNA. PRLR protein was detected in tissues using specific polyclonal antisera (PRLR-l) by immunocytochemistry and Western blot analysis. Messenger RNA for PRLR was measured by ribonuclease protection assay. Immunocytochemistry and Western blots with the PRLR-1 antisera detected PRLR in wild-type rat and mouse tissues, whereas the receptor protein was absent in tissues from PRLR gene-deficient mice. PRLR was found to be present both in the epithelia and stroma of mammary glands from virgin, pregnant and lactating rats, as determined by immunocytochemistry and Western blotting. Western blots revealed the predominance of three bands migrating at 88, 90 and 92 kDa in each of the rat mammary samples. These represent the long form of the PRLR. During pregnancy and lactation, PRLR protein increased in the epithelial compartment of the mammary gland but did not change within the stromal compartment at any physiological stage examined. We also found PRLR mRNA in both the epithelia and stroma of the mammary gland. Again, the stroma contained lower levels of PRLR mRNA compared with the epithelia at all physiological stages examined. Also, the PRLR mRNA levels within the stroma did not change significantly during pregnancy or lactation, whereas PRLR mRNA within the epithelia increased twofold during pregnancy and fourfold during lactation when compared with virgin rats. We conclude from this study that PRLR is expressed both in the stromal and epithelial compartment of the mammary gland. This finding suggests PRL may have a direct affect on the mammary stroma and by that route affect mammary gland development.


Subject(s)
Mammary Glands, Animal/chemistry , Receptors, Prolactin/analysis , Animals , Blotting, Western/methods , Epithelial Cells/chemistry , Female , Immunohistochemistry/methods , Lactation , Pregnancy , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Receptors, Prolactin/genetics
12.
Carcinogenesis ; 22(7): 1027-33, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11408345

ABSTRACT

Parity in humans and rats provides significant protection against mammary tumor development. This study was carried out to investigate whether treatment of parous rats with mammotropic hormones would affect methyl-nitrosourea (MNU)-induced mammary carcinogenesis. Parous rats were treated with 17beta-estradiol (E2), progesterone (P4) and thyroxine (T4) alone or in combination. E2 (20 microg/60 days) and P4 (20 mg/60 days) were administered by silastic tubing and T4 in the drinking water (3 microg T4/ml). Hormonal treatments commenced 7 days before MNU injection and continued for 33 weeks. Animals were palpated weekly for tumor detection. The effects of the hormonal treatments on the circulating concentrations of E2, P4, growth hormone (GH), prolactin (PRL), T4 and insulin-like growth factor-I (IGF-I) after 7 days of treatment, the time of MNU injection, was assessed. Animals treated with E2 had significantly elevated circulation concentrations of GH, PRL and P4, and serum levels of E2 were more consistent in this group than in the other animal groups. P4 treatment caused elevation in P4 concentration in serum but did not affect the circulating levels of other hormones. The proliferation of the mammary gland at the time of MNU injection was elevated in animal groups treated with E2 either alone or with P4 and T4 and in animals treated with P4 alone, but the mammary gland was most differentiated in untreated parous rats and least in animals treated with E2 either alone or with P4 and T4. Mammary tumor incidence was 10% in parous rats that did not receive any hormonal treatment. Treatments with E2 or P4 alone significantly increased the susceptibility of parous animals to 67 and 50.0%, respectively; a tumor incidence similar to that of untreated AMV rats (64%). Parous rats treated with E2 plus P4 had tumor incidence higher than 90%. T4 administered did not affect mammary carcinogenesis.


Subject(s)
Carcinogens/toxicity , Estradiol/administration & dosage , Mammary Neoplasms, Experimental/chemically induced , Methylnitrosourea/toxicity , Progesterone/administration & dosage , Thyroxine/administration & dosage , Animals , Cyclin D , Cyclins/metabolism , DNA/metabolism , Female , Mammary Glands, Animal/growth & development , Mammary Glands, Animal/metabolism , Rats , Rats, Sprague-Dawley
13.
Cornea ; 20(2): 179-82, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11248825

ABSTRACT

PURPOSE: The conventional treatment of Nocardia keratitis is with topical sulfonamides. Recently, topical trimethoprim and sulfamethoxazole (Bactrim) has been suggested as treatment. This study compares the in vitro efficacy against Nocardia asteroides of Bactrim and various ratios of trimethoprim and a sulfonamide. METHODS: Antibiotic disks were soaked with various ratios of trimethoprim and sulfacetamide sodium. They contained trimethoprim alone, sulfacetamide sodium alone, and both trimethoprim and sulfacetamide sodium at ratios of 1:40, 1:20, and 1:5. Disks containing Bactrim were also prepared. Each disk was placed on blood agar plates streaked with N. asteroides. The plates were incubated at 37 degrees C for 72 hours and then examined. RESULTS: Trimethoprim alone showed minimal effect. Sulfacetamide sodium alone had a clearance zone of 12 mm. The plates of trimethoprim and sulfacetamide sodium at ratios of 1:40, 1:20, and 1:5 had clearance zones of 14 mm, 17 mm, and 27 mm, respectively. Bactrim had a clearance zone of 70 mm. CONCLUSION: Trimethoprim or sulfacetamide sodium alone is not as effective as both drugs together. As the ratio of the two drugs was changed, potency differed against Nocardia organisms. Bactrim was the most effective antibiotic against Nocardia organisms. It should be the recommended agent for the treatment of Nocardia keratitis.


Subject(s)
Anti-Infective Agents, Local/therapeutic use , Eye Infections, Bacterial/drug therapy , Keratitis/drug therapy , Nocardia Infections/drug therapy , Nocardia asteroides/isolation & purification , Sulfacetamide/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Trimethoprim/therapeutic use , Administration, Topical , Adult , Cornea/microbiology , Eye Infections, Bacterial/microbiology , Humans , Keratitis/microbiology , Male , Microbial Sensitivity Tests , Nocardia Infections/microbiology , Ophthalmic Solutions
14.
J Clin Microbiol ; 37(7): 2376-7, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10364622

ABSTRACT

Growth of microaerophilic bacteria in the AnaeroPack Campylo (Mitsubishi Gas Chemical America, Inc., New York, N.Y.) atmosphere generation system was compared to growth in the CampyPak Plus jar and CampyPak pouch (Becton-Dickinson Microbiology Systems [BDMS], Cockeysville, Md.). Growth in the AnaeroPack Campylo system was considered equivalent to or better than growth obtained in the CampyPak Plus and CampyPak pouch systems for 48 of the 50 Helicobacter pylori strains and for all 28 Campylobacter species tested. All of the 78 organisms tested were recovered in each system in equivalent colony counts. Two strains of H. pylori grown in the AnaeroPack Campylo system were observed to have colony morphology growth discrepancies when compared to growth in the two BDMS systems. Atmosphere failure with the AnaeroPack Campylo was not detected with Campylobacter jejuni ATCC 33291 used as a growth control. The AnaeroPack Campylo system is easy to use and supports the growth of campylobacters and H. pylori.


Subject(s)
Bacteriological Techniques , Campylobacter/growth & development , Helicobacter pylori/growth & development , Anaerobiosis , Bacteriological Techniques/instrumentation , Campylobacter/isolation & purification , Campylobacter jejuni/growth & development , Campylobacter jejuni/isolation & purification , Evaluation Studies as Topic , Helicobacter pylori/isolation & purification
15.
Pediatr Infect Dis J ; 18(4): 352-6, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10223689

ABSTRACT

BACKGROUND: After the occurrence of two cases of bloodstream infection with vancomycin-resistant enterococci (VRE) in our regional neonatal intensive care unit, we studied the epidemiology of VRE and applied extensive infection control measures to the unit to control VRE transmission. METHODS: Infection control measures applied to the unit included weekly surveillance for VRE colonization; education; cohorting of VRE-positive, VRE-negative and VRE-exposed babies with separate personnel and equipment for each group; use of gowns and gloves on room entry; and hand washing before and after each patient contact. Risk factors for VRE colonization were determined with a stepwise logistic regression model. RESULTS: Thirty-three (40.2%) babies became colonized with VRE. The VRE colonization rate was reduced from 67% to 7% after implementation of infection control measures. Prolonged antimicrobial treatment and low birth weight were significantly associated with an increased risk of VRE colonization. CONCLUSION: VRE can spread rapidly among newborns in a regional neonatal intensive care unit. Strict infection control measures can reduce the rate of VRE colonization among neonates.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cross Infection/prevention & control , Enterococcus/drug effects , Gram-Positive Bacterial Infections/prevention & control , Vancomycin/pharmacology , Cross Infection/epidemiology , Drug Resistance, Microbial , Electrophoresis, Gel, Pulsed-Field , Enterococcus/isolation & purification , Gram-Positive Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/epidemiology , Humans , Infant, Newborn , Infection Control , Intensive Care Units, Neonatal , Risk Factors
16.
Diagn Microbiol Infect Dis ; 31(4): 525-30, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9764390

ABSTRACT

The motile enterococci with the vanC gene have intrinsic low-level resistance to vancomycin, but have not been implicated in a nosocomial outbreak. We determined the colonization rate of motile enterococci in hospitalized and nonhospitalized patients. Perianal or stool specimens were cultured in Enterococcosel broth supplemented with 6 micrograms of vancomycin per mL. Rapid motility and pigment tests were performed on all enterococci isolated. A total of 82 motile and/or pigmented enterococci were isolated from 679 patients for a colonization rate of 12.1%. There were 43 Enterococcus gallinarum, 32 Enterococcus casseliflavus, 4 Enterococcus flavescens, and 3 Enterococcus mundtii identified. The E. gallinarum vancomycin MIC90 was 32 micrograms/mL and the E. casseliflavus vancomycin MIC90 was 8 micrograms/mL.


Subject(s)
Anal Canal/microbiology , Enterococcus/growth & development , Feces/microbiology , Anti-Bacterial Agents/pharmacology , Drug Resistance, Microbial , Enterococcus/drug effects , Enterococcus/isolation & purification , Enterococcus/physiology , Hospitalization , Humans , Microbial Sensitivity Tests , Movement , Vancomycin/pharmacology
18.
J Clin Microbiol ; 35(8): 2170-3, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9230409

ABSTRACT

Growth of anaerobic bacteria in the AnaeroPack (Mitsubishi Gas Chemical America, Inc., New York, N.Y.) anaerobic atmosphere generation systems, both the AnaeroPack jar and pouch and the AnaeroPack in a GasPak jar were considered equivalent to or better than growth obtained in the corresponding GasPak jar or pouch system (Becton Dickinson Microbiology Systems, Cockeysville, Md.) for 89 (86%) of the 103 anaerobes tested. There were a total of 26 discrepancies after 48 h of incubation, with 16 discrepancies unresolved after 96 h of incubation. The AnaeroPack jar and pouch never failed to reduce the anaerobic indicator. The AnaeroPack systems are easy to use and performed at least as well as or better than the BBL GasPak systems for growth of anaerobic bacteria.


Subject(s)
Bacteria, Anaerobic/growth & development , Bacteriological Techniques , Evaluation Studies as Topic
19.
Antimicrob Agents Chemother ; 41(8): 1697-703, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9257744

ABSTRACT

The antibacterial properties of bismuth are greatly enhanced when bismuth is combined with certain lipophilic thiol compounds. Antibacterial activity was enhanced from 25- to 300-fold by the following seven different thiols, in order of decreasing synergy: 1,3-propanedithiol, dimercaprol (BAL), dithiothreitol, 3-mercapto-2-butanol, beta-mercaptoethanol, 1-monothioglycerol, and mercaptoethylamine. The dithiols produced the greatest synergy with bismuth at optimum bismuth-thiol molar ratios of from 3:1 to 1:1. The monothiols were generally not as synergistic and required molar ratios of from 1:1 to 1:4 for optimum antibacterial activity. The most-active mono- or dithiols were also the most soluble in butanol. The intensity of the yellow formed by bismuth-thiol complexes reflected the degree of chelation and correlated with antibacterial potency at high molar ratios. The bismuth-BAL compound (BisBAL) was active against most bacteria, as assessed by broth dilution, agar diffusion, and agar dilution analyses. Staphylococci (MIC, 5 to 7 microM Bi3+) and Helicobacter pylori (MIC, 2.2 microM) were among the most sensitive bacteria. Gram-negative bacteria were sensitive (MIC, < 17 microM). Enterococci were relatively resistant (MIC, 63 microM Bi3+). The MIC range for anaerobes was 15 to 100 microM Bi3+, except for Clostridium difficile (MIC, 7.5 microM). Bactericidal activity averaged 29% above the MIC. Bactericidal activity increased with increasing pH and/or increasing temperature. Bismuth-thiol solubility, stability, and antibacterial activity depended on pH and the bismuth-thiol molar ratio. BisBAL was stable but ineffective against Escherichia coli at pH 4. Activity and instability (reactivity) increased with increasing alkalinity. BisBAL was acid soluble at a molar ratio of greater than 3:2 and alkaline soluble at a molar ratio of less than 2:3. In conclusion, certain lipophilic thiol compounds enhanced bismuth antibacterial activity against a broad spectrum of bacteria. The activity, solubility, and stability of BisBAL were strongly dependent on the pH, temperature, and molar ratio. Chelation of bismuth with certain thiol agents enhanced the solubility and lipophilicity of this cationic heavy metal, thereby significantly enhancing its potency and versatility as an antibacterial agent.


Subject(s)
Antacids/pharmacology , Bacteria/drug effects , Bismuth/pharmacology , Chelating Agents/pharmacology , Sulfhydryl Compounds/pharmacology , Colony Count, Microbial , Cysteamine/pharmacology , Dimercaprol/pharmacology , Dithiothreitol/pharmacology , Drug Combinations , Drug Synergism , Microbial Sensitivity Tests , Radiation-Protective Agents/pharmacology , Sulfhydryl Reagents/pharmacology
20.
Proc Natl Acad Sci U S A ; 94(15): 8132-7, 1997 Jul 22.
Article in English | MEDLINE | ID: mdl-9223327

ABSTRACT

The product of the WT1 Wilms tumor suppressor gene controls the expression of genes encoding components of the insulin-like growth factor and transforming growth factor beta signaling systems. The role of these growth factors in breast tumor growth led us to investigate possible WT1 gene expression in normal and cancerous breast tissue. WT1 was detected by immunohistochemistry in the normal mammary duct and lobule, and the patterns of expression were consistent with developmental regulation. In a survey of 21 infiltrating tumors, 40% lacked immunodetectable WT1 altogether and an additional 28% were primarily WT1-negative. Cytoplasmic, but not nuclear, localization of WT1 was noted in some tumor cells and WT1 was detected, sometimes at high levels, in more-advanced estrogen-receptor-negative tumors. In this highly malignant subset, the tumor suppressor protein p53, which can physically interact with WT1, was also sometimes detected. WT1 mRNA was detected in normal and tumor tissue by reverse transcription-coupled PCR. Alternative splicing of the WT1 mRNA may regulate gene targeting of the WT1 protein through changes either in its regulatory or zinc-finger domains. The relative proportions of WT1 mRNA splice variants were altered in a random sample of breast tumors, providing evidence that different tumors may share a common WT1-related defect resulting in altered regulation of target genes.


Subject(s)
Breast Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Genes, Wilms Tumor , Blotting, Southern , Genes, p53 , Humans , Immunohistochemistry
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