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1.
J Perinatol ; 37(1): 81-87, 2017 01.
Article in English | MEDLINE | ID: mdl-27711043

ABSTRACT

OBJECTIVE: Right ventricular (RV) performance among infants with bronchopulmonary dysplasia (BPD) remains poorly understood. We tested the hypothesis that myocardial deformation imaging (MDI) strain and strain rate would allow for differentiation between infants with severe and milder forms of BPD, independent of tissue Doppler imaging (TDI) and superior to conventional echocardiographic measurements. STUDY DESIGN: Infants with various severities of BPD (11 with none or mild, 13 with moderate and 10 with severe) underwent conventional echocardiography, TDI and MDI assessments at >36 weeks of corrected gestational age. BPD severity grading was determined according to the National Institutes of Child Health and Disease workshop rating scale by physicians blinded to the echocardiogram results. Group data were compared with one-way analysis of variance or Kruskal-Wallis tests, with post hoc multiple comparisons. RESULTS: No differences in traditional echocardiographic parameters or TDI among the three BPD severity groups were observed; none of the infants had evidence of pulmonary hypertension. Using MDI, infants with severe BPD had lower peak global systolic strain than did infants with moderate BPD (P<0.01) or mild/none BPD (P<0.01). Early and late diastolic strain rate measurements were similar across the three groups. CONCLUSIONS: Among infants with severe forms of BPD, evidence of abnormal RV systolic function was detected with MDI, but not traditional echocardiographic or TDI measurements. Infants with severe forms of BPD may represent a particularly high-risk subgroup for decreased RV performance warranting cardiac surveillance. MDI should be considered as a method to quantitate RV function in this population.


Subject(s)
Bronchopulmonary Dysplasia/diagnostic imaging , Bronchopulmonary Dysplasia/physiopathology , Heart Ventricles/diagnostic imaging , Myocardial Contraction , Ventricular Function, Right/physiology , Echocardiography, Doppler , Female , Heart Ventricles/physiopathology , Humans , Hypertension, Pulmonary/diagnostic imaging , Infant , Infant, Newborn , Male , Prospective Studies , Severity of Illness Index , United States
2.
J Perinatol ; 36(12): 1132-1137, 2016 12.
Article in English | MEDLINE | ID: mdl-27684422

ABSTRACT

OBJECTIVE: To evaluate the preparedness of pediatric residents entering accredited neonatal-perinatal medicine (NPM) fellowships in the United States. STUDY DESIGN: A multi-domain, validated survey was distributed to Program Directors (PDs) of US NPM fellowship programs. The 47-item survey explored 5 domains: professionalism, independent practice, psychomotor ability, clinical evaluation, and academia. A systematic, qualitative analysis on free-text comments was also performed. RESULTS: Sixty-one PDs completed the survey, for a response rate of 62% (61/98). For entering fellows, PDs assessed performance in professionalism positively, including 76% as communicating effectively with parents and 90% treating residents/house-staff with respect. In contrast, most PDs rated performance in psychomotor abilities negatively, including 59% and 79% as deficient in bag-and-mask ventilation and neonatal endotracheal intubation, respectively. Although 62% of PDs assessed entering fellows positively for genuine interest in academic projects, fewer than 10% responded positively that entering fellows understood research protocol design, basic statistics, or were capable of writing a cohesive manuscript well. Thematic clustering of qualitative data revealed deficits in psychomotor ability and academia/scholarship. CONCLUSIONS: On the basis of the perspective of front line educators, graduating pediatric residents are underprepared for subspecialty fellowship training in NPM. To provide the best preparation for pediatric graduates who pursue advanced training, changes to residency education to address deficiencies in these important competencies are warranted.


Subject(s)
Clinical Competence/standards , Fellowships and Scholarships/organization & administration , Internship and Residency/standards , Neonatology/education , Pediatrics/education , Biomedical Research/education , Curriculum , Humans , Surveys and Questionnaires , United States
3.
J Perinatol ; 35(10): 826-31, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26226244

ABSTRACT

OBJECTIVE: Delayed umbilical cord clamping (DCC) at birth may provide a better neonatal health status than early umbilical cord clamping (ECC). However, the safety and feasibility of DCC in infants with congenital heart disease (CHD) have not been tested. This was a pilot, randomized, controlled trial to establish the safety and feasibility of DCC in neonates with CHD. STUDY DESIGN: Pregnant women admitted >37 weeks gestational age with prenatal diagnosis of critical CHD were enrolled and randomized to ECC or DCC. For ECC, the umbilical cord was clamped <10 s after birth; for DCC, the cord was clamped ~120 s after delivery. RESULTS: Thirty infants were randomized at birth. No differences between the DCC and ECC groups were observed in gestational age at birth or time of surgery. No differences were observed across all safety measures, although a trend for higher peak serum bilirubin levels (9.2±2.2 vs 7.3±3.2 mg dl(-1), P=0.08) in the DCC group than in the ECC group was noted. Although similar at later time points, hematocrits were higher in the DCC than in the ECC infants during the first 72 h of life. The proportion of infants not receiving blood transfusions throughout hospitalization was higher in the DCC than in the ECC infants (43 vs 7%, log-rank test P=0.02). CONCLUSION: DCC in infants with critical CHD appears both safe and feasible, with fewer infants exposed to red blood cell transfusions than with ECC. A more comprehensive appraisal of this practice is warranted.


Subject(s)
Delivery, Obstetric/methods , Heart Defects, Congenital/blood , Term Birth/blood , Umbilical Cord/blood supply , Adult , Constriction , Erythrocyte Transfusion , Female , Gestational Age , Hematocrit , Humans , Infant , Infant, Newborn , Male , Pilot Projects , Pregnancy , Time Factors , Young Adult
4.
J Neonatal Perinatal Med ; 7(4): 257-67, 2014.
Article in English | MEDLINE | ID: mdl-25468622

ABSTRACT

Evidence is growing on the potential value of enhancing placental-fetal transfusion at birth, with recent endorsement of the practice by the World Health Organization and American College of Gynecologists. However, these recommendations provide clinicians with little guidance on the optimal practice among infants born extremely premature (<28 weeks gestation) and those requiring immediate resuscitation. The goals of this review are to: 1) provide rationale for better outcomes among extremely preterm infants following delayed cord clamping or umbilical cord "milking" than with immediate cord clamping; 2) describe clinical situations that warrant immediate cord clamping following delivery and explore the controversy regarding optimal cord clamping practice among extremely premature infants, including those requiring immediate resuscitation; 3) discuss the quality of evidence in this subgroup of infants; 4) consider areas for future research, with a focus on characterizing if placental-fetal transfusion affects the magnitude or timing of variables associated with physiological transition. The review provided herein suggests that delayed cord clamping or umbilical cord milking can be applied safely to infants born prior to 28 weeks gestation, but the lack of evidence on the best practice among infants born severely depressed and requiring immediate resuscitation, who comprise a greater proportion of infant deliveries at the lowest gestational ages, is recognized. Future studies using well-defined physiologic outcome measures are needed to understand the role of placental transfusion in premature infants' adaptations to extrauterine life.


Subject(s)
Blood Transfusion/methods , Infant, Extremely Premature , Placental Circulation/physiology , Umbilical Cord/physiology , Constriction , Female , Gestational Age , Humans , Infant, Newborn , Pregnancy , Pregnancy Outcome , Resuscitation , Time Factors
5.
Prostate Cancer Prostatic Dis ; 7(2): 170-7, 2004.
Article in English | MEDLINE | ID: mdl-15136786

ABSTRACT

INTRODUCTION AND OBJECTIVES: The efficacy of adjuvant and salvage external beam radiation (AXRT+SXRT) for prostate cancer after radical prostatectomy (RP) has been debated because of the inability to rule out systemic occult metastasis, uncertainty that radiation eradicates residual local disease and the potential of exacerbating impotency and incontinence. To characterize the effectiveness and treatment morbidity a retrospective review was performed. METHODS: In all, 38 patients received AXRT and 91 received SXRT. The SXRT group was stratified by PSA level, age, race, pathologic stage, margin status, worst Gleason sum, radiation dose and pelvic field. Complications evaluated were impotence and incontinence. Median follow-up was 60.2 months. RESULTS: The 5-y disease-free survival (DFS) rate was 61.3% for AXRT and 36.3% for SXRT. Multivariate analysis of the SXRT cohort showed Gleason score, pathologic stage and pre-XRT PSA to be predictors of disease recurrence. After XRT 26% had worsened continence. CONCLUSIONS: Patients who recur after RP whose pathologic stage is pT2 or pT3c, Gleason score of 8 or higher or pre-XRT PSA is >2.0 ng/dl may have microscopic metastatic disease and a decreased chance of cure with SXRT alone. Continence was further impaired after XRT.


Subject(s)
Neoplasm Recurrence, Local , Neoplasm Staging , Prostatectomy , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Radiation Injuries , Aged , Disease-Free Survival , Erectile Dysfunction/etiology , Humans , Male , Middle Aged , Morbidity , Prostatic Neoplasms/pathology , Radiotherapy, Adjuvant/adverse effects , Retrospective Studies , Salvage Therapy , Urinary Incontinence/etiology
6.
Tuberculosis (Edinb) ; 83(4): 223-49, 2003.
Article in English | MEDLINE | ID: mdl-12906835

ABSTRACT

The TB Structural Genomics Consortium is an organization devoted to encouraging, coordinating, and facilitating the determination and analysis of structures of proteins from Mycobacterium tuberculosis. The Consortium members hope to work together with other M. tuberculosis researchers to identify M. tuberculosis proteins for which structural information could provide important biological information, to analyze and interpret structures of M. tuberculosis proteins, and to work collaboratively to test ideas about M. tuberculosis protein function that are suggested by structure or related to structural information. This review describes the TB Structural Genomics Consortium and some of the proteins for which the Consortium is in the progress of determining three-dimensional structures.


Subject(s)
Genomics/organization & administration , Mycobacterium tuberculosis/genetics , Amino Acid Sequence , Bacterial Proteins/genetics , Genome, Bacterial , Humans , International Cooperation , Molecular Sequence Data , Mycobacterium tuberculosis/metabolism , Protein Conformation , Sequence Alignment
7.
J Lipid Res ; 42(11): 1891-6, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714858

ABSTRACT

In contrast to the multiple low abundance 2,4-dinitrophenylhydrazine-reactive tryptic peptides formed by oxidation of LDL with reagent HOCl in vitro, myeloperoxidase-catalyzed oxidation produces a dominant product in considerably greater yield and selectivity. This modified peptide had a single amino-terminal sequence corresponding to amino acids 53-66 of apolipoprotein B-100 (apoB-100), but its mass spectra indicated a significantly higher mass than could be reconciled with simple modifications of this peptide. Subsequent studies indicate that this product appears to result from N-chlorination of the N-terminal amino group of apoB-100 and dehydrohalogenation to the corresponding imine, which may form the hydrazone derivative directly, or after hydrolysis to the ketone. The methionine residue is oxidized to the corresponding sulfoxide, and the primary sequence peptide (residues 1-14 of apoB-100) is linked by the intramolecular disulfide bond between C-12 and C-61 to the peptide composed of residues 53-66, as we have observed previously (Yang, C-Y., T. W. Kim, S. A. Weng, B. Lee, M. Yang, and A. M. Gotto, Jr. 1990. Proc. Natl. Acad. Sci. USA. 87: 5523-5527) in unmodified LDL. The selective oxidation by myeloperoxidase of the N-terminal amine suggests strong steric effects in the approach of substrate to the enzyme catalytic site, an effect that may apply to other macromolecules and to cell surface molecules.


Subject(s)
Apolipoproteins B/metabolism , Peptide Fragments/metabolism , Peroxidase/metabolism , 2,4-Dinitrophenol , Amino Acid Sequence , Apolipoprotein B-100 , Apolipoproteins B/chemistry , Chlorine Compounds , Chromatography, High Pressure Liquid , Disulfides/metabolism , Humans , Hydrogen Peroxide/metabolism , Indicators and Reagents , Lipid Peroxidation , Lipoproteins, LDL/metabolism , Methionine/metabolism , Oxidation-Reduction , Peptide Fragments/chemistry , Spectrometry, Mass, Electrospray Ionization , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Sulfoxides/metabolism
8.
Cell Transplant ; 10(7): 639-44, 2001.
Article in English | MEDLINE | ID: mdl-11714199

ABSTRACT

Pravastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, is known to have suppressive effects on immune and inflammatory cells. We have previously shown in mice and dogs that this agent prevents primary nonfunction of islet iso- and autografts by reducing inflammation at the graft site. The present study was designed to further investigate whether pravastatin has a synergistic effect with cyclosporine (Cs) to prolong islet allograft survival in mice. Unpurified 3000 BALB/c newborn islets were transplanted under the renal capsule of a streptozotocin-diabetic C57BL/6 mouse. Pravastatin and Cs were administered for 10 days starting on the day of grafting (day 0). Five groups were set up based on the treatment protocol: group 1, treatment with 40 mg/kg pravastatin; group 2, 30 mg/kg Cs; group 3, 50 mg/kg Cs; group 4, 40 mg/kg pravastatin and 30 mg/kg Cs; group 5, vehicle alone. Graft survival was indicated by blood glucose levels sustained at <200 mg/dl, and graft rejection by >250 mg/dl for 2 consecutive days. Hyperglycemia persisted in six of the eight (75%) mice and grafts were rejected in 3.6 +/- 0.5 days (mean +/- SD) in group 5. In group 1, grafts were also rejected in 3.8 +/- 0.8 days, but blood glucose was transiently <200 mg/dl in three of the five mice. Despite Cs, grafts were rejected between 7 and 15 days (10.3 +/- 2.4 days) in group 2. Among six mice in group 3, one maintained euglycemia for >60 days, the other rejected the graft on day 15, and the remaining four died with functioning grafts between 9 and 13 days due to Cs toxicity. A combination of a low dose of Cs and pravastatin (group 4) prolonged graft survival for >19 days in five of the eight mice, and for 7-13 days in the remaining three mice. Histological examination of the grafts in this group showed significantly reduced local inflammation. Results indicate a synergistic effect of pravastatin and Cs on prevention of islet allograft rejection.


Subject(s)
Cyclosporine/pharmacology , Graft Survival/drug effects , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Immunosuppressive Agents/pharmacology , Islets of Langerhans Transplantation , Pravastatin/pharmacology , Animals , Blood Glucose , Body Weight , Drug Synergism , Hyperglycemia/pathology , Kidney/pathology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Transplantation, Homologous
9.
Toxicol Lett ; 123(2-3): 179-93, 2001 Sep 15.
Article in English | MEDLINE | ID: mdl-11641046

ABSTRACT

Patients with poorly functioning lungs often require treatment with high concentrations of supplemental oxygen, which, although often necessary to sustain life, can cause lung injury. The mechanisms responsible for hyperoxic lung injury have been investigated intensely and most probably involve oxidant stress responses, but the details are not well understood. In the present studies, we exposed adult male C57/Bl6 mice to >95% O2 for up to 72 h and obtained lung and liver samples for assessment of lung injury, measurements of tissue concentrations of coenzyme A (CoASH) and the corresponding mixed disulfide with glutathione (CoASSG), as possible biomarkers of intramitochondrial thiol redox status. Subcellular fractions were prepared from both tissues for determination of glutathione reductase (GR) activities. Lung injury in the hyperoxic mice was demonstrated by increases in lung weight to body weight ratios at 48 h and by increases in bronchoalveolar lavage protein concentrations at 72 h. Lung CoASH concentrations declined in the hyperoxic mice, but CoASSG concentrations were not increased nor were CoASH/CoASSG ratios decreased, as would be expected for an oxidant shift in mitochondrial thiol-disulfide status. Interestingly, CoASSG concentrations increased (from 6.72+/-0.54 to 14.10+/-1.10 nmol/g of liver in air-breathing controls and 72 h of hyperoxia, respectively, P<0.05), and CoASH/CoASSG ratios decreased in the livers of mice exposed to hyperoxia. Some apparent effects of duration of hyperoxia on GR activities in lung or liver cytosolic, mitochondrial, or nuclear fractions were observed, but the changes were not consistent or progressive. Yields of isolated hepatic nuclear protein were decreased in the hyperoxic mice within 24 h of exposure, and by 72 h of hyperoxia, protein recoveries in purified nuclear fractions had declined from 41.8 to 14.8 mg of protein/g animal body weight. Concentrations of 10-formyltetrahydrofolate dehydrogenase were diminished in hepatic mitochondria of hyperoxic mice. A second protein in hepatic mitochondria of approximately 25 kDa showed apparent decreases in thiol content, as determined by fluorescence intensities of monobromobimane derivatives separated by SDS-PAGE. The mechanisms responsible for the observed effects and the possible implications for the adverse effects of hyperoxic therapies are not known and need to be investigated.


Subject(s)
Hyperoxia/physiopathology , Liver/metabolism , Mitochondria, Liver/metabolism , Sulfhydryl Compounds/metabolism , Animals , Body Weight , Bronchoalveolar Lavage Fluid/chemistry , Coenzyme A/metabolism , Electrophoresis, Polyacrylamide Gel , Glutathione Reductase/metabolism , Liver/pathology , Lung/metabolism , Lung/pathology , Male , Mice , Mice, Inbred C57BL , Organ Size , Oxidation-Reduction , Time Factors
10.
BJOG ; 108(8): 804-8, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11510703

ABSTRACT

OBJECTIVES: To assess expression of the immunosuppressive cytokines IL-10 and TGF-beta in the ascitic fluid and plasma of advanced ovarian cancer patients. DESIGN: A prospective study. SETTING: The Department of Obstetrics and Gynaecology at the University of Arkansas for Medical Sciences. POPULATION: Twenty-eight women diagnosed with advanced ovarian cancer and ten normal female controls. METHODS: Plasma and ascitic samples were collected at the time of surgery and analysed for the presence of IL-10 and TGF-beta using a sensitive enzyme-linked immunosorbent assay. RESULTS: Elevated levels of IL-10 were detected in the plasma [mean (SD) = 12 (5) pg/mL; range 8 to 23 pg/mL] and in the peritoneal fluid [mean (SD) = 165 (137) pg/mL; range 50 to 556 pg/mL] of ovarian cancer patients, while no detectable IL-10 was found in any of the normal control plasma samples tested. Similarly, plasma levels of TGF-beta in ovarian cancer patients were significantly higher [mean (SD) = 1,506 (246) pg/mL; range 1,020 to 2,070 pg/mL] compared with controls [mean (SD) = 937 (187) pg/mL; range 770 to 1,140 pg/mL](P < 0.001). Surprisingly, however, although elevated TGF-beta levels were also detected in the peritoneal fluid of all ovarian cancer patients [mean (SD) = 407 (158) pg/mL; range 140 to 770 pg/mL], these levels were significantly lower than those seen in matched plasma samples (P < 0.001). CONCLUSIONS: Local and systemic secretion of immunosuppressive cytokines may play an important role in the impaired anti-tumour immune function commonly observed in advanced ovarian cancer. However, the observation that plasma levels of TGF-beta are significantly higher than those detected in the ascitic fluid raises the possibility that cells other than tumour cells are responsible for TGF-beta release in the bloodstream of these patients.


Subject(s)
Ascitic Fluid/metabolism , Interleukin-10/metabolism , Neoplasm Proteins/metabolism , Ovarian Neoplasms/metabolism , Transforming Growth Factor beta/metabolism , Adult , Aged , Aged, 80 and over , Case-Control Studies , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Middle Aged , Ovarian Neoplasms/blood , Ovarian Neoplasms/immunology , Prospective Studies
11.
Pancreas ; 23(1): 62-7, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11451149

ABSTRACT

The digestion of pancreatic tissue with collagenase is an essential part of the islet isolation procedure. However, the process exposes islets to various types of harmful factors, including collagenase contaminants, enzymes released from the acinar cells, warm ischemia, and mechanical agitation. Nitrogen oxide production and cytokine release may also contribute to islet cell damage. Protection of islets from such damage would improve the islet yield, survival, and function. Beraprost sodium (BPS) is a prostaglandin I2 analogue, is stable in aqueous solution, and has a cytoprotective effect on various types of cells. BPS has been shown to improve the yield and function of cryopreserved and/or cultured islets. These findings prompted us to examine its cytoprotective effect on islets during the islet isolation process. Canine islets were isolated by means of a two-step digestion method and purified on Euro-Ficoll density gradient solutions (the procedure used for human islets). BPS at a concentration of 100 nM was added to the collagenase solution. After purification, the islet yield was 434,561 +/- 35.691 islet number expressed as 150 microm equivalent size (IEQ)/pancreas or 8,799 +/- 345 IEQ/g of pancreas in the BPS group and 349,987 +/- 52,887 IEQ/pancreas or 7,998 +/-1610 IEQ/g of pancreas in the control group (n = 8, each). The percent viability was 88.5 +/- 0.7% in the BPS group and 82.0 +/-0.9% in the control group (P < 0.01). Therefore, the recovery of viable islets (calculated by islet number x % viability) was 384,586 +/- 46,804 IEQ/pancreas (7,743 IEQ/g) in the BPS group and 286,989 +/- 43,367 IEQ/pancreas (6,558 IEQ/g) in the control group (P < 0.02). After culture, significantly higher numbers of islets were also recovered in the BPS group than in the control group. The islet insulin content was significantly higher in the BPS group than controls (237.8 +/- 38.5 versus 92.3 +/- 25.6 microU/IEQ; P < 0.02), although islets of both groups responded with high stimulation indices (>6). These results indicate that the addition of BPS to the collagenase solution increases the recovery of viable islets, and improves beta cell function.


Subject(s)
Cell Separation/methods , Collagenases/pharmacology , Epoprostenol/analogs & derivatives , Epoprostenol/pharmacology , Islets of Langerhans Transplantation/methods , Islets of Langerhans/cytology , Animals , Cell Count , Cell Survival/drug effects , Cells, Cultured/chemistry , Cells, Cultured/metabolism , Cells, Cultured/transplantation , Centrifugation, Density Gradient , Cryoprotective Agents/pharmacology , Dogs , Insulin/analysis , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/chemistry , Islets of Langerhans/drug effects , Islets of Langerhans/metabolism , Solutions , Temperature
12.
Am J Respir Crit Care Med ; 164(1): 155-61, 2001 Jul 01.
Article in English | MEDLINE | ID: mdl-11435254

ABSTRACT

Bronchopulmonary dysplasia (BPD) is a chronic lung disease that affects prematurely born infants and appears to evolve in part from early inflammatory responses in the lung. The inflammatory responses have been associated with protein and lipid oxidation in tracheal aspirate fluids. The present study was designed to test the hypothesis that in the first week of life specific oxidations and/ or altered expressions of proteins would be observed in tracheal aspirate fluids in infants who would subsequently develop BPD. We obtained tracheal aspirate fluids on Days of life 1, 3, and 6 from infants born at < or = 29 wk gestation, incubated the fluids with 2,4-dinitrophenylhyrazine (DNPH), separated the proteins electrophoretically, and assessed DNPH reactivity by immunonblots. DNPH reactivity of a protein that was identified as Clara cell secretory protein (CCSP) was observed more consistently in tracheal aspirate fluids from infants who later developed BPD than from infants who did not develop BPD. Tracheal aspirate fluid levels of immunoreactive CCSP were also lower on Day of life 1 in infants who developed BPD than in those who did not develop BPD. Increased CCSP oxidation and decreased immunoreactive CCSP expression in infants who subsequently developed BPD suggest that Clara cell function and CCSP expression may be critical for normal bronchoalveolar fluid homeostasis and that maintaining CCSP expression and function may be useful goals for targeted therapies for inhibition of the development of BPD.


Subject(s)
Bronchopulmonary Dysplasia/metabolism , Enzyme Inhibitors/metabolism , Infant, Premature , Proteins/metabolism , Trachea/metabolism , Uteroglobin , Analysis of Variance , Blotting, Western , Humans , Infant, Newborn , Oxidation-Reduction , Predictive Value of Tests , Prospective Studies , Proteins/isolation & purification
13.
Ergonomics ; 44(8): 766-80, 2001 Jun 20.
Article in English | MEDLINE | ID: mdl-11450875

ABSTRACT

The purpose of this study was to quantify the metabolic demand of simulated shipboard fire-fighting procedures currently practised by men and women in the Royal Navy (RN) and to identify a minimum level of cardiovascular fitness commensurate with satisfactory performance. Thirty-four males (M) and 15 females (F) volunteered as subjects for this study (n=49). Maximal oxygen uptake (VO2max) and heart rate (fcmax) of each subject was assessed during a standardized treadmill test. During the main trials, volunteers were randomly assigned to complete several 4-min simulated shipboard fire-fighting tasks (boundary cooling (BC), drum carry (DC), extinguisher carry (EC), hose run (HR), ladder climb (LC)), at a work rate that was endorsed as a minimum acceptable standard. Heart rate (fc) and oxygen uptake (VO2) were recorded at 10-s intervals during rest, exercise and recovery. Participants completed all tasks within an allocated time with the exception of the DC task, where 11 subjects (all females) failed to maintain the endorsed work rate. The DC task elicited the highest (p<0.01) group mean peak metabolic demand (PMD) in males (43 ml min(-1) kg(-1)) and females (42 ml min(-1) kg (-1)) who were able to maintain the endorsed work rate. The BC task elicited the lowest PMD (23 ml min(-1) kg(-1)), whilst the remaining three tasks elicited a remarkably similar PMD of 38-39 ml min(-1) kg(-1). The human endurance limit while wearing a self-contained breathing apparatus (SCBA) dictates that RN personnel are only able to fire-fight for 20-30 min, while wearing a full fire-fighting ensemble (FFE) and performing a combination of the BC, HR and LC tasks, which have a group mean metabolic demand of 32.8 ml min(-1) kg(-1). Given that in healthy subjects fire-fighting can be sustained at a maximum work intensity of 80% VO2max when wearing SCBA for this duration, it is recommended that all RN personnel achieve a VO2max of 41 ml min(-1) kg(-1) as an absolute minimum standard. Subjects with a higher VO2max than the above quoted minimum are able to complete the combination of tasks listed with greater metabolic efficiency and less fatigue.


Subject(s)
Energy Metabolism/physiology , Fires/prevention & control , Military Personnel , Ships , Female , Heart Rate , Humans , Inservice Training , Male , Reproducibility of Results , Sex Factors , Task Performance and Analysis , United Kingdom
14.
Gynecol Obstet Invest ; 51(4): 254-61, 2001.
Article in English | MEDLINE | ID: mdl-11408737

ABSTRACT

To investigate and compare the phenotype and function of lymphocytes collected from patients harboring advanced ovarian cancer, leukocytes from peripheral blood (n = 18), ascitic fluid (n = 13) and tumor tissues (n = 13) were evaluated for the relative proportions of lymphocyte subsets, including CD3+, CD4+, CD8+, CD19+, CD56 and the early (CD25) and late (HLA-DR) activation markers on CD3+ T cells. The ability to synthesize type 1 cytokines (IFN-gamma and IL-2) and a type 2 cytokine (IL-4) was assessed by flow cytometry. In all patients, T cells (CD3+) were the major leukocyte population detected in each tissue, with CD4+ T cells being dominant in peripheral blood lymphocytes (PBL) and tumor-associated lymphocytes (TAL) but not in tumor-infiltrating lymphocytes (TIL) (CD4:CD8 ratios: 3.0 vs. 2.0 vs. 1.0, respectively). CD19+ lymphocytes (B cells) and CD56+ lymphocytes (NK cells) were significantly higher in PBL compared to TAL and TIL (p < 0.05). TAL and TIL had a higher proportion of T cells expressing the late activation marker HLA-DR compared to PBL. In contrast, no significant differences were detected in PBL, TAL and TIL in the expression of the early activation marker CD25. Type 1 cytokines were the dominant type produced by in vitro stimulated T cells for each population, with a greater proportion of IFN-gamma+ T cells in TAL and TIL compared to PBL (p < 0.01), and a higher proportion of IL-2+ T cells in PBL compared with TAL and TIL (p < 0.05). Low percentages of IL-4+ T cells (i.e. Th2) were detected in each tissue. Taken together, these data demonstrate the recruitment and accumulation of high concentrations of antigen-experienced T lymphocytes in TAL and TIL compared to PBL. However, low surface expression of IL-2 receptor (i.e. CD25), as well as depressed intracellular IL-2 production in chronically stimulated TAL and TIL suggests that the impaired antitumor function commonly detected in these lymphocyte populations may be secondary to an acquired dysregulation of the IL-2 pathway.


Subject(s)
Ascitic Fluid/immunology , Immunophenotyping , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes/immunology , Ovarian Neoplasms/immunology , Adult , Aged , Aged, 80 and over , CD4-CD8 Ratio , Female , Flow Cytometry , Humans , Interferon-gamma/analysis , Interferon-gamma/biosynthesis , Interleukin-2/analysis , Interleukin-2/biosynthesis , Interleukin-4/analysis , Interleukin-4/biosynthesis , Lymphocyte Count , Lymphocyte Subsets , Lymphocytes/physiology , Lymphocytes, Tumor-Infiltrating/physiology , Middle Aged
15.
Nutr Rev ; 59(1 Pt 1): 10-7, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11281247

ABSTRACT

Bronchopulmonary dysplasia (BPD) is a chronic lung disease common in premature infants that can cause severe complications. BPD's pathogenesis is multifactorial but oxidative processes during the first week of life are thought to play a key role in the development of the disease. Prevention of this oxidation through antioxidant therapy is therefore of interest. Unfortunately, this therapy has not proven effective, most likely owing to the nonspecific strategy used. This review focuses on the challenges facing researchers and clinicians in improving the antioxidant status of premature infants in order to prevent or lessen the severity of BPD. This review will focus on the particular oxidations that may lead to BPD and the specific therapies that can be used to counter these processes.


Subject(s)
Antioxidants/therapeutic use , Bronchopulmonary Dysplasia/drug therapy , Bronchopulmonary Dysplasia/prevention & control , Humans , Infant, Newborn , Infant, Premature , Oxidation-Reduction
17.
Dermatol Surg ; 27(2): 153-7, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11207689

ABSTRACT

BACKGROUND: Ocular damage may occur from a number of mechanisms during laser use. OBJECTIVE: To review issues relevant to ocular protection during laser resurfacing. METHODS: The authors were consulted to evaluate the thermal energy transferred from the outer to the inner (ie, corneal contact) surface of stainless steel eyeshields following direct exposure to the carbon dioxide (CO2) resurfacing laser beam. Measurements were obtained using thermocouples (attached to the inner surface of the eyeshields) and analyzed with a computer-based acquisition system. RESULTS: A maximum eyeshield temperature increase of 13 degrees C above the ambient temperature was noted following one pass with a CO2 resurfacing laser (Sharplan continuous CO2 laser with Clinicon SureScan scanner, 15 W, 950 microsec pulse duration, square spot of 9 mm). CONCLUSION: The eyeshields analyzed in this study minimized thermal transfer following a single direct hit with a CO2 resurfacing laser. An understanding of the potential mechanisms of ocular injury is essential in preventing its occurrence.


Subject(s)
Anti-Infective Agents, Local/adverse effects , Chlorhexidine/adverse effects , Corneal Injuries , Eye Protective Devices , Face/surgery , Laser Therapy/adverse effects , Stainless Steel , Burns/etiology , Burns, Chemical/etiology , Carbon Dioxide , Cornea/drug effects , Female , Humans , In Vitro Techniques , Lasers , Middle Aged , Temperature
18.
Virology ; 290(1): 99-105, 2001 Nov 10.
Article in English | MEDLINE | ID: mdl-11887784

ABSTRACT

Human papillomavirus (HPV) infection is threefold more prevalent in spontaneous abortion specimens compared to elective abortions preferentially targeting the placental trophoblasts in these specimens. Here by using infectious ceplar and Southern blot analysis, we demonstrate that the transfected HPV-16 genome de novo replicates in 3A trophoblasts in culture. Peak DNA replication occurred 9-24 days posttransfection, showing classic DNA forms I, II, and III and an 8-kb monomer band upon DpnI/BamHI digestion. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of mRNA expression revealed that E6 and E2 were significantly expressed by day 9, coinciding with HPV-16 DNA replication. However, significant L1 expression was delayed until day 18. L1 protein expression on day 18, but not day 9, was also confirmed by Western blot analysis. The production of HPV-16 virions was demonstrated by three techniques: the appearance of HPV-16 infectious units coinciding with L1 expression, the neutralization of these infectious units with known neutralizing anti-HPV-16 antibodies, and the appearance of spliced E1-E4 and E6-E7 transcripts (RT-PCR) in normal keratinocyte rafts infected with these trophoblast-produced HPV-16 infectious units. These data suggest that HPV-16 is carrying out its complete life cycle in trophoblasts. Previously, HPVs were known to productively replicate only in differentiating keratinocytes of skin. These findings expand HPV biology, support the hypothesis of a possible link between HPV and some spontaneous abortions, and present a new technology for studying HPV.


Subject(s)
Papillomaviridae/physiology , Trophoblasts/virology , Cells, Cultured , DNA Replication , DNA, Viral/biosynthesis , Gene Expression , Genes, Viral , Humans , Papillomaviridae/genetics , Placenta/cytology , Time Factors , Trophoblasts/cytology , Virion
20.
J Urol ; 164(6): 1964-7, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11061892

ABSTRACT

PURPOSE: Prostate cancer in men age 50 years or younger traditionally has accounted for approximately 1% of those diagnosed with prostate cancer. Prior studies of prostate cancer in men of this age led many clinicians to believe that they have a less favorable outcome than older men. Most of these studies were conducted before the advent of prostate specific antigen (PSA) screening programs. We evaluated a surgically treated cohort of men age 50 years or younger to determine whether disease recurred more frequently among them than in those 51 to 69 years old in the PSA era. MATERIALS AND METHODS: We reviewed the medical records of 477 men who underwent radical prostatectomy between 1988 and 1997. Age, ethnicity, preoperative PSA, clinical and pathological stage, margin and seminal vesicle involvement, and recurrence were compared between 79 men age 50 years or younger (study group) and 398, 51 to 69 years old (comparison group). Disease-free survival rates were compared using Kaplan-Meier and Cox regression techniques. RESULTS: There were 6 (7.6%) recurrences in the study group (79) and 107 (26.9%) in the comparison group (398). The disease-free survival curves were significantly different (log-rank p = 0.010). Age remained a significant prognostic factor (Wald p = 0.033) in multivariate Cox regression analyses that controlled for race, clinical and pathological stage, and pretreatment PSA. Similar results were found when the comparison group was limited to 116 patients 51 to 59 years old (log-rank p = 0.034, Wald p = 0.069). CONCLUSIONS: These data suggest that patients in the PSA era who underwent radical prostatectomy and were age 50 years or younger have a more favorable disease-free outcome compared to older men.


Subject(s)
Adenocarcinoma/pathology , Prostatic Neoplasms/pathology , Adenocarcinoma/mortality , Adenocarcinoma/surgery , Age Factors , Aged , Databases, Factual , Disease-Free Survival , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Prognosis , Prostate-Specific Antigen/analysis , Prostatectomy , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/mortality , Prostatic Neoplasms/surgery , Retrospective Studies
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