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2.
Article in English | MEDLINE | ID: mdl-28473924

ABSTRACT

BACKGROUND: Vietnam is experiencing an epidemiologic transition with an increased prevalence of non-communicable diseases. Novel, large-scale, effective, and sustainable interventions to control hypertension in Vietnam are needed. We report the results of a cluster-randomized feasibility trial at 3 months follow-up conducted in Hung Yen province, Vietnam, designed to evaluate the feasibility and acceptability of two community-based interventions to improve hypertension control: a "storytelling" intervention, "We Talk about Our Hypertension," and a didactic intervention. METHODS: The storytelling intervention included stories about strategies for coping with hypertension, with patients speaking in their own words, and didactic content about the importance of healthy lifestyle behaviors including salt reduction and exercise. The didactic intervention included only didactic content. The storytelling intervention was delivered by two DVDs at 3-month intervals; the didactic intervention included only one installment. The trial was conducted in four communes, equally randomized to the two interventions. RESULTS: The mean age of the 160 study patients was 66 years, and 54% were men. Most participants described both interventions as understandable, informative, and motivational. Between baseline and 3 months, mean systolic blood pressure declined by 8.2 mmHg (95% CI 4.1-12.2) in the storytelling group and by 5.5 mmHg (95% CI 1.4-9.5) in the didactic group. The storytelling group also reported a significant increase in hypertension medication adherence. CONCLUSIONS: Both interventions were well accepted in several rural communities and were shown to be potentially effective in lowering blood pressure. A large-scale randomized trial is needed to compare the effectiveness of the two interventions in controlling hypertension. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02483780.

3.
Phys Rev Lett ; 117(22): 220401, 2016 Nov 25.
Article in English | MEDLINE | ID: mdl-27925719

ABSTRACT

We demonstrate a novel way of synthesizing spin-orbit interactions in ultracold quantum gases, based on a single-photon optical clock transition coupling two long-lived electronic states of two-electron ^{173}Yb atoms. By mapping the electronic states onto effective sites along a synthetic "electronic" dimension, we have engineered fermionic ladders with synthetic magnetic flux in an experimental configuration that has allowed us to achieve uniform fluxes on a lattice with minimal requirements and unprecedented tunability. We have detected the spin-orbit coupling with fiber-link-enhanced clock spectroscopy and directly measured the emergence of chiral edge currents, probing them as a function of the flux. These results open new directions for the investigation of topological states of matter with ultracold atomic gases.

4.
Birth ; 40(4): 247-55, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24344705

ABSTRACT

BACKGROUND: To examine the episiotomy incidence and determinants and outcomes associated with its use in primary care midwifery practices. METHODS: Secondary analysis of two prospective cohort studies (n = 3,404). RESULTS: The episiotomy incidence was 10.8 percent (20.9% for nulliparous and 6.3% for parous women). Episiotomy was associated with prolonged second stage of labor (adj. OR 12.09 [95% CI 6.0-24.2] for nulliparous and adj. OR 2.79 [1.7-4.6] for parous women) and hospital birth (adj. OR 1.75 [1.2-2.5] for parous women). Compared with episiotomy, perineal tears were associated with a lower rate of postpartum hemorrhage in parous women (adj. OR 0.58 [0.4-0.9]). Fewer women with perineal tears reported perineal discomfort (adj. OR 0.35 [0.2-0.6] for nulliparous and adj. OR 0.22 [0.1-0.3] for parous women). Among nulliparous women episiotomy was performed most frequently for prolonged second stage of labor (38.8%) and among parous women for history of episiotomy or prevention of major perineal trauma (21.1%). CONCLUSIONS: The incidence of episiotomy is high compared with some low-risk settings in other Western countries. Episiotomy was associated with higher rates of adverse maternal outcomes. Restricted use of episiotomy is likely to be beneficial for women.


Subject(s)
Episiotomy/statistics & numerical data , Obstetric Labor Complications/surgery , Adult , Episiotomy/adverse effects , Female , Humans , Incidence , Labor Stage, Second , Logistic Models , Midwifery , Multivariate Analysis , Netherlands , Obstetric Labor Complications/prevention & control , Perineum/injuries , Postpartum Hemorrhage/epidemiology , Postpartum Hemorrhage/etiology , Pregnancy , Risk Factors , Treatment Outcome
5.
Mol Pharm ; 9(4): 930-6, 2012 Apr 02.
Article in English | MEDLINE | ID: mdl-22376068

ABSTRACT

Nanotechnology is playing an increasing role in targeted drug delivery into pathological tissues. Drug-loaded pharmaceutical nanocarriers can be delivered into diseased sites by passive targeting (spontaneous accumulation of nanocarriers in the areas with affected vasculature) or by active targeting (via site-specific ligands attached to the surface of drug-loaded nanocarriers). Subsequent level of targeting requires cellular internalization of nanocarriers and their specific association with certain individual cell organelles. The control over intracellular distribution of pharmaceutical nanocarriers requires effective and noninvasive methods of their visualization inside cells. In an attempt to enhance cellular internalization of pharmaceutical nanocarriers and their association with mitochondria specifically, we have prepared three types of cationic liposomes and investigated their intracellular distribution. The analysis was performed using Raman microspectroscopy in order to provide morphological information as well as biochemical signatures of the sample. It was demonstrated that Raman microscopy allows evaluation of the extent of mitochondrial association depending on the liposome composition.


Subject(s)
Drug Carriers/chemistry , Liposomes/chemistry , Nanoparticles/chemistry , Spectrum Analysis, Raman/methods , HeLa Cells , Humans
6.
J Gastroenterol Hepatol ; 27(2): 238-47, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22098550

ABSTRACT

Despite a high prevalence of liver disease in Viet Nam, there has been no nationwide approach to the disease and no systematic screening of at-risk individuals. Risk factors include chronic hepatitis B (estimated prevalence of 12%), chronic hepatitis C (at least 2% prevalence), and heavy consumption of alcohol among men. This combination of factors has resulted in liver cancer being the most common cause of cancer death in Viet Nam. There is a general lack of understanding by both the general public and health-care providers about the major risk to health that liver disease represents. We report here the initial steps taken as part of a comprehensive approach to liver disease that will ultimately include nationwide education for health-care providers, health educators, and the public; expansion of nationwide screening for hepatitis B and C followed by hepatitis B virus vaccination or treatment of chronic hepatitis B and/or hepatitis C; education about alcoholic liver disease; long-term surveillance for liver cancer; reduction of infection transmission related to medical, commercial, and personal re-use of contaminated needles, syringes, sharp instruments, razors, and inadequately sterilized medical equipment; and ongoing collection and analysis of data about the prevalence of all forms of liver disease and the results of the expanded screening, vaccination, and treatment programs. We report the beginning results of our pilot hepatitis B screening program. We believe that this comprehensive nationwide approach could substantially reduce the morbidity and mortality from liver disease and greatly lessen the burden in terms of both lives lost and health-care costs.


Subject(s)
Health Knowledge, Attitudes, Practice , Liver Diseases , Mass Screening , National Health Programs , Patient Education as Topic , Practice Patterns, Physicians' , Asian People , Delivery of Health Care, Integrated , Early Diagnosis , Female , Health Services Accessibility , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/ethnology , Hepatitis B, Chronic/prevention & control , Hepatitis B, Chronic/therapy , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/ethnology , Hepatitis C, Chronic/prevention & control , Hepatitis C, Chronic/therapy , Humans , Liver Diseases/diagnosis , Liver Diseases/ethnology , Liver Diseases/prevention & control , Liver Diseases/therapy , Liver Diseases, Alcoholic/diagnosis , Liver Diseases, Alcoholic/ethnology , Liver Diseases, Alcoholic/prevention & control , Liver Diseases, Alcoholic/therapy , Liver Neoplasms/diagnosis , Liver Neoplasms/ethnology , Liver Neoplasms/prevention & control , Liver Neoplasms/therapy , Male , Mass Screening/methods , Predictive Value of Tests , Prevalence , Prognosis , Program Development , Time Factors , Vietnam/epidemiology
7.
Technol Cancer Res Treat ; 10(2): 135-44, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21381791

ABSTRACT

The detection of micro-metastases and individual metastatic cells in lymph node tissue by spectral methods is summarized. These methods are based on instrument-based acquisition of thousands of infrared spectra of individual tissue pixels from the tissue section, and analysis of the resulting spectral hypercube by multivariate algorithms. The method of infrared image acquisition, followed by multivariate analysis, is henceforth referred to as Spectral Histopathology (SHP). SHP produces pseudo-color images of tissue sections which reveal details that compare very favorably with images collected from hematoxylin/eosin (H and E) stained tissues in that the same tissue structures are detected. However, the infrared results are based on objective and reproducible measurements and do not depend on subjective interpretation. One of the major topics of this paper is the comparison of spectral patterns observed for the same cancer type from different patients. While this is easy in some tissue types, we found it to be difficult in tissues of very different cellularity, or tissue sections that exhibit high levels of inflammatory response. In both cases, spectral quality will be compromised due to confounding effects resulting from scattering effects. The correction of these effects now permits the direct comparison of different patient samples, and paves the way for diagnostic algorithms for cancer detection to be developed.


Subject(s)
Lymph Nodes/pathology , Lymphatic Metastasis/diagnosis , Algorithms , Cluster Analysis , Humans , Multivariate Analysis , Signal Processing, Computer-Assisted , Spectroscopy, Fourier Transform Infrared/methods
8.
Int J Clin Pract ; 64(5): 611-8, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20456214

ABSTRACT

AIM: To examine the association between semi-sitting and sitting position at the time of birth and perineal damage amongst low-risk women in primary care. BACKGROUND: Evidence on the association between birthing positions and perineal trauma is not conclusive. Most studies did not distinguish between positions during the second stage of labour and position at the time of birth. Therefore, although birthing positions do not seem to affect the overall perineal trauma rate, an increase in trauma with upright position for birthing cannot be ruled out. METHODS: Secondary analysis was performed on data from a large trial. This trial was conducted amongst primary care midwifery practices in the Netherlands. A total of 1646 women were included who had a spontaneous, vaginal delivery. Perineal outcomes were compared between women in recumbent, semi-sitting and sitting position. Logistic regression analysis was used to examine the effects of these positions after controlling for other factors. FINDINGS: No significant differences were found in intact perineum rates between the position groups. Women in sitting position were less likely to have an episiotomy and more likely to have a perineal tear than women in recumbent position. After controlling for other factors, the odds ratios (OR) were 0.29 [95% confidence interval (CI): 0.16-0.54] and 1.83 (95% CI: 1.22-2.73) respectively. Women in semi-sitting position were more likely to have a labial tear than women in recumbent position (OR: 1.43, 95% CI: 1.00-2.04). CONCLUSION: A semi-sitting or sitting birthing position does not need to be discouraged to prevent perineal damage. Women should be encouraged to use positions that are most comfortable to them.


Subject(s)
Delivery, Obstetric/methods , Obstetric Labor Complications/etiology , Patient Positioning/methods , Perineum/injuries , Adult , Birth Weight , Female , Humans , Labor Stage, Second , Parity , Pregnancy , Risk Factors , Time Factors
9.
BJOG ; 114(3): 349-55, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17217358

ABSTRACT

OBJECTIVE: To assess whether the risk of severe blood loss is increased in semi-sitting and sitting position, and if so, to which extent blood loss from perineal damage is responsible for this finding. DESIGN: Secondary analysis of data from a large trial. SETTING: Primary care midwifery practices in the Netherlands. POPULATION: About 1646 low-risk women who had a spontaneous vaginal delivery. METHODS: Blood loss was measured using a weighing scale and measuring jug. Logistic regression analysis was used to examine the net effects of birthing position and perineal damage on blood loss greater than 500 ml. MAIN OUTCOME MEASURES: Mean total blood loss and incidence of blood loss greater than 500 ml and 1000 ml. RESULTS: Mean total blood loss and the incidence of blood loss greater than 500 ml and 1000 ml were increased in semi-sitting and sitting position. In logistic regression analysis, the interaction between birthing position and perineal damage was almost significantly associated with an increased risk of blood loss greater than 500 ml. Semi-sitting and sitting position were only significant risk factors among women with perineal damage (OR 1.30, 95% CI 1.00-1.69 and OR 2.25, 95% CI 1.37-3.71, respectively). Among women with intact perineum, no association was found. CONCLUSIONS: Semi-sitting and sitting birthing positions only lead to increased blood loss among women with perineal damage.


Subject(s)
Delivery, Obstetric/adverse effects , Perineum/injuries , Postpartum Hemorrhage/etiology , Posture , Adult , Age Factors , Birth Weight , Female , Hemoglobins/analysis , Humans , Pregnancy , Pregnancy Outcome , Regression Analysis , Risk Factors
10.
Analyst ; 129(10): 880-5, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15457314

ABSTRACT

Instrumentation used in infrared microspectroscopy (IR-MSP) permits the acquisition of spectra from samples as small as 100 pg (10(-10) g), and as small as 1 pg for Raman microspectroscopy (RA-MSP). This, in turn, allows the acquisition of spectral data from objects as small as fractions of human cells, and of small regions of microtome tissue sections. Since vibrational spectroscopy is exquisitely sensitive to the biochemical composition of the sample, and variations therein, it is possible to monitor metabolic processes in tissue and cells, and to construct spectral maps based on thousands of IR spectra collected from pixels of tissue. These images, in turn, reveal information on tissue structure, distribution of cellular components, metabolic activity and state of health of cells and tissue.


Subject(s)
Cell Physiological Phenomena , Microspectrophotometry/methods , Spectrophotometry, Infrared/methods , Computational Biology , Humans , Vibration
11.
Health Educ Res ; 19(4): 418-29, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15155595

ABSTRACT

How can women who are not yet pregnant be motivated to stop smoking before they become pregnant? Epidemiological studies have suggested that periconceptional smoking and smoking during the first trimester of the pregnancy may lead to congenital abnormalities. To motivate women to stop smoking before pregnancy, more insight is needed into the differences between 'smoking' women who want to have children and those who do not. A sample of 931 women (65% response rate) aged 15-45 years returned a questionnaire with questions about their smoking behavior, wish to have children, risk perceptions, attitude to smoking, personal efficacy and stage of readiness to change. In spite of some positive outcomes (e.g. negative attitude to smoking, relatively high risk perceptions of the relationship between congenital anomalies and smoking), one cannot automatically assume that these women will stop smoking before they get pregnant. (1) Beliefs, attitude and readiness to change were not well integrated and grounded cognitively. (2) Women who smoked were pessimistic about their ability to quit. Future campaigns need to 'invite' women to associate and to integrate risk information about the relationship between smoking and congenital abnormalities with other cognitions (attitude, intention). It is also important to instruct women in how to stop smoking and to remain non-smokers.


Subject(s)
Health Behavior , Smoking Cessation/psychology , Smoking/psychology , Adolescent , Adult , Female , Humans , Middle Aged , Pregnancy , Pregnancy Trimester, First/psychology , Self Efficacy , Self-Assessment , Surveys and Questionnaires
12.
Gynecol Oncol ; 93(1): 59-68, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15047215

ABSTRACT

OBJECTIVES: This paper is aimed at establishing infrared spectral patterns for the different tissue types found in, and for different stages of disease of squamous cervical epithelium. Methods for the unsupervised distinction of these tissue types are discussed. METHODS: Fourier transform infrared (FTIR) maps of the squamous and glandular cervical epithelium, and of the cervical transformation zone, were obtained and analyzed by multivariate unsupervised hierarchical cluster methods. The resulting clusters are correlated to the corresponding stained histopathological features in the tissue sections. RESULTS: Multivariate statistical analysis of FTIR spectra collected for tissue sections permit an unsupervised method of distinguishing tissue types, and of differentiating between normal and diseased tissue. By analyzing different spectral windows and comparing the results with histology, we found the amide I and II region (1740-1470 cm(-1)) to be very important in correlating anatomical and histopathological features in tissue to spectral clusters. Since an unsupervised, rather than a diagnostic, algorithm was used in these efforts, no statistical analysis of false-positive/false-negative results is reported at this time. CONCLUSIONS: The combination of FTIR micro-spectroscopy and multivariate spectral processing provides important insights into the fundamental spectral signatures of individual cells and consequently shows potential as a diagnostic tool for cervical cancer.


Subject(s)
Cell Transformation, Neoplastic/pathology , Cervix Uteri/cytology , Spectroscopy, Fourier Transform Infrared/methods , Uterine Cervical Dysplasia/pathology , Uterine Cervical Neoplasms/pathology , Epithelial Cells/cytology , Epithelial Cells/pathology , Female , Humans
13.
EMBO J ; 20(22): 6424-33, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11707413

ABSTRACT

The RNA-binding protein Y14 binds preferentially to mRNAs produced by splicing and is a component of a multiprotein complex that assembles approximately 20 nucleotides upstream of exon-exon junctions. This complex probably has important functions in post-splicing events including nuclear export and nonsense-mediated decay of mRNA. We show that Y14 binds to two previously reported components, Aly/REF and RNPS1, and to the mRNA export factor TAP. Moreover, we identified magoh, a human homolog of the Drosophila mago nashi gene product, as a novel component of the complex. Magoh binds avidly and directly to Y14 and TAP, but not to other known components of the complex, and is found in Y14-containing mRNPs in vivo. Importantly, magoh also binds to mRNAs produced by splicing upstream (approximately 20 nucleotides) of exon- exon junctions and its binding to mRNA persists after export. These experiments thus reveal specific protein-protein interactions among the proteins of the splicing-dependent mRNP complex and suggest an important role for the highly evolutionarily conserved magoh protein in this complex.


Subject(s)
Drosophila Proteins , Exons , Nuclear Proteins/metabolism , Nuclear Proteins/physiology , RNA Splicing , Animals , Cell Fractionation , Cell Line , Cell Nucleus/metabolism , Cytoplasm/metabolism , DNA, Complementary/metabolism , Drosophila , Evolution, Molecular , Glutathione Transferase/metabolism , HeLa Cells , Humans , Microscopy, Fluorescence , Models, Biological , Oocytes/metabolism , Plasmids/metabolism , Precipitin Tests , Protein Binding , Protein Structure, Tertiary , RNA, Messenger/metabolism , RNA-Binding Proteins , Recombinant Fusion Proteins/metabolism , Ribonuclease H/metabolism , Two-Hybrid System Techniques , Xenopus
14.
J Am Chem Soc ; 123(47): 11775-81, 2001 Nov 28.
Article in English | MEDLINE | ID: mdl-11716734

ABSTRACT

UV resonance Raman studies of peptide and protein secondary structure demonstrate an extraordinary sensitivity of the amide III (Am III) vibration and the C(alpha)H bending vibration to the amide backbone conformation. We demonstrate that this sensitivity results from a Ramachandran dihedral psi angle dependent coupling of the amide N-H motion to (C)C(alpha)H motion, which results in a psi dependent mixing of the Am III and the (C)C(alpha)H bending motions. The vibrations are intimately mixed at psi approximately 120 degrees, which is associated with both the beta-sheet conformation and random coil conformations. In contrast, these motions are essentially unmixed for the alpha-helix conformation where psi approximately -60 degrees. Theoretical calculations demonstrate a sinusoidal dependence of this mixing on the psi angle and a linear dependence on the distance separating the N-H and (C)C(alpha)H hydrogens. Our results explain the Am III frequency dependence on conformation as well as the resonance Raman enhancement mechanism for the (C)C(alpha)H bending UV Raman band. These results may in the future help us extract amide psi angles from measured UV resonance Raman spectra.


Subject(s)
Amides/chemistry , Protein Structure, Secondary , Proteins/chemistry , Models, Molecular , Peptides/chemistry , Polyglutamic Acid/chemistry , Protein Conformation , Spectrophotometry, Ultraviolet , Spectrum Analysis, Raman
15.
Comp Biochem Physiol C Toxicol Pharmacol ; 130(2): 209-18, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11574290

ABSTRACT

Tissue necrosis following spider bites is a widespread problem. In the continental United States, the brown recluse (Loxosceles reclusa), hobo spider (Tegenaria agrestis), garden spider (Argiope aurantia) and Chiracanthium species, among others, reportedly cause such lesions. The exact mechanism producing such lesions is controversial. There is evidence for both venom sphingomyelinase and spider digestive collagenases. We have examined the role of spider digestive proteases in spider bite necrosis. The digestive fluid of A. aurantia was assayed for its ability to cleave a variety of connective tissue proteins, including collagen. Having confirmed that the fluid has collagenases, the digestive fluid was injected into the skin of rabbits to observe whether it would cause necrotic lesions. It did not. The data do not support the suggestions that spider digestive collagenases have a primary role in spider bite necrosis.


Subject(s)
Endopeptidases/adverse effects , Skin/pathology , Spider Bites/pathology , Spider Venoms/adverse effects , Spiders/enzymology , Animals , Collagen/metabolism , Collagenases/metabolism , Connective Tissue/enzymology , Elastin/metabolism , Endopeptidases/chemistry , Endopeptidases/metabolism , Extracellular Matrix Proteins/metabolism , Female , Fibrin/metabolism , Hemolymph/metabolism , Molecular Weight , Necrosis , Rabbits
16.
EMBO J ; 20(8): 2062-8, 2001 Apr 17.
Article in English | MEDLINE | ID: mdl-11296238

ABSTRACT

We recently described an RNA-binding protein, Y14, that binds preferentially to spliced mRNAs and persists in the cytoplasm. Y14 is part of a multi-protein complex that also contains the mRNA export factor TAP. This suggests that splicing imprints the mRNA with a unique set of proteins that communicate the history of the transcript to the cytoplasm. Here, using microinjection of pre-mRNAs into Xenopus oocyte nuclei followed by immunoprecipitation of RNase-fragmented mRNAs from the cytoplasm, we show that Y14 is stably bound to sequences immediately upstream of exon-exon junctions. This feature appears to be unique to Y14. Using monoclonal antibodies that we produced against Aly/REF, another component recently reported to be an mRNA export factor, we show that Aly/REF is associated with spliced mRNAs in the nucleus but is not detectable on mRNAs in the cytoplasm. Thus, we propose that the splicing- dependent binding of Y14 provides a position-specific molecular memory that communicates to the cytoplasm the location of exon and intron boundaries. This novel mechanism may play an important role in post-splicing events.


Subject(s)
Cell Nucleus/metabolism , Cytoplasm/metabolism , Exons , RNA Splicing , RNA-Binding Proteins/metabolism , Active Transport, Cell Nucleus , Binding Sites , Models, Biological , Transcription Factors/metabolism
17.
Community Genet ; 4(4): 233-238, 2001 Jun.
Article in English | MEDLINE | ID: mdl-12107352

ABSTRACT

Objective: To describe and compare the information obstetricians and geneticists in five European countries report they would give following the prenatal diagnosis of Klinefelter syndrome. Methods: 388 obstetricians and 269 geneticists from Germany, the Netherlands, Portugal, Spain and the UK completed a brief questionnaire assessing two variables: the information they reported providing to parents following the prenatal diagnosis of Klinefelter syndrome (categorized as positive or negative); and their perceptions of the quality of life with the condition. Results: Geneticists were more likely than obstetricians to report providing more positive than negative information about Klinefelter syndrome than equal amounts of positive and negative information or more negative than positive information about the condition (excess positive information). Regardless of specialty, the information that health professionals reported providing was predicted by their perceptions of the quality of life with the condition, and the country from which they came. Those perceiving quality of life as greater were more likely to provide an excess positive information, as were health professionals from Germany and the UK. Conclusions: These results suggest that the information parents across Europe receive after the prenatal diagnosis of Klinefelter syndrome varies according to the specialty and country of the health professionals consulted, and their perceptions of quality of life with the condition. This variation seems to reflect personal, cultural and professional differences between health professionals. Copyright 2002 S. Karger AG, Basel

18.
Biopolymers ; 57(5): 282-90, 2000.
Article in English | MEDLINE | ID: mdl-10958320

ABSTRACT

Experimental and computational methods of infrared microspectroscopy (IRI-MSP) and infrared spectral mapping (ISM) are presented. These methods are subsequently applied to the analysis of cirrhotic liver tissue. The sensitivity of infrared spectral mapping toward spectral changes caused by disease will be demonstrated. In addition, the excellent agreement between ISM data and histopathological information will be discussed.


Subject(s)
Liver/chemistry , Liver/pathology , Humans , Image Processing, Computer-Assisted/methods , Liver Cirrhosis/pathology , Methods , Microspectrophotometry/methods , Spectroscopy, Fourier Transform Infrared/methods
19.
Antimicrob Agents Chemother ; 43(10): 2444-50, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10508022

ABSTRACT

AG7088 is a potent, irreversible inhibitor of human rhinovirus (HRV) 3C protease (inactivation rate constant (k(obs)/[I]) = 1,470,000 +/- 440,000 M(-1) s(-1) for HRV 14) that was discovered by protein structure-based drug design methodologies. In H1-HeLa and MRC-5 cell protection assays, AG7088 inhibited the replication of all HRV serotypes (48 of 48) tested with a mean 50% effective concentration (EC(50)) of 0.023 microM (range, 0.003 to 0.081 microM) and a mean EC(90) of 0.082 microM (range, 0.018 to 0.261 microM) as well as that of related picornaviruses including coxsackieviruses A21 and B3, enterovirus 70, and echovirus 11. No significant reductions in the antiviral activity of AG7088 were observed when assays were performed in the presence of alpha(1)-acid glycoprotein or mucin, proteins present in nasal secretions. The 50% cytotoxic concentration of AG7088 was >1,000 microM, yielding a therapeutic index of >12,346 to >333,333. In a single-cycle, time-of-addition assay, AG7088 demonstrated antiviral activity when added up to 6 h after infection. In contrast, a compound targeting viral attachment and/or uncoating was effective only when added at the initiation of virus infection. Direct inhibition of 3C proteolytic activity in infected cells treated with AG7088 was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of radiolabeled proteins, which showed a dose-dependent accumulation of viral precursor polyproteins and reduction of processed protein products. The broad spectrum of antiviral activity of AG7088, combined with its efficacy even when added late in the virus life cycle, highlights the advantages of 3C protease as a target and suggests that AG7088 will be a promising clinical candidate.


Subject(s)
Antiviral Agents/pharmacology , Cysteine Endopeptidases/drug effects , Isoxazoles/pharmacology , Pyrrolidinones/pharmacology , Rhinovirus/drug effects , Viral Proteins , 3C Viral Proteases , Cell Division/drug effects , Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/pharmacology , HeLa Cells , Humans , Microbial Sensitivity Tests , Phenylalanine/analogs & derivatives , Proteins/pharmacology , Rhinovirus/physiology , Serotyping , Valine/analogs & derivatives
20.
Biospectroscopy ; 5(4): 219-27, 1999.
Article in English | MEDLINE | ID: mdl-10478952

ABSTRACT

Infrared spectra of myeloid leukemia (ML-1) cells are reported for cells derived from an asynchronous, exponentially growing culture, as well as for cells that were fractionated according to their stage within the cell division cycle. The observed results suggest that the cells' DNA is detectable by infrared spectroscopy mainly when the cell is in the S phase, during the replication of DNA. In the G1 and G2 phases, the DNA is so tightly packed in the nucleus that it appears opaque to infrared radiation. Consequently, the nucleic acid spectral contributions in the G1 and G2 phases would be mostly that of cytoplasmic RNA. These results suggest that infrared spectral changes observed earlier between normal and abnormal cells may have been due to different distributions of cells within the stages of the cell division cycle.


Subject(s)
Cell Cycle , Leukemia, Myeloid/pathology , Spectrophotometry, Infrared/methods , Cell Division , DNA, Neoplasm/chemistry , G1 Phase , Humans , Tumor Cells, Cultured
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