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El-Ghorr AA, Williams RM, Heap C, Norval M. Transcutaneous immunisation with herpes simplex virus stimulates immunity in mice. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 2000; 29:255-61. [PMID: 11118905 DOI: 10.1111/j.1574-695x.2000.tb01531.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herpes simplex virus (HSV) is common throughout the world and is a target for vaccine development. Transcutaneous immunisation is a novel technique that uses the application of vaccine antigens in solution on the skin in the presence of cholera toxin (CT) as an adjuvant. This study investigated the potential of transcutaneous immunisation in C3H mice, using CT co-administered with whole inactivated HSV-1 (CT+HSVi) or HSV-1 antigens extracted from infected Vero cells (CT+HSVag) or a control protein (CT+BSA). The application of any of the three vaccines on to bare mouse skin resulted in the migration of Langerhans cells from the epidermis and in the production of serum antibodies to CT. Both HSV preparations generated serum and mucosal (faecal) antibodies to HSV, with the CT+HSVi vaccine being a more potent stimulator of humoral immunity. The CT+HSVag vaccine, however, was the more potent stimulator of cell-mediated immunity, giving rise to a strong delayed type hypersensitivity response and lymphocyte proliferation in vitro. When the mice were challenged by epidermal inoculation of HSV, the CT+HSVag vaccine induced a higher level of protection than the CT+HSVi vaccine, a result which may indicate that the efficacy of HSV vaccines depends on stimulation of cell-mediated rather than humoral responses. The success of topical vaccination suggests that the transcutaneous route may offer a promising potential for novel vaccine delivery which merits further investigation.
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MESH Headings
- Adjuvants, Immunologic
- Administration, Cutaneous
- Animals
- Antibodies, Viral/analysis
- Antibodies, Viral/blood
- Antigens, Viral/administration & dosage
- Antigens, Viral/immunology
- B-Lymphocytes/immunology
- Cholera Toxin/immunology
- Herpes Simplex/immunology
- Herpes Simplex/prevention & control
- Herpes Simplex Virus Vaccines/administration & dosage
- Herpes Simplex Virus Vaccines/immunology
- Herpesvirus 1, Human/immunology
- Humans
- Hypersensitivity, Delayed
- Immunity, Mucosal
- Langerhans Cells/physiology
- Lymphocyte Activation
- Mice
- Mice, Inbred C3H
- T-Lymphocytes/immunology
- Vaccination
- Vaccines, Inactivated/immunology
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Vázquez A, Williams RM. Studies on the biosynthesis of taxol. Synthesis Of taxa-4(20), 11(12)-diene-2alpha,5alpha-diol. J Org Chem 2000; 65:7865-9. [PMID: 11073592 DOI: 10.1021/jo005537+] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of taxa-4(20),11(12)-diene-2alpha,5alpha-diol is described. An improved procedure for the intramolecular Diels-Alder cycloaddition previously reported in our synthesis of taxa-4(5), 11(12)-diene has been utilized to prepare a taxoid with oxygenation in the B and C rings. It has been established previously that taxa-4(20),11(12)-dien-5alpha-ol is the first oxygenated intermediate on the biosynthetic pathway to Taxol. Taxa-4(20), 11(12)-diene-2alpha,5alpha-diol (5), which has been observed in a biosynthetic conversion, is a potential candidate as the second oxygenated intermediate on the Taxol biosynthetic pathway, has been prepared to probe the intermediacy of this substance.
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Abstract
The pH cycling of individual granules in secreting (serotonin-loaded) mast cells is quantitatively examined using multicolor multiphoton fluorescence microscopy. A typical exocytosis event consists of maximal calcium rise at time zero, granule alkalization a few seconds later and, finally, complete contents release at a fraction of a second after alkalization. Membrane fusion is either transient, as indicated by subsequent granule reacidification, or ‘full’, as indicated by a granule disappearance with a collapse of its membrane into the plasma membrane. The relative frequency of these two coexisting behaviors (the ‘kiss-to-collapse’ ratio) is approximately 2:1. A typical transiently fusing granule experiences multiple alkalization/acidification cycles after addition of exogenous antigen. Between recycling granules, coalescence events are frequent, with 80% resulting in a collapse of the formed granule complex to the plasma membrane. The full dynamics of secretion encompass a complex combination of these granule activities.
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Sanz-Cervera JF, Stocking EM, Usui T, Osada H, Williams RM. Synthesis and evaluation of microtubule assembly inhibition and cytotoxicity of prenylated derivatives of cyclo-L-Trp-L-Pro. Bioorg Med Chem 2000; 8:2407-15. [PMID: 11058035 DOI: 10.1016/s0968-0896(00)00171-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The synthesis of three isoprenylated derivatives of cyclo-L-Trp-L-Pro is described. These substances have been evaluated for cytotoxic activity in rat normal fibroblast 3Y1 cells and have also been evaluated in vitro for the inhibition of microtubule assembly.
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Rose A, Lee RJ, Williams RM, Thomson LC, Forsyth A. Functional instability in non-contact ankle ligament injuries. Br J Sports Med 2000; 34:352-8. [PMID: 11049145 PMCID: PMC1756237 DOI: 10.1136/bjsm.34.5.352] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVES To measure objectively functional standing balance in the acute stages of non-contact ankle sprain, and to compare patients with controls. METHODS A Chattanooga balance machine was used to measure postural stability in patients with acute ankle sprain and uninjured controls over a two week period, in one and two legged stance, with eyes open and closed. Participants also completed the Olerud and Molander questionnaire to provide a subjective measure of ankle function. RESULTS There was a highly significant improvement in questionnaire scores for the patients during the study period (p<0.0001). Patients appeared to be less stable than controls in all balance tests, although the difference did not reach significance. There was evidence of improvement over time in the number of tests successfully completed on the injured leg in single legged stance with eyes closed (p = 0.043) between visits 1 and 3. CONCLUSIONS The patient group showed a subjective improvement, which supports clinical experience of treating acute ankle injuries. There is some evidence that on average the patient group appeared to be less stable than controls in all balance tests, although the difference did not reach statistical significance, even on the uninjured leg. There is a need to carry out further studies to confirm the results found in this pilot study and to investigate the hypotheses generated. It would be useful to evaluate a simple test that could be used clinically to monitor progress after ankle injury, and also to identify athletes with decreased functional stability, who may be more at risk of sustaining ankle injury.
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Beckerbauer L, Tepe JJ, Cullison J, Reeves R, Williams RM. FR900482 class of anti-tumor drugs cross-links oncoprotein HMG I/Y to DNA in vivo. CHEMISTRY & BIOLOGY 2000; 7:805-12. [PMID: 11033083 DOI: 10.1016/s1074-5521(00)00028-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Overexpression of the high-mobility group, HMG I/Y, family of chromatin oncoproteins has been implicated as a clinical diagnostic marker for both neoplastic cellular transformation and increased metastatic potential of several human cancers. These minor groove DNA-binding oncoproteins are thus an attractive target for anti-tumor chemotherapy. FR900482 represents a new class of anti-tumor agents that bind to the minor groove of DNA and exhibit greatly reduced host toxicity compared to the structurally related mitomycin C class of anti-tumor drugs. We report covalent cross-linking of DNA to HMG I/Y by FR900482 in vivo which represents the first example of a covalent DNA-drug-protein cross-link with a minor groove-binding oncoprotein and a potential novel mechanism through which these compounds exert their anti-tumor activity. RESULTS Using a modified chromatin immunoprecipitation procedure, fragments of DNA that have been covalently cross-linked by FR900482 to HMG I/Y proteins in vivo were polymerase chain reaction-amplified, isolated and characterized. The nuclear samples from control cells were devoid of DNA fragments whereas the nuclear samples from cells treated with FR900482 contained DNA fragments which were cross-linked by the drug to the minor groove-binding HMG I/Y proteins in vivo. Additional control experiments established that the drug also cross-linked other non-oncogenic minor groove-binding proteins (HMG-1 and HMG-2) but did not cross-link major groove-binding proteins (Elf-1 and NFkappaB) in vivo. Our results are the first demonstration that FR900482 cross-links a number of minor groove-binding proteins in vivo and suggests that the cross-linking of the HMG I/Y oncoproteins may participate in the mode of efficacy as a chemotherapeutic agent. CONCLUSIONS We have illustrated that the FR class of anti-tumor antibiotics, represented in this study by FR900482, is able to produce covalent cross-links between the HMG I/Y oncoproteins and DNA in vivo. The ability of this class of compounds to cross-link the HMG I/Y proteins in the minor groove of DNA represents the first demonstration of drug-induced cross-linking of a specific cancer-related protein to DNA in living cells. We have also demonstrated that FR900482 cross-links other minor groove-binding proteins (HMG-1 and HMG-2 in the present study) in vivo; however, since HMG I/Y is the only minor groove-binding oncoprotein presently known, it is possible that these non-histone chromatin proteins are among the important in vivo targets of this family of drugs. These compounds have already been assessed as representing a compelling clinical replacement for mitomycin C due to their greatly reduced host toxicity and superior DNA interstrand cross-linking efficacy. The capacity of FR900482 to cross-link the HMG I/Y oncoprotein with nuclear DNA in vivo potentially represents a significant elucidation of the anti-tumor efficacy of this family of anticancer agents.
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Nightingale J, Williams RM. Attitudes to emotional expression and personality in predicting post-traumatic stress disorder. BRITISH JOURNAL OF CLINICAL PSYCHOLOGY 2000; 39:243-54. [PMID: 11033747 DOI: 10.1348/014466500163266] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVES To test hypotheses derived from a suggestion of Williams (1989) that negative attitudes towards emotional expression act as a predisposing or maintaining factor for post-traumatic stress reactions following a traumatic event. DESIGN The study employed a prospective design in which attitudes to emotional expression, the 'Big Five' personality factors (Costa & McCrae, 1992a) and initial symptoms and injury severity within 1 week of a road traffic accident were used to predict the development of post-traumatic stress disorder 6 weeks post-accident. METHOD Sixty victims of road traffic accidents randomly selected from attenders at a large A&E department were assessed by questionnaire and interview. Measures comprised a 4-item scale relating to emotional expression, standardized scales for intrusion and avoidance features of traumatic experiences, and for anxiety and depression and the NEO-FFI Five Factor Personality Inventory. Forty-five of these participants responded to a postal questionnaire follow-up. In this survey the battery was repeated and also included a self-report diagnostic measure of post-traumatic stress disorder (PTSD). RESULTS The percentage of the sample meeting DSM-IV diagnostic criteria for PTSD at 6 weeks post-trauma was 30.8%. A small but significant relationship was found for negative attitudes to emotional expression at 1 week to predict intrusive symptoms and diagnosis at 6 weeks, over and above the independent relationships of initial symptoms, initial injury severity, personality and coping. The emotional expression measure was largely stable between the two points of measurement. More negative attitudes to emotional expression were related to less openness, extraversion and agreeableness personality domains. CONCLUSIONS Some support for the hypotheses was found in relation to the development of PTSD and for the status of attitudes to emotion as a stable trait related to personality factors. The potential importance of attitudes to emotional expression in therapy and other work is discussed.
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Williams RM, Cao J, Tsujishima H. Asymmetric, Stereocontrolled Total Synthesis of Paraherquamide A This work was supported by the NIH (Grant CA 70375). The Japanese Society for the Promotion of Science (JSPS) is acknowledged for providing support to H.T. Mass spectra were obtained on instruments supported by the NIH Shared Instrumentation Grant (GM 49631). We also wish to thank Dr. Timothy Blizzard (Merck & Co.) for providing an authentic sample of natural paraherquamide A. We also wish to acknowledge Dr. Byung H. Lee (Pharmacia-Upjohn Co.) for providing NMR spectra and an authentic specimen of 14-oxoparaherquamide B. We also wish to thank Dr. Alfredo Vazquez for assistance with purification and characterization of synthetic paraherquamide A. Angew Chem Int Ed Engl 2000; 39:2540-2544. [PMID: 10941129 DOI: 10.1002/1521-3773(20000717)39:14<2540::aid-anie2540>3.0.co;2-r] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
Congenital absence of the breast is a rare condition. The literature shows that there is much heterogeneity in its presentation as well as its inheritance. We described a mother and daughter with the condition and how the mother underwent breast reconstruction with use of bilateral transverse rectus abdominis myocutaneous flaps.
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Watkins E, Teasdale JD, Williams RM. Decentring and distraction reduce overgeneral autobiographical memory in depression. Psychol Med 2000; 30:911-920. [PMID: 11037099 DOI: 10.1017/s0033291799002263] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Increased recall of categorical autobiographical memories is a phenomenon unique to depression and post-traumatic stress disorder, and is associated with a poor prognosis for depression. Although the elevated recall of categorical memories does not change on remission from depression, recent findings suggest that overgeneral memory may be reduced by cognitive interventions and maintained by rumination. This study tested whether cognitive manipulations could influence the recall of categorical memories in dysphoric participants. METHODS Forty-eight dysphoric and depressed participants were randomly allocated to rumination or distraction conditions. Before and after the manipulation, participants completed the Autobiographical Memory Test, a standard measure of overgeneral memory. Participants were then randomized to either a 'decentring' question (Socratic questions designed to facilitate viewing moods within a wider perspective) or a control question condition, before completing the Autobiographical Memory Test again. RESULTS Distraction produced significantly greater decreases in the proportion of memories retrieved that were categorical than rumination. Decentring questions produced significantly greater decreases in the proportion of memories retrieved that were categorical than control questions, with this effect independent of the prior manipulation. CONCLUSIONS Elevated categorical memory in depression is more modifiable than has been previously assumed; it may reflect the dynamic maintenance of a cognitive style that can be interrupted by brief cognitive interventions.
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Williams RM, Petre R, Chu YH, Chen C. Resolving SNR 0540-6944 from LMC X-1 with Chandra. THE ASTROPHYSICAL JOURNAL 2000; 536:L27-L30. [PMID: 10849412 DOI: 10.1086/312729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2000] [Accepted: 05/03/2000] [Indexed: 05/23/2023]
Abstract
We examine the supernova remnant SNR 0540-697 in the Large Magellanic Cloud (LMC) using data from the Chandra Advanced CCD Imaging Spectrometer. The X-ray emission from this supernova remnant (SNR) had previously been hidden in the bright emission of the nearby X-ray binary LMC X-1; however, new observations with Chandra can finally reveal the SNR's structure and spectrum. We find the SNR to be a thick-shelled structure about 19 pc in diameter, with a brightened northeast region. Spectral results suggest a temperature of 0.31 keV and an X-ray luminosity (0.3-3.0 keV) of 8.4x1033 ergs s(-1). We estimate an age of 12,000-20,000 yr for this SNR, but note that this estimate does not take into account the possibility of cavity expansion or other environmental effects.
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Rajski SR, Williams RM. Observations on the covalent cross-linking of the binding domain (BD) of the high mobility group I/Y (HMG I/Y) proteins to DNA by FR66979. Bioorg Med Chem 2000; 8:1331-42. [PMID: 10896111 DOI: 10.1016/s0968-0896(00)00078-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
FR66979, a drug closely related to the mitomycin C class of antitumor antibiotics, is shown to covalently cross-link DNA to the DNA-binding domain of the High Mobility Group I/Y (HMG I/Y) DNA-binding proteins in the minor groove.
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Moy RL, Williams RM. Statistical report for 1999. Dermatol Surg 2000; 26:173. [PMID: 10759787 DOI: 10.1046/j.1524-4725.2000.00901.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Herberich B, Scott JD, Williams RM. Synthesis of a netropsin conjugate of a water-soluble epi-quinocarcin analogue: the importance of stereochemistry at nitrogen. Bioorg Med Chem 2000; 8:523-32. [PMID: 10732968 DOI: 10.1016/s0968-0896(99)00314-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The efficient synthesis of a water-soluble C11a-epi-analogue (6b) of quinocarcin is described. This substance, and a netropsin amide conjugate (8) lack the capacity to inflict oxidative damage on DNA due to the stereoelectronic geometry of their oxazolidine nitrogen atoms. The capacity of these substances to alkylate DNA through the generation of an iminium species has been examined. Both compounds were found to be unreactive as DNA alkylating agents. The results of this study are discussed in the context of previous proposals on the mode of action of this family of antitumor alkaloids.
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Williams RM, Kelly JF, Hartman JS, Sharpe SW, Taubman MS, Hall JL, Capasso F, Gmachl C, Sivco DL, Baillargeon JN, Cho AY. Kilohertz linewidth from frequency-stabilized mid-infrared quantum cascade lasers. OPTICS LETTERS 1999; 24:1844-1846. [PMID: 18079950 DOI: 10.1364/ol.24.001844] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Frequency stabilization of mid-IR quantum cascade (QC) lasers to the kilohertz level has been accomplished by use of electronic servo techniques. With this active feedback, an 8.5-microm QC distributed-feedback laser is locked to the side of a rovibrational resonance of nitrous oxide (N(2) O) at 1176.61cm (-1) . A stabilized frequency-noise spectral density of 42Hz/ radicalHz has been measured at 100 kHz; the calculated laser linewidth is 12 kHz.
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Tepe JJ, Williams RM. Reductive Activation of a Hydroxylamine Hemiacetal Derivative of Dehydromonocrotaline: The First Reductively Activated Pyrrolizidine Alkaloid Capable of Cross-Linking DNA. Angew Chem Int Ed Engl 1999; 38:3501-3503. [PMID: 10602221 DOI: 10.1002/(sici)1521-3773(19991203)38:23<3501::aid-anie3501>3.0.co;2-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The acute hepatotoxicity displayed by the pyrrolizidine alkaloids, which obviates their clinical utility, is a result of activation in vivo by cytochrome P450 mediated oxidation. Now the first reductively activated progenitor of the highly cytotoxic dehydropyrrolizidine alkaloid dehydromonocrotaline has been synthesized and demonstrated to mediate interstrand DNA cross-link formation (see scheme); pyrrolizidine alkaloids exert their cytotoxicity through the formation of DNA-DNA interstrand and DNA-protein cross-links.
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Williams RM, Gladstone HB, Moy RL. Hair removal using an 810 nm gallium aluminum arsenide semiconductor diode laser: A preliminary study. Dermatol Surg 1999; 25:935-7. [PMID: 10594625 DOI: 10.1046/j.1524-4725.1999.99174.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Laser hair removal is a popular treatment method for removing unwanted hair. Several laser systems are available for laser hair removal. The gallium aluminum arsenide semiconductor diode (GAASD) laser is one of the newer laser modalities to be studied. OBJECTIVE To evaluate the efficacy of the GAASD laser system in removing unwanted hair. METHODS Twenty-six patients with brown or black hair growth were treated with the GAASD laser at fluences of 20-80 J/cm2. Hair regrowth was measured 4 weeks after the first treatment, 4 weeks after the second treatment, 4 weeks after the third treatment, and 4 weeks, 8 weeks, and 8 months after the fourth treatment. CONCLUSION GAASD laser treatment resulted in hair growth delay in all treated regions. Repeated laser treatments did not produce an increased number of vellus hairs. The percentage of hair reduction fluctuated between 5% and 13% with the second or third treatment averaging the highest percent reduction. In all cases, the percentage of hair reduction of the treatment sites evaluated at 8 months after the fourth treatment was less than both the second and third treatments (highest average percent reduction) and the fourth (last) treatment.
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Denton DA, Blair-West JR, McBurnie MI, Miller JA, Weisinger RS, Williams RM. Effect of adrenocorticotrophic hormone on sodium appetite in mice. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:R1033-40. [PMID: 10516242 DOI: 10.1152/ajpregu.1999.277.4.r1033] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A main vector of the effects of stress is secretion of corticotrophin releasing factor (CRF), adrenocorticotrophin (ACTH), and adrenal steroids. Systemic administration of ACTH (2.8 microgram/day sc) for 7 days in BALB/c mice caused a very large increase of voluntary intake of 0.3 M NaCl equivalent to turnover of total body sodium content each day. Intracerebroventricular infusion of ACTH (20 ng/day) had no effect. Intracerebroventricular infusion of ovine CRF (10 ng/h for 7 days) caused an increase of sodium intake. The large sodium appetite-stimulating effect of systemic ACTH was not influenced by concurrent systemic infusion of captopril (2 mg/day). Induction of stress by immobilization of mice on a running wheel caused an increase in Na appetite associated with a 50% decrease of thymus weight, indicative of corticosteroid effects. The present data suggest that stress and the hormone cascade initiated by stress evoke a large sodium appetite in mice, which may be an important survival mechanism in environmental conditions causing stress.
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Menaker GM, Wrone DA, Williams RM, Moy RL. Treatment of facial rhytids with a nonablative laser: a clinical and histologic study. Dermatol Surg 1999; 25:440-4. [PMID: 10469089 DOI: 10.1046/j.1524-4725.1999.08158.x] [Citation(s) in RCA: 168] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Current facial resurfacing modalities (laser, chemical peels, and dermabrasion) remove the epidermis and thus cause open wounds which carry significant risks and extended recovery periods. The nonablative laser is a novel Nd:YAG system designed to alleviate facial rhytids without injuring the epidermis. This new modality may offer patients rhytid removal without the risk seen in currently used resurfacing techniques. OBJECTIVE To describe a novel nonablative laser system and assess its safety profile and efficacy. METHODS Ten patients received laser treatments of their periocular rhytids and postauricular skin. Clinical variables (rhytid severity, hyperpigmentation, hypopigmentation, scarring, and level of discomfort) were assessed at 1 and 3 months posttreatment. Postauricular skin biopsies were taken both pre- and posttreatment for histologic analysis. RESULTS Patient discomfort was minimal. Three months posttreatment, 4 of 10 patients showed a one-point improvement in periocular rhytid severity when judged on a six-point scale. The results were not statistically significant. Biopsy analysis showed a small posttreatment increase in the amount of dermal collagen in three patients. A small decrease in collagen was noted in one patient. Three patients also showed a small posttreatment increase in the degree homogenization of dermal collagen. No change from baseline was noted in other assessed histologic parameters. Complications observed included hyperpigmentation in three patients and pitted scarring in three patients. CONCLUSIONS The nonablative laser gave clinically subtle and statistically insignificant improvement in rhytid severity. Unfortunately its use was associated with complications that included hyperpigmentation and scarring. This technology may eventually offer patients a new resurfacing option, but its efficacy and complication rate must be improved first.
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Abstract
The long-pulsed ruby laser is a faster, more effective method for the removal of unwanted hair compared to older, temporary techniques like shaving, waxing, and chemical depilation. It is the only laser approved by the FDA for permanent hair removal. Patients experience minimal pain and side effects, observe immediate hair growth delay, an increase in vellus hairs, and have the potential for permanent hair removal. Although treatment sessions can be lengthy, the laser is easy to operate and the cooled handpiece allows patients to easily tolerate long sessions.
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Williams RM, Shear JB, Zipfel WR, Maiti S, Webb WW. Mucosal mast cell secretion processes imaged using three-photon microscopy of 5-hydroxytryptamine autofluorescence. Biophys J 1999; 76:1835-46. [PMID: 10096882 PMCID: PMC1300160 DOI: 10.1016/s0006-3495(99)77343-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The secretion process of the mucosal mast cell line RBL-2H3 was imaged using infrared three photon excitation (3PE) of serotonin (5-hydroxytryptamine, 5-HT) autofluorescence, a measurement previously difficult because of the technical intractability of deep UV optics. Images of prestimulation 5-HT distributions were analyzed in loaded cell populations (those incubated in a 5-HT-rich medium overnight) and in unloaded populations and were found to be strictly quantifiable by comparison with bulk population high-performance liquid chromatography measurements. Antigenically stimulated cells were observed to characteristically ruffle and spread as granular 5-HT disappeared with no detectable granule movement. Individual cells exhibited highly heterogeneous release kinetics, often with quasi-periodic bursts. Neighboring granule disappearances were correlated, indicative of either spatially localized signaling or granule-granule interactions. In one-half of the granule release events, weak residual fluorescence was visible suggestive of leftover 5-HT still bound to the granule matrix. The terminal stages of secretion (>300 s) consisted primarily of unresolved granules and remainder 5-HT leakage from already released granules.
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Bago B, Zipfel W, Williams RM, Piché Y. Nuclei of symbiotic arbuscular mycorrhizal fungi as revealed by in vivo two-photon microscopy. PROTOPLASMA 1999; 209:77-89. [PMID: 18987796 DOI: 10.1007/bf01415703] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/1998] [Accepted: 03/16/1999] [Indexed: 05/27/2023]
Abstract
The present work reports the results obtained from in vivo studies on the distribution and behavior of nuclei of two arbuscular mycorrhizal (AM) fungi growing in symbiosis with tomato root organ cultures (AM monoxenic cultures). Upon staining with 4',6-diamidino-2-phenylindole and two-photon microscopy (2PM) observations, symbiotic thick runner hyphae appeared mostly opaque to 2PM and did not reveal nuclei within them; thin runner hyphae showed dimly stained nuclei along them, whereas nuclei were clearly visible within the branches of the so-called branched absorbing structures. When visible, nuclei appeared anchored laterally at regular intervals along the symbiotic AM extraradical hyphae. Other nuclei migrate through the hyphal central core; this migration occurs in pulses. Simultaneous observations on different areas of extraradical AM mycelium revealed the existence of lysed compartments along the fungal hyphae, containing nuclei remnants and/or chromatin masses. All these results give new insights in (i) the differential permeability of AM hyphae in the symbiotic versus the asymbiotic state; (ii) the behavior and distribution of nuclei along the symbiotic extraradical mycelium; (iii) the occurrence of ageing events within the AM fungal colony; and (iv) the existence of "healing" mechanisms aiming to restrict the damage induced by such ageing or lytic events. An AM fungal strategy for hyphal survival under adverse conditions is also suggested.
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Williams RM. Pneumococcal vaccination. LIPPINCOTT'S PRIMARY CARE PRACTICE 1998; 2:625-33. [PMID: 9883157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Streptococcus pneumoniae community-acquired pneumonia (CAP) results in 40,000 deaths each year (Atkinson, 1997), making it the leading cause of death secondary to infection. Of these deaths, 50% could be prevented with the use of the pneumococcal vaccine. Developed 20 years ago, only 28% of patients 65 years and older receive the vaccine despite a prevention rate of invasive pneumococcal infections of 56-81% in immunocompetent adults. The overall cost for treating patients with CAP is more than $23 billion per year. More than $3.5 billion was spent on Medicare patients alone. Immunizing identified high-risk patients for CAP can improve morbidity and mortality rates for this group and ultimately reduce the amount of health care dollars spent on this preventable disease. Guidelines for identifying high-risk groups, a description of the vaccine, vaccination recommendations, and the signs and symptoms of CAP are discussed.
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Williams RM, McDonagh AF, Braslavsky SE. Structural volume changes upon photoisomerization of the bilirubin-albumin complex: a laser-induced optoacoustic study. Photochem Photobiol 1998; 68:433-7. [PMID: 9796429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The Z-->E photoisomerization of the 1:1 complexes of human serum albumin (HSA) and several bilirubins (BR-IX alpha, -III alpha, meso-IX alpha and a mixture of -IX alpha, -III alpha and XIII alpha) affords in every case an almost negligible structural volume change (delta VR approximately 0) within detection limits (i.e. less than 2-4 cm3/mol for this isomerization with very low quantum yield) as determined by laser-induced optoacoustic spectroscopy. Based on previous model studies of photoisomerizations in aqueous environment, this negligible small change is interpreted as indicating that the part of the molecule undergoing photoisomerization is not exposed to water but is located in a hydrophobic protein cavity that shields the molecule from the aqueous medium. The BR-protein interaction within this cavity seems to be very loose in view of the small structural volume change observed. The energy difference between the Z and E isomers of the BR-HSA complexes was estimated to be less than 4 kJ/mol, probably close to zero (delta H approximately 0).
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Xu K, Williams RM, Holowka D, Baird B. Stimulated release of fluorescently labeled IgE fragments that efficiently accumulate in secretory granules after endocytosis in RBL-2H3 mast cells. J Cell Sci 1998; 111 ( Pt 16):2385-96. [PMID: 9683633 DOI: 10.1242/jcs.111.16.2385] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sensitization of RBL-2H3 mast cells with monomeric fluorescein-5-isothiocyanate (FITC)-labeled immunoglobulin E (IgE) results in slow but highly efficient accumulation of labeled IgE fragments in a pool of acidic peripheral vesicles that are visible by fluorescence microscopy after raising endosomal pH with ammonium chloride. Stimulation of cells containing these FITC-IgE fragments by aggregation of high affinity receptors for IgE (FcepsilonRI) or by Ca2+ ionophore and phorbol 12-myristate 13-acetate results in release of FITC fluorescence from the cells, which can be monitored continuously with a spectrofluorometer. The fluorescence release process corresponds to cellular degranulation: it is prevented under conditions that prevent stimulated beta-hexosaminidase release, and these two processes exhibit the same antigen dose-dependence and kinetics. Pulse-chase labeling reveals that aggregation of FITC-IgE bound to FcepsilonRI at the cell surface causes internalization and delivery to the regulated secretory vesicles with a high efficiency similar to monomeric IgE-FcepsilonRI, but more rapidly. Binding of Cy3-modified IgE to FcepsilonRI results in labeling of the same secretory vesicles as in FITC-IgE-sensitized cells, and these Cy3-labeled vesicles can be observed by fluorescence microscopy without neutralization of intracellular compartments. Simultaneous three-photon microscopy of serotonin fluorescence and two-photon microscopy of Cy3 fluorescence reveals that these Cy3-labeled vesicles coincide with serotonin-labeled secretory granules. After stimulation of the cells via aggregation of IgE-FcepsilonRI or addition of Ca2+ ionophore and phorbol 12-myristate 13-acetate, depletion of the Cy3 label from the intracellular vesicles is observed with confocal microscopy. These results provide strong evidence for the lysosomal nature of secretory granules in these cells. In addition, they provide the basis for a direct, real-time method for monitoring single cell degranulation.
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Williams RM, Sanz-Cervera JF, Sancenón F, Marco JA, Halligan KM. Biomimetic Diels-Alder cyclizations for the construction of the brevianamide, paraherquamide, sclerotamide, asperparaline and VM55599 ring systems. Bioorg Med Chem 1998; 6:1233-41. [PMID: 9784865 DOI: 10.1016/s0968-0896(98)00102-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A potentially bio-mimetic Diels-Alder cyclization to construct the bicyclo[2.2.2] ring system common to the paraherquamides, marcfortines, sclerotamides, brevianamides, VM55599, and asperparaline is reported. Epi-deoxybrevianamide E (22) is converted into the corresponding lactim ether (23) and then oxidized with DDQ to provide an azadiene (24) which is tautomerized in the presence of base to azadiene 25 which, spontaneously cyclizes to give a 2:1 mixture of cycloadducts 26 and 27. These cycloadducts are each in turn, converted into D,L-C-19-epi-brevianamide A (20) and D,L-brevianamide B (6). The stereochemical implications of the [4 + 2] cycloaddition is discussed in the context of a working hypothesis on the biosynthesis of this family, particularly VM55599.
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Singh J, Williams RM, Lea RW, Adeghate E. Interaction between vasoactive intestinal polypeptide (VIP) and neuropeptide Y (NPY) in the isolated rat lacrimal gland. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 438:163-7. [PMID: 9634881 DOI: 10.1007/978-1-4615-5359-5_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Singh J, Sharkey KA, Lea RW, Williams RM. Effects of neuropeptides on serotonin release and protein and peroxidase secretion in the isolated rat lacrimal gland. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 438:145-51. [PMID: 9634878 DOI: 10.1007/978-1-4615-5359-5_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Williams RM, Myers AM. Functional Abilities Confidence Scale: a clinical measure for injured workers with acute low back pain. Phys Ther 1998; 78:624-34. [PMID: 9626274 DOI: 10.1093/ptj/78.6.624] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND PURPOSE The Functional Abilities Confidence Scale (FACS) measures self-confidence concerning various movements and postures affected by low back pain (LBP). This article describes the scale's development, based on qualitative themes suggested by clinicians and patients, and its psychometric properties. SUBJECTS People with work-related LBP injuries and clinicians from 8 different rehabilitation clinics participated in the study. METHODS A group of 20 subjects completed the FACS twice, about 2 days apart, for assessment of test-retest reliability. The FACS was also administered, together with other measures, to a separate group of 94 subjects at clinic entry and at discharge or 3 weeks after clinic entry for validity testing. Clinicians rated each subject's physical abilities at each point. RESULTS The FACS showed good psychometric properties (i.e., test-retest reliability, internal consistency, responsiveness to change, discriminant abilities, and convergent validity). CONCLUSION AND DISCUSSION The FACS is a measure that has potential use in guiding therapists in determining a person's initial level of confidence and in monitoring progress during the rehabilitation process.
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Williams RM, Myers AM. A new approach to measuring recovery in injured workers with acute low back pain: Resumption of Activities of Daily Living Scale. Phys Ther 1998; 78:613-23. [PMID: 9626273 DOI: 10.1093/ptj/78.6.613] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND PURPOSE Spontaneous recovery, job satisfaction, and multiple other factors make return to work a highly problematic indicator. Available client questionnaires fail to consider what was "normal" or "usual" prior to low back injury. Based on themes described by injured persons, we suggest a new approach to determining "recovery"--the Resumption of Activities of Daily Living (RADL) Scale. SUBJECTS Injured persons and their therapists from 8 different clinics participated in the study. METHODS Twenty subjects completed the RADL twice, about 2 days apart, for assessment of test-retest reliability. The RADL was administered, along with other questionnaires, to a separate group of 94 subjects at clinic entry and at discharge or 3 weeks after clinic entry. Both subjects and clinicians made baseline predictions concerning return to work and global ratings of improvement and ability to return to work at follow-up. RESULTS The RADL showed good psychometric properties (i.e., test-retest reliability, internal consistency, responsiveness to change, and discriminative abilities). CONCLUSION AND DISCUSSION The RADL provides a new, standardized measure for assessing the extent of recovery from the time of injury to initiation of treatment, and concurrent with the course of treatment, using the individual's customary level of functioning as the benchmark.
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McKay CP, Grunthaner FJ, Lane AL, Herring M, Bartman RK, Ksendzov A, Manning CM, Lamb JL, Williams RM, Ricco AJ, Butler MA, Murray BC, Quinn RC, Zent AP, Klein HP, Levin GV. The Mars oxidant experiment (MOx) for Mars '96. PLANETARY AND SPACE SCIENCE 1998; 46:769-777. [PMID: 11541819 DOI: 10.1016/s0032-0633(98)00011-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The MOx instrument was developed to characterize the reactive nature of the martian soil. The objectives of MOx were: (1) to measure the rate of degradation of organics in the martian environment; (2) to determine if the reactions seen by the Viking biology experiments were caused by a soil oxidant and measure the reactivity of the soil and atmosphere: (3) to monitor the degradation, when exposed to the martian environment, of materials of potential use in future missions; and, finally, (4) to develop technologies and approaches that can be part of future soil analysis instrumentation. The basic approach taken in the MOx instrument was to place a variety of materials composed as thin films in contact with the soil and monitor the physical and chemical changes that result. The optical reflectance of the thin films was the primary sensing-mode. Thin films of organic materials, metals, and semiconductors were prepared. Laboratory simulations demonstrated the response of thin films to active oxidants.
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DeLauro CR, Williams RM. Should congress legislate health care because health plans and providers cannot? ONS NEWS 1998; 13:8, 12. [PMID: 9582808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Free A, Williams RM, Dorman CJ. The StpA protein functions as a molecular adapter to mediate repression of the bgl operon by truncated H-NS in Escherichia coli. J Bacteriol 1998; 180:994-7. [PMID: 9473058 PMCID: PMC106983 DOI: 10.1128/jb.180.4.994-997.1998] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The mechanism of repression of the beta-glucoside utilization (bgl) operon of Escherichia coli by a carboxy-terminally truncated derivative of the nucleoid-associated protein H-NS which is defective in DNA binding was investigated. The DNA-binding function of the H-NS-like protein StpA was found to be necessary for repression, which is consistent with a role for StpA as a DNA-binding adapter for mutant derivatives of H-NS.
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Williams RM, Yuan C, Lee VJ, Chamberland S. Synthesis and antimicrobial evaluation of TAN-1057A/B analogs. J Antibiot (Tokyo) 1998; 51:189-201. [PMID: 9544941 DOI: 10.7164/antibiotics.51.189] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
TAN-1057A-D, dipeptides isolated from bacteria Flexibacter sp. PK-74 and PK-176, are new antibiotics with potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). We describe, in detail, the synthesis of several TAN-1057A/B analogs by a convergent route featuring a new method to construct the cyclic amidinourea functional group. The biological activity of these substances against methicillin-resistant Staphylococcus aureus (MRSA) is reported.
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Williams RM, Peterson CL. The Color of Memory: Interpreting Twentieth-Century U.S. Social Policy from a Nineteenth-Century Perspective. FEMINIST STUDIES 1998. [DOI: 10.2307/3178614] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Williams RM, Rimsky S. Molecular aspects of the E. coli nucleoid protein, H-NS: a central controller of gene regulatory networks. FEMS Microbiol Lett 1997; 156:175-85. [PMID: 9513262 DOI: 10.1111/j.1574-6968.1997.tb12724.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The nucleoid-associated protein H-NS has a central role in the structuring and control of the enteric bacterial chromosome. This protein has been demonstrated to contribute to the regulation of expression for approximately thirty genes. In this article, the molecular aspects of H-NS structure and function are briefly reviewed. H-NS contains at least two independent structural domains: a C-terminal domain, involved in the DNA-protein interactions, and a N-terminal domain, likely involved in protein-protein interactions. Recent reports have revealed that H-NS is a key factor in a multi-component gene regulatory system. Factors have now been discovered which can backup or antagonise H-NS action at certain promoters. These recent findings are summarised and discussed in relationship to the role of H-NS in DNA packaging and nucleoid structure.
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Williams RM, Berthoud HR, Stead RH. Vagal afferent nerve fibres contact mast cells in rat small intestinal mucosa. Neuroimmunomodulation 1997; 4:266-70. [PMID: 9650820 DOI: 10.1159/000097346] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Mast cells degranulate when exposed to specific antigens (via surface bound IgE), resulting in the release of numerous pro-inflammatory mediators. Neuroregulatory substances also activate mast cells, and may effect differential mediator release, without degranulation, suggesting a role for nerves in modulating mast cell activity. We previously investigated the microanatomical relationships of intestinal mucosal mast cells (IMMC) with nerves and found extensive associations in the intestinal mucosae of rats and humans. The origins of nerves that contact IMMC have not been determined; however, recent morphological and functional studies suggest the possibility that the vagus nerve might be involved. In the current study we show that vagal afferent fibers (labeled by injecting DiI into the nodose ganglion) penetrate to the tips of jejunal villi; and that some of these nerves make intimate contact with IMMC. These data provide the microanatomical basis for direct neural communication between the central nervous system (CNS) and mast cells in the gastrointestinal mucosa.
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Greenwood JE, Parry AD, Williams RM, McCollum CN. Trigger-fired pinch-graft harvester for use in chronic venous ulcers. Br J Surg 1997; 84:397-8. [PMID: 9117321 DOI: 10.1046/j.1365-2168.1997.02574.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Williams RM. Are poison control centers cost-effective? Ann Emerg Med 1997; 29:246-7. [PMID: 9018190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Williams RM, Rajski SR, Rollins SB. FR900482, a close cousin of mitomycin C that exploits mitosene-based DNA cross-linking. CHEMISTRY & BIOLOGY 1997; 4:127-37. [PMID: 9190287 DOI: 10.1016/s1074-5521(97)90256-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The class of antitumor antibiotics that includes FR900482 has a very close structural analogy to the mitomycins, one of which, mitomycin C, has been in widespread clinical use for more than 20 years. Like mitomycin C, these antitumor antibiotics are reductively activated in vivo and covalently cross-link DNA as a result of activity of the mitosene moiety generated on reduction. Owing to differences in structure and the attendant mechanistic differences in bioreductive activation between the mitomycins and FR900482, FR900482 does not produce an adventitious superoxide radical anion during reductive activation and thus does not exhibit oxidative strand scission of DNA. It is postulated that the low clinical toxicity of FR900482 relative to mitomycin C is a direct manifestation of the mechanistic differences of bioreductive activation leading to the highly reactive DNA cross-linking mitosenes. RESULTS Using Fe(II)-EDTA footprinting, we showed that the two natural products FR900482 (1) and dihydro, FR66979 (3), and the semi-synthetically derived triacetate FK973 (2), display remarkable selectivity for 5' deoxy-CG sequences of DNA, and that this selectivity is abolished upon deletion of the exocyclic N2 amine of either participating guanosine residue. In addition, we investigated the mono alkylation abilities of FR66979 with respect to a number of inosine-substituted oligonucleotides and observed that the FR900482 class of compounds were able to give rise to easily separable orientation isomers of their respective cross-links. CONCLUSIONS The FR900482 class of antitumor antibiotics cross-link DNA in a fashion analogous to the mitomycins. The cross-linking reaction yields two orientation isomers which are of vastly different electrophoretic mobility and which also exhibit radically different DNA-protein recognition properties upon reaction with AluI restriction endonuclease. In addition, mono-alkylation of DNA by FR66979 shows little, if any, dependence upon pre-covalent interactions deemed necessary for the mitomycins. These insights support the proposal that the FR900482 class of compounds represents a compelling clinical replacement for mitomycin C, given its greatly reduced host toxicity and superior DNA interstrand cross-linking efficacy.
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Maiti S, Shear JB, Williams RM, Zipfel WR, Webb WW. Measuring serotonin distribution in live cells with three-photon excitation. Science 1997; 275:530-2. [PMID: 8999797 DOI: 10.1126/science.275.5299.530] [Citation(s) in RCA: 347] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Tryptophan and serotonin were imaged with infrared illumination by three-photon excitation (3PE) of their native ultraviolet (UV) fluorescence. This technique, established by 3PE cross section measurements of tryptophan and the monoamines serotonin and dopamine, circumvents the limitations imposed by photodamage, scattering, and indiscriminate background encountered in other UV microscopies. Three-dimensionally resolved images are presented along with measurements of the serotonin concentration ( approximately 50 mM) and content (up to approximately 5 x 10(8) molecules) of individual secretory granules.
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Aghili H, Mushlin RA, Williams RM, Rose JS. Progress notes model. PROCEEDINGS : A CONFERENCE OF THE AMERICAN MEDICAL INFORMATICS ASSOCIATION. AMIA FALL SYMPOSIUM 1997:12-6. [PMID: 9357579 PMCID: PMC2233487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The largest part of the medical record today consists of notes documenting the care delivered to patients and the clinical events relevant to diagnosis and treatment. These "progress notes" serve as the repository of medical facts and clinical thinking, and are intended as a concise vehicle of communication about a patient's condition to those who access the health record. They should be readable, easily understood, complete, accurate, and concise. They must also be flexible enough to logically convey to others what happened during an encounter, e.g., the chain of events during the visit, as well as guaranteeing full accountability for documented material, e.g., who recorded the information and when it was recorded. This paper describes a model for progress notes, which addresses the above needs, and outlines the rationale and principles which led to that model.
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Abstract
STUDY OBJECTIVE To report the distribution of emergency department costs by category of expense and level of patient urgency. METHODS Cost-to-charge and relative-value methods were used to determine direct and indirect physician, facility, supply, pharmacy, laboratory, radiology, and miscellaneous costs for 24,010 ED patients. Explicit criteria were used to classify patient visits as nonurgent, semiurgent, or urgent. RESULTS For all patients, the average costs were physician, $64; facility, $84; laboratory, $21; radiology, $24, and total, $209. Laboratory and radiology costs accounted for 5% of the total costs for nonurgent visits and 23% of the total costs for urgent visits. CONCLUSION The distribution of ED costs varies significantly according to the urgency of the medical condition. For nonurgent patient visits, most costs are represented by the hospital facility and ED physicians' costs. Ancillary services represent a much greater proportion of costs for patients with urgent conditions. Although reduced test-ordering might result in some savings among patients with urgent conditions, overall improved cost efficiency can be achieved only through reductions in the fixed costs of operation of hospital EDs.
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Williams RM, Bauce L, Lea RW, Singh J, Sharkey KA. Secretion and serotonin release in the isolated rat lacrimal gland: the effects of substance P and calcitonin gene-related peptide. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1996; 61:37-42. [PMID: 8912252 DOI: 10.1016/0165-1838(96)00031-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A close anatomical relationship between nerves containing substance P and calcitonin gene-related peptide (CGRP) and mast cells containing serotonin has been demonstrated in the rat lacrimal gland. This study investigates the potential for peptidergic regulation of lacrimal mast cells by examining the actions of substance P, CGRP and serotonin on protein and peroxidase secretion from isolated lacrimal segments and on substance P and CGRP to release serotonin from the lacrimal mast cells. Substance P, CGRP and serotonin evoked marked increases in total protein and peroxidase from the lacrimal. Sodium cromoglycate, a mast cell stabilizer, significantly reduced or blocked the secretory responses elicited by these agonists. Chromatographic analysis using electrochemical detection revealed that substance P, but not CGRP, augmented the release of serotonin from the gland. The substance P evoked peroxidase secretion and serotonin release was blocked by CGRP and by sodium cromoglycate. These results support a role for mast cells in the regulation of lacrimal secretion and suggest a novel regulatory interaction between substance P and CGRP in the control of lacrimal function through a neuro-immune interaction.
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Xu C, Zipfel W, Shear JB, Williams RM, Webb WW. Multiphoton fluorescence excitation: new spectral windows for biological nonlinear microscopy. Proc Natl Acad Sci U S A 1996; 93:10763-8. [PMID: 8855254 PMCID: PMC38229 DOI: 10.1073/pnas.93.20.10763] [Citation(s) in RCA: 705] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Intrinsic, three-dimensionally resolved, microscopic imaging of dynamical structures and biochemical processes in living preparations has been realized by nonlinear laser scanning fluorescence microscopy. The search for useful two-photon and three-photon excitation spectra, motivated by the emergence of nonlinear microscopy as a powerful biophysical instrument, has now discovered a virtual artist's palette of chemical indicators, fluorescent markers, and native biological fluorophores, including NADH, flavins, and green fluorescent proteins, that are applicable to living biological preparations. More than 25 two-photon excitation spectra of ultraviolet and visible absorbing molecules reveal useful cross sections, some conveniently blue-shifted, for near-infrared absorption. Measurements of three-photon fluorophore excitation spectra now define alternative windows at relatively benign wavelengths to excite deeper ultraviolet fluorophores. The inherent optical sectioning capability of nonlinear excitation provides three-dimensional resolution for imaging and avoids out-of-focus background and photodamage. Here, the measured nonlinear excitation spectra and their photophysical characteristics that empower nonlinear laser microscopy for biological imaging are described.
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Williams RM, Rimsky S, Buc H. Probing the structure, function, and interactions of the Escherichia coli H-NS and StpA proteins by using dominant negative derivatives. J Bacteriol 1996; 178:4335-43. [PMID: 8755860 PMCID: PMC178199 DOI: 10.1128/jb.178.15.4335-4343.1996] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Twelve different dominant negative mutants of the Escherichia coli nucleoid-associated protein, H-NS, have been selected and characterized in vivo. The mutants are all severely defective in promoter repression activity in a strain lacking H-NS, and they all disrupt the repression normally exerted by H-NS at two of its target promoters. From the locations of the alterations in these mutants, which result in both large truncations and amino acid substitutions, we propose that H-NAS contains at least two distinct domains. The in vitro protein-protein cross-linking data presented in this report indicate that the proposed N-terminal domain of H-NS has a role in H-NS multimerization. StpA is a protein with known structural and functional homologies to H-NS. We have analyzed the extent of these homologies by constructing and studying StpA mutants predicted to be dominant negative. Our data indicate that the substitutions and deletions found in dominant negative H-NS have similar effects in the context of StpA. We conclude that the domain organizations and functions in StpA and H-NS are closely related. Furthermore, dominant negative H-NS can disrupt the activity of native StpA, and reciprocally, dominant negative StpA can disrupt the activity of native H-NS. We demonstrate that the N-terminal domain of H-NS can be chemically cross-linked to both full-length H-NS and StpA. We account for these observations by proposing that H-NS and StpA have the ability to form hybrid species.
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Hefner J, Rubenstein SM, Ketchum RE, Gibson DM, Williams RM, Croteau R. Cytochrome P450-catalyzed hydroxylation of taxa-4(5),11(12)-diene to taxa-4(20),11(12)-dien-5alpha-ol: the first oxygenation step in taxol biosynthesis. CHEMISTRY & BIOLOGY 1996; 3:479-89. [PMID: 8807878 DOI: 10.1016/s1074-5521(96)90096-4] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND The structural complexity of taxol dictates continued reliance on biological production methods, which may be improved by a detailed understanding of taxol biosynthesis, especially the rate-limiting steps. The biosynthesis of taxol involves the cyclization of the common isoprenoid intermediate geranylgeranyl diphosphate to taxa-4(5), 11(2)-diene followed by extensive, largely oxidative, modification of this diterpene olefin. We set out to define the first oxygenation step in taxol biosynthesis. RESULTS Microsomal enzymes from Taxus stem and cultured cells were used to define the first hydroxylation of taxadiene. We confirmed the structure of the reaction product (taxa-4(20), 11(12)-dien-5alpha-ol) by synthesizing this compound. The responsible biological catalyst was characterized as a cytochrome P450 (heme thiolate protein). In vivo studies confirmed that taxadienol is a biosynthetic intermediate and indicated that the hydroxylation step that produces this product is slow relative to subsequent metabolic transformations. CONCLUSIONS The structure of the first oxygenated intermediate on the taxol pathway establishes that the hydroxylation reaction proceeds with an unusual double bond migration that limits the mechanistic possibilities for subsequent elaboration of the oxetane moiety of taxol. The reaction is catalyzed by a cytochrome P450, suggesting that the seven remaining oxygenation steps in taxol biosynthesis may involve similar catalysts. Because the first oxygenation step is slow relative to subsequent metabolic transformations, it may be possible to speed taxol biosynthesis by isolating and manipulating the gene for the taxadiene-5-hydroxylase that catalyzes this reaction.
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