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1.
Opt Express ; 32(2): 2235-2244, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38297758

ABSTRACT

With wavelength tunability, free-electron lasers (FELs) are well-suited for generating orbital angular momentum (OAM) beams in a wide photon energy range. We report here the first experimental demonstration of OAM beam generation using an oscillator FEL with the tens of picosecond pulse duration. Lasing around 458 nm, we have produced the four lowest orders of superposed Laguerre-Gaussian beams using a very long FEL resonator of 53.73 m. The produced beams have good beam quality, excellent stability, and substantial average power. We have also developed a pulsed operation mode for these beams with a highly reproducible temporal structure for a range of repetition rate of 1-30 Hz. This development can be extended to short wavelengths, for example to x-rays using a future x-ray FEL oscillator. The OAM operation of such a storage-ring FEL also paves the way for the generation of OAM gamma-ray beams via inverse Compton scattering.

2.
Phlebology ; 35(8): 550-555, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32639862

ABSTRACT

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semi-urgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/non-urgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.


Subject(s)
Coronavirus Infections/therapy , Decision Support Systems, Clinical/standards , Decision Support Techniques , Emergency Service, Hospital/standards , Lymphatic Diseases/therapy , Pneumonia, Viral/therapy , Triage/standards , Vascular Diseases/therapy , COVID-19 , Clinical Decision-Making , Consensus , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Health Services Needs and Demand/standards , Humans , Lymphatic Diseases/diagnosis , Lymphatic Diseases/epidemiology , Pandemics , Patient Selection , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Vascular Diseases/diagnosis , Vascular Diseases/epidemiology
3.
J Vasc Surg Venous Lymphat Disord ; 8(5): 706-710, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32426220

ABSTRACT

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semiurgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/nonurgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.


Subject(s)
Betacoronavirus , Coronavirus Infections/epidemiology , Lymphatic Diseases/therapy , Pneumonia, Viral/epidemiology , Triage/organization & administration , Vascular Diseases/therapy , Veins , COVID-19 , Consensus , Coronavirus Infections/diagnosis , Coronavirus Infections/prevention & control , Humans , International Cooperation , Lymphatic Diseases/diagnosis , Pandemics/prevention & control , Patient Selection , Pneumonia, Viral/diagnosis , Pneumonia, Viral/prevention & control , Reproducibility of Results , SARS-CoV-2 , Severity of Illness Index , Societies, Medical , Vascular Diseases/diagnosis , Vascular Surgical Procedures
7.
J Hypertens ; 26(5): 973-80, 2008 May.
Article in English | MEDLINE | ID: mdl-18398340

ABSTRACT

BACKGROUND: Few studies have directly compared the effects of different angiotensin receptor blockers (ARBs) on mechanisms involved in the pathogenesis of cardiovascular disease. METHODS: We studied the ability of different ARBs to inhibit the proliferation of vascular smooth muscle cells (VSMCs) and cardiac fibroblasts (CFs) in continuous culture and in quiescent cells stimulated to proliferate by platelet-derived growth factor (PDGF) and insulin. We also investigated whether the antiproliferative effects of ARBs depended on their ability to block angiotensin II receptors or activate the peroxisome proliferator-activated receptor gamma (PPAR gamma). RESULTS: Dose-response studies showed that candesartan, eprosartan, and irbesartan had little or no effect on the proliferation of VSMC or CF in continuous culture even when tested at concentrations as high as 10 mumol/l or when tested in cells stimulated with PDGF/insulin. In contrast, telmisartan inhibited VSMC and CF proliferation by 50-70% (P < 0.05) in a dose-dependent and reversible fashion and significantly inhibited the increases in cyclin D1 levels and cell proliferation induced by PDGF/insulin. Antiproliferative effects of telmisartan were also observed in Chinese hamster ovary (CHO-K1) cells that lack functional angiotensin II receptors and in human VSMCs treated with the PPAR gamma antagonist GW9662. CONCLUSION: Telmisartan, but not candesartan, irbesartan, or eprosartan, can significantly inhibit the proliferation of VSMC and CF in culture when tested at concentrations near those that can be achieved in plasma with usual oral dosing. Telmisartan can also inhibit the proliferation of cells that lack angiotensin II receptors and cells treated with a PPAR gamma antagonist suggesting that the antiproliferative effects of telmisartan may involve more than just angiotensin II receptor blockade or activation of PPAR gamma.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/pharmacology , Benzimidazoles/pharmacology , Benzoates/pharmacology , Cell Proliferation/drug effects , Fibroblasts/drug effects , Muscle, Smooth, Vascular/drug effects , Myocytes, Smooth Muscle/drug effects , Animals , Blood Pressure/drug effects , Cells, Cultured , Cyclin D1/drug effects , Dose-Response Relationship, Drug , Muscle, Smooth, Vascular/cytology , PPAR gamma/drug effects , Rats , Renin-Angiotensin System/drug effects , Telmisartan
8.
J Med Chem ; 49(14): 4072-84, 2006 Jul 13.
Article in English | MEDLINE | ID: mdl-16821769

ABSTRACT

A series of novel derivatives of potent antioxidant vitamin, alpha-lipoic acid, and related analogues were designed, synthesized, and evaluated for their PPARgamma agonist activities. Compounds 9a and the water soluble analogue11e were found to be potent PPARgamma agonists. Compound 9a appeared to have a significant role in improving insulin sensitivity and reducing triglyceride levels in fa/fa rats as well as inhibited proliferation of a variety of normal and neoplastic cultured human cell types. These novel compounds may prove efficacious not only in the treatment of Type 2 diabetes, but also atherosclerosis, prevention of vascular restenosis, and inflammatory skin diseases.


Subject(s)
Hypolipidemic Agents/chemical synthesis , PPAR gamma/agonists , Phenylacetates/chemical synthesis , Thiazolidinediones/chemical synthesis , Thioctic Acid/analogs & derivatives , Thioctic Acid/chemical synthesis , Adipocytes/cytology , Adipocytes/drug effects , Adipogenesis/drug effects , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Crystallography, X-Ray , Drug Design , Humans , Hypolipidemic Agents/pharmacology , Insulin Resistance , Interleukins/biosynthesis , Keratinocytes/cytology , Keratinocytes/drug effects , Models, Molecular , Molecular Structure , PPAR gamma/chemistry , Phenylacetates/pharmacology , Rats , Rats, Zucker , Structure-Activity Relationship , Thiazolidinediones/pharmacology , Thioctic Acid/pharmacology
9.
Psychosom Med ; 67(4): 584-9, 2005.
Article in English | MEDLINE | ID: mdl-16046371

ABSTRACT

OBJECTIVE: This prospective study assesses the roles of illness beliefs, emotion regulation factors, and sociodemographic characteristics in decisions to participate in a group support program for women recently diagnosed with breast cancer. METHOD: Women recruited during clinic visits 2 to 4 weeks after diagnosis completed measures of affective and cognitive factors identified by Leventhal's Common-Sense Model of illness self-regulation: cancer-related distress, avoidance tendencies, beliefs that the breast cancer was caused by stress and altered immunity, and personal control beliefs. Measures of general anxiety and depression, social support, and demographic characteristics were also completed; prognostic status information was obtained from medical records. All women were encouraged to participate in a free, 12-week program offering coping skills training and group support. Participation was recorded by program staff. RESULTS: Of the 110 women, 54 (49%) participated in the group support program and 56 (51%) did not. Logistic regression analyses revealed that participation was predicted by stronger beliefs that the cancer was caused by altered immunity, higher cancer-related distress, lower avoidance tendencies, and younger age. CONCLUSIONS: Participation in the group psychosocial support program appeared to be guided by cognitive and affective factors identified by the Common-Sense Model. Psychosocial support programs and informational materials promoting their use may attract more participants if they are tailored to focus on resolving cancer-related distress rather than on general anxiety or depression, appeal to those with high avoidance tendencies, address the role of immune function in cancer progression, and meet the needs of older participants.


Subject(s)
Breast Neoplasms/psychology , Breast Neoplasms/therapy , Patient Acceptance of Health Care , Social Support , Stress, Psychological/therapy , Adaptation, Psychological , Adult , Attitude to Health , Breast Neoplasms/complications , Decision Making , Emotions , Female , Humans , Middle Aged , Prospective Studies , Self-Help Groups , Socioeconomic Factors , Stress, Psychological/etiology , Stress, Psychological/psychology
10.
Exp Eye Res ; 80(3): 435-42, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15721625

ABSTRACT

PURPOSE: To determine the efficacy of the peroxisome proliferator-activated receptor gamma agonist, pioglitazone, in inhibiting corneal neovascularization. METHODS: Twenty-six adult male Sprague-Dawley rats were randomly divided into three groups. Each group received intrastromal polymer micropellets containing one of the following: Group 1, no active ingredient (n=10); Group 2, vascular endothelial growth factor (VEGF) (n=7); Group 3, VEGF and pioglitazone (n=9). Neovascularization was evaluated 7 days after pellet implantation. After systemic India ink injection, digital photographs of the eyes were taken. The area and density of neovascularization were measured using imaging software. RESULTS: Mean area of neovascularization was 0.43+/-0.18 mm2 for Group 1, 2.87+/-0.48 mm2 for Group 2 and 2.10+/-0.22 mm2 for Group 3. Statistical analysis showed significant differences between Groups 1 and 2 and Groups 1 and 3. There was no significant difference between Groups 2 and 3. Mean density of neovascularization was 2.16+/-0.66 for Group 1, 27.14+/-2.93 for Group 2 and 12.02+/-2.24 for Group 3. All comparisons between groups were statistically significant (P<0.01). CONCLUSIONS: Pioglitazone is effective in decreasing the density of angiogenesis in a VEGF-induced neovascular rat cornea model. There is possibility of even greater effect with higher doses of the drug. Pioglitazone is a promising drug for the treatment of ocular neovascularization.


Subject(s)
Corneal Neovascularization/prevention & control , Hypoglycemic Agents/pharmacology , PPAR gamma/pharmacology , Thiazolidinediones/pharmacology , Animals , Blotting, Western/methods , Cornea/chemistry , Cornea/drug effects , Cornea/pathology , Corneal Neovascularization/pathology , Ligands , Male , Microscopy, Phase-Contrast/methods , PPAR gamma/analysis , Pioglitazone , Rats , Rats, Sprague-Dawley , Vascular Endothelial Growth Factor A/pharmacology
12.
Arch Dermatol Res ; 296(3): 97-104, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15221328

ABSTRACT

Novel thiazolidinedione derivatives of the potent antioxidant, alpha-lipoic (thioctic, 1,2-dithiolane) acid, were prepared. The prototype N-(2-[4-[2,4-dioxo(1,3-thiazolidin-5-yl)methyl]phenoxy]ethyl)-5-(1,2-dithiolan-3-yl)- N-methylpentanamide (designated BP-1003), and dithioester derivatives thereof were shown to be potent activators of peroxisome proliferator-activated receptor gamma (PPARgamma) (EC(50) range 15-101 nM) and modest activators of PPARalpha (EC(50) 5 microM). Both the relatively hydrophobic dithiolane prototype, BP-1003, and its water-soluble dithioglycinate derivative, BP-1017, were shown to inhibit the proliferation of human keratinocytes and suppress the production of interleukin-2 by human peripheral lymphocytes to a greater extent than the antidiabetic thiazolidinedione, rosiglitazone. Both oral and topical administration of BP-1017 showed significant antiinflammatory effects in the oxazolone-sensitized mouse model of allergic contact dermatitis (ACD). These findings suggest that water-soluble lipoic acid-based thiazolidinediones may be efficacious as oral and topical agents for treating inflammatory skin conditions such as contact dermatitis, atopic dermatitis, and psoriasis.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Dermatitis, Allergic Contact/drug therapy , PPAR gamma/agonists , Thiazoles/pharmacology , Thioctic Acid/analogs & derivatives , Thioctic Acid/pharmacology , 3T3-L1 Cells , Adipocytes/cytology , Adipocytes/drug effects , Animals , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , Cell Division/drug effects , Disease Models, Animal , Haplorhini , Humans , Interleukin-2/metabolism , Keratinocytes/cytology , Keratinocytes/drug effects , Mice , PPAR gamma/metabolism , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , Thiazoles/chemistry , Thioctic Acid/chemistry
13.
Hypertension ; 43(5): 993-1002, 2004 May.
Article in English | MEDLINE | ID: mdl-15007034

ABSTRACT

The metabolic syndrome is a common precursor of cardiovascular disease and type 2 diabetes that is characterized by the clustering of insulin resistance, dyslipidemia, and increased blood pressure. In humans, mutations in the peroxisome proliferator-activated receptor-gamma (PPARgamma) have been reported to cause the full-blown metabolic syndrome, and drugs that activate PPARgamma have proven to be effective agents for the prevention and treatment of insulin resistance and type 2 diabetes. Here we report that telmisartan, a structurally unique angiotensin II receptor antagonist used for the treatment of hypertension, can function as a partial agonist of PPARgamma; influence the expression of PPARgamma target genes involved in carbohydrate and lipid metabolism; and reduce glucose, insulin, and triglyceride levels in rats fed a high-fat, high-carbohydrate diet. None of the other commercially available angiotensin II receptor antagonists appeared to activate PPARgamma when tested at concentrations typically achieved in plasma with conventional oral dosing. In contrast to ordinary antihypertensive and antidiabetic agents, molecules that can simultaneously block the angiotensin II receptor and activate PPARgamma have the potential to treat both hemodynamic and biochemical features of the metabolic syndrome and could provide unique opportunities for the prevention and treatment of diabetes and cardiovascular disease in high-risk populations.


Subject(s)
Angiotensin II Type 1 Receptor Blockers , Benzimidazoles/pharmacology , Benzoates/pharmacology , Receptors, Cytoplasmic and Nuclear/agonists , Transcription Factors/agonists , Adipocytes/drug effects , Animals , Benzimidazoles/chemistry , Benzoates/chemistry , Biphenyl Compounds/pharmacology , Blood Glucose/analysis , Cell Differentiation/drug effects , Cells, Cultured/drug effects , Chlorocebus aethiops , Drug Evaluation, Preclinical , Gene Expression Regulation/drug effects , Imidazoles/pharmacology , Insulin/blood , Irbesartan , Losartan/pharmacology , Male , Mice , Models, Molecular , Myoblasts/drug effects , Protein Conformation/drug effects , Rats , Rats, Sprague-Dawley , Receptors, Cytoplasmic and Nuclear/chemistry , Receptors, Cytoplasmic and Nuclear/genetics , Rosiglitazone , Structure-Activity Relationship , Telmisartan , Tetrazoles/pharmacology , Thiazoles/pharmacology , Thiazolidinediones/pharmacology , Thiazolidines , Transcription Factors/chemistry , Transcription Factors/genetics , Triglycerides/blood , Valine/analogs & derivatives , Valine/pharmacology , Valsartan , Weight Gain/drug effects
14.
J Invest Dermatol ; 122(1): 130-9, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14962101

ABSTRACT

This study was undertaken to evaluate the effects of thiazolidinediones (TZD) on keratinocyte proliferation, motility, and matrix metalloproteinase (MMP) production. Rosiglitazone (a potent TZD) inhibited both proliferation and motility as well as elaboration of MMP-1 and MMP-9. Inhibition was obtained with keratinocytes in monolayer culture and human skin in organ culture. There were significant concentration-response differences in sensitivity of the three keratinocyte responses to treatment with rosiglitazone. In contrast to keratinocytes, dermal fibroblasts were resistant to the effects of rosiglitazone. Treatment of keratinocytes with rosiglitazone did not suppress epidermal growth factor receptor autophosphorylation, but inhibited signaling through the extracellular regulated kinase mitogen-activated protein kinase pathway without a concomitant effect on pathways that lead to c-jun activation. Pioglitazone, another TZD, also suppressed keratinocyte proliferation, although it was less effective than rosiglitazone. An experimental TZD (BP-1107) inhibited keratinocyte proliferation at a much lower concentration than either rosiglitazone or pioglitazone. Because enhanced keratinocyte motility and increased MMP production as well as increased keratinocyte proliferation are thought to contribute to the phenotype of psoriatic lesional skin, we propose that interference with these keratinocyte responses contributes to the previously reported antipsoriatic activity of TZD.


Subject(s)
Hypoglycemic Agents/pharmacology , Keratinocytes/drug effects , Matrix Metalloproteinase 1/metabolism , Matrix Metalloproteinase 9/metabolism , Thiazolidinediones/pharmacology , Adult , Cell Division/drug effects , Cell Movement/drug effects , Cells, Cultured , Epidermal Cells , Fibroblasts/cytology , Fibroblasts/drug effects , Humans , Keratinocytes/cytology , Keratinocytes/enzymology , Organ Culture Techniques , Pioglitazone , Psoriasis/physiopathology , Rosiglitazone , Signal Transduction/drug effects
15.
Transplantation ; 73(1): 93-100, 2002 Jan 15.
Article in English | MEDLINE | ID: mdl-11792986

ABSTRACT

BACKGROUND: A reduction in acute rejection may reduce graft losses from chronic rejection, benefiting the recipient and helping ease the huge donor organ shortfall in the UK. The prediction of recipients at greater risk of acute rejection might justify the administration to them of more potent immunosuppression, but defining this group on clinical parameters has been largely unsuccessful. Events impacting on the kidney by the time of donation may, if detectable histologically, predict those kidneys more likely to undergo rejection. METHODS: A prospective immunohistochemical analysis was undertaken to detect P-Selectin (PS), E-Selectin (ES), platelets, leukocyte common antigen, macrophages, T cells, and neutrophils in the pretransplant biopsies of 77 adult renal transplant recipients. Twenty-nine (38%) of this group rejected. RESULTS: A significantly increased number of recipients rejected if the donor biopsy was PS positive (63 vs. 24%, P=0.0007), contained five or more leukocytes/glomerulus (48 vs. 21%, P=0.03), contained >9.3 leukocytes/high power field (46.5 vs. 10.5%, P=0.006) or was both PS positive and contained >9.3 leukocytes/high power field (61.9 vs. 0.0%, P=0.0001). The PS was mostly of platelet origin and the majority of leukocytes were macrophages. Only previous CMV or any current infection in the donor correlated with the immunohistochemical changes. CONCLUSIONS: These immuno-histochemical changes are present before transplantation, which allows the prediction of recipients at both a higher and a lower risk of acute rejection, enabling the administration of recipient tailored immunosuppression, and supports the use of additional therapeutic intervention to reduce the injury response both within the recipient and the donor.


Subject(s)
Graft Rejection/pathology , Kidney Transplantation/pathology , Leukocyte Count , Macrophages/pathology , Platelet Count , Adult , Age Factors , Analysis of Variance , Blood Platelets/pathology , Cell Adhesion Molecules/analysis , E-Selectin/analysis , Graft Rejection/blood , Graft Rejection/epidemiology , Humans , Immunohistochemistry , Kidney Cortex/pathology , Kidney Glomerulus/pathology , Leukocyte Common Antigens/analysis , Leukocytes/pathology , Middle Aged , P-Selectin/analysis , Predictive Value of Tests , Risk Factors , Transplantation, Homologous
16.
Wilehm Roux Arch Dev Biol ; 186(1): 65-70, 1979 Mar.
Article in English | MEDLINE | ID: mdl-28305312

ABSTRACT

Collagen fibrils with a main period banding of 610 Å and 220 Å in width were observed in the blastocoel of 72-h embryos of the sea urchin,Strongylocentrotus purpuratus. Non-striated fibrils of 50 Å diameter were also observed. The collagen is seen in highest concentration in the vicinity of mesenchyme cells which are richly endowed with endoplasmic reticulum and secretory vesicles. A role for collagen in cell attachment, orientation and spicule formation is discussed.

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