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1.
Jennifer C. Chen Katrina L. Schmid Brian Brown Marion H. Edwards Bibianna SY Yu John KF Lew 《Clinical & experimental optometry》2003,86(5):323-330
Purpose: Caucasian children with myopia have elevated response accommodative vergence to accommodation (AC/A) ratios. The purpose of this study was twofold: to determine if response AC/A ratios vary with refractive error and with myopic progression rate in Hong Kong Chinese children, and to determine the effect of beta‐adrenergic antagonism with topical timolol application on AC/A ratios. Methods: Thirty children aged eight to 12 years participated in the study. All refractive errors were corrected with spectacle lenses. Accommodative responses were measured using a Shin‐Nippon autorefractor and concurrent changes in vergence were assessed using a vertical prism and a Howell‐Dwyer card at three metres and 0.33 metre. Accommodative demand was altered using plus or minus two dioptre lenses and lens‐ and distance‐induced response AC/A ratios were calculated. Measurements were repeated 30 minutes after the instillation of topical timolol maleate (0.5 per cent). Results: AC/A ratios appeared higher in progressing myopic children but the difference was not statistically significant. Timolol application reduced accommodative convergence (AC) in the stable myopes (reduction = ‐3 ± 1.14A) but not in the emmetropes (0.69 ± 0.9P) or progressing myopes (0.16 ± 0.43A) and this difference between refractive groups was statistically s ignificant (F2,27= 3.766; P= 0.036). However, timolol did not produce a significant change in the accommodative response to positive or negative lenses or response AC/A ratios. Conclusions: We did not find that AC/A ratios in myopic Chinese children were elevated and therefore, it is unlikely that elevated AC/A ratios are responsible for the high levels of myopia that occur in Hong Kong. The finding that timolol reduced AC in the stable myopes suggests that the autonomic control of accommodative convergence in these children may be different from that in emmetropic children and those with progressing myopia. 相似文献
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Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C. 相似文献
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Kenneth Micklethwaite Anna Hansen Aaron Foster Elizabeth Snape Vicki Antonenas Mary Sartor Peter Shaw Ken Bradstock David Gottlieb 《Biology of blood and marrow transplantation》2007,13(6):707-714
Cytomegalovirus reactivation and infection post-allogeneic hematopoietic stem cell transplant continue to cause morbidity and mortality. Current pharmacologic therapies are limited by side effects. Adoptive transfer of ex vivo generated cytomegalovirus-specific T cells has the potential to restore immunity, prevent cytomegalovirus, and circumvent the need for pharmacologic therapies. We have generated donor-derived cytomegalovirus-specific cytotoxic T cells using dendritic cells pulsed with the HLA-A2 restricted nonapeptide NLVPMVATV (NLV) derived from the cytomegalovirus-pp65 protein. These cytotoxic T cells have been given prophylactically to 9 recipients aged 4 to 65 years on or after day 28 post-allogeneic hematopoietic stem cell transplant. Only 2 of 9 recipients received T cell depletion in vivo or in vitro. There were no immediate adverse reactions to the infusions. During 97-798 days of follow-up, 2 recipients developed cytomegalovirus reactivation; neither developed cytomegalovirus disease or required pharmacotherapy. Three recipients developed acute graft versus host disease after infusion. Two recipients died, 1 from thrombotic thrombocytopenia purpura secondary to cyclosporine, 1 from complications of graft versus host disease. A transient increase in numbers of cytomegalovirus-specific T cells demonstrated by NLV-tetramer binding was seen in 6 recipients. Prophylactic adoptive transfer of NLV-specific T cells is safe and may be effective in preventing cytomegalovirus reactivation. 相似文献
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Human high molecular weight kininogen (HMWK), a single-chain protein with mol wt 120,000, is cleaved by human urinary kallikrein (HUK) to release kinin from within a disulfide loop and form a two-chain protein that retains all the procoagulant activity of the native molecule. Cleavage of HMWK by HUK is associated with a reduction in size to mol wt 115,000, as assessed by SDS-PAGE of unreduced protein, whereas the two chains of the reduced protein present together as a single broad band with mol wt 64,000. The 64,000 chain with procoagulant activity was chromatographically separated from the nonfunctional chain of similar size. The homogeneous procoagulant chain had an amino acid composition similar to that of smaller procoagulant ("light") chains isolated by others upon cleavage of HMWK with plasma kallikrein and elicited an antiserum that was monospecific by Ouchterlony analysis and inhibited the procoagulant function of HMWK. Thus, the limited proteolysis of HMWK by HUK has permitted, for the first time, the isolation of a stable procoagulant chain that is equal in size to the nonfunctional chain. The common terminology of "heavy" and "light" chain for kinin-free kininogen obtained with plasma kallikrein reflects the continued degradation of the procoagulant carboxyterminal chain and is not appropriate for the initial two-chain product formed when kinin is released from HMWK. It is proposed that the initial cleavage products of HMWK be designated the A-chain, the B-fragment, and the C- chain, representing the amino-terminal chain, the released vasoactive peptide containing the bradykinin sequence, and the carboxy-terminal procoagulant chain, respectively. Thus, intact HMWK would contain, in sequence, A, B, and C regions. 相似文献
6.
David Lee Shivakumar Chitturi James Kench Jacob George Steven Fuller Ken Bradstock Rita Lin Kai Ping Wong Noel Young 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):117-120
Although transjugular liver biopsies are frequently performed in patients with impaired blood coagulation, their impact on effecting changes in clinical management has not been assessed. We reviewed our experience with 43 consecutive transjugular liver biopsies performed over 3 years (1998?2000) at Westmead Hospital, Sydney, Australia. The technical success, procedural complication rates and subsequent management of these patients were ascertained from the medical case records. Forty‐two (28 men) patients were studied. The indications for liver biopsy were as follows: assessment of hepatitis/cirrhosis status (n = 21), evaluation of liver dysfunction following bone marrow transplantation (n = 19) and miscellaneous (n = 2). All liver biopsies were performed with a Cook 20‐G transjugular cutting needle device. Adequate histological samples were obtained in 42 (98%) of the 43 biopsies performed. The pre‐biopsy diagnoses were confirmed by histology in 28 cases (65%). A change in clinical diagnosis was observed in 12 (28%) patients, and there were changes to subsequent management in all 12 patients. Four patients developed procedural complications, including small neck haematomas in two patients and a self‐limiting biliary fistula in one. The only major complication was an extracapsular bleed from a hepatic laceration. This patient required emergency surgery but recovered. Transjugular liver biopsies can be effectively and safely performed in high‐risk patients with impaired coagulation. They aid accurate histological appraisal of liver dysfunction in these patients and influence clinical decision‐making. 相似文献
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The focus on quality of life issues in wound care has justly taken a far greater importance. With the acceptance that pain can be a major factor to the patient, and in particular, pain at dressing change comes the opportunity for avoidance and/or reduction strategies. Whilst pain has been associated with wound infection for millennia, it is only much more recently that this has received due attention from research and clinical practice. In this study, the nature of pain, changes in pain and pain associated with infection are the focal points. A Delphi approach, now a frequently used tool in wound care research, has been used to obtain expert opinion on these aspects of management. 相似文献
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