High-efficiency 20-50 kHz mid-infrared orientation-patterned GaAs optical parametric oscillator pumped by a 2 microm holmium laser.

We report on what are, to our knowledge, the best results obtained with an orientation-patterned GaAs optical parametric oscillator (OPO) pumped by a Q-switched 2 microm Ho:YAG laser. Up to 2.85 W are obtained for 6.1 W of pump power, corresponding to an optical-to-optical conversion efficiency of 46.5% with a threshold of 1 W. Optical damage occurred at a fluence of about 2 J/cm2. The thickness of the crystal limited the pump power. Slope efficiencies are of the same order as those obtained with ZnGeP2 OPOs pumped with the same Ho:YAG laser.

Successful treatment of severe heart failure in an infant with Hurler syndrome.

Hurler syndrome (MPS IH) is the most severe form of mucopolysaccharidosis type I. It is caused by deficiency or absence of the enzyme alpha-L-iduronidase. Cardiac involvement includes cardiomyopathy and valve and coronary pathology. Cardiomyopathy causing symptoms in an infant with MPS IH carries a very poor prognosis. We describe a previously healthy 10-week-old boy who was admitted to hospital critically ill with severe heart failure. Echocardiography on admission showed severe dilatation of the left ventricle and moderate insufficiency of the left-sided cardiac valves. Accumulation of heparan sulfate and dermatan sulfate substrates in the urine and leukocyte analysis confirmed the diagnosis of MPS IH. Enzyme replacement therapy (ERT) with intravenous laronidase at a standard dosage of 100 U/kg weekly was started soon after. This improved the child's general clinical wellbeing dramatically. His cardiac function improved steadily over a period of months. Stem cell transplantation from cord blood is not available in Norway and he underwent successful transplantation from an unrelated bone marrow donor at the age of 11 months. ERT was stopped four months later. At the age of 26 months his heart function is close to normal and he is currently on no medication. This report highlights three important clinical issues: (1) MPS IH must be considered in infants with cardiomyopathy; (2) early ERT may have a significant impact on short-term outcome in children less than 18 months old with severe cardiomyopathy; (3) our report confirms that patients in poor condition benefit from ERT before stem cell transplantation.

A novel model of fibroblast-mediated cartilage destruction.

In rheumatoid arthritis (RA), fibroblasts have been shown to be crucial for disease progression as well as joint destruction. In the model of human/murine SCID arthritis, synovial explants as well as fibroblasts from human rheumatoid synovial membrane induce destructive arthritis in immunodeficient mice. Hereby, the underlying cartilage destruction is accomplished by murine fibroblasts. Therefore, murine destructive fibroblasts represent a promising tool to investigate destruction of articular cartilage and bone. In this context, a novel destructive murine fibroblast line (LS48) was examined for morphological, ultrastructural, immunological and functional cellular parameters. These cells were injected into knees of SCID mice. Subsequently, the animals were monitored for joint swelling and serological parameters of arthritis by radiological methods. Finally, cartilage destruction was assessed morphologically. Cultured LS48 cells exhibit characteristic features that resemble those of activated synovial fibroblasts in human RA. Expression levels of inducible nitric oxide synthase, interleukin-6, tumour necrosis factor-alpha and matrix metalloproteinases were comparable to those detected in invasive human fibroblasts. The instillation of 5 x 10(5) LS48 cells into the knee joints of SCID mice initiated a rapid progressive process, that caused cartilage destruction within 10 days, and morphological examinations revealed that articular cartilage was infiltrated by the fibroblasts injected previously. In summary, the intra-articular application of LS48 cells represents a rapid and highly reproducible model to investigate the initiation and progression of cartilage destruction in connection with RA therapy and represents an easy-to-handle animal model.

Ho:YAG laser intracavity pumped by a diode-pumped Tm:YLF laser.

We report a compact Ho:YAG laser that is intracavity pumped by a diode-pumped Tm:YLF laser. Both lasers exhibit pulse mode behavior. Operating both crystals at room temperature (25 degrees C), we obtained 1.6 W of average output at 2.09 microm from the Ho:YAG laser for 15.4 W of diode power incident upon the Tm:YLF rod and a slope efficiency of 21%.

Angiogenic and angiostatic factors in the molecular control of angiogenesis.

The vascular system that ensures an adequate blood flow is required to provide the cells with sufficient supply of nutrients and oxygen. Two different mechanisms of the formation of new vessels can be distinguished: vasculogenesis, the formation of the first primitive vascular plexus de novo and angiogenesis, the formation of new vessels from preexisting ones. Both processes are regulated by a delicate balance of pro- and anti-angiogenic factors. Physiologically, angiostatic mediators outweigh the angiogenic molecules and angiogenesis does not occur. Under certain conditions such as tumor formation or wound healing, the positive regulators of angiogenesis predominate and the endothelium becomes activated. Angiogenesis is initiated by vasodilatation and an increased permeability. After destabilization of the vessel wall, endothelial cells proliferate, migrate and form a tube, which is finally stabilized by pericytes and smooth muscle cells. Numerous soluble growth factors and inhibitors, cytokines and proteases as well as extracellular matrix proteins and adhesion molecules strictly control this multi-step process. The properties and interactions of angiogenic molecules such as VEGFs, FGFs, angiopoietins, PDGF, angiogenin, angiotropin, HGF, CXC chemokines with ELR motif, PECAM-1, integrins and VE-cadherin as well as angiostatic key players such as angiostatin, endostatin, thrombospondin, CXC chemokines without ELR motif, PEDF are discussed in this review with respect to their molecular impact on angiogenesis.

Isolation and characterization of rheumatoid arthritis synovial fibroblasts from primary culture--primary culture cells markedly differ from fourth-passage cells.

To reduce culture artifacts by conventional repeated passaging and long-term culture in vitro, the isolation of synovial fibroblasts (SFB) was attempted from rheumatoid arthritis (RA) synovial membranes by trypsin/collagenase digest, short-term in vitro adherence (7 days), and negative isolation using magnetobead-coupled anti-CD14 monoclonal antibodies. This method yielded highly enriched SFB (85% prolyl-4-hydroxylase+/74% Thy-1/CD90+ cells; <2% contaminating macrophages; <1% leukocytes/endothelial cells) that, in comparison with conventional fourth-passage RA-SFB, showed a markedly different phenotype and significantly lower proliferation rates upon stimulation with platelet-derived growth factor and IL-1beta. This isolation method is simple and reliable, and may yield cells with features closer to the in vivo configuration of RA-SFB by avoiding extended in vitro culture.

Group support for couples coping with a cardiac condition.

BACKGROUND/RATIONALE: Support groups of peers were designed to convey support specific to stressful situations encountered by persons with a first-time myocardial infarction and by their spouse or partners. There were no previous published support intervention studies focused on the couple. Survivors and spouses (n=28) participated in a pilot study which tested the effect of a 12-week support group intervention. DESIGN: The support groups for couples were cofacilitated by a peer and professional. The facilitators recorded field notes, while participants completed weekly diaries about the intervention activities. Following the intervention, participants were interviewed individually and facilitators were interviewed jointly about the perceived effect of the intervention and influencing factors. This article focuses on the facilitators' and participants' perceptions of intervention processes and outcomes. FINDINGS: Support processes in the group included social comparison, social learning, and social exchange. Three types of support--emotional, information, and affirmation--were provided. All participants were satisfied with the support intervention and referred to the positive effect on their coping, confidence, outlook, and spousal relationship. Factors that influenced the intervention effect were participant input, cofacilitation, similarity of group members, and the provision of information and support. CONCLUSIONS: Future interventions could consider similarity of peers, leadership, and optimum timing and duration.

Myocardial infarction: survivors' and spouses' stress, coping, and support.

Despite evidence that spouses play an important role in the recovery of MI survivors, there have been few studies of pertinent psychosocial factors from the perspectives of both survivors and spouses. Accordingly, the aim of this study was to describe stress, coping strategies and social support experienced by survivors and spouses. This study was limited to first-time MI to focus on a time of uncertainty and transition. Twenty-eight persons (14 couples) participated. Both survivors and their spouses reported similar post-MI stresses: emotional impact, lifestyle changes, encounters with health professionals, and their partners' reactions. Spouses and survivors used diverse strategies to cope with the stresses of MI. Seeking informational support was prevalent. Both spouses and survivors engaged in 'protective buffering' of their partners. Couples described deficient support, conflict and miscarried helping efforts within their relationships. Spouses and survivors referred to inadequate informational support from health professionals.

Efficient pulsed 946-nm laser emission from Nd:YAG pumped by a titanium-doped sapphire laser.

Efficient pulsed room-temperature laser emission at 946 nm is obtained from a Nd:YAG rod pumped by a Ti-doped sapphire laser in the free-running mode. Three bonded YAG rods of 3-mm diameter with different Nd concentrations and active lengths were tested. A maximum output energy of 83.5 mJ at 3 Hz was obtained with a slope efficiency of 32.3% in an end-pumping configuration.

Stress, coping, and social support as psychosocial factors in readmissions for ischaemic heart disease.

This exploratory investigation aimed to identify psychological and social factors associated with early (4 months postdischarge) readmission to hospital of persons with ischaemic heart disease (IHD). Data on stress (Stress Appraisal Scale), coping strategies (Ways of Coping Questionnaire), and social network/social support (Norbeck Social Support Questionnaire) were collected from 100 persons with the primary diagnosis of IHD prior to discharge from hospital. Twenty-four persons were readmitted during the 4-month study period. The sample was divided into two groups for analysis: (1) persons with a first admission for IHD, and (2) persons with a prior history of admission for IHD. In comparison to persons with multiple admissions for cardiac illness, first time admissions appraised their IHD as less central and threatening, perceived less affective and affirmational support from health professionals, and identified health professionals less and neighbours more as sources of support. Greater use of the coping strategy 'seeking social support' was associated with the readmission of persons who had had their first admission for IHD. Less use of the coping strategy 'accepting responsibility' was associated with the readmission of persons who had a history of prior admission for IHD.

Insights from a nursing research program on social support.

This paper highlights the conceptual and practical implications of a nursing research program that focuses on social support. The diverse dimensions of the construct of social support; its relationship to stress and coping; and its impact on health, health behaviour, and use of health services are explicated in the conceptual framework underpinning the program. These associations will be elucidated by citing examples from eight assessment studies and four intervention studies. The research program yielded new insights and reinforced reported findings of other social-support research.

Social support in children with a chronic condition.

This study used a descriptive exploratory design to describe social support in children with a chronic condition and how children use social support in coping with everyday demands and demands related to their condition. Participants comprised 62 school-aged children (16 with diabetes, 16 with cystic fibrosis, 15 with spina bifida, and 15 with no chronic illness). Data were collected about their social-support networks, the support functions provided by the networks, and their satisfaction with support. The children also described the social support they received and their use of social support as a coping strategy in specific stressful situations. The healthy children had the largest support networks overall and the largest peer networks. Children with spina bifida had the smallest networks overall and the smallest number of peers in their networks. Healthy children reported more support overall than the children in the illness groups. Both the healthy children and the children with a chronic condition described academic issues as the main source of everyday stress. Children with a chronic condition identified restriction due to illness as the key illness-related stressor. Children with a chronic condition reported more stress and more support-seeking in everyday stressful situations than in illness situations. The results will guide the design of a future social-support intervention for children with a chronic condition.

[Accidental atropine poisoning. Anticholinergic syndrome in a child after intranasal overdose]. / Aksidentell atropinforgiftning. Antikolinergt syndrom hjå eit barn med overdosering nasalt.

As paediatricians we are often reminded of the importance of correct marking and storage of drugs to prevent accidental intoxication. We report on a patient who developed typical signs of central and peripheral anticholinergic syndrome within a few hours after intake of atropine through her nose. Clinical presentation and treatment are described. Children with fever, Down's syndrome or convulsive disorders seem to be particularly sensitive to atropine.

Characterization of KNbO(3) crystal for frequency doubling of a tunable pulsed near-infrared laser.

Using KNbO(3) crystals for second-harmonic generation in the blue spectral range, we have obtained conversion efficiencies as high as 53.7%. To our knowledge this value is the highest reported for a pulsed laser. A gainswitched nanosecond Ti:sapphire oscillator, amplified by a Cr:LiSrAlF(6) multipass amplifier, was used as the fundamental light source. The maximum energy obtained at the harmonic wavelength of 430 nm was 38 mJ for a bandwidth of 230 MHz.

Use of an absorbent in laser lithotripsy with dye lasers: in vitro study of fragmentation efficiency and jet formation.

Among other things, the fragmentation efficiency of laser lithotripsy using a dye laser depends upon the physical properties of the surface of the calculus, especially optical absorption. In this in vitro study we were able to increase the fragmentation efficiency on white, nonabsorbing calculi by introducing an absorbing liquid between the distal end of the fiber and the stone surface. This absorbing liquid (in our case potassium dichromate) provides a reliable plasma ignition and thus makes the fragmentation independent of the properties of the stone surface. Furthermore, we examined and documented the existence of liquid jets that were produced by the collapse of a cavitation bubble near a stone. We observed considerable fragmentation effects on artificial stones that were, however, inferior to those achieved with the fiber in contact with the stone. This work suggests that the effects of a liquid jet should be taken into consideration when using a holmium:YAG laser for lithotripsy.

Mice transgenic for the human carcinoembryonic antigen gene maintain its spatiotemporal expression pattern.

The tumor marker carcinoembryonic antigen (CEA) is predominantly expressed in epithelial cells along the gastrointestinal tract and in a variety of adenocarcinomas. As a basis for investigating its in vivo regulation and for establishing an animal model for tumor immunotherapy, transgenic mice were generated with a 33-kilobase cosmid clone insert containing the complete human CEA gene and flanking sequences. CEA was found in the tongue, esophagus, stomach, small intestine, cecum, colon, and trachea and at low levels in the lung, testis, and uterus of adult mice of independent transgenic strains. CEA was first detected at day 10.5 of embryonic development (embryonic day 10.5) in primary trophoblast giant cells and was found in the developing gut, urethra, trachea, lung, and nucleus pulposus of the vertebral column from embryonic day 14.5 onwards. From embryonic day 16.5 CEA was also visible in the nasal mucosa and tongue. Because this spatiotemporal expression pattern correlates well with that known for humans, it follows that the transferred genomic region contains all of the regulatory elements required for the correct expression of CEA. Furthermore, although mice apparently lack an endogenous CEA gene, the entire repertoire of transcription factors necessary for correct expression of the CEA transgene is conserved between mice and humans. After tumor induction, these immunocompetent mice will serve as a model for optimizing various forms of immunotherapy, using CEA as a target antigen.

Hope and social support as coping resources for adults waiting for cardiac transplantation.

Previous research has indicated that interpersonal support and hopefulness are important for people waiting for cardiac transplantation. However, little is known about their supportive networks, or whether support and hope are factors that enable coping during the waiting period. This study described the social networks of cardiac transplant candidates, and explored whether social support and hope contributed to effective coping. Thirty-one individuals in four Canadian transplant centres completed questionnaires regarding social support (Norbeck Social Support Questionnaire), hope (Miller Hope Scale), and coping (Jalowiec Coping Scale). Telephone interviews provided supplementary data about perceptions of helpful support behaviours. Study findings suggest that hope was the only variable that contributed to coping effectiveness (R2 = .41) and that respondents' social networks (primarily family, friends, and health professionals) were important sources of support. The data provide insight into the behaviours that transplant candidates find supportive and suggest strategies to maintain hopefulness during the waiting period.

Development of a quality assurance tool for critical care.

Current conditions in the health care arena demand that nurses be held accountable for the quality of nursing care delivered. Nursing administrators today face multiple challenges which include incorporating the expanding role of the nurse, dealing with financial constraints, and meeting the demands of an increasingly informed public. These factors combine to emphasize the need to examine the quality of care delivered and to identify and promote effective nursing care behaviours. The use of a quality assurance tool can be invaluable in revealing areas of both excellence and weakness in the care of clients, as well as providing a solid foundation for change. This paper will follow the authors through the development and implementation of a unit-specific quality assurance tool for a critical care area. We begin with a brief review of the literature and explore the factors relevant to our decision to choose a concurrent chart audit as our tool. We then describe the discovery of standards, the design of the tool itself, and follow the process of testing, approval and implementation of the tool for use in our institution. Finally, we explain the methods used to introduce the tool to staff and elicit their support to monitor and thus improve the quality of nursing care delivered.