Biomedical subjects

C Springer

Publications and source records attributed to C Springer.

At least 19 recordsLinked to original sources

PubMed2006

[Static fundus perimetry in normals. Microperimeter 1 versus SLO].

BACKGROUND: The Microperimeter 1 (MP-1) allows for fundus-controlled static perimetry of the central visual field. The purpose of this study was to compare MP-1 fundus perimetry with the already established scanning laser ophthalmoscope (SLO) fundus perimetry concerning detected threshold values of light increment sensitivity in normals. METHOD: In 31 eyes of 31 healthy volunteers a fundus controlled static threshold perimetry was carried out each with the MP-1 (Nidek Technologies) and the SLO (Rodenstock). In the central 21 degrees x 12 degrees visual field light increment sensitivity threshold values for 40 corresponding stimulus locations were compared in a rectangular 3 degree-grid. RESULTS: The average light increment sensitivity was 19.1+/-0.5 dB with the MP-1 and 17.2+/-0.9 dB with the SLO. On average the threshold values of the 40 corresponding test locations were 1.9+/-1.3 dB higher with the MP-1 than with the SLO. CONCLUSION: Both the MP-1 and SLO offer the possibility of a reproducible functional analysis of the central retina under simultaneous fundus control. For comparison of results of the MP-1 and SLO fundus perimetry, a correction factor of approximately 2 dB should be used.

Adult↗

PubMed2006

[Central serous chorioretinopathy--retinal function and morphology: microperimetry and optical coherence tomography].

BACKGROUND: The purpose of this study was to evaluate and compare retinal function and morphology in patients with central serous chorioretinopathy (CSC) using fundus perimetry and optical coherence tomography (OCT). PATIENTS AND METHODS: In 14 eyes of 14 patients with unilateral and first manifestation of CSC, fundus perimetry with the Microperimeter 1 (MP1) as well as OCT were carried out. The average retinal thickness and the average differential light threshold of the corresponding visual field were analyzed. RESULTS: All patients presented a serous detachment of the central neurosensory retina with a maximal retinal thickness of 381+/-82 microm. The microperimetric examination revealed on average a mean defect of 8.3+/-3.8 dB, which showed a good correlation to retinal thickness (r=0.73). Likewise, maximal retinal thickness and mean threshold values in the corresponding visual field displayed a good correlation (r=-0.58). CONCLUSION: The MP1 enables quantification of functional defects in patients with CSC. Although visual acuity was only slightly reduced, all patients showed extensive scotomata in fundus perimetry, which correlated well with retinal thickness.

Adult↗

PubMed2005

Exhaled nitric oxide in the diagnosis of asthma: comparison with bronchial provocation tests.

BACKGROUND: Bronchial provocation tests such as exercise, methacholine (MCH), and adenosine-5'-monophosphate (AMP) challenges are used extensively in the diagnosis of asthma. A study was undertaken to determine whether exhaled nitric oxide (eNO) can be used to diagnose asthma in patients with non-specific respiratory symptoms and to compare this test with conventional provocation tests. METHODS: Patients with non-specific respiratory symptoms and normal spirometric parameters were included in the study. eNO was measured and exercise, MCH and AMP challenges performed in all subjects. Patients were defined as asthmatic based on clinical follow up 24 months after testing. RESULTS: Forty patients were considered asthmatic and 45 were not. The area under receiver operating characteristic curves gave values of 0.896 for eNO, 0.781 for exercise, 0.924 for MCH, and 0.939 for AMP (p = 0.033, 0.575 and 0.085 for eNO v exercise, MCH and AMP respectively). From our data, a cut off value of NO > 7 ppb at a flow rate of 250 ml/s best differentiates between asthmatics and non-asthmatics (sensitivity 82.5%, specificity 88.9%). Optimal cut off values for other tests were exercise: deltaFEV1 > or = 10% (sensitivity 57.9%, specificity 100%); PC20-MCH: < or = 3 mg/ml (sensitivity 87.5%, specificity 86.7%); and PC20-AMP: < or = 150 mg/ml (sensitivity 89.5%, specificity 95.6%). CONCLUSIONS: Measurement of eNO can be used as a safe, simple and rapid test for the diagnosis of asthma and is as good as bronchial provocation tests.

Adenosine Monophosphate↗

PubMed2004

Adult alpha-mannosidosis: clinical progression in the absence of demyelination.

Alpha-mannosidosis is an inherited lysosomal storage disease. The authors report three siblings (ages 38 to 47 years) with the rare adult variant. All three had late-onset ataxia and retinal degeneration, adding to hearing loss, cognitive impairment, and dysotosis multiplex. One sibling also had psychosis. MRI revealed cerebellar atrophy and predominantly parieto-occipital white matter changes. MR spectroscopy showed no evidence for demyelination. It appears that the disabling course of adult alpha-mannosidosis is caused by lysosomal accumulation rather than demyelination.

Adult↗

PubMed2004

[Deep sclerectomy using a hyaluronate implant versus trabeculectomy. A comparison of two glaucoma operations using mitomycin C].

BACKGROUND: It was investigated whether a very low target pressure could be achieved by modification of deep sclerectomy without losing the advantages of non penetrating surgery in comparison to conventional filtration surgery. PATIENTS AND METHODS: A total of 22 eyes from 22 patients with advanced open angle glaucoma were randomly assigned to receive a deep sclerectomy or a trabeculectomy. Both groups received 0.02% mitomycin C under the conjunctiva prior to preparation of the scleral flap. In the deep sclerectomy group at least parts of the outer trabecular meshwork were removed until an apparent filtration was achieved. A dry cross-linked hyaluronate served as an implant. In the other group a classical trabeculectomy was performed. RESULTS: The median intraocular pressure 12 months post-operation was 11.5 mm Hg in the deep sclerectomy group compared to 11 mm Hg in the trabeculectomy group; the median of the relative IOP reduction was -47% in the deep sclerectomy group, and -57% in the trabeculectomy group. The best corrected visual acuity was unchanged 12 months postoperatively in both groups. DISCUSSION: As a more aggressive IOP-lowering procedure (intended filtration, use of antimetabolites) deep sclerectomy proved to be as effective as trabeculectomy. Nevertheless, the advantages of the more difficult surgical procedure concerning visual acuity, complications and surgical interventions were lost postoperatively.

Adult↗

PubMed2003

What is the role of tests of lung function in the management of infants with lung disease?

This review considers whether there is a role for lung function tests in the clinical management of infants with lung disease. The purpose of testing lung function in older subjects, the tests available for infants, and the practical problems of testing lung function in infants are considered. After reviewing all the facts, we suggest that there are four situations in which lung function testing should be recommended for infants, as follows: (1) the infant who presents with unexplained tachypnea, hypoxia, cough, or respiratory distress in whom a definitive diagnosis is not apparent from physical examination and other, less difficult investigations; (2) the infant with severe, continuous, chronic obstructive lung disease who does not respond to an adequate clinical trial of combined corticosteroid and bronchodilator therapy; (3) the infant with known respiratory disease of uncertain severity in whom there is need to justify management decisions; and (4) research and development. A review of 62 recent publications to determine how lung function tests are being used at the present time showed that they are being used overwhelmingly for research. The role of lung function testing in the clinical management of infants has not been established, and research is needed to clarify this situation. We suggest that such studies should explore the role of lung function tests in infants with specific symptoms, signs, or diagnoses, taking into account information from other types of investigation and the cost/benefit/risk ratios.

Child, Preschool↗

PubMed2002

A phase I trial of antibody directed enzyme prodrug therapy (ADEPT) in patients with advanced colorectal carcinoma or other CEA producing tumours.

Antibody-directed enzyme prodrug therapy is a targeted therapy in which a prodrug is activated selectively at the tumour site by an enzyme, which has been targeted to the tumour by an antibody (antibody-enzyme conjugate). Previous clinical trials have shown evidence of tumour response, however, the activated drug had a long half-life, which resulted in dose-limiting myelosuppression. Also, the targeting system, although giving high tumour to blood ratios of antibody-enzyme conjugate (10 000 : 1) required administration of a clearing antibody in addition to the antibody-enzyme conjugate. The purpose of this current study therefore was to attempt tumour targeting of the antibody-enzyme conjugate without the clearing antibody, and to investigate a new prodrug (bis-iodo phenol mustard, ZD2767P) whose activated form is highly potent and has a short half-life. Twenty-seven patients were treated with antibody-directed enzyme prodrug therapy using A5CP antibody-enzyme conjugate and ZD2767P prodrug, in a dose-escalating phase I trial. The maximum tolerated dose of ZD2767P was reached at 15.5 mg m(-2)x three administrations with a serum carboxypeptidase G2 level of 0.05 U ml(-1). Myelosuppression limited dose escalation. Other toxicities were mild. Patients' quality of life was not adversely affected during the trial as assessed by the measures used. There were no clinical or radiological responses seen in the study, but three patients had stable disease at day 56. Human anti-mouse antibody and human anti-carboxypeptidase G2 antibody were produced in response to the antibody enzyme conjugate (A5CP). The antibody-enzyme conjugate localisation data (carboxypeptidase G2 enzyme levels by HPLC on tumour and normal tissue samples, and gamma camera analysis of I-131 radiolabelled conjugate) are consistent with inadequate tumour localisation (median tumour: normal tissue ratios of antibody-enzyme conjugate of less than 1). A clearance system is therefore desirable with this antibody-enzyme conjugate or a more efficient targeting system is required. ZD2767P was shown to clear rapidly from the circulation and activated drug was not measurable in the blood. ZD2767P has potential for use in future antibody-directed enzyme prodrug therapy systems.

Adult↗

PubMed2002

Early diagnosis of primary ciliary dyskinesia in a newborn without situs inversus.

UNLABELLED: Primary ciliary dyskinesia has been reported as a rare cause of respiratory distress during the neonatal period. This diagnosis is readily suspected in cases presenting with accompanying situs inversus. The aim of this study was to report on a pair of siblings with primary ciliary dyskinesia. The first case was an infant diagnosed with primary ciliary dyskinesia at the age of 14 d despite lack of situs inversus. The infant had presented with respiratory distress and atelectasis almost immediately after birth. The sibling, born one year later, presented with situs inversus, therefore allowing diagnosis of primary ciliary dyskinesia to be made immediately after birth. CONCLUSIONS: Diagnosis of primary ciliary dyskinesia should be considered in newborns presenting with respiratory distress or atelectasis. Early institution of an adequate treatment programme and follow-up may reduce or prevent further complications of the disease.

Biopsy, Needle↗

PubMed2001

Exhaled nitric oxide and asthma in young children.

Exhaled nitric oxide (eNO) has been used to diagnose asthma in adults and children using either the slow vital capacity method (SVCm) or, in younger children, the tidal breathing method (TBm). Adenosine 5'-monophosphate (AMP) challenge also has been found to be a sensitive and specific test for the diagnosis of asthma. In the present study, we used the AMP provocation concentration that caused wheezing (PCW) to confirm the diagnosis of asthma (PCW < or = 200 mg/mL). We studied 36 children (2-7 years) with mild intermittent asthma, 13 children (3-7 years) with moderate persistent asthma treated with inhaled steroids, 20 nonasthmatic children (2-7 years) with chronic cough and recurrent pneumonia, and 15 healthy children (4-6 years). Expired gas was collected in collection bags by the TBm, and eNO was measured. We evaluated the efficacy of eNO values in diagnosing asthma. The mean eNO level of the mild intermittent asthmatic children (5.6 +/- 0.4 ppb) not receiving inhaled corticosteroids was significantly higher (ANOVA P < 0.0001) than that of the moderate persistent asthmatics who were treated with inhaled steroids, the nonasthmatic children with chronic cough, and the group of healthy children (3.7 +/- 0.6 ppb, P < 0.05; 3.2 +/- 0.3 ppb, P < 0.001; 2.2 +/- 0.2 ppb, P < 0.001, respectively). The points of intersection for sensitivity and specificity curves of eNO to differentiate mild intermittent asthmatics from nonasthmatic children with chronic cough and from healthy children were 77% and 88% for eNO values of 3.8 ppb and 2.9 ppb, respectively. We conclude that eNO collected by the TBm can differentiate steroid-naive young children with intermittent asthma from healthy children, from nonasthmatic children with chronic cough, and from asthmatic children treated with inhaled steroids.

Analysis of Variance↗

PubMed2001

Can peak expiratory flow measurements estimate small airway function in asthmatic children?

BACKGROUND: Asthma is characterized in part by small airways dysfunction. Peak expiratory flow (PEF) measurement has been suggested by all international guidelines as an important tool in asthma management. The correlation between PEF and FEV(1) but not with forced expired flow at 50% of vital capacity (FEF(50)) is well-established. STUDY OBJECTIVE: To determine the value of PEF measurement as a predictor of small airways status as expressed by FEF(50). DESIGN: Analysis of the association between PEF and FEF(50) in single and multiple determinations. PATIENTS: One hundred eleven asthmatic children (mean age, 11.8 years), grouped in the following way according to FEV(1) values: within normal range (n = 46); mildly reduced FEV(1) (n = 44); and moderately/severely reduced FEV(1) (n = 21). RESULTS: Overall, FEF(50) and PEF were significantly correlated (r = 0.49; p < 0.0001). However, in 41.6% of the patients, the actual FEF(50) differed by > 20% from the calculated FEF(50). PEF has a high specificity (82.4%) but a poor sensitivity (51.7%) to detect FEF(50) status. PEF was better able to reflect abnormal FEF(50) in the patients with more severe asthma and to reflect normal FEF(50) values in the healthier patients. In patients with multiple measurements (n = 40), the correlation between FEF(50) and PEF was significantly better than that derived from a single determination (multiple measurements r = 0.77; single measurement, r = 0.49). CONCLUSIONS: Although PEF is an important tool in the management of asthmatic patients, it does not yield a complete picture because it is not sensitive in detecting small airways function. It is best used at home along with regular spirometry measurements at the clinic. PEF may serve as a better index of changes in small airways function once an individual regression is determined.

Adolescent↗

PubMed2000

Exercise, methacholine, and adenosine 5'-monophosphate challenges in children with asthma: relation to severity of the disease.

Bronchial hyperreactivity is a characteristic feature of asthma and can be evaluated by different challenges. The aim of this study was to compare exercise, methacholine (MCH), and adenosine 5'-monophosphate (AMP) challenges in 135 children and young adults (mean age +/- SD, 12.4+/-3.9 years) with asthma, and to examine the utility of the different challenges in predicting those children with asthma likely to require prophylactic antiinflammatory treatment. The sensitivity of MCH challenge in detecting bronchial hyperreactivity (at or below 8 mg/mL) was 98%, that of AMP challenge (at or below 200 mg/mL) 95.5%, and that of exercise (more than 8.2% fall in FEV(1)) was 65%. There was a significant difference between mild asthmatic children (85 patients, intermittent asthma, step 1 of NIH guidelines) and moderate asthmatics (50 patients, steps 2 and 3 of guidelines) in relation to the logarithmic mean provocation concentration to elicit a 20% fall in FEV(1) (PC(20)) to MCH (0.49 mg/mL vs. 0.15 mg/mL, P<0.00001), that to AMP (7.67 mg/mL vs. 3.60 mg/mL, P = 0.001), and in relation to the mean percent fall in FEV(1) after exercise (13.9% vs. 22.0%, P = 0.001). Sensitivity and specificity curves between the two severity groups of asthma were constructed, and the intersection point of the two curves for each type of challenge was determined. When mild asthmatics were compared to moderate asthmatics, the intersection points for MCH, AMP, and exercise were 66%, 63%, and 61%, respectively. Logistic regression analysis and receiver operating characteristic (ROC) curves of the three challenges for the two severity groups of asthma showed that methacholine was a better discriminating challenge between the severity groups than the other two challenges. We conclude that the sensitivities of AMP and MCH challenges in the detection of bronchial hyperreactivity in children and young adults with asthma are very similar and higher than that of exercise. There is a significant difference between mild and moderate asthmatics within the three bronchial challenges, with MCH discriminating better than AMP or exercise between groups.

Adenosine Monophosphate↗

PubMed2000

Gender differences in young adolescents' exposure to violence and rates of PTSD symptomatology.

Gender differences in exposure to violence and levels of PTSD symptomatology were examined in a school-based sample of 621 young adolescents. Also investigated as predictors of PTSD symptoms were cognitive coping strategies, perceived social support, and the affective experience of fear. Results support the importance of evaluating gender differences, differentiating between violence by type and location, and considering both cognitive and affective factors as predictors of PTSD symptomatology.

Adaptation, Psychological↗

PubMed2000

Housing status and health care service utilization among low-income persons with HIV/AIDS.

OBJECTIVE: To examine the impact of housing status on health service utilization patterns in low-income HIV-infected adults. DESIGN: A survey of 1,445 HIV-infected Medicaid recipients in New York State between April 1996 and March 1997. MAIN RESULTS: Six percent of study participants were homeless, 24.5% were "doubled-up," and 69.5% were stably housed. Compared with the stably housed, doubled-up and homeless participants were less likely to be seeing a physician regularly (P = .0001), and if seeing a physician, they were likely to have been doing so for a significantly shorter time (P = .02). The homeless were also less likely than either stably housed or doubled-up individuals to see the same physician or group of physicians at each ambulatory visit (P = .007). In addition, a higher proportion of the homeless had made one or more hospital visits over the prior 3 months than the nonhomeless. After multivariate adjustment, doubled-up participants were found to make more emergency room visits, the homeless were less likely to be taking prophylaxis for Pneumocystis carinii pneumonia, and both the doubled-up and the homeless were shown to use slightly more outpatient care than the stably housed. CONCLUSION: Our study documents differences in health care utilization patterns across stably housed, doubled-up, and homeless HIV-infected persons after controlling for health insurance coverage. These differences, especially those pertaining to outpatient services, suggest that the unstably housed may be receiving less adequate health care than the stably housed, and hence may be more likely to experience adverse clinical outcomes.

Adult↗

PubMed2000

Pulmonary haemorrhagic syndromes in children.

Pulmonary haemorrhage in children is rare and may be either focal or diffuse, idiopathic or associated with an underlying disease. Focal bleeding is usually associated with congenital anomalies or localized acquired disease. Many of the disorders causing diffuse alveolar haemorrhage appear to be immunologically mediated. Treatment modalities include management of the underlying disease and the use of corticosteroids, chloroquine and/or cytotoxic drugs and induce remission in more than half of the patients with diffuse haemorrhage.

Child↗

PubMed2000

Efficacy and safety of methacholine bronchial challenge performed by auscultation in young asthmatic children.

The measurement of bronchial reactivity is an important aid in the diagnosis of asthma, but the technique using spirometry is not feasible in young children. The aim of the present study was to determine the efficacy and safety of a modification of the chest auscultation method in the assessment of bronchial reactivity to inhaled methacholine in young asthmatic children. One hundred forty-six young children with asthma (mean age, 4.3 yr) underwent bronchial challenges with nebulized methacholine using the auscultation method (PCW). The end point was defined as the appearance of wheezing, oxygen desaturation, or tachypnea. For comparison, 30 children and young adults with asthma underwent bronchial provocation with methacholine using spirometry (PC(20)). A positive response using the auscultation method was observed in 95.9% of the younger children, and wheezes alone or in combination with other signs appeared in 80.8% of them. The mean desaturation at the end point was 4.6% (PCW) and 5.0% (PC(20)), with a similar pattern in the two groups. Cough was not helpful in determining the end point. We conclude that the modified auscultation method is effective and safe, with wheeze appearing at the end point in the large majority of the children.

Adolescent↗

PubMed2000

Chalcone, acyl hydrazide, and related amides kill cultured Trypanosoma brucei brucei.

BACKGROUND: Protozoan parasites of the genus Trypanosoma cause disease in a wide range of mammalian hosts. Trypanosoma brucei brucei, transmitted by tsetse fly to cattle, causes a disease (Nagana) of great economic importance in parts of Africa. T. b. brucei also serves as a model for related Trypanosoma species, which cause human sleeping sickness. MATERIALS AND METHODS: Chalcone and acyl hydrazide derivatives are known to retard the growth of Plasmodium falciparum in vitro and inhibit the malarial cysteine proteinase, falcipain. We tested the effects of these compounds on the growth of bloodstream forms of T. b. brucei in cell culture and in a murine trypanosomiasis model, and investigated their ability to inhibit trypanopain-Tb, the major cysteine proteinase of T. b. brucei. RESULTS: Several related chalcones, acyl hydrazides, and amides killed cultured bloodstream forms of T. b. brucei, with the most effective compound reducing parasite numbers by 50% relative to control populations at a concentration of 240 nM. The most effective inhibitors protected mice from an otherwise lethal T. b. brucei infection in an in vivo model of acute parasite infection. Many of the compounds also inhibited trypanopain-Tb, with the most effective inhibitor having a Ki value of 27 nM. Ki values for trypanopain-Tb inhibition were up to 50- to 100-fold lower than for inhibition of mammalian cathepsin L, suggesting the possibility of selective inhibition of the parasite enzyme. CONCLUSIONS: Chalcones, acyl hydrazides, and amides show promise as antitrypanosomal chemotherapeutic agents, with trypanopain-Tb possibly being one of their in vivo targets.

Amides↗

PubMed1999

Cut-off points defining normal and asthmatic bronchial reactivity to exercise and inhalation challenges in children and young adults.

An analysis was undertaken to determine the optimal cut-off separating an asthmatic from a normal response to a bronchial provocation challenge by exercise and the inhalation of methacholine or histamine in children and young adults. Data were extracted, after appropriate correction, from published studies available in Medline of large random populations that complied with preset criteria of suitability for analysis, and the distribution of bronchial reactivity in the healthy population for exercise and inhalation challenges were derived. Studies on the response to exercise and methacholine inhalation in 232 young asthmatics of varying severity were carried out by the authors and the distribution of bronchial reactivity of a young asthmatic population obtained. Comparisons of the sensitivity and specificity of the challenges were aided by the construction of receiver operating characteristic curves. The optimal cut-off point of the fall in forced expiratory volume in one second (FEV1) after exercise was 13%, with a sensitivity (power) of 63% and specificity of 94%. For inhalation challenges, the optimal cut-off point for the dose of methacholine or histamine causing a 20% fall in FEV1 was 6.6 micromol, with a sensitivity of 92% and a specificity of 89%. The cut-off values were not materially affected by the severity of the asthma and provide objective data with which to evaluate the results of bronchial provocation challenges in children and young adults.

Administration, Inhalation↗

PubMed1999

Clinical and genetic risk factors for cystic fibrosis-related liver disease.

OBJECTIVE: The aim of this study was to define the role of possible risk factors for the development of cystic fibrosis (CF)-related liver disease and to analyze the association between liver disease and the different genotypes present in the Israeli CF patient population. PATIENTS AND METHODS: All patients followed at the seven CF centers in Israel were included in this study. Liver disease was determined by persistently elevated serum liver enzymes and/or bilirubin, and/or significant ultrasonographic changes suggestive of chronic liver disease. The following clinical parameters were evaluated: ethnic origin, age at assessment of liver function, sex, history of meconium ileus, pancreatic function, history of distal intestinal obstruction syndrome, pulmonary function, and cystic fibrosis transmembrane conductance regulator mutation analysis. RESULTS: Of the 288 patients screened, 80 (28%) had liver disease. Of the 256 patients with pancreatic insufficiency, 80 (31%) had liver disease compared with none of the 32 patients with pancreatic sufficiency. Genotype-phenotype correlation was performed on 207 patients carrying identified mutations that were previously classified according to phenotype severity. Liver disease was found in 56 (32%) of 173 patients carrying mutations associated with a severe phenotype and in 6 (38%) of 16 patients carrying at least one mutation associated with a variable genotype (G85E and/or 5T allele). None of the 18 patients carrying the 3849+10kb C->T mutation had liver disease. Prevalence of liver disease increased with age. No correlation was found between liver disease and severity of lung disease, nutritional status, history of meconium ileus, or distal intestinal obstruction syndrome. CONCLUSION: CF patients who have pancreatic insufficiency and carry mutations associated with a severe or a variable genotype are at increased risk to develop liver disease.

Adolescent↗