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J Peters

Publications and source records attributed to J Peters.

At least 55 records · Page 3Linked to original sources
PubMed2003

The 'TEI-index' is preload dependent and can be measured by transoesophageal echocardiography during mechanical ventilation.

BACKGROUND AND OBJECTIVE: The Doppler-derived echocardiographic TEI-index, defined as the sum of the left ventricular isovolumic contraction and isovolumic relaxation times divided by ejection time, quantifies combined systolic and diastolic ventricular functions. The index has been proposed to be independent of arterial pressure and heart rate, implying a broad clinical usefulness. However, it is unclear whether the index is preload independent. We assessed whether and to what degree the TEI-index is altered by left ventricular loading conditions, and the feasibility of measurement by transoesophageal echocardiography during anaesthesia and mechanical ventilation. METHODS: We studied 17 anaesthetized mechanically ventilated patients with coronary artery disease during variations in left ventricular preload evoked by head-up and head-down tilt, respectively. RESULTS: A head-down tilt increasing left ventricular end-diastolic area from 18.8 +/- 4 to 23.7 +/- 4 cm2 (P < 0.05) significantly decreased the TEI-index from 0.5 +/- 0.17 to 0.33 +/- 0.15 (P < 0.05). In contrast, the TEI-index remained unchanged with decreased left ventricular preload (14.4 +/- 3.7 cm2) during head-up tilt. CONCLUSIONS: An increase in preload decreases the TEI-index indicating its sensitivity to acute increases in left ventricular preload. The TEI-index can be measured perioperatively by transoesophageal echocardiography.

Analysis of Variance↗
PubMed2003

[Pain in patients with breast-conserving cancer treatment and radiotherapy].

In patients with breast-conserving surgery of carcinoma and radiotherapy pain rarely is an issue between patient and physician because the operation is considered to be well tolerable and radiotherapy to have few side- effects. There are very few data about frequency and management of pain in these patients. Therefore we evaluated a group of 180 patients after breast-conserving surgery during radiotherapy using a new Likert-scaled questionnaire. Data on the following items were collected: number of patients experiencing pain, pain attribution, frequency and intensity of pain, subjective evaluation and restriction in daily routine. Furthermore, we evaluated the side effects of radiation in an RTOG scale. 85% of patients had pain during radiation which by most was attributed to cancer treatment (surgery and radiation). More than 50% reported light to moderate pain during the entire six-week treatment. Thus pain is a more common symptom in breast cancer patients during radiation therapy than normally assumed and therefore should receive more attention by gynecologists and radiotherapists.

Adult↗
PubMed2003

[Blocking nociceptive afferents by retrobulbar bupivacaine does not decrease nausea and vomiting after propofol-remifentanil anaesthesia].

UNLABELLED: To test whether prophylactic neural blockade of noziceptive afferents or antiemetics diminutes postoperative nausea and vomiting (PONV) we studied in a randomised, prospective, and ouble-blind fashion 102 patients receiving implantation of an episcleral radioactive applicator for treatment of ocular malignant melanoma during remifentanil-propofol-anaesthesia. METHODS: 15 minutes prior to induction Dolasetron 12.5 mg (n = 18) or 50 mg (n = 20), Ondansetron 8 mg (n = 18), Droperidol 20 microg/kg (n = 23) or NaCl 0.9 % (n = 22) were randomly injected i.v. Furthermore, 4-8 ml Mepivacain 2 %/Bupivacain 0.5 % (n = 52) or saline (n = 50) were injected into the retrobulbar space after anaesthetic induction. Piritramid (0.1 mg/kg) was given for postoperative analgesia 30 minutes before end of surgery. Metamizol (1 g i.v.) and Dolasetron (12.5 mg i.v.) were provided on request as "rescue" medications. Variables were assessed by standardised questioning (NRS; yes/no) before and 1, 6, and 24 hours after surgery. STATISTICS: Chi(2)-, Mann-Whitney-U-, Kruskal-Wallis-test and logistic regression analysis, p < 0.05. RESULTS: Although retrobulbar anaesthesia decreased ocular pain (p = 0.013) and total postoperative complaints (p = 0.017) the incidence of PONV was not diminished. Droperidol was the only antiemetic to decrease PONV significantly (p = 0.001). CONCLUSIONS: Although prophylactic blockade of nozizeptive afferents by retrobulbar anesthesia decreased ocular pain and postoperative complaints, it failed to decrease the incidence of PONV. Thus, PONV after ocular surgery under propofol-remifentanil anaesthesia is not attenuated by preoperative blockade of noziceptive afferents. In patients undergoing total intravenous anaesthesia with propofol-remifentanil, droperidol prevented PONV more effectively than the used serotonin receptor antagonists.

Aged↗
PubMed2003

Emetic effects of morphine and piritramide.

BACKGROUND: Successful management of postoperative pain requires that adequate analgesia is achieved without excessive adverse effects. Opioid-induced nausea and vomiting is known to impair patients' satisfaction, but there are no studies providing sufficient power to test the hypothesis that the incidence of opioid-induced nausea and vomiting differs between micro -opioid receptor agonists. Thus, we tested the hypothesis that the incidence of vomiting and nausea differs between morphine and piritramide. METHODS: In a prospective, randomized, double-blind fashion, we administered either morphine (n=250) or piritramide (n=250) by patient-controlled analgesia (PCA) for postoperative pain relief. We used a bolus dose of 1.5 mg with a lockout time of 10 min. Incidence and intensity (numerical rating scale) of postoperative nausea, vomiting, pain, patient satisfaction (score 0-10), side-effects (score 0-3) and drug consumption were measured. RESULTS: Mean drug consumption did not differ between the piritramide and morphine groups (30.8 (SD 22.4) mg day(-1) vs 28.4 (21.8) mg day(-1)) during the first postoperative day and there were no significant differences in the overall incidence of nausea (30% vs 27%) and vomiting (19% vs 15%). Intensity of nausea correlated inversely (P=0.01) with morphine consumption but not with piritramide consumption. Pain scores both at rest (2.2 (1.9) vs 2.6 (2)) and during movement (4.4 (2.2) vs 4.9 (2.3)) were slightly but significantly less with morphine. CONCLUSIONS: Opioid-induced emesis was observed in about one-third of the patients using morphine and piritramide for PCA and the incidence of vomiting was one-half of that. Potential differences in the incidence of vomiting during PCA therapy between these micro-opioid receptor agonists can be excluded.

Adolescent↗
PubMed2003

The imprinted region on human chromosome 7q32 extends to the carboxypeptidase A gene cluster: an imprinted candidate for Silver-Russell syndrome.

Imprinted gene(s) on human chromosome 7q32-qter have been postulated to be involved in intrauterine growth restriction associated with Silver-Russell syndrome (SRS) as 7-10% of patients have mUPD(7). Three imprinted genes, MEST, MESTIT1, and COPG2IT1 on chromosome 7q32, are unlikely to cause SRS since epigenetic and sequence mutation analyses have not shown any changes. One hundred kilobases proximal to MEST lies a group of four carboxypeptidase A (CPA) genes. Since most imprinted genes are found in clusters, this study focuses on analysing these CPAs for imprinting effects based on their proximity to an established imprinted domain. Firstly, a replication timing study across 7q32 showed that an extensive genomic region including the CPAs, MEST, MESTIT1, and COPG2IT1 replicates asynchronously. Subsequently, SNP analysis by sequencing RT-PCR products of CPA1, CPA2, CPA4, and CPA5 indicated preferential expression of CPA4. Pyrosequencing was used as a quantitative approach, which confirmed predominantly preferential expression of the maternal allele and biallelic expression in brain. CPA5 expression levels were too low to allow reliable evaluation of allelic expression, while CPA1 and CPA2 both showed biallelic expression. CPA4 was the only gene from this family in which an imprinting effect was shown despite the location of this family of genes next to an imprinted cluster. As CPA4 has a potential role in cell proliferation and differentiation, two preferentially expressed copies in mUPD patients with SRS syndrome would result in excess expression and could alter the growth profiles of these subjects and give rise to intrauterine growth restriction.

Alternative Splicing↗
PubMed2003

A new system for regional citrate anticoagulation in continuous venovenous hemodialysis (CVVHD).

BACKGROUND: CVVHD is an established renal replacement therapy in hemodynamically unstable ICU patients. Various methods for regional citrate anticoagulation have been developed to minimize bleeding complications. Metabolic alkalosis, the risk of severe hypocalcemia and need for continuous calcium substitution as well as treatment-associated hypernatremia have limited the success of systems employed so far. We have developed a new technique for regional citrate anticoagulation in CVVHD to overcome these deficiencies and have performed a validation study. METHODS: One hundred and thirty-three filters with an overall treatment duration of 3,324 hours were used in 19 critically ill patients with bleeding complications. We used a calcium-containing dialysate (1.81 mmol/l Ca) to avoid mandatory systemic calcium supplementation. Sodium bicarbonate was added to the dialysate in variable concentrations (13 - 34 mmol/l) to control acid-base status and prevent hypernatremia. The resulting dialysate sodium concentrations were between 121 and 140 mmol/l. Blood flow was set at 75 ml /min. Infusion of a solution containing trisodium citrate and citric acid with an overall citrate concentration of 113 mmol/l was started at 250 ml/h. Primary endpoints were pre- and post-filter ionized calcium (Ca(i)) concentrations, base excess and serum sodium. Filter life was assessed as a secondary end-point. RESULTS: Control of electrolyte balance and azotemia was excellent (prefilter serum Ca(i) 1.06 +/- 0.012 mmol/l (+/- SEM), post-filter Ca(i) 0.23 +/- 0.01 mmol/l, base excess -0.39 +/- 0.4 mmol/l, serum sodium 137 +/- 4 mmol/l, mean serum creatinine 1.8 +/- 0.07 mg/dl). Normal base excess was achieved with a mean dialysate bicarbonate concentration of 26 mmol/l at a mean citrate infusion rate of 266 +/- 4 ml/h. After 48 hours, 25% of filters were still patent, mean filter life was 26 +/- 1.6 hours. No patient developed serious CVVHD-related adverse events. CONCLUSION: The new regional citrate anticoagulation system for CVVHD is safe, feasible and can avoid major complications of previously described methods, especially hypocalcemia, alkalosis and hypernatremia.

Acute Kidney Injury↗
PubMed2003

Subclinical hyperthyroidism in dementia and correlation of the metabolic index in FDG-PET.

AIM: Thyroid hormone status and thyroid antibodies were evaluated in patients suffering from dementia for further study of an association of hyperthyroidism with AD and vascular dementia (VD), respectively. PATIENTS: In 77 patients with dementia, and 42 controls, thyrotropin (TSH) and thyroid antibodies were correlated with the different types of dementia and the metabolic index (MI) based on imaging with F-18-2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET). RESULTS: Twenty-two of all patients with dementia (29%) had borderline (TSH 0.3-0.5 mU/l) or decreased TSH levels (TSH < 0.3 mU/L). TSH values were significantly lower in patients suffering from AD (median: 1.1 mU/l) and VD (0.5 mU/l) than in the control group (1.5 mU/l) (p < 0.01). Decreased or borderline TSH levels were present in 52% of the patients with VD, but in only 10% of the controls, and in 23% of the patients with AD. Antibodies to thyroid peroxidase were positive in 16% of all patients with dementia. The MI in patients suffering from AD with borderline TSH levels was 0.81 (0.70, 0.94). In contrast, patients suffering from AD with normal TSH values showed a slightly higher MI of 0.84 (0.76, 0.89) (p = n.s.). CONCLUSION: Decreased or borderline TSH values are associated with an increased probability of having dementia, especially VD.

Aged↗
PubMed2002

Clinical experience with quinupristin-dalfopristin as rescue treatment of critically ill patients infected with methicillin-resistant staphylococci.

OBJECTIVES: To describe the efficacy and safety of quinupristin-dalfopristin (Q-D) as rescue therapy in critically ill patients with severe infections caused by methicillin-resistant staphylococci unresponsive to vancomycin treatment. DESIGN: Observational study in the context of the compassionate use programme for Q-D. METHODS: Twelve mechanically ventilated patients suffering from severe staphylococcal infections, pretreated unsuccessfully with vancomycin despite in vitro sensitivity, were included. Patients received, intravenously, Q-D 7.5 mg/kg body weight 3 times daily. The duration of Q-D therapy averaged 11.8 days (range: 1-26 days). The outcome variables were clinical efficacy and bacteriological eradication. RESULTS: Methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE) were isolated in three patients each, and both bacteria were isolated from six patients. Eradication of pathogen(s) was achieved in 7 of 12 patients (66%). Five patients (42%) died due to severe co-morbidity. Adverse events related to Q-D were not observed and neither renal nor liver function was adversely affected. CONCLUSIONS: Quinupristin-dalfopristin appears to be an efficient and safe antimicrobial drug for the rescue treatment of staphylococcal infections in critically ill patients. It may be considered as a treatment option in cases of vancomycin treatment failure.

Adult↗
PubMed2002

Expression of CXC chemokine IP-10 in testicular germ cell tumours.

Tumour-infiltrating T lymphocytes (TILs) possess discrepant properties ranging from anti- to protumour activities. Understanding precisely which mechanisms navigating T lymphocytes into the tumour site will help to further the anti-tumour or to disrupt the pro-tumour activities of TILs. The present study asked what enables TILs to migrate into testicular germ cell tumours (TGCTs). TILs were characterized and the expression of a large panel of T-lymphocyte-attracting chemokines was investigated in 21 TGCT cases. Flow cytometry revealed that approximately 80% of TGCT-infiltrating T lymphocytes express CXCR3, a receptor for the chemokine interferon-inducible protein-10 (IP-10). RT-PCR and immunohistochemistry indicated that IP-10 was the only chemokine investigated which was constantly expressed in TGCT. As IP-10 was found to be expressed by endothelial cells of TGCT-associated blood vessels, the question arose whether the IP-10-regulating cytokine interferon-gamma (IFNgamma) is produced by tumour cells and if so, whether tumour-derived IFNgamma can induce IP-10 in endothelial cells. Applying in situ hybridization, IFNgamma transcripts were found in neoplastic germ cells. Analyses of two TGCT cell lines indicated that the tumour cells not only express IFNgamma mRNA, but also produce and secrete IFNgamma protein; tumour-derived IFNgamma provokes IP-10 expression and secretion by endothelial cells in vitro, as assessed by PCR and ELISA. Together, the data suggest that neoplastic germ cells secret IFNgamma and thereby stimulate tumour-associated endothelial cells to express IP-10, which contributes to the recruitment of CXCR3+ T lymphocytes to the site of TGCTs.

Adult↗
PubMed2002

Notched ureter sign.

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Diagnosis, Differential↗
PubMed2002

Effects of cysteine protease inhibitors on oviposition rate of the western flower thrips, Frankliniella occidentalis.

Proteolytic activity in whole insect extracts of the western flower thrips, Frankliniella occidentalis, was found to belong predominantly to the class of cysteine proteases. The pH optimum of the general proteolytic activity was determined to be 3.5, which is low when compared to other insects using cysteine proteases for protein digestion. The proteinaceous cysteine protease inhibitors chicken cystatin, potato cystatin and sea anemone equistatin inhibited in vitro more than 90% of the protease activity. To test in vivo the biological effect of such inhibitors on the oviposition rate of western flower thrips, recombinant potato cystatin and equistatin were fed to adult females. A gradual reduction in oviposition rate to about 45% of control was observed when reared on these PIs for a period of 5 days, with no increase in mortality. These results are discussed in the light of the application of protease inhibitors in transgenic plants to control this insect pest.

Journal Article↗
PubMed2002

Pitfall in insertion of suprapubic catheter in patients with spinal cord injuries.

OBJECTIVE: To report an unusual presentation of a misplaced suprapubic catheter (SPC) in a spinal cord injury (SCI) patient. DESIGN: A case report of a SCI patient in whom a SPC was 'partially misplaced' in an emergency. SETTING: London Spinal Injuries Unit, Stanmore, UK. SUBJECT: A 33-year-old man who sustained a C5 SCI in a road traffic accident 6 months ago. He had an indwelling urethral catheter, which blocked off and repeated attempts to reinsert another one per urethra were unsuccessful. MAIN OUTCOME MEASURE: A SPC was inserted in an emergency at the bedside, as he developed autonomic dysreflexia. The catheter initially drained clear urine but subsequently the flow became intermittent. He also started complaining of lower abdominal discomfort. RESULTS: The abdominal examination was unremarkable without signs of peritonism. An ultrasound scan of the abdomen revealed the eye of the catheter in the bladder but the balloon had been inflated in the subcutaneous tissues. It was reinserted under cystoscopic control in the operating theatre. CONCLUSION: The insertion of a SPC in a neuropathic patient can be a challenge even for an experienced urologist. As these patients often have small capacity bladders, the SPC should be inserted under cystoscopic control wherever possible. However if they are inserted blindly there should be a high index of suspicion for the potential complication of a misplaced catheter. The patient should undergo regular abdominal examination and an ultrasound scan should be performed as soon as possible for confirmation.

Abdominal Pain↗
PubMed2002

The management of low-flow priapism with the immediate insertion of a penile prosthesis.

OBJECTIVE: To evaluate the outcome of patients undergoing the immediate insertion of a penile prosthesis as a treatment for acute low-flow priapism. PATIENTS AND METHODS: Eight patients presenting with low-flow priapism with a mean duration of 91 h (range 32-192) were prospectively evaluated. All had failed conservative management with the instillation of alpha-adrenergic agents, and four had already undergone shunt procedures elsewhere. Immediate management consisted of the insertion of a malleable prosthesis in six patients and an inflatable prosthesis in two. One of the malleable prostheses was subsequently changed to an inflatable device. RESULTS: There were no early complications, with all patients being satisfied with the end result, and seven having sexual intercourse. One patient developed a penile deformity after surgery, cause by fibrosis around one inflatable cylinder. All patients have maintained their penile length. CONCLUSIONS: Prolonged low-flow priapism results in a variable degree of cavernosal fibrosis and a subsequent loss of penile length. The delayed insertion of a penile prosthesis can be difficult, with high complication rates. The immediate insertion of a penile prosthesis in patients with prolonged low-flow priapism is simple and maintains penile length. This should always be offered to the patient at initial presentation, as the complication rate is low and the subsequent outcome excellent.

Adult↗
PubMed2002

[Etiology and pathogenesis of Alzheimer dementia].

Alzheimer's disease (AD) is the most common cause of primary dementia, characterized by a progressive process of pathophysiological restructuring of the brain over decades. The hallmark of Alzheimer's disease is the extracellular accumulation and deposition of insoluble amyloid, to be found in the parenchyma in the form of amyloid plaques and in meningeal and cerebral vessels as a congophile angiopathy. Equally conspicuous is the intraneuronal occurrence of neurofibrillary tangles, consisting mainly of hyperphosphorylated tau-protein. Amyloid plaques and neurofibrillary tangles are characteristic, but not specific to Alzheimer's disease. Similar changes can be found in healthy ageing processes and in various other neurodegenerative diseases. It is common to differentiate between an early-onset, familial Alzheimer's disease with an established genetic etiology, representing only about 5% of all cases, and the more typical late-onset, sporadic Alzheimer's disease with an age of onset above 65 years and no clear pattern of inheritance. Although there seems to be a large heterogeneity in the etiology of Alzheimer's disease, the amyloid-cascade-hypothesis has taken a central position as a model for the general etiopathogenesis. The regulation of amyloid plaques underlies a diversity of cellular and molecular factors. In addition to ageing, apolipoprotein E 4 is a firmly established risk factor. Disturbance in the cerebral glucose metabolism, especially in the hippocampal regions, is a further proposed factor in the pathogenesis of Alzheimer's disease. The wide-spread loss of cortical cholinergic neurotransmission associated with the cognitive deficits is of importance to the comprehension of the symptoms and the present pharmacotherapy of Alzheimer's disease.

Alzheimer Disease↗
PubMed2002

Resistance to rocuronium in a child with Schwartz-Jampel syndrome type 1 B.

In Schwartz-Jampel syndrome micrognathia and jaw muscle rigidity may result in difficult or impossible tracheal intubation. Since the dose-response relationship to muscle relaxants is unknown in this rare disease we assessed by mechanomyography the neuromuscular response to the rocuronium in a two-year-old child with Schwartz-Jampel syndrome (SJS) Type 1 B. Rocuronium's dose-response curve was markedly shifted (3.5-fold dose) to the right when compared to healthy children and intubation conditions were improved. This resistance to NDMR may result from a lower acetylcholine degradation rate suggested as being the consequence of mutation of the gene encoding perlecan (HSPG2) in SJS. Thus, considerably higher doses of NDMR than usual may be required for facilitation of tracheal intubation in patients with SJS. Since evidence for genetic heterogeneity of SJS exists we also recommend incremental doses of a rapidly acting NDMR with continuous monitoring of neuromuscular function so as to assess the optimum relaxant dose.

Androstanols↗
PubMed2002

[Mammographic positioning: how does it affect the gynecologist?].

High quality in breast imaging is of utmost importance for early diagnosis of breast cancer. Conventional x-rays are usually taken in 2 perpendicular views. This technique allows precise spacial localization of pathologic findings. Since 1983 mediolateral oblique (MLO) instead of mediolateral (ML)-projections have been recommended because they supposedly include more of the axillary tail of breast tissue. This makes sure that more carcinomas located in the axillary tail of breast tissue are detected. It is planned that MLO-positioning will be required as European quality standard for mammography. Our investigations show, however, that the MLO-projection has a number of distinct disadvantages that need to be discussed. Only 7 % of women at the most have an axillary tail demanding MLO positioning. Precise localization of a tumor is not possible anywhere in the breast if an MLO-projection is used. MLO positioning furthermore causes faese positives, so-called pseudolesions that demand further work-up. Radiotherapy is difficult because the tumorbed cannot be localized and thus precise saturation is not possible.

Breast↗
PubMed2002

Optimal rocuronium dose for intubation during inhalation induction with sevoflurane in children.

BACKGROUND: We studied 120 children aged 2-7 yr in a prospective, randomized, assessor-blinded fashion to define the optimal rocuronium dose which provides a 95% probability of acceptable intubation conditions (ED95TI) during inhalation induction with sevoflurane. METHODS: After inhalation induction with 8% sevoflurane in 60% nitrous oxide and 40% oxygen, and loss of the eyelash reflex, we administered rocuronium (0.1, 0.15, 0.22, 0.3, or 0.6 mg kg-1) or placebo. We quantified neuromuscular function by stimulation of the ulnar nerve at 0.1 Hz to produce contraction of the adductor pollicis muscle using accelerometry. Intubation conditions were assessed 2 min after test drug injection. The optimal rocuronium dose was defined as the lowest dose, which allowed acceptable intubation conditions in 95% of children (ED95TI). RESULTS: Two minutes after injection of placebo or rocuronium, intubation conditions were acceptable in 35, 45, 80, 90, 95, and 100% of children, respectively. Rocuronium 0.07 [CI 0.02-0.11], 0.24 [0.19-0.31], and 0.29 [0.23-0.38] mg kg-1 provided 50, 90, and 95% probability of acceptable intubating conditions. When thumb acceleration was depressed by 50% or more, intubating conditions were considered acceptable in 97% of children. Recovery of the train-of-four ratio to 0.8 averaged 12 (7), 16 (7), 24 (7), 24 (8), and 50 (22) min after the respective dose of rocuronium. CONCLUSIONS: During inhalation induction with 8% sevoflurane in 60% nitrous oxide, rocuronium 0.29 mg kg-1 (ED95) optimizes intubation conditions for surgery of short duration.

Androstanols↗