PubMed Health⌕ Search

Biomedical subjects

M Oertel

Publications and source records attributed to M Oertel.

At least 19 recordsLinked to original sources
PubMed2006

Chiari malformation type I with concomitant persistent trigeminal artery -- report of an unusual case and a review of the current literature.

BACKGROUND: Chiari malformation type I is a stenosis of the subarachnoid space at the level of the foramen magnum due to a small posterior fossa and herniation of the cerebellar tonsils. We present here the unusual case of a Chiari malformation in conjunction with a persistent trigeminal artery and hypoplasia of the basilar artery, also known as a Saltzman anomaly. CASE REPORT: A 34-year-old female physician presented with recurrent headaches, bilateral weakness of deltoid muscles and numbness of the fingertips 3 to 5. A cranial MRI revealed a descent of the cerebellar tonsils to the level of C2 and a supracerebellar cyst. During surgery, a decompressive suboccipital craniectomy was performed. The supracerebellar cyst was fenestrated and the cerebellar tonsils were resected bilaterally. Two days after surgery the patient developed cranial nerve dysfunction and a right-sided hemiparesis. Cerebral angiography revealed a Saltzman type 1 anomaly with persistent primitive trigeminal artery and hypoplasia of the basilar artery. DISCUSSION: This is the first report in the literature about the coincidence of both unusual anomalies. The latest literature of both rare anatomy and the unusual clinical course will be discussed.

Adult↗
PubMed2004

Treatment of pain from osteoporotic vertebral collapse by percutaneous PMMA vertebroplasty.

BACKGROUND: Vertebral compression fractures are common complications in advanced osteoporosis. In general, this disease of the elderly patient is characterized by severe local back pain. Pathophysiologically, bony instability triggers local pain during body movement. Serious pain immobilizes the patients and forces them to bed rest. As a result, complications like thrombosis or pneumonia occur. Invasive treatment with surgical instrumentation for vertebral stabilization is not indicated in elderly patients especially with additional diseases. The purpose of this study was to test the hypothesis that percutaneous polymethylmethacrylate (PMMA) vertebroplasty significantly reduces pain due to vertebral collapse in osteoporotic patients and improves quality of life. METHODS: A total of 38 patients with osteoporotic vertebral compression fractures of the thoracic and lumbar spine were treated by PMMA vertebroplasty. After admission, before discharge from the hospital, six weeks, half a year and one year later patients answered the Oswestry Low Back Pain Disability (OLBPD) Questionnaire for assessment of treatment related change in disability. In all patients percutaneous vertebroplasty was performed under local anesthesia. FINDINGS: A total of 92% of patients reported a significant pain reduction immediately after treatment. Also one year after vertebroplasty pain remained significantly reduced. Vertebroplasty was highly beneficial for patients with pain related to local instability of the spine. Extravasation of PMMA beyond the vertebral margins was observed in 26% of the cases. No treatment related clinical or neurological complications were noticed. INTERPRETATION: PMMA vertebroplasty is a useful and safe method of pain relief which rapidly regains quality of life for patients with osteoporotic vertebral compression.

Administration, Cutaneous↗
PubMed2004

Outcome and prognostic factors of hemicraniectomy for space occupying cerebral infarction.

OBJECTIVE: To determine long term functional outcome and length of survival of patients undergoing decompressive craniectomy for space occupying infarction of the middle cerebral artery (MCA), and to identify risk factors associated with death and unfavourable outcomes METHODS: Databases of patients undergoing decompressive craniectomy for space occupying MCA infarction compiled at eight neurosurgical departments (1996-2001) were merged, and 188 patients were evaluated. Mortality was calculated by the Kaplan-Meier method. Clinical outcome was rated using the Glasgow outcome scale (GOS). The prognostic impact of patient related covariates on length of survival and the GOS was analysed multivariately. RESULTS: The unadjusted 3, 6, and 12 month mortality rates were 7.9%, 37.6%, and 43.8%, respectively (median follow up, 26 weeks). In the "best" multivariate model, age >50 years (p<0.02) and the involvement of two or more additional vascular territories (p<0.01) had an unfavourable impact on length of survival. The adjusted six month mortality was as low as 20.0% (no risk factor) and as high as 59.7% (two risk factors). A GOS score of 50 years (p<0.0003): 34.9% of the patients 3, as compared with 12.0% of the elderly subpopulation. The side of the infarct did not have prognostic relevance. CONCLUSIONS: Results of surgical treatment in patients <50 years of age undergoing decompressive craniectomy are encouraging. The effectiveness of decompressive craniectomy for patients >50 years remains questionable and should be analysed in the framework of a prospective randomised study.

Adolescent↗
PubMed2003

[Polymethylmethacrylate-vertebroplasty. A new and effective method of pain treatment in vertebral compression].

BACKGROUND AND OBJECTIVE: Percutaneous polymethylmethacrylate (PMMA) vertebroplasty is increasingly used in the treatment of back pain related to compression of the vertebral bodies. After the procedure immediate mobilization of the patient is possible. The purpose of the study was to examine the change in quality of life of patients with vertebral collapse achieved by vertebroplasty during a six-month period. PATIENTS AND METHODS: 28 patients with osteolytic metastases (mean age 59,7 +/- 7,8 years, 2,1:1male/female ratio) and 38 patients with osteoporotic vertebral collapse (mean age 73 +/- 6 years, 1:3,5male/female ratio ) of the thoracal and lumbar spine were treated with PMMA vertebroplasty and analysed prospectively. After admission, before, six weeks and 6 months after discharge from the hospital patients answered the Oswestry Low Back Pain Disability (OLBPD) questionnaire for assessment of treatment-related changes in disability. RESULTS: Immediately and 6 months after treatment 83 % of tumor patients and 92 % of ostoporotic patients had significant pain reduction. Extravasation of PMMA beyond the vertebral margins were observed in 26 % of the patients. No treatment-related clinical or neurological complications were observed. CONCLUSION: PMMA vertebroplasty is an efficacious and safe method of pain relief for patients with osteolytic metastases or osteoporotic compression with good long-term results.

Aged↗
PubMed2002

Is CPP therapy beneficial for all patients with high ICP?

Induced blood pressure elevation has become a popular treatment for intracranial hypertension. However, there remains a concern that in some patients blood pressure elevation will further elevate ICP. This study was conducted to test the hypothesis that increasing MAP decreases ICP. A total of 47 studies were performed on 23 intubated patients with head injury. MAP and SjvO2 were continuously monitored. MAP was raised significantly by 13.8 (5.9) mmHg (t-test; p < 0.0001) using phenylephrine infusion. The percent change ICP per mmHg increase in MAP (% delta ICP/mm Hg MAP) was calculated. Pearson correlation coefficient, t-test and logistic regression analysis were used for statistical evaluation. Increasing MAP resulted in a decrease in ICP in 38.3% and in an increase in ICP in 61.7% out of 47 studies. The following characteristics were seen in patients in whom a decrease in ICP was associated with an increase in MAP: High GCS (r = -0.61; p = 0.004) and low SjvO2 ((2 = 4.89; p = 0.027). In patients with lower GCS and high SjvO2 an increase in MAP resulted in an increase in ICP. We concluded that in the majority of studies increasing MAP was followed by an increase in ICP. CPP therapy has a selective indication in patients with high GCS, low SjvO2 and increased ICP.

Anticonvulsants↗
PubMed2002

Metabolic suppressive therapy as a treatment for intracranial hypertension--why it works and when it fails.

Thirty years after its first description metabolic suppressive therapy is still controversial in patients with intractable intracranial hypertension. In this study high dose propofol was used to induce metabolic suppression. The effects on intracranial pressure (ICP) and the cerebral metabolic rates for oxygen and glucose (CMRO2 and CMRGlc) are reported. A total of 28 studies were performed on 14 head injured patients. A Xenon133 cerebral blood flow (CBF) and a CO2-reactivity (CO2R) test were performed prior to induction of metabolic suppression. The following parameters were continuously monitored: EEG, etCO2, SjvO2, ICP, MAP and bilateral MCA flow velocity (VMCA). PCO2 was obtained before and during propofol-induced EEG burst-suppression in arterial and jugular-venous blood. CMRO2, CMRGlc and Metabolic Ratio (MR = CMRO2/CMRGlc) were calculated. MR < 0.6 was defined as relative hyperglycolysis. ICP decreased by 24.1 +/- 29.0% during burst-suppression. Arterial, jugular-venous and etCO2 also decreased. Multiple regression analysis revealed that CO2 was the strongest predictor for ICP. Lower baseline ICP and normal CO2 reactivity were predictors for normal metabolic suppression reactivity. In studies with normal metabolic ratio, ICP reduction was associated with a reduction in CMRO2. In studies with hyperglycolysis, ICP reduction was poor but CMRGlc decreased significantly. In conclusion, intact CO2R, normal or only moderately elevated ICP and normal MR are predictive of ICP reduction with high dose propofol after head injury.

Anticonvulsants↗
PubMed2002

Can hyperventilation improve cerebral microcirculation in patients with high ICP?

Gosling's pulsatility index (PI) is generally thought to reflect cerebrovascular resistance. Hyperventilation and increased intracranial pressure (ICP) usually increase PI. In this study, the effect of hyperventilation on PI was assessed in head injured patients with and without elevated ICP. A total of 73 hyperventilation studies were conducted on 20 intubated TBI patients. EtCO2, ICP, MCA flow velocity and MCA PI bilaterally were recorded simultaneously. Hemispheric CO2-Reactivity (hCO2R) was calculated. Only studies with a baseline ICP < 15 or > 30 mm Hg were included for analysis. With hyperventilation pCO2 decreased on average from 33.54.2 to 26.84.8 mmHg. PI increased significantly in patients with baseline ICP < 15 mmHg (11.8%; p < 0.0001) but decreased significantly if baseline ICP was > 30 mm Hg (12.21%; p = 0.0013). High baseline ICP, low initial GCS and impaired hCO2R were associated with the decrease of PI. Hyperventilation unexpectedly reduced PI in patients with high ICP. Because decreased PI suggests decreased CVR, it is postulated that hyperventilation in the setting of raised ICP improves cerebral microcirculation.

Adult↗
PubMed2001

Alloreactivity of natural killer cells in allogeneic liver transplantation.

BACKGROUND: The cytolytic attack of natural killer (NK) cells is blocked by recognition of the idiotypic phenotype of certain polymorphisms in HLA class I molecules, specifically by HLA-C alleles (Asn77, Lys80 or Ser77, Asn80) or HLA-Bw4 allotypes. Because liver allograft rejection is associated closer with mismatch in HLA class I than class II, we investigated the role of NK cells in acute hepatic allograft rejection in vivo/in vitro. METHODS: The HLA pattern was typed with serological and polymerase chain reaction (PCR) techniques. In 31 liver transplantations, mononuclear cells from donor spleen and peripheral blood of recipients (before/after transplantation) were cultured in mixed lymphocyte cultures (MLC). MLC-derived effector cells were analyzed by flow cytometry and tested in 51Cr-release assays. RESULTS: Patients with NK allospecific constellations tended to have higher numbers of NK cells in peripheral blood during the first 4 weeks after transplantation, and patients' lymphocytes stimulated with donor cells had a significantly higher cytotoxic activity on days 14 and 21 compared with patients without NK allospecificity. However, acute rejection occurred with similar frequency in both groups (31% with allospecific constellations vs. 40% without). Moreover, acute rejection episodes were not associated with an increase in NK cells in vivo or enhanced cytotoxicity of NK cells to donor target cells. CONCLUSIONS: Under standard immunosuppressive therapy, NK allospecific constellations did not seem play a major role in acute hepatic allograft rejection. Strategies to prevent or treat NK allospecific constellations after liver transplantation are not likely to reduce the incidence or severity of acute allograft rejection.

Acute Disease↗
PubMed2001

The novel ependymin related gene UCC1 is highly expressed in colorectal tumor cells.

Normal cells differ from malignant tumor cells in the transcription levels of many different genes. Two colorectal tumor cell lines were compared with a normal colorectal cell line by differential display reverse transcription PCR to screen for tumor cell specific differentially transcribed genes. By this strategy the upregulation of a novel gene was detected designated as 'upregulated in colorectal cancer gene-1' (UCC1). The UCC1 gene transcript level is increased in cultured tumor cells and in two out of three analyzed colorectal tumor tissue specimens compared to normal cultured cells and to corresponding normal tissue samples. Remarkably, the UCC1 protein shows significant sequence similarity to the highly divergent piscine glycoproteins termed ependymins which are synthesized by leptomeningeal fibroblasts and secreted into the cerebrospinal fluid.

Amino Acid Sequence↗
PubMed2001

Trefoil factor family-peptides promote migration of human bronchial epithelial cells: synergistic effect with epidermal growth factor.

A process termed "restitution" enables rapid repair of the respiratory epithelium by migration of neighbouring cells. Mucin-associated TFF-peptides (formerly P-domain peptides or trefoil factors) are typical motogens enhancing migration of cells in various in vitro models mimicking restitution of the intestine. The human bronchial epithelial cell line BEAS-2B was used as a model system of airway restitution. The motogenic activities of recombinant human TFF2 as well as porcine TFF2 were demonstrated by in vitro wound healing assays of BEAS-2B cells. TFF2 did not induce phosphorylation of the epidermal growth factor (EGF) receptor. EGF was capable of enhancing the motogenic effect of human TFF2 at a concentration of 3 x 10(-10) M whereas EGF itself (i.e., in the absence of TFF2) did not stimulate migration at this low concentration. Furthermore, TFF2 as well as monomeric and dimeric forms of TFF3 enhanced migration of BEAS-2B cells in Boyden chambers. Motogenic activity of TFF2 was also shown for normal human bronchial epithelial (NHBE) cells in Boyden chambers. These results suggest that TFF-peptides act as motogens in the human respiratory epithelium triggering rapid repair of damaged mucosa in the course of airway diseases such as asthma.

Bronchi↗
PubMed2001

Carbon dioxide reactivity, pressure autoregulation, and metabolic suppression reactivity after head injury: a transcranial Doppler study.

OBJECT: Contemporary management of head-injured patients is based on assumptions about CO2 reactivity, pressure autoregulation (PA), and vascular reactivity to pharmacological metabolic suppression. In this study, serial assessments of vasoreactivity of the middle cerebral artery (MCA) were performed using bilateral transcranial Doppler (TCD) ultrasonography. METHODS: Twenty-eight patients (mean age 33 +/- 13 years, median Glasgow Coma Scale score of 7) underwent a total of 61 testing sessions during postinjury Days 0 to 13. The CO2 reactivity (58 studies in 28 patients), PA (51 studies in 23 patients), and metabolic suppression reactivity (35 studies in 16 patients) were quantified for each cerebral hemisphere by measuring changes in MCA velocity in response to transient hyperventilation, arterial blood pressure elevation, or propofol-induced burst suppression, respectively. One or both hemispheres registered below normal vasoreactivity scores in 40%, 69%, and 97% of study sessions for CO2 reactivity, PA, and metabolic suppression reactivity (p < 0.0001), respectively. Intracranial hypertension, classified as intracranial pressure (ICP) greater than 20 mm Hg at the time of testing, was associated with global impairment of CO2 reactivity, PA, and metabolic suppression reactivity (p < 0.05). A low baseline cerebral perfusion pressure (CPP) was also predictive of impaired CO2 reactivity and PA (p < 0.01). Early postinjury hypotension or hypoxia was also associated with impaired CO2 reactivity (p < 0.05), and hemorrhagic brain lesions in or overlying the MCA territory were predictive of impaired metabolic suppression reactivity (p < 0.01). The 6-month Glasgow Outcome Scale score correlated with the overall degree of impaired vasoreactivity (p < 0.05). CONCLUSIONS: During the first 2 weeks after moderate or severe head injury, CO2 reactivity remains relatively intact, PA is variably impaired, and metabolic suppression reactivity remains severely impaired. Elevated ICP appears to affect all three components of vasoreactivity that were tested, whereas other clinical factors such as CPP, hypotensive and hypoxic insults, and hemorrhagic brain lesions have distinctly different impacts on the state of vasoreactivity. Incorporation of TCD ultrasonography-derived vasoreactivity data may facilitate more injury- and time-specific therapies for head-injured patients.

Adolescent↗
PubMed2000

Acute rejection of hepatic allografts from HLA-DR13 (Allele DRB1(*)1301)-positive donors.

Acute rejection of hepatic allografts does not show consistent association with the number of mismatches of HLA classes I and II. Therefore, we investigated the relation between specific donor or recipient HLA antigens and the occurrence of acute rejection. HLA typing of 35 liver transplant recipients and donors was performed by serological standard technique, with confirmation and subtyping by polymerase chain reaction with sequence-specific primers. HLA class I antigens were not associated with the occurrence of acute rejection. The graft was positive for HLA-DR13 in 8 of 13 transplant recipients (62%) with acute rejection, but only 4 of 22 recipients (18%; P =.024; P(Bonferroni-corrected) =.33, not significant) without rejection. The graft was positive for DRB1*1301 in 7 of 13 recipients (54%) with acute rejection, but only 1 of 22 recipients (5%) without rejection (P =.002; P(Bonferroni-corrected )=.028). This patient had experienced long-lasting bacterial sepsis, which markedly reduced the risk for acute rejection. We speculate that the expression of donor DRB1*1301 (if mismatched) may increase the risk for acute hepatic allograft rejection.

Acute Disease↗
PubMed2000

Altered function of the hypothalamic stress axes in patients with moderately active systemic lupus erythematosus. I. The hypothalamus-autonomic nervous system axis.

OBJECTIVE: To determine the human corticotropin releasing hormone (hCRH) induced stress response of the hypothalamus-autonomic nervous system axis (HANS) in patients with moderately active systemic lupus erythematosus (SLE). METHODS: Cardiovascular and pupillary function variables were measured by standardized computer procedures before and during an hCRH test (6 time points). The results of 12 patients with SLE were compared to 24 healthy subjects with (HS+P, n = 12) and without (HS, n = 12) prior administration of prednisolone 3 days before the test. RESULTS: At baseline, diastolic blood pressure was significantly higher in SLE than in HS or HS+P (p<0.001). During the hCRH test, patients with SLE had increased heart rates and systolic and diastolic blood pressure responses compared to HS+P and HS (p<0.001 for all comparisons). Moreover, heart rate variation was decreased at rest, during the lying-to-standing procedure, and during the 2 applied respiratory tests (p<0.01 vs. HS). Compared to HS+P and HS, latency time of the pupillary light reflex was prolonged and maximal pupillary area was increased, revealing sympathetic hyperreactivity. CONCLUSION: This study found an altered autonomic nervous system response at baseline, which was more pronounced during the hCRH stress test in patients with moderately active SLE compared to healthy subjects. Baseline and stress responses are characterized by a sympathetic overstimulation. Such a hypersympathetic reaction may lead to increased risk of cardiovascular diseases in patients with moderately active SLE, which needs to be investigated in longitudinal studies.

Adrenocorticotropic Hormone↗
PubMed2000

Altered function of the hypothalamic stress axes in patients with moderately active systemic lupus erythematosus. II. Dissociation between androstenedione, cortisol, or dehydroepiandrosterone and interleukin 6 or tumor necrosis factor.

OBJECTIVE: To investigate adrenocorticotropin, androstenedione (ASD), cortisol, or dehydroepiandrosterone sulfate (DHEAS) before and during a corticotropin releasing hormone (hCRH) test in patients with moderately active systemic lupus erythematosus (SLE) undergoing low dose longterm glucocorticoid therapy, and to examine these hormones in relation to interleukin 6 (IL-6) or tumor necrosis factor (TNF). METHODS: Serum levels of hormones and cytokines were measured before and during an hCRH test. The results of 12 patients with SLE were compared to 12 healthy subjects (HS) and 12 healthy subjects given prior short term prednisolone (HS+P). RESULTS: Baseline and stimulated serum ASD, cortisol, and DHEAS were lower in patients with SLE vs. HS (p<0.005), but baseline and stimulated plasma adrenocorticotropin was normal in SLE. In SLE, but not in HS+P or HS, baseline and stimulated DHEAS was low in relation to cortisol or ASD (i.e., shift from DHEAS to cortisol or ASD). In patients with SLE, baseline and stimulated serum levels of adrenal hormones were lower in relation to IL-6 or TNF compared to HS or HS+P (p< 0.001). In contrast, in SLE patients, the baseline and stimulated pituitary hormone adrenocorticotropin was normal in relation to these cytokines. CONCLUSION: We found marked adrenal insufficiency and a shift in steroidogenesis to cortisol in patients with SLE, but a completely normal pituitary function (in absolute values and in relation to IL-6 or TNF). This may depend in part on prior longterm glucocorticoid therapy and changes of steroidogenesis due to cytokines. The situation in patients with SLE was not mimicked by high dose short term prednisolone in healthy subjects. Further longitudinal studies in untreated patients are needed to investigate the endocrine-immune interplay and its consequences during the course of SLE.

Adrenocorticotropic Hormone↗
PubMed1999

Structure of the Xenopus laevis TFF-gene xP4.1, differentially expressed to its duplicated homolog xP4.2.

TFF-peptides (formerly P-domain peptides, trefoil factors) represent major secretory products of mucous epithelia in mammals and amphibia. The nucleotide sequence of a large portion of a gene encoding the TFF-peptide xP4.1 from Xenopus laevis and its genomic organization were determined in the present study. The peptide xP4.1 containing four TFF-domains is thought to represent the functional frog homolog of human TFF2 (formerly hSP). The xP4.1 gene analyzed spans a region of about 7 kb and consists of six exons. Each TFF-domain is encoded by a single exon flanked by type 1 introns typical of shuffled modules. The 5'-upstream region contains a TATA-box, and potential binding sites for hepatocyte nuclear factor 3 and AP-1. Furthermore, the cDNA sequence of a transcript named xP4.2 with 91% similarity to xP4.1 is presented. RT-PCR analysis revealed that xP4.1 and xP4.2 genes are differentially expressed. xP4.1 transcripts are detectable only in the stomach, but not in the esophagus, whereas xP4.2 transcripts are found both in the esophagus and in the stomach with a descending gradient from fundus to antrum.

Amino Acid Sequence↗
PubMed1995

Differential selenium-dependent expression of type I 5'-deiodinase and glutathione peroxidase in the porcine epithelial kidney cell line LLC-PK1.

The Se-dependent expression of two selenoproteins, cytosolic glutathione peroxidase (cGPx) and type I iodothyronine-5'-deiodinase (5'DI), was investigated in the porcine epithelial kidney cell line LLC-PK1 in serum-free medium. The selenite-dependent expression of cGPx and 5'DI was revealed by enzyme-activity measurements, affinity labelling of 5'DI, metabolic labelling of proteins with 75Se and steady-state mRNA analysis. The expression of the two enzymes strongly depended on selenite concentrations of the culture medium. cGPx required 2-fold higher selenite levels than 5'DI to reach half-maximal activity. The Se-dependent enzyme activities were approximately paralleled by the corresponding steady-state mRNA levels. The response of the two enzymes to Se supply was further characterized by kinetic Se-depletion and -repletion experiments. Upon removal of medium selenite, cGPx activity decreased exponentially, whereas after an initial decrease over 1-2 days, 5'DI levels completely recovered during a further 2 days. These data indicate a differential Se-dependent regulation of the two selenoproteins, with 5'DI being preferentially supplied with the trace element Se, thus ensuring a continuous cellular capacity for thyroid-hormone activation, even under Se-deficient conditions. The abundant cGPx in cells with sufficient Se supply might serve as a cellular Se store which can be mobilized for the synthesis of more vital selenoproteins such as 5'DI under shortage conditions. Thus, a cellular hierarchy of selenoprotein expression, reflected by different individual regulation mechanisms at the transcriptional and post-transcriptional level, adds to the previously recognized tissue-specific hierarchy of Se retention.

Animals↗