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H Wilkens

Publications and source records attributed to H Wilkens.

At least 37 records · Page 2Linked to original sources
PubMed2000

A comparison of the acute hemodynamic effects of inhaled nitric oxide and aerosolized iloprost in primary pulmonary hypertension. German PPH study group.

OBJECTIVE: We sought to compare the acute hemodynamic effects of inhaled nitric oxide (NO) and aerosolized iloprost in primary pulmonary hypertension (PPH). BACKGROUND: Inhalation of the stable prostacyclin analogue iloprost has recently been described as a novel therapeutic strategy for PPH and may offer an alternative to continuous intravenous infusion of prostacyclin or inhalation of NO. METHODS: During right heart catheterization, 35 patients with PPH sequentially inhaled 40 ppm of NO and 14 to 17 microg of iloprost, and the effects on hemodynamics and blood gases were monitored. RESULTS: Both NO and iloprost caused significant increases in cardiac output, mixed-venous oxygen saturation and stroke volume as well as significant decreases in pulmonary artery pressure and pulmonary vascular resistance, whereas only inhaled iloprost significantly increased the arterial PO2 (p = 0.01). Compared with inhaled NO, aerosolized iloprost was more effective in reducing pulmonary artery pressure (-8.3 +/- 7.5 mm Hg vs. -4.3 +/- 8.8 mm Hg; p = 0.0001) and the pulmonary vascular resistance (-447 +/- 340 dynes x s x cm(-5) vs. -183 +/- 305 dyne x s x cm(-5); p < 0.0001). Furthermore, aerosolized iloprost caused a significantly greater increase of the cardiac output compared with NO (+0.7 +/- 0.6 liter/min vs. +0.3 +/- 0.4 liter/min; p = 0.0002) and had a more pronounced effect on the mixed-venous oxygen saturation (p = 0.003). CONCLUSIONS: During acute drug testing, aerosolized iloprost was more potent than inhaled NO as a pulmonary vasodilator in PPH at the doses used in this study.

Administration, Inhalation↗
PubMed2000

Lung volume reduction surgery versus conservative treatment in severe emphysema.

Lung volume reduction surgery (LVRS) has been proposed for patients with severe emphysema to improve dyspnoea and pulmonary function. It is unknown, however, whether prognosis and pulmonary function in these patients can be improved compared to conservative treatment. The effect of LVRS and conservative therapy were compared prospectively in 57 patients with emphysema, who fulfilled the standard criteria for LVRS. The patients were divided into two groups according to their own decision. Patients in group 1 (n=29, eight females, mean+/-SEM 58.8+/-1.7 yrs, forced expiratory volume in one second (FEV1) 27.6+/-1.3% of the predicted value) underwent LVRS. Patients in group 2 (n=28, five females, 58.5+/-1.8 yrs, FEV1 30.8+/-1.4% pred) preferred to postpone LVRS. There were no significant differences in lung function between the two groups at baseline; however, there was a tendency towards better functional status in the control group. The control group had a better modified Medical Research Council (MMRC) dyspnea score (3.1+/-0.15 versus 3.5+/-0.1, p<0.04). Model-based comparisons were used to estimate the differences between the two groups over 18 months. Significant improvements were observed in the LVRS group compared to the control group in FEV1, total lung capacity (TLC), Residual volume (RV), MMRC dyspnea score and 6-min walking distance on all follow up visits. The estimated difference in FEV1 was 33% (95% confidence interval 13-58%; p>0.0001), in TLC 12.9% (7.9-18.8%; p>0.0001), in RV 60.9% 32.6-89.2%; p>0.0001), in 6-min walking distance 230 m (138-322 m; p<0.002) and in MMRC dyspnoea score 1.17 (0.79-1.55; p<0.0001). In conclusion, lung volume reduction surgery is more effective than conservative treatment for the improvement of dyspnoea, lung function and exercise capacity in selected patients with severe emphysema.

Adult↗
PubMed2000

[Interferon alpha-2a in the treatment of diffuse thoracic angiomatosis in adulthood--a ase report].

A diffuse angiomatosis affecting thoracal organs is a rare, frequently fatal disorder occurring mainly in childhood. The definite diagnosis is usually made by autopsy. A specific treatment does not exist. In the case report presented here we describe the course of an 37-year old patient presenting initially with dyspnea and hemoptysis. Radiological investigations showed a mass lesion in the anterior superior mediastinum, bihilar masses and a periesophageal mass with soft tissue density and a pericardial effusion. Bilateral interstitial infiltrations were also present. CT-guided mediastinal biopsies and bronchial mucosal biopsies were nonspecific. Open-lung biopsy revealed the diagnosis of an extensive diffuse angiomatosis affecting mediastinum, pericardium and pleura. During the 18-month monotherapy with interferon-alpha 2a the patient showed significant improvements of clinical as well as laboratory and radiological parameters. The presented case confirms the experience of several authors, that the diagnosis of a diffuse thoracal authors can only be made by open lung biopsy or autopsy. The presented case also underlines the possibility of a palliative therapy of aggressive angiomatous diseases with interferon-alpha 2a.

Adult↗
PubMed1998

Cloning of the alphaA-crystallin genes of a blind cave form and the epigean form of Astyanax fasciatus: a comparative analysis of structure, expression and evolutionary conservation.

In the present study we have analyzed the integrity and expression of the alphaA-crystallin gene, that codes for a major structural component of the lens, in a blind cave form of the teleostean fish, Astyanax fasciatus. This is the first alphaA-crystallin gene cloned from a teleostean fish. Sequence comparison of this cave-form gene with its epigean conspecific and with homologs of distantly related taxa has illustrated conservation of regulatory and coding regions. Although no crystallin proteins are produced in the lens of the cave form, and the mRNA of this gene could not be detected by in situ hybridization of different developmental stages, the promoter region of cave-fish alphaA-crystallin is functionally intact. The deduced amino-acid sequence of the alphaA-crystallin gene of the cave form differs from that of its epigean conspecific at only one position (139). This is within an important, small heat-shock protein-related region, HCR2. A comparison of the 5'-flanking regions of the A. fasciatus alphaA-crystallin gene with the chicken homolog revealed the high conservation of lens-specific regulatory sequences and further demonstrates the evolutionary conservation of this gene. 1988 Elsevier Science B.V.

Amino Acid Sequence↗
PubMed1998

Lung volume reduction surgery for severe emphysema.

BACKGROUND: We report mid-term results after 25 consecutive lung volume reduction operations (LVRS) for the treatment of severe dyspnea due to advanced emphysema. METHODS STUDY DESIGN: patients were studied prospectively up to 12 months after surgery. SETTING: preoperative evaluation, surgery and postoperative care took place in our university hospital. PATIENTS: patient selection was based on severe dyspnea and airway obstruction despite optimal medical treatment, lung overinflation and completed rehabilitation programme. PATIENTS with severe hypercarbia (PCO2>50 mmHg) were excluded. Nineteen rehabilitated patients who fulfilled our inclusion criteria but postponed or denied LVRS were followed up clinically. INTERVENTIONS: LVRS was performed bilaterally in 22 patients (median sternotomy) and unilaterally in 3 patients (limited thoracotomy). MEASURES: Outcome was measured by dyspnea evaluation, 6-minute-walking distance and pulmonary function tests. RESULTS: Twelve months postoperatively dyspnea and mobility improved significantly (MRC score from 3.3+/-0.7 to 2.12+/-0.8, 6-min-walk from 251+/-190 to 477+/-189 m). These results were superior compared to the results of the conservatively treated patients. Significant improvement could also be documented in airway obstruction (FEV1 from 960+/-369 to 1438+/-610 ml) and overinflation (TLC from 133+/-14 to 118+/-21% predicted and RV from 280+/-56 to 186+/-59% predicted). CONCLUSIONS: LVRS is an effective and promising treatment option for selected patients with end-stage emphysema and could be offered as an alternative and / or bridge to lung transplantation.

Dyspnea↗
PubMed1997

Comparative analysis of Pax-6 sequence and expression in the eye development of the blind cave fish Astyanax fasciatus and its epigean conspecific.

The Pax-6 gene encodes a transcription factor essential for eye development in a wide range of animal phyla. In order to elucidate a possible role of Pax-6 in the eye regression of a blind cave form of the freshwater fish Astyanax fasciatus (Characidae, Teleostei) we investigated the expression of Pax-6 in eyes and brains of different larval stages by in situ hybridization. Pattern, strength, and time course of Pax-6 expression were not altered in the tissues of the cave form when compared to the epigean form. Pax-6 was even expressed in the highly degenerated eyes of late larval stages of the cave form. Comparative sequence analysis of Pax-6 cDNA clones of both forms of Astyanax fasciatus showed the complete integrity of cave fish Pax-6 mRNA. These results suggest that Pax-6 is not involved in the evolutionary process of eye degeneration in this model system of cave-living fishes. Comparison of the Astyanax Pax-6 cDNA with the other available fish Pax-6 sequence from zebrafish revealed putative fish-specific regions of homology. A stretch of 19 N-terminal amino acids is nearly identical on the nucleotide and amino acid levels in both fish species but not present in all other known Pax-6 sequences.

Amino Acid Sequence↗
PubMed1996

Genetic divergence and speciation in an extremely young species flock in Mexico formed by the genus Cyprinodon (Cyprinodontidae, Teleostei).

The lake Laguna Chichancanab contains one of the evolutionarily youngest species flocks known, composed of five endemic species of the genus Cyprinodon. The presumed sister species Cyprinodon artifrons still exists in marine coastal habitats. Sequences of the mitochondrial control region were obtained for C. artifrons (genes of 17 individuals sequenced) and for all five endemic species (genes of 32 individuals sequenced). While nine different haplotypes were found in C. artifrons, only a single haplotype was shared with the species from the laguna. Four additional haplotypes were found among the endemics. These four were most closely related to that single haplotype shared with C. artifrons. The deprivation in haplotypes among the endemics points to a small founder population or to bottlenecking. The distribution pattern of overlapping haplotypes in four of the five species suggests incomplete lineage sorting or hybridization among them. Complete reproductive isolation is only assumed for one species, C. maya, in which a single and unique haplotype was found.

Animals↗
PubMed1995

Initial mutational steps toward loss of opsin gene function in cavefish.

The river-dwelling fishes of Astyanax fasciatus and their derivatives from Pachon and Micos caves in Mexico were collected. By comparing red (r007) and green (g103) opsin gene sequences from the three populations, we found a high frequency of C-->T changes in r007 and g103 of the eyed Micos fishes presumably due to spontaneous cytosine methylation or enzymatic deamination of the CG dinucleotide, and a deletion of 12 consecutive nucleotides in g101 of the blind Pachon fishes. Thus, high rates of nucleotide substitution and C-->T transitions, usually found for pseudogenes, may occur even before they become nonfunctional.

Animals↗
PubMed1995

[Death or uncertain cause].

The unclear case of death usually occurs suddenly and unexpectedly, but can mostly be attributed to a underlying disease which was unknown during the life-time of the patient. A reduction of mortality might be achieved by improved preventive measures and early treatment. During the last years, the sleeping apnea syndrome as an example turned out to be a considerable risk factor for cardiovascular diseases and accidents. Nevertheless, very many patients exist with an unrecognized sleeping apnea syndrome and are in urgent need of therapy. At first, unclear cases of death in the area of internal medicine can mostly be solved by an autopsy. Autopsy results are demonstrating that only one of three pulmonary embolism has been recognized clinically. The correct diagnosis for an unexpected death in the area of internal medicine could be almost ever found by a more careful differential diagnosis; only a few cases of death remain unclear after optimal diagnostics. At first, one has to think of a pulmonary embolism, cardiac arrhythmias or myocardial ischemia when a sudden death has occurred. Additionally, a pneumothorax, an alimentary bolus or an asthma attack may cause death unexpectedly. Metabolic dysfunctions, poisoning or a ruptured aortic aneurysm are often not recognized as the cause of death if it is not especially looked for.

Asthma↗
PubMed1992

Bioassay of a tracheal smooth muscle-constricting factor released by respiratory epithelial cells.

Epithelium-derived factors of unknown identity have been proposed to modulate airway smooth muscle tone. We developed a novel sensitive bioassay system that allows serial perfusion of cultured respiratory epithelial cells and guinea pig trachea (GPT). GPT responses were assessed as diameter changes by computerized video microscopy (resolution, 15 microns). A permanent hamster lung epithelial cell line was grown on microcarrier beads and perfused in a cell column. When the outflow tubing from the epithelial cell column was connected to the inflow cannula, the detector GPT contracted, reaching 28 +/- 6% of the maximum methacholine (100 microM)-induced contraction (n = 12, P less than 0.001). Perfusion of the cell column with diclofenac (10 microM) or lysin-mono-acetylsalicylic acid (100 microM) abolished the GPT contraction, whereas selective perfusion of the detector GPT with either agent did not block the contraction. Analysis of the effluent of the epithelial cell column demonstrated a significant basal release of prostaglandins F2 alpha and E2 (PGF2 alpha and PGE2) and 6-ketoprostaglandin F1 alpha, whereas only marginal amounts of thromboxane B2 were detected. When given exogenously, PGF2 alpha, PGE2, PGI2, and U-46619 all contracted the GPT. It is concluded that lung epithelial cells can contract GPT by releasing a transferable factor. This factor is likely to be a constrictor cyclooxygenase product that is not produced in epithelium-denuded GPT.

Animals↗
PubMed1991

Burst suppression EEG with baclofen overdose.

The article reports the case history of a patient with baclofen intoxication and burst suppression activity in the EEG several hours after baclofen ingestion. With symptomatic treatment the patient recovered within 5 days and the EEG became normal, again.

Adult↗
PubMed1990

Effects of a PAF-antagonist (BN 52063) on bronchoconstriction and platelet activation during exercise induced asthma.

1. The effects of a specific PAF acether antagonist (BN 52063) on the response to isocapnic hyperventilation with dry cold air (ISH study) and exercise (EIA study) were assessed in a single dose and short term treatment study in 10 patients with exercise induced asthma. 2. ISH challenge was performed twice within 1 h after administration of either placebo, 240 mg BN 52063 p.o. or inhalation of 2.4 mg BN 52063. Hyperventilation increased Raw from 0.30 +/- 0.02 to 0.89 kPa s l-1 (P less than 0.001) after the first challenge and from 0.28 +/- 0.04 to 0.84 +/- 0.06 kPa s l-1 (P less than 0.001) after the second challenge. Oral pretreatment with BN 52063 did not result in a reduction of bronchoconstriction during both challenges. A significant increase of Raw was noted immediately after inhalation of BN 52063. An inhibition of PAF induced platelet aggregation (by a factor of 2) occurred after oral administration of BN 52063 after both ISH challenges (P less than 0.05). No significant inhibition of PAF induced platelet aggregation was seen after inhalation of BN 52063. At concentrations up to 30 microM in vitro, BN 52063 inhibited PAF induced platelet aggregation in a dose dependent manner. The IC50 of BN 52063 against the aggregating effect of 1 microM PAF was 7.0 +/- 2.1 microM. 3. In the EIA study the patients were challenged on the third day of treatment with either placebo or 240 mg BN 52063 p.o. or 5 mg BN 52063 by inhalation. Peak expiratory flow rates (PEFR) fell by 155 +/- 37 1 min-1 after exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗
PubMed1990

[The topography of the abdominal organs of Monodelphis domestica (Marsupialia)].

30 adult animals (14 females, 16 males) were studied macroscopically. The main findings are as follows: 1. The intestine is without striking macroscopic features that characterize the different parts of it. A variation of position of ileum, cecum, and colon, respectively, is due to the length of their mesenteries. 2. In adult males, the intestines are displaced from their position in the caudal part of the abdomen by the urethra (the urethral diameter is even wider than that of the gut, because the wall contains masses of prostatic glandular tissue). 3. The liver is clearly divided into lobes, however, there is no notch between the quadrate lobe and the left medial lobe. The falciform ligament is regarded as the border-line between these lobes, while the gall bladder separates the quadrate lobe from the right medial lobe. 4. The spleen lies almost entirely caudal to the costal arch. It extends dorsally between the stomach and the left kidney. Along the body wall, it reaches the ventral median line and shows even a slight orientation towards the xiphoid cartilage. 5. The greater omentum may extend to the cranial end to the urinary bladder. It is extremely thin and therefore hardly visible. 6. In females, subperitoneal fat may extend from the caudo-dorsal body wall along the lateral walls down to ventral regions, in some cases even occupying a considerable part of the caudo-ventral abdomen.

Animals↗