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R Rieger

Publications and source records attributed to R Rieger.

At least 55 records · Page 3Linked to original sources
PubMed1995

[CT-guided wire marking of peripheral pulmonary coin lesions--value for thoracoscopic resection].

Thoracoscopic identification of small and deep seated peripheral lung lesions may be difficult. To facilitate resection in such cases, a technique of CT-guided transthoracic hook wire localisation has been developed. We used this technique for localization of 12 peripheral lung lesions in 11 patients. In all cases the hook wire was correctly placed within or just beside the nodule and subsequent thoracoscopic resection was fast and easily accomplished in all. The described localization technique has a low complication rate and can be recommended for patients with small peripheral lung nodules subjected to thoracoscopic surgery.

Adenocarcinoma↗
PubMed1995

[Pancreas resection with the surgical stapler. Technique and results].

In a consecutive series of 42 pancreatoduodenectomies and 17 distal pancreatectomies we evaluated the applicability of the stapler TA-55 for transecting the pancreas parenchyma. In 90% of Whipple's operations and in 88% of distal pancreatectomies the transection of the pancreas was successfully accomplished by using the TA-55. The two rows of steel staples lead to a uniform closure of the pancreatic tissue and thus provided an excellent precondition for pancreatic stump healing and creation of a pancreaticojejunal anastomosis. Pancreatic fistulas occurred in 3 cases (5%) and were all successfully treated conservatively. Summarizing our experience, the stapler TA-55 can be recommended particularly for the transection of normal and fragile pancreatic tissue.

Adult↗
PubMed1994

Sequence organization and the mechanism of interstitial deletion clustering in a plant genome (Vicia faba).

Intercalary deletions and duplication-deletions are types of chromatid aberrations typical of the aberration spectrum observed in the first mitosis of plant cells after mutagen treatment. They are the results of error-prone recombination repair and arise when reunion is not prevented by inhibition of DNA synthesis. Both types of aberrations are nearly exclusively located in chromosome regions composed of tandemly arranged highly repetitive DNA sequences (e.g. FokI elements). The data discussed in the present paper make it possible to arrive at a simple mechanistic interpretation of the origin of these aberration types.

Chromatids↗
PubMed1994

Sister-chromatid exchanges in Picea abies--a test for genotoxicity in forest trees.

A genotoxicity test, based on the evaluation of sister-chromatid exchange frequencies, has been developed for the spruce fir. The basic frequency was 36.9 SCEs/cell. Mitomycin C treatment (MMC, 5 x 10(-6) M, 0.5 h) doubled the 'spontaneous' SCE frequency, maleic hydrazide treatment (MH, 5 x 10(-4) M, 0.5 h) increased it nearly 7-fold. This corresponds to data obtained previously for Vicia faba. Chromatid-type aberrations were induced by the same mutagens (MH, 5 x 10(-4) M, 0.5 h; MMC 2 x 10(-5) M, 1 h) or by triethylenemelamine (TEN, 2 x 10(-4) M, 0.5 h). MH treatment resulted in aberration yields comparable to those observed in Vicia faba, MMC and TEM were less efficient aberration inducers in P. abies. While SCEs may be counted for single chromosomes, for reliable evaluation of chromatid aberrations large numbers of complete and well spread metaphases have to be inspected.

Air Pollution↗
PubMed1994

Diagnostic laparoscopy: a survey of 92 patients.

From January 1991 to June 1993 the authors performed 92 diagnostic laparoscopies when physical examination, laboratory tests, and noninvasive imaging techniques failed to provide accurate diagnoses. Thirty-three patients (36%) underwent laparoscopy to ensure or exclude diagnosis in suspected intra-abdominal malignancy or to assess the operability in the cases of known cancer; 31 patients (34%) were evaluated for chronic abdominal pain; 15 patients (16%) were evaluated for acute abdominal pain; 9 trauma patients (10%) were evaluated to exclude or confirm penetration of the peritoneum or laceration of intra-abdominal organs; and 4 patients (4%) were operated on for miscellaneous conditions. Of the 92 patients, laparoscopy led to diagnosis in 80 patients (87%), a laparotomy was avoided in 78 patients (85%), and operative treatment was done laparoscopically in 65 patients (71%). Diagnostic laparoscopy will not replace laparotomy in every instance. However, in selected groups of patients, it may be used to yield diagnosis and help to avoid unnecessary laparotomy.

Abdomen↗
PubMed1994

[Thoracoscopic therapy of iatrogenic hemothorax].

Video-assisted thoracoscopy is an innovative technique which now allows the surgeon to approach various intrathoracic pathologic conditions without thoracotomy. In a 20-year-old male with pneumothorax urgent surgical intervention was necessary because of severe hemothorax following chest tube placement. The successful management of this patient by video-assisted thoracoscopy is presented.

Adult↗
PubMed1993

[Laparoscopic hernia repair].

From January 1992 to February 1993 a total of 361 inguinal hernia repairs were performed in our unit. We routinely performed the Shouldice repair. In 60 patients, 46 men and 14 women, 19-82 year old, we closed the inguinal defect with a patch, performing a "tension-free" repair by a laparoscopic technique. In 26 patients we found a left-sided hernia, in 21 patients a right-sided, and in 13 bilateral hernias. We found 29 direct hernias, 26 indirect hernias and 18 combined hernias. There were no intraoperative complications. Postoperatively, 1 patient suffered from epididymitis, and 5 patients reported disturbed sensibility of the skin at the medial proximal thigh for some weeks. One patient had an inguinal seroma postoperatively. In this patient we had not removed the hernia sac. There was no recurrence. Long time results are not available until now.

Adult↗
PubMed1993

Inhibition of protein synthesis by cycloheximide does not prevent adaptive responses triggered by heavy metal salts in Vicia faba.

Copper sulfate, lead nitrate, and cadmium nitrate conditioning treatments of Vicia faba root tip meristem cells result in adaptive responses to triethylenemelamine (TEM)- and maleic hydrazide (MH)-induced genotoxic effects, i.e., they significantly reduce the yield of metaphases with chromatid aberrations. Contrary to adaptive responses triggered by low clastogen concentrations or heat shock, protective effects induced by heavy metals cannot be prevented by inhibition of protein synthesis and last for a much longer time span (up to at least 48 h). These and other data support the conclusion that the cells can react to the impact of external factors by various inducible functions which eventually protect their DNA from damage.

Adaptation, Physiological↗
PubMed1993

Combined application of MH and TEM for conditioning treatment simultaneously triggers two protective functions against induction of chromatid aberrations in Vicia faba root tip meristem cells.

Conditioning pre-exposure of Vicia faba root tip meristem cells to triethylenemelamine (TEM) does not trigger an adaptive response to maleic hydrazide (MH) and vice versa. Since TEM conditioning treatment can induce protective effects (as evident from the yield of metaphases with chromatid aberrations) against TEM challenging treatment and MH conditioning can trigger an adaptive response to MH challenging treatment, two different protective functions are apparently triggered in dependence on the agent used for conditioning pre-exposure. When a mixture of TEM and MH is being used for conditioning treatment, adaptive responses to both TEM and MH can simultaneously be induced and significantly reduce the yield of metaphases with chromatid aberrations observed after challenge treatment with TEM or MH.

Adaptation, Physiological↗
PubMed1993

Thoracoscopic wedge resection of peripheral lung lesions.

The increasing experience with minimally invasive surgery and advances in endoscopic equipment have expanded the role of thoracoscopy to include thoracoscopic pulmonary resections. In 11 patients we have evaluated the technical feasibility of thoracoscopic wedge resection of single peripheral lung lesions. In 8 patients the lesion could be exactly identified by thoracoscopy and be effectively resected using an automatic endoscopic stapler. All lesions were located within the outer third of the lung parenchyma with a maximum distance of 1.4 cm between lesion and visceral pleura. Mean diameter of the nodules was 1.9 cm and ranged from 1.0 to 4.1 cm. Histological analysis revealed completely excised tuberculomas in 4, carcinomas in 2, hamartoma in 1, and localised fibrosis in one patient. In 3 patients the thoracoscopic approach was unsuccessful because of difficulty in identifying the lesion or impossibility of achieving a reliable assessment of the intraparenchymal extension of the tumor. In conclusion, thoracoscopic wedge resection is helpful for the diagnostic and therapeutic management of peripheral lung lesions in carefully selected patients. Continued experience is necessary to be able to establish reliable criteria to assess which types of lung lesion can be excised safely and effectively by videothoracoscopy.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1993

[Laparoscopic cholecystectomy--advantages and disadvantages].

From march 1990 to february 1992 we performed 600 laparoscopic cholecystectomies. In 18 cases we had to change to a laparotomy because of intraoperative problems, in 3 cases we had to laparotomise patients because of postoperative complications. 9 patients (1.5%) had a wound infection. In two prospective studies we could prove that patients after laparoscopic cholecystectomy have less pain and are in a better respiratory condition than after open cholecystectomy.

Adolescent↗
PubMed1992

Drosophila retinal degeneration C (rdgC) encodes a novel serine/threonine protein phosphatase.

The Drosophila retinal degeneration C (rdgC) gene is required to prevent light-induced retinal degeneration. Molecular analysis shows that the rdgC transcription unit encodes a novel serine/threonine protein phosphatase. Amino acids 153-393 define a domain that has 30% identity with the catalytic domains of types 1, 2A, and 2B serine/threonine protein phosphatases. A putative regulatory domain is appended that contains multiple potential Ca(2+)-binding sites or "EF hand motifs." Thus, the analysis suggests that the rdgC protein is a novel type of serine/threonine protein phosphatase that is directly regulated by Ca2+. rdgC is expressed in the visual systems of the fly, as well as in the mushroom bodies of the central brain.

Amino Acid Sequence↗
PubMed1992

Low temperature between conditioning and challenge treatment prevents the 'adaptive response' of Vicia faba root tip meristem cells.

When the temperature during intertreatment time (2 h) between conditioning and challenge treatment of Vicia faba root tip meristems with either triethylenemelamine or maleic hydrazide was reduced from 24 degrees C to 12 degrees C no adaptive response occurred any more. The yield of metaphases with chromatid aberrations under these circumstances was similar to that observed after challenge treatment alone, i.e., no reduction occurred. This indicates that the metabolic state of the cells is of critical importance for the presence or absence of adaptive responses.

Adaptation, Physiological↗
PubMed1992

[Laparoscopic surgery--the revolution in gallstone treatment].

The treatment of gallbladder disease is revolutionized by laparoscopic cholecystectomy (LCHE). Less pain postoperatively, earlier mobilization and a fascinating cosmetic result as well as a definitive cure of the disease have led to a fast acceptance by patients and doctors. From March 1990 to March 1991 we have performed 250 LCHE. Only 5 times we had to switch to the conventional procedure. 5 complications (1 lesion of the common bile duct, 2 biliary effusion, 1 abscess formation, 1 bleeding) were treated by laparotomy without further morbidity or lethality. Our rate of gallbladders operated by laparoscopy has increased from 35% in 1990 to 75% in 1991.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1992

[Technique of recurrent laryngeal nerve exposure within the scope of interventions of the thyroid gland].

In anatomical preparations performed during autopsy we developed a well-defined approach for the identification of the recurrent laryngeal nerve during surgery on the thyroid gland. The principle of this concept is to visualize the nerve near the branching of the inferior thyroid artery, where it shows a 30 degree angle to the trachea in a direction running from caudal lateral to cranial medial and lies in front of, behind, or between the branches of the artery. This preparation mode has been prospectively performed in 100 patients undergoing thyroid surgery. In 159 (= 97.6%) sides of the neck out of 163 we identified the nerve at the typical site. The topographical relation of the recurrent nerve to the inferior thyroid artery revealed the following differences for the right and left side of the neck: On the right side the nerve was found to be behind in 48%, in front in 33% and between the branches of the artery in 15% of cases. In contrast, on the left side the nerve was found to be dorsal in 53%, ventral in 23% and between the branches in 23%. Of 163 nerves at risk we observed primary nerve palsy in 2 cases (1.2%), and a definitive palsy rate of 0.6% at the 3-month follow-up. In conclusion, we recommend the described approach for the identification of the recurrent laryngeal nerve during thyroid surgery whenever complete mobilisation of the thyroid lobe (e.g. thyroidectomy, lobectomy, resection of retrotracheal adenomas) is necessary.

Female↗
PubMed1991

Determination of glycyrrhetinic acid in human plasma by high-performance liquid chromatography.

A high-performance liquid chromatographic (HPLC) method has been developed for measuring 18 beta-glycyrrhetinic acid (GRA) in human plasma in the range of 0.1-3 micrograms/ml. The acetate ester of GRA is added to the plasma as an internal standard, plasma proteins are denatured with urea to release GRA, and the GRA and the internal standard are extracted in an ion-pairing solid-phase extraction process. An isocratic, reversed-phase HPLC separation is used, followed by ultraviolet absorbance detection at 248 nm. The results from the analysis of five GRA-fortified plasma pools show a mean relative standard deviation of 7% and are accurate to within 10%. With evaporative concentration of the extract, the limit of detection for GRA in plasma is approximately 10 ng/ml.

Chromatography, High Pressure Liquid↗