The evolution of the lower Metazoa: evidence from the phenotype.
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Animals↗
Biomedical subjects
R Rieger
Publications and source records attributed to R Rieger.
[Clinical application of biopsy of the sentinel lymph node in breast carcinoma].
Sentinel lymph node (SN) biopsy in primary breast cancer seems to be an alternative to complete axillary lymph node dissection for evaluation of the axillary lymph node status in selected patients. Following evaluation of the technique of SN biopsy, we applied SN biopsy clinically to 23 selected patients. A lymphoscintigraphy was performed preoperatively to evaluate lymphatic drainage. The SN was identified in the operating room by use of a hand-held gamma camera and a blue vital dye. The SN was found in all 23 patients. In 17/23 the SN was tumor free and no axillary dissection was performed; 6/23 showed a positive SN and complete axillary dissection was done. Intraoperative lymphatic mapping and SN biopsy may be the treatment of choice for evaluation of axillary node status in selected patients, for it combines accurate nodal staging and low morbidity.
Aged↗
A diagnostic score to predict the difficulty of a laparoscopic cholecystectomy from preoperative variables.
BACKGROUND: Modified logistic regression analysis of 24 variables in 300 patients undergoing laparoscopic cholecystectomy found the following parameters independently predictive for a difficult operation: right upper quadrant pain (p < 0.01), rigidity in right upper abdomen (p < 0.01), previous upper abdominal surgery (p < 0.01), biliary colic within the last 3 weeks (p < 0.05), white blood cell count > 10 x 10(9)/l (p < 0.05), thickening of the gallbladder wall (p < 0.05), hydroptic gallbladder (p < 0.05), pericholecystic fluid (p < 0.01), shrunken gallbladder (p < 0.01), and no filling of the gallbladder in preoperative intravenous cholangiography (p < 0.05). METHODS: Based on these variables a diagnostic model was developed to predict the difficulty of a laparoscopic cholecystectomy, with scores ranging from 0 (ideal case) to IV (conversion to open cholecystectomy expected) prior to surgery. RESULTS: When the reliability of our model was examined in a second study in 340 consecutive patients undergoing laparoscopic cholecystectomy 80% of the patients were predicted correctly. CONCLUSIONS: Our model should help to select patients for either laparoscopic or open cholecystectomy based on the expected difficulties and the experience of the surgeon.
Acute Disease↗
Thoracoscopic bleb resection selectively combined with pleurectomy for complicated spontaneous pneumothorax.
OBJECTIVE: To evaluate the short and long term results of video-assisted thoracoscopic surgery for complicated pneumothorax. DESIGN: Retrospective study. SETTING: General hospital, Linz, Austria. SUBJECTS: 76 consecutive patients with complicated pneumothorax. INTERVENTIONS: 57 patients with primary and 19 with secondary spontaneous pneumothorax underwent video-assisted thoracoscopic surgery. Depending on the findings at thoracoscopy, patients were allocated to have stapled bleb resection (n=29), multiple bleb resection combined with apical pleurectomy (n=40), or apical segmental resection combined with apical pleurectomy (no visible disease on the lung surface, n=7). MAIN OUTCOME MEASURES: Efficacy, morbidity, mortality, and late recurrence rate. RESULTS: No conversions to open thoracotomy were necessary and early lung reexpansion was achieved in all but one patient (99%). There was one postoperative death (1%) and morbidity was 7%, including one persistent air leak and one early recurrence, both of which required thoracotomy. All postoperative complications developed in patients with spontaneous pneumothorax secondary to diffuse bullous emphysema. At a median follow up of 34 months there were 4 ipsilateral pneumothorax recurrences (5%), two of which developed after bleb resection combined with pleurectomy and two after bleb resection alone. CONCLUSION: Video-assisted thoracoscopic surgery was safe and effective for the treatment of complicated spontaneous pneumothorax. It is our procedure of choice for complicated primary spontaneous pneumothorax and is a valuable alternative to open thoracotomy for patients with secondary spontaneous pneumothorax.
Adult↗
Removal of O6-methylguanine from plant DNA in vivo is accelerated under conditions of clastogenic adaptation.
Previously it was shown that the clastogenic efficiency of high doses of alkylating agents in plant root meristems can be reduced significantly by conditioning pretreatment with either a low dose of the same agents, a sublethal heat shock, or heavy metal salts. The molecular mechanisms responsible for these protective effects are still unclear. Here we report on the quantification of O6-methylguanine [O6-MeG] by immuno-slot-blot analysis in DNA of root tip meristems of field bean (Vicia faba) seedlings under conditions of clastogenic adaptation. When root tips were pretreated with a low, conditioning dose of N-methyl-N-nitrosourea (MNU, 10(-4) M, 1 hour) 2 hours before exposure to a high dose of the same clastogen (10(-3) M, 1 hour), the frequency of chromatid aberrations was reduced by more than 50% at a recovery time of 1 B hours, as compared to treatment with the high dose alone. The same was observed when conditioning pretreatment was by a sublethal heat shock [10 minutes, 40 degrees C] or a heavy metal salt (Cd(NO)3, 10(-7) M, 1 hour). The frequency of O6-MeG immediately after exposure to a conditioning and a subsequent challenge treatment was reduced by 43% as compared to treatment with only the high dose. At a recovery time of 18 hours the corresponding frequency of adducts was reduced by 68.3% (related to the initial level) after treatment with the high dose alone, and by 81.3% under adaptive conditions. Sublethal heat shock or heavy metal salt used as conditioning pretreatments also resulted in a decrease of adducts immediately after treatment with the challenge dose. From these data and from prevention of the effects by pretreatment with cycloheximide or O6-benzylguanine we conclude that under conditions of clastogenic adaptation O6-MeG is more efficiently removed from the DNA, presumably by induction of an alkyl acceptor protein such as O6-methylguanine-DNA methyltransferase [MGMT]. This could explain the observed protective effects (clastogenic adaptation.
Adaptation, Physiological↗
The human 37-kDa laminin receptor precursor interacts with the prion protein in eukaryotic cells.
Prions are thought to consist of infectious proteins that cause transmissible spongiform encephalopathies. According to overwhelming evidence, the pathogenic prion protein PrPSc converts its host encoded isoform PrPC into insoluble aggregates of PrPSc, concomitant with pathological modifications (for review, see refs. 1-3). Although the physiological role of PrPC is poorly understood, studies with PrP knockout mice demonstrated that PrPC is required for the development of prion diseases. Using the yeast two-hybrid technology in Saccharomyces cerevisiae, we identified the 37-kDa laminin receptor precursor (LRP) as interacting with the cellular prion protein PrPC. Mapping analysis of the LRP-PrP interaction site in S. cerevisiae revealed that PrP and laminin share the same binding domain (amino acids 161 to 180) on LRP. The LRP-PrP interaction was confirmed in vivo in insect (Sf9) and mammalian cells (COS-7). The LRP level was increased in scrapie-infected murine N2a cells and in brain and spleen of scrapie-infected mice. In contrast, the LRP concentration was not significantly altered in these organs from mice infected with the bovine spongiform encephalopathic agent (BSE), which have a lower PrPSc accumulation. LRP levels, however, were dramatically increased in brain and pancreas, slightly increased in the spleen and not altered in the liver of crapie-infected hamsters. These data show that enhanced LRP concentrations are correlated with PrPSc accumulation in organs from mice and hamsters. The laminin receptor precursor, which is highly conserved among mammals and is located on the cell surface, may act as a receptor or co-receptor for the prion protein on mammalian cells.
Actins↗
Formation and repair of O6-methylguanine in recombination hot spots of plant chromosomes.
Mutagen-induced chromatid aberrations are not randomly distributed along the metaphase chromosomes. In the field bean (Vicia faba), defined late-replicating and transcriptionally inactive heterochromatic regions are preferentially involved. After exposure to the alkylating agent N-methyl-N-nitrosourea (MNU) (10(-3) M, 1 hour), 70% of all aberrations are clustered within 6 segments containing tandemly repeated FokI elements of 59 bp, which comprise approximately 10% of the genome. Using immuno-slot-blot analyses, we have studied the frequency of O6-methylguanine (O6-MeG), a mutagenic lesion important for aberration induction, in total genomic DNA as well as in FokI sequences of the field bean after exposure to MNU. In either case, similar numbers of adducts per nucleotide were found immediately after treatment as well as after 18 hours of recovery, when most adducts were removed and significant amounts of chromatid aberrations were detectable. Peculiarities of long FokI element arrays (e.g., formation of specific tertiary structures), resulting in error-prone recombination repair, rather than preferential formation or delayed repair of O6-MeG are apparently responsible for aberration clustering in these hot spot regions.
Alkylating Agents↗
[Video-assisted thoracoscopy in diagnosis and therapy of intrathoracic diseases].
Video-assisted thoracoscopy has become an important adjunct to traditional thoracic surgical techniques for the diagnosis and therapy of numerous intrathoracic diseases. It has developed to the procedure of choice for patients with spontaneous pneumothorax, indeterminate peripheral lung nodule, diffuse lung disease, pleural disease and effusion and is a valuable alternative to traditional thoracotomy for various indications like the resection of benign intrathoracic tumors and cysts. Although video-assisted thoracoscopy is not recommended for curative therapy of malignancies, it can be useful for the diagnosis, staging and palliation of malignant disease. Video-assisted thoracoscopy should be performed only by surgeons with sufficient experience in thoracic surgery in institutions where adequate prerequisites are available. The clinical impact of video-assisted thoracoscopy is documented by the fact that in centers approximately 20 to 30% of all thoracic surgical procedures currently are performed with this new technique.
Endoscopes↗
Recombinant prion protein rPrP27-30 from Syrian golden hamster reveals proteinase K sensitivity.
PrP27-30 represents the protease-resistant core of the prion protein and was found to be the main component in Scrapie prion preparations. Recombinant (r) PrP27-30 corresponding to aa 90-231 from the Syrian golden hamster prion protein was expressed as a fusion with GST in E. coli and secreted from insect cells infected with recombinant baculoviruses, GST::rPrP27-30 isolated from either system was purified to homogenity by glutathione-Sepharose chromatography. rPrP27-30 from both systems was generated by direct cleavage of GST::rPrP27-30 in the presence of thrombin revealing a molecular weight of 17 kDa. GST::rPrP27-30 as well as the authentic protein rPrP27-30 were identified by immunoblotting employing a polyclonal antibody directed against a peptide corresponding to aa 95-110 of the Syrian golden hamster prion protein. In contrast to scrapie prior PrP27-30, the recombinant proteins GST::rPrP27-30 and rPrP27-30 were both sensitive towards proteinase K, suggesting that the molecules lack infectivity.
Animals↗
Prospective randomized trial comparing postoperative pain and return to physical activity after transabdominal preperitoneal, total preperitoneal or Shouldice technique for inguinal hernia repair.
In a prospective randomized study postoperative pain, analgesic consumption, return to physical activity and work, cosmetic result and experience with the type of operation were assessed in 86 patients undergoing inguinal hernia repair by means of either the Shouldice technique (n = 34), the laparoscopic transabdominal preperitoneal (TAPP) (n = 28) or total preperitoneal (TPP) (n = 24) repair. Patients having TAPP repair had decreased visual analogue scale scores for pain on the day of operation compared with those undergoing TPP and Shouldice repair (4.8 versus 6.5 and 6.2 respectively, P = 0.02) and on the first postoperative day compared with TPP (4.0 versus 6.0, P = 0.01). There was no difference between the three groups for days 2, 3, 4, 5 and 30 after operation. Patient satisfaction with the operation, analgesic consumption, return to physical activity such as walking, driving, climbing stairs, running, bicycling and sexual intercourse, as well as return to work, was comparable in the three groups. There was a better cosmetic result after TAPP and TPP repair. This study failed to demonstrate significant benefits from laparoscopic hernia repair over the Shouldice technique.
Activities of Daily Living↗
Metabolic responses after laparoscopic or open hernia repair.
BACKGROUND: The purpose of a prospective randomized study was to compare the surgical trauma in patients undergoing laparoscopic or open hernia repair. METHODS: Postoperative pain, analgesic consumption, and metabolic response to surgery were assessed in 30 patients undergoing laparoscopic (group 1; n = 15) or open (group II; n = 15; Shouldice repair) unilateral inguinal hernia repair. Both groups were comparable with respect to age, sex, and type and size of inguinal hernia. RESULTS: Postoperative visual analogue scales (VAS) for pain were reduced on mobilization for patients of group I with a significant difference (P = 0.02) on the operative day, whereas pain scores at rest and analgesic requirements were similar for both groups. No differences between groups I and II were found in postoperative levels of interleukin-1, interleukin-6, tumor necrosis factor alpha, C-reactive protein, fibrinogen, transferrin, alpha-1-antitrypsin, and white blood cells. Postoperative polymorphonuclear (PMN) elastase concentrations remained within normal range in group II but showed a significant increase in patients operated laparoscopically for postoperative days 1 and 2. CONCLUSIONS: No major surgical trauma was found after herniorraphy compared to open hernia repair.
Acute-Phase Proteins↗
Videothoracoscopy for the management of mediastinal mass lesions.
BACKGROUND: The indications for video-assisted thoracoscopy have steadily expanded during recent years and include now the management of various mediastinal disorders. METHODS: Until now we have used videothoracoscopy for the diagnosis or treatment of mediastinal mass lesions in 28 patients. The indication for the procedure was bilateral or unilateral mediastinal adenopathy in 16, a suspected malignant anterior mediastinal mass lesion in six, and a presumable benign tumor of the posterior or anterior mediastinum in six patients. RESULTS: Video-assisted thoracoscopy provided an accurate tissue diagnosis in all patients with adenopathy and in all but one patient with a malignant mass lesion of the anterior mediastinum. It further allowed complete excision of all benign tumors of the anterior or posterior mediastinum. There were no intra- or postoperative complications, but conversion to open thoracotomy was necessary in one patient. CONCLUSIONS: Video-assisted thoracoscopy is a valuable adjunct to traditional surgical techniques for the diagnosis of malignant mediastinal disease and may overcome some of the limitations of mediastinoscopy and mediastinotomy. In the future, it may become the procedure of choice for the resection of small benign tumors of the anterior or posterior mediastinum.
Adult↗
Mechanism, management, and prevention of laparoscopic bowel injuries.
BACKGROUND: Inadvertent injury to the bowel is a rare but potentially fatal complication of laparoscopy. Such injury often goes unrecognized at the time of the procedure and only later is manifest by high morbidity and mortality. METHODS: We reviewed the mechanism and management of 10 instances of bowel injury known to have been encountered in a series of 4672 laparoscopic procedures performed at our hospital over the past 5 years. RESULTS: The usual causes of injury to the bowel wall were thermal burns, sharp dissection, and needle punctures. Six of the injuries were readily evident and treated immediately; four were unrecognized until 2 to 14 days after the procedure. One patient died of multiple organ failure on the third day after laparoscopy. Operative management in nine cases required simple closure or segmental resection. A high index of suspicion and vigilant physical examination were the keys to early recognition of bowel injury; laboratory and radiographic findings were nonspecific. CONCLUSIONS: Suspected bowel injury following laparoscopy mandates early laparotomy to avoid life-threatening complications.
Adult↗
Prion protein PrPc interacts with molecular chaperones of the Hsp60 family.
Prions mediate the pathogenesis of certain neurodegenerative diseases, including bovine spongiform encephalopathy in cattle and Creutzfeldt-Jakob disease in humans. The prion particle consists mainly, if not entirely, of PrPSc, a posttranslationally modified isoform of the cellular host-encoded prion protein (PrPc). It has been suggested that additional cellular factors might be involved in the physiological function of PrPc and in the propagation of PrPSc. Here we employ a Saccharomyces cerevisiae two-hybrid screen to search for proteins which interact specifically with the Syrian golden hamster prion protein. Screening of a HeLa cDNA library identified heat shock protein 60 (Hsp60), a cellular chaperone as a major interactor for PrPc. The specificity of the interaction was confirmed in vitro for the recombinant proteins PrPc23-231 and rPrP27-30 fused to glutathione S-transferase with recombinant human Hsp60 as well as the bacterial GroEL. The interaction site for recombinant Hsp60 and GroEL proteins was mapped between amino acids 180 and 210 of the prion protein by screening with a set of recombinant PrPc fragments. The binding of Hsp60 and GroEL occurs within a region which contains parts of the putative alpha-helical domains H3 and H4 of the prion protein.
Animals↗
Resection of paravertebral neurofibroma by video-assisted thoracoscopy.
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Adult↗
Gallbladder remnant after laparoscopic cholecystectomy.
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Acute Disease↗
Yield of prospective, noninvasive evaluation of the common bile duct combined with selective ERCP/sphincterotomy in 1390 consecutive laparoscopic cholecystectomy patients.
The role of noninvasive evaluation of the common bile duct combined with selective preoperative endoscopic retrograde cholangiography and sphincterotomy was prospectively evaluated in 1390 consecutive patients subjected to laparoscopic cholecystectomy. Preoperative common bile duct testing included liver chemistries, transcutaneous ultrasonography, and intravenous cholangiography. When indicated by various sets of abnormal studies, prelaparoscopic endoscopic retrograde cholangiography was attempted in 129 patients (9.3%) and successfully accomplished in 122 (94.6%). Seventy-six patients (62.3%) had duct stones or a papillary stenosis, and 73 of them (96%) were treated successfully by endoscopic duct clearance and subsequent laparoscopic cholecystectomy. No deaths occurred, and the morbidity rate was 6.2% (8/129), including 2 cases of pancreatitis and 1 case of a retained duct stone after sphincterotomy. Predicting the presence of common duct pathology was 60% accurate when based on abnormal laboratory test results alone, 69% when based on abnormal laboratory test results and concomitant radiologic abnormalities, and 42% when based on radiologic criteria alone (p < .05). We conclude that patients with altered serum liver chemistries with or without concomitant positive radiologic criteria should undergo endoscopic cholangiography before laparoscopic cholecystectomy. However, in patients with radiologic duct dilatation as the sole indicator for duct stones, the frequency of normal findings in endoscopic examinations is high. This latter group is probably better managed with intraoperative cholangiography and postlaparoscopic sphincterotomy if needed.
Case-Control Studies↗
Whipple procedure with staple closure of the pancreas.
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Adult↗