[CT-guided marking of lung lesions before minimally invasive operation]

Video-assisted thoracoscopic surgery (VATS) is an established method for resection of suspicious pulmonary lesions. However, there are problems to detect small subpleural lesions. A procedure for localization of such lesions will be demonstrated. Since may 2000 our experience includes 5 patients (4m, 1f) suffering from solitary pulmonary lesions. In preparation of VATS a CT-guided marking was carried out using both a lasermarker system as well as a special marker system for lung lesions. All 5 procedures were successful. With the laser system the pulmonary nodule was exactly marked and the special wire was placed without any complications. Consequently, the pulmonary nodule was fixed. During video-assisted wedge resection the nodule can be tracted outside. Operating time was reduced in comparison to time consuming search of unmarked lesions. The combined application of CT-guided marking, transthoracic fixation of pulmonary nodule and VATS is recommended preoperatively. It should apply in lesions, which are located subpleural and thoracoscopically not visible.

[Diagnosis and therapy of laryngitis gastrica]

We treated 64 patients with the diagnosis of laryngitis gastrica with Antra (Omeprazol) in doses of 10, 20, and 40 mg. To determine the success of the therapy, pH monitoring of the esophagus and hypopharynx, the voice status and measurement of vocal penetrating capacity were used. The results prove that a 20-mg dose of Antra is suitable for the therapy of laryngitis gastrica with a high rate of success. Problems which arose during the investigation, consequent changes of the original concept of the project as well as new aspects and questions which resulted from this are discussed with respect to further investigation.

CT-guided intervention using a patient laser marker system

To prove the usefulness of a simple laser marker system (LMS) in target definition as well as examination procedure for CT-guided interventions, 130 cases of diagnostic biopsies and lumbal sympathectomies were compared. In 75 cases LMS and in 55 cases a simple crossgrid was used. Taking advantage of the LMS, the parameters of intervention (cutaneous location, length, and angle) can be planned, exactly demonstrated, and it is possible to check the needle position during the whole procedure. Thus, the number of necessary control scans decreased to 30%, and corrections of needle location were reduced to approximately 30%. Moreover, the average target deviation of the needle decreased below 5 mm in 50% of cases, and the duration of interventional procedure was reduced considerably. It can be concluded that LMSs are recommended in CT-guided interventions for quality assurance, dose reduction, and improvement of handling. It will be especially advantageous in cases of small target volume, oblique needle path, and tilted gantry.

[24 hour pH monitoring of the hypopharymx]

Monitoring of pH of the esophagus is a routine diagnostic procedure, whereas until now pH-monitoring of the hypopharynx has been used only for scientific research. In the present study a critical evaluation scale was used to record the results of 112 patients who underwent pH monitoring to determine possible reflux. Since high refluxes often remain unnoticed clinically, further study is required in certain cases. The extent of reflux in the esophagus may not represent pathological changes in the hypopharynx. In such cases 24-h pH monitoring of the hypopharynx can be a useful diagnostic procedure and may also help detect the pathogenesis of "gastric laryngitis".

[Forgetting of word associations in relation to indicators of emotionality. A possibility for evaluating Freud's concept of repression?]

In replication of the well-known study by Levinger & Clark, 30 subjects were presented a list with 60 words under several conditions. In the first part of the experiment they had to tell the first word which came to mind as a response to the stimuli read by the experimenter. Reaction times and skin conductance reactions (SCRs) during associations were recorded. Immediately afterwards the list was read again with the instruction to recall the associations given before. In part 2 of the study, one week later, subjects had to recall again their first associations; in addition, they scaled the emotionality of the word stimuli. Intraindividual correlations were computed for indices of emotionality (reaction time, SCR, perceived emotionality) and forgetting in both short-term and long-term memory. Associations accompanied by larger electrodermal reaction and showing longer reaction time were more likely to be forgotten both for short and long intervals. This is in line with Freuds concept of repression. However, alternative explanations should also be discussed.

Downregulation of T helper type 1 immune response and altered pro-inflammatory and anti-inflammatory T cell cytokine balance following conventional but not laparoscopic surgery

BACKGROUND

The clinical advantages of laparoscopic procedures result from a minimized surgical trauma. The present study was performed to investigate immunosupression following laparoscopic operations as compared with open surgery. Our analysis focused on the T cell secretion of cytokines that regulate the critical balance of either T helper type-1 (Th1)- and Th2-mediated immune responses on pro- and antiinflammatory activities.

METHODS

In a prospective study, immunological data of 26 patients submitted to laparoscopic cholecystectomy (LCE) and 17 patients undergoing conventional cholecystectomy (CCE) for symptomatic cholecystolithiasis were compared. Patients with acute cholecystitis and patients developing postoperative complications or receiving immunosuppressive medication were excluded. Production of interferon (IFN)-gamma, interleukin (IL)-2, IL-4, tumor necrosis factor (TNF)-alpha, and IL-10 by isolated T cells stimulated by cross-linking of CD3 and CD28 was evaluated preoperatively as well as on postoperative days 1 and 6 or 7. Cytokines were measured by immunoenzymometric assay.

RESULTS

IFN-gamma, TNF-alpha, and IL-2 production by T cells decreased significantly by 48.3%, 36.6%, and 36.8%, respectively, on postoperative day 1 after CCE, but not after LCE. These results indicate severe suppression of Th1-type and proinflammatory cytokines after the open operation. In contrast, IL-4 and IL-10 did not show significant changes in either group suggesting that Th2 cell response and anti-inflammatory activity remained normal.

CONCLUSIONS

The present study shows that open, but not laparoscopic cholecystectomy is associated with a marked suppression of T lymphocytes functions as indicated by deregulation of both the Th1/Th2 and the pro-/anti-inflammatory cytokine balance. The results therefore suggest that downregulation of Th1 cell-mediated immune response and pro-inflammatory activity of T cells is a hallmark of open, but not laparoscopic surgery.

Normal T lymphocyte and monocyte function after minimally invasive surgery

BACKGROUND

The aim of this study was to evaluate immune defense mechanisms after laparoscopic (LCHE) and open cholecystectomy (CHE), particularly with regard to monocyte and T-lymphocyte function.

METHODS

In a prospective study, we evaluated the following immunological data from 27 patients (21 women, six men; mean age, 47.2 years) submitted to elective LCHE and 14 patients (seven women, seven men; mean age, 60.8 years) undergoing elective CHE: T-lymphocyte proliferation (stimulated by SEA, SEB, TSST-1 with antigen presentation by patient monocytes), expression of cell surface molecules on monocytes (HLA-DR, CD80, L-Selectin), CD4+ T lymphocytes (HLA-DR, CD25, ICAM-1, L-Selectin), and granulocytes (L-Selectin). Blood samples were collected preoperatively and on postoperative days 1 and 6-7. Statistical analysis was performed using the Mann-Whitney U test for paired samples.

RESULTS

HLA-DR on monocytes significantly decreased after LCHE during the early postoperative course but returned to preoperative levels within 1 week. After CHE, significant downregulation of HLA-DR expression persisted throughout the whole observation period. This decrease, however, did not alter the antigen-presenting capacity of monocytes in both groups. Moreover, the APC-independent proliferative capacity of T lymphocytes was unimpaired. CD25 expression was significantly increased on postoperative day 1 after CHE but not after LCHE. Expression of HLA-DR, ICAM1, and L-Selection on CD4+ T cells was not altered in either group. CD80 on monocytes and L-Selection on monocytes and granulocytes remained unchanged after both procedures.

CONCLUSIONS

HLA-DR surface molecules on monocytes that are required for antigen presentation were significantly decreased in both groups; they returned to normal within 1 week after LCHE but not after CHE. However, the antigen-presenting capacity for monocytes remained normal in both groups. T-cell stimulation, reflected by an increase of CD25 expression, was observed only after CHE, not after LCHE. We therefore conclude that LCHE interferes less with immune defense than CHE; however, the clinical relevance of the changes noted after the open operation remains to be determined.

[CT-guided intervention by means of a laser marking and targeting aid]

PURPOSE

The present study evaluates the use of a laser guidance system for CT-guided intervention.

MATERIAL AND METHODS

94 cases of diagnostic biopsies and lumbar sympathectomies (54 cases with laser guidance system and 40 without) were compared.

RESULTS

Using the laser guidance system, the number of control scans decreased by 30 to 50%, and necessary corrections of needle location were reduced by a maximum of 30%. The average target deviation of the needle decreased to less than 5 mm in 50% of cases.

CONCLUSION

The laser guidance system is strongly recommended in CT-guided interventions for quality assurance and higher efficiency. The advantage is especially marked if the target area is small.

An examination of the dental state of an Egyptian mummy by means of computer tomography: a contribution to 'dentistry in Ancient Egypt'

In 1991 mummies from Leipzig collections were investigated by means of conventional X-ray techniques and by computer tomography. The dental state of one of these mummies prompted a re-examination of the question of whether a dental profession actually existed in Ancient Egypt or not. To answer this question, different types of source material are discussed.

Building and Refining Abstract Planning Cases by Change of Representation Language

Abstraction is one of the most promising approaches to improve the performance of problem solvers. In several domains abstraction by dropping sentences of a domain description -- as used in most hierarchical planners -- has proven useful. In this paper we present examples which illustrate significant drawbacks of abstraction by dropping sentences. To overcome these drawbacks, we propose a more general view of abstraction involving the change of representation language. We have developed a new abstraction methodology and a related sound and complete learning algorithm that allows the complete change of representation language of planning cases from concrete to abstract. However, to achieve a powerful change of the representation language, the abstract language itself as well as rules which describe admissible ways of abstracting states must be provided in the domain model. This new abstraction approach is the core of Paris (Plan Abstraction and Refinement in an Integrated System), a system in which abstract planning cases are automatically learned from given concrete cases. An empirical study in the domain of process planning in mechanical engineering shows significant advantages of the proposed reasoning from abstract cases over classical hierarchical planning.

[Improved measurement of vocal penetration]

By measuring the vocal penetration a characteristic feature of the efficiency is covered which is essential for all three parts of the communication chain of speech with special emphasis on the recipient. Results are expressed in decibel (AS) of a defined masking noise, at which 50% of the logatomes spoken by the test persons are recognized. The vocal efficiency is indicated by the sound pressure of the masking noise, subtracting the sound level of speech used. Individuals with a healthy voice lie within the range of 12-24 dB (AS), average value 20 dB(AS), patients affected with a vocal disorder lie within the range of 0-12 dB(AS), average value 9 dB(AS). The vocal penetration significantly correlates with the auditive features of the vocal swinging-in phase; it proves to be a sensitive indicator of treatment efficacy for dysphonia and a useful tool for predicting the vocal capacity in all voice professions.

H-ras-1 point mutations in soft tissue sarcomas

The H-ras-1 protooncogene is activated by single base substitutions occurring in either codon 12, 13, or 61. These mutations have been described with varying frequencies in several human tumor types. Since ras oncogenes were first discovered as the transforming sequences of Harvey and Kirsten murine sarcoma viruses (which also contain activating point mutations compared to the homologous cellular sequences), we wished to investigate the possibility that ras mutations might also occur in human sarcomas. We extracted DNA from six malignant fibrous histiocytomas (MFH), three embryonal rhabdomyosarcomas (ER), one alveolar rhabdomyosarcoma, one pleomorphic rhabdomyosarcoma, and one leiomyosarcoma. The DNA from regions flanking codons 12/13 and codon 61 was amplified by the polymerase chain reaction and sequenced with an automated DNA sequencer. As controls, we amplified and sequenced normal DNA (placenta) and DNA with known point mutations (T24 bladder carcinoma cells). We found three cases with mutations, all occurring in codon 12. One ER showed a G-to-T mutation in the second position of codon 12 (coding for valine instead of glycine). Two MFHs showed G-to-A mutations in the second position of codon 12 (coding for aspartic acid instead of glycine). Although a limited number of cases were sampled, we conclude that study of H-ras-1 mutations may be relevant to MFH and ER. Additional studies of N and K-ras mutations as well as more cases investigating H-ras will be required before we can ascertain the significance of ras mutations in the oncogenesis of human soft tissue sarcomas.

Nitrogen mustard as induction therapy for rheumatoid arthritis: clinical and immunologic effects

We treated 5 patients diagnosed with rheumatoid arthritis (RA) with nitrogen mustard (HN2) and monitored clinical and immunologic variables. HN2, 0.3 mg/kg ideal body weight was given over 7 days. Disease activity and immune function were monitored during and after treatment. Duration of morning stiffness (p = 0.0044), joint count (p = 0.0140), and assessment of pain (p = 0.0264) and function (p = 0.0057) improved by Day 6. T lymphocytes (p = 0.0060), especially T memory cells (CD4CD29; p = 0.0017) fell dramatically. HN2 is effective for rapidly gaining control of active RA. This effect is T cell specific.

Chronic fatigue syndrome

Fatigue is one of the most common complaints among patients seen in the primary care setting. Chronic fatigue syndrome, which has recently been called chronic fatigue immune dysfunction syndrome, is distinctive, with an abrupt onset of symptoms that wax and wane for at least six months. Usually there is low-grade fever, pharyngitis and tender, but not enlarged, lymph nodes. The fatigue can be disabling and is often made worse by physical activity. Some patients with this disorder have also been found to have highly characteristic immunologic abnormalities. Treatment can be rewarding and is based on patient education and support, exercise and symptomatic therapies for abnormal sleep patterns, musculoskeletal pain and other symptoms.

Correlation between the light diffraction pattern and the structure of a muscle fibre realized with Ewald's construction

Ewald's construction of reciprocal space is used to explain the diffraction pattern obtained by illumination of a skeletal muscle fibre with laser light. The question of whether the illuminated fibre segment acts as a monocrystal or as a conglomerate of crystallites is answered by determining the longitudinal extension of the layer lines; neither the whole muscle fibre nor the single myofibril acts as the diffracting unit. The characteristic fine structure within a layer line ('streaks') is explained by Ewald's formalism as being caused by diffraction from partial volumes of the illuminated fibre segment. These partial volumes constitute the main diffracting units. Any cross-section of a 100 micron diameter fibre contains 3-6 such units. They are delineated from each other by the skew of the diffracting planes with respect to the fibre axis, and possibly by small differences in sarcomere length. Within a unit, skew angle and sarcomere length are nearly constant. Light intensity measurements along the length of a layer line at various tilt angles (omega) between fibre and beam axis provide an overview of the size and the skew angle of the various diffracting units within the illuminated fibre segment. The cross-sections of the diffracting units were measured in 'mini'-omega-scans of streaks created by them and from the maximal streak length. In general, the units had noncircular cross-section, the length of the main axis ranging between 10 micron and the fibre diameter. The axial extensions of the diffracting units determined in fibre length scans was 100-300 micron. The results of diffraction experiments reported in the literature as well as the data from light and electron microscopy are in agreement with the fibre structure suggested above. Sarcomere length determination by light diffractometry is discussed within the framework of the Ewald formalism, and recommendations for an experimental procedure are given.

Pituitary and adrenal hormones in patients after myocardial infarction under ergometer load

The levels of human growth hormone (HGH), ACTH and cortisol in the plasma of 100 middle-aged men were measured by means of radioimmunoassay (12 patients in the phase of hospitalization after myocardial infarction, 47 patients in convalescence, 31 patients in post-convalescence, 10 healthy men). Twenty patients in the phase of convalescence and all patients in post-convalescence did exercises on bicycle ergometer with submaximal loading. Patients after myocardial infarction showed significantly lower basic levels of HGH than healthy persons, and the increase in the HGH level induced by exercise was significantly lower. The hormones ACTH and cortisol showed only slight differences. The secretion of the pituitary hormones, mainly HGH, seems to be altered in patients after myocardial infarction.

[Chondrocalcinosis of the intervertebral disks]

Intervertebral discs removed in cases of disc herniation were investigated by polarized light microscopy. In about 4% of all cases crystalline deposits were detected. The crystals were characterized by different staining methods, scanning electron microscopy and X-ray diffraction. From the results it is concluded that the crystalline deposits are usually composed of calcium pyrophosphate dihydrate. With regard to the age of the patients it became obvious that there was an increased frequency of crystalline deposits with increasing age. Therefore it is assumed that calcium pyrophosphate deposits in intervertebral discs are an agerelated phenomenon as is known from chondrocalcinosis of other joints.

Determination of total insulin (TIRI) in plasma of insulin-treated diabetics and newborn infants of insulin-treated diabetic mothers

Plasma of insulin-treated diabetics and of newborn infants of insulin-treated diabetic mothers contains insulin antibodies which invalidates the radioimmunoassay of insulin. Therefore, the endogenous insulin antibody complex must be splitted at a pH lower than 5 and the total IRI (TIRI) is separated by ethanol extraction. It was investigated the recovery rate in dependence upon plasma volume used for extraction. By reduction of used plasma volume from 500 to 200 mul per extraction the recovery rate was increased from 65.1 +/- 8.4 to 88.3 +/- 4.2% (mean +/- SEM). The low plasma volume of 200 mul for TIRI extraction made it possible to determine TIRI during glucose loads of newborn infants. To eliminate different conditions of incubation for standard and unknown plasma samples the TIRI levels were computed by means of so-called "extracted" standard curve, obtained with extracted insulin from standard insulin dilution in insulin-free pooled human plasma. Using the described method a temporary regeneration of insulin secretion of a newly diagnosed juvenile diabetic after insulin treatment could be shown. In contrast to newborn infants of healthy mothers a biphasic/insulin release was found during the intravenous glucose loads in newborn infants of insulin-treated diabetic mothers.