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M Thoma

Publications and source records attributed to M Thoma.

At least 19 recordsLinked to original sources
PubMed2006

The suturing concept for laparoscopic mesh fixation in ventral and incisional hernia repair: Mid-term analysis of 400 cases.

BACKGROUND: The authors describe a minimally invasive treatment of moderate to large incisional and ventral hernia defects using Parietex composite mesh. METHODS: All defects are closed laparoscopically or through a minilaparotomy using sutures, and the composite mesh is fixed intraperitonally using transabdominal fixation with nonabsorbable sutures to avoid the use of staple or tack fixation, which has been associated with various complications, including major loop adhesion and mesh migration. The midterm results for 400 patients are presented in terms of efficacy and safety. RESULTS: During a mean follow-up period of 28 months for 80% of the patients, the median operating time was 74 min and the median hospital stay was 3 days. There were eight seromas (2%), all on large defects. Transient pain was experienced by 10 patients (2.5%), and resolved over time with analgesic treatment. There was one early case of sepsis (0.25%), attributable to secondary breakdown of the bowel wall in a case of recurrent incisional hernia, which led to removal of the mesh. Residual chronic parietal pain was reported for 10 patients (2.5%), 2 of whom were released after excision of neuroma; 3 trocar-site herniations (0.75%); and lipoma formation on the site of the hernia sac in 6 cases (1.5%). CONCLUSION: Laparoscopic ventral hernia treatment using Parietex composite mesh is an effective and safe procedure. Morbidity and recurrence rates are low, and the 2-year outcomes are promising, with no prosthesis migration or complication related to intraperitoneal positioning of the mesh.

Adult↗
PubMed2002

Radio-chemotherapy as a preoperative treatment for advanced rectal cancer. Evaluation of down-staging and morbidity.

BACKGROUND: The standard therapy for patients with clinically resectable rectal cancer is generally considered to be surgery. If the patient is diagnosed with advanced disease, postoperative radio-chemotherapy (RCT) is usually recommended. In our study we aimed to investigate and analyze the effectiveness and toxicity of preoperative pelvic radiotherapy in combination with 5-fluorouracil (5-FU) in locally advanced rectal cancer. PATIENTS AND METHODS: From June 1999 to September 2001 we evaluated 50 consecutive patients [37 male and 13 female; average age 65.1 (range 46-79.5) years] with locally advanced rectal carcinoma. 32 patients were staged as uT3, 14 as uT4, and 4 as uT2. Regarding N-staging, 22 patients were diagnosed as uN0. 2 patients had distant metastases, with liver metastases in both instances. Conformal irradiation was performed with a box technique (4-field technique) with a dose of 45 Gy (5 x 1.8 Gy per week for a total of 25 sessions). From days 1-5 and 29-33, all patients received 5-FU (500 mg/m(2 ) per day, as a continuous i.v. injection). RESULTS: Remission was observed in 28 patients (56%), with down-staging of at least one T-stage. A better success rate was achieved for patients with deep-seated tumors (64% of the patients in this group). Complete remission was observed in 4 patients (8.0%) and progression in 3 (6.0%). 15 patients had no detectable change in tumor staging (30.0%). A surgical R0 resection could be achieved in 43 patients, an R1 resection (minimal margin) in 7. Side effects and toxicity (common toxicity criteria) of RCT included grade I-II dysuria in 5 patients (10%), grade I-II diarrhea in 20 patients (40%), and severe diarrhea in 2 patients (4.0%). Grade I-II skin reaction was noticed in 22 patients (44.0%), severe skin reaction only in 1 patient. Regarding acute postoperative morbidity, abscess and fistula formation was noted in 8 patients (16.0%), with anastomosis leakage in 7 (14%). CONCLUSION: Preoperative radiotherapy appears to be a feasible therapeutic approach with moderate toxicity and the potential to induce down-staging. The data presented in this study confirm the preliminary reports on this neoadjuvant treatment.

Adult↗
PubMed2000

First Results from Viper: Detection of Small-scale Anisotropy at 40 GHz.

Results of a search for small-scale anisotropy in the cosmic microwave background (CMB) are presented. Observations were made at the South Pole using the Viper telescope, with a 0&fdg;26 (FWHM) beam and a passband centered at 40 GHz. Anisotropy band-power measurements in bands spanning the range of l in which the first acoustic peak is expected (bands centered at l=108, 173, 237, 263, 422, and 589) are reported. Statistically significant CMB anisotropy is detected in all bands.

Journal Article↗
PubMed1999

Thrombin and mast cell tryptase regulate guinea-pig myenteric neurons through proteinase-activated receptors-1 and -2.

1. Proteases regulate cells by cleaving proteinase-activated receptors (PARs). Thrombin and trypsin cleave PAR-1 and PAR-2 on neurons and astrocytes of the brain to regulate morphology, growth and survival. We hypothesized that thrombin and mast cell tryptase, which are generated and released during trauma and inflammation, regulate enteric neurons by cleaving PAR-1 and PAR-2. 2. We detected immunoreactive PAR-1 and PAR-2 in > 60 % of neurons from the myenteric plexus of guinea-pig small intestine in primary culture. A large proportion of neurons that expressed substance P, vasoactive intestinal peptide or nitric oxide synthase also expressed PAR-1 and PAR-2. We confirmed expression of PAR-1 and PAR-2 in the myenteric plexus by RT-PCR using primers based on sequences of cloned guinea-pig receptors. 3. Thrombin, trypsin, tryptase, a filtrate from degranulated mast cells, and peptides corresponding to the tethered ligand domains of PAR-1 and PAR-2 increased [Ca2+]i in > 50 % of cultured myenteric neurons. Approximately 60 % of neurons that responded to PAR-1 agonists responded to PAR-2 agonists, and > 90 % of PAR-1 and PAR-2 responsive neurons responded to ATP. 4. These results indicate that a large proportion of myenteric neurons that express excitatory and inhibitory neurotransmitters and purinoceptors also express PAR-1 and PAR-2. Thrombin and tryptase may excite myenteric neurons during trauma and inflammation when prothrombin is activated and mast cells degranulate. This novel action of serine proteases probably contributes to abnormal neurotransmission and motility in the inflamed intestine.

Animals↗
PubMed1999

Oxygen, pH value, and carbon source induced changes of the mode of oscillation in synchronous continuous culture of Saccharomyces cerevisiae.

Oscillations of measured process parameters occur in continuous cultures of Saccharomyces cerevisiae owing to a partial synchronization of budding. Intentional changes of the oxygen concentration, pH value, and carbon source cause effects on the period length similar to those known from variations of the dilution rate. The generation times of parent and daughter cells frequently differ in synchronous culture. To analyze the oscillation the term mode IJ of oscillation is used, which is defined as the ratio IJ of the generation times of parent and daughter cells. When the dissolved oxygen concentration was reduced to zero, the mode of oscillation changed within two periods from mode 12 to mode 11, caused by a decrease of the generation time of daughter cells and an increase of that of the parent cells. When the pH value was slowly reduced from 5.0 to 3.9, a change from mode 112 to mode 13 was observed. Mode 13, representing one parent and three daughter cell populations (the start of budding of each of the three being delayed by one period), denotes an elongated generation time of the daughter cells compared to mode 112, marked by one parent and two different daughter cell classes. When the carbon source galactose was replaced by glucose a mode change from mode 12 to mode 11 was observed. This alteration of the mode was found to be dependent on the status of the cell cycle at the time when the carbon source is changed. The population distribution in batch cultures with glucose or galactose as a substrate was analysed by dyeing the DNA and counting the bud scars. Galactose provoked higher growth rates for the older cells. According to the model for stationary synchronous growth parameters like DO, pH value or the type of carbon source can be varied within a certain range without effecting the period length. If the variation imposes a certain stress, the culture switches to a new mode. These kinds of parameters therefore provide selective measures to influence the period lengths and the modes of oscillation.

Bioreactors↗
PubMed1999

Coagulative interstitial laser-induced thermotherapy of benign prostatic hyperplasia: online imaging with a T2-weighted fast spin-echo MR sequence--experience in six patients.

PURPOSE: To determine if hypointense lesions clearly outline on T2-weighted fast spin-echo (SE) magnetic resonance (MR) images obtained during coagulative interstitial laser-induced thermotherapy (LITT) of a prostate with benign hyperplasia. MATERIALS AND METHODS: In six patients with benign prostatic hyperplasia (BPH), 12 LITT treatments were followed online with repetitive axial T2-weighted fast SE imaging (repetition time, 3,700 msec; echo time, 138 msec; acquisition time, 19 seconds). Development, time course, correlation with interstitial tissue temperature, and diameters of hypointense lesions around the laser diffusor tip were investigated. Lesion diameters on T2-weighted images acquired during LITT were compared with diameters of final lesions on T2-weighted images and unperfused lesions on enhanced T1-weighted SE images obtained at the end of therapy. RESULTS: Hypointense lesions developed within 20-40 seconds of LITT. Average correlation coefficients between interstitial temperature development and signal intensity development were 0.92 during LITT and 0.90 after LITT. Regression slopes were significantly steeper during LITT (0.67% signal intensity change per degree Celsius) than after LITT (0.47% per degree Celsius; P = .038). Lesions remained visible after LITT for all procedures. Average maximum diameters of lesions were 1-3 mm larger during LITT than after LITT (P = .0006-.019). CONCLUSION: Repetitive T2-weighted fast SE MR imaging during interstitial coagulative LITT of BPH demonstrates the development of permanent hypointense prostate lesions. However, posttherapeutic lesion diameters tend to be overestimated during LITT.

Aged↗
PubMed1998

Effect of the dilution rate on the mode of oscillation in continuous cultures of Saccharomyces cerevisiae.

The growth properties of the asymmetric budding yeast Saccharomyces cerevisiae were analysed during spontaneous oscillations in continuous cultures at varying dilution rates D. The length of the oscillation period changed between 1.4 and 14 h in response to the decrease of dilution rate from 0.15 to 0.05 h-1. The distribution of parent and daughter cells in the population was determined microscopically after staining the bud scars and DNA. Most of the data obtained fits a theoretical population balance model assuming two-classes of subpopulations and integer ratios between the generation times of both classes. Some data has to be described by an extended population model assuming there is one parent and two daughter cell classes. How changes of dilution rate may cause an accidental switch of the mode of oscillation is demonstrated. Glucose consumption and metabolite production were measured off-line by enzymatic methods and gas exchange was monitored on-line. All these data of one period point to internal and external signals responsible for the synchronisation of the cell cycle.

Bioreactors↗
PubMed1998

Prediction of toxicity but not of clinical course by determining carboplatin exposure in patients with epithelial ovarian cancer treated with a combination of carboplatin and cisplatin.

We present the data from 105 patients with primary epithelial ovarian cancer, who received up to 6 cycles of carboplatin (300 mg/m2) and cisplatin (100 mg/m2) as one treatment arm of a prospective randomized trial. Values for first-course carboplatin area-under-the-curve (AUC) were determined retrospectively. WHO grade 3-4 thrombocytopenia was found in 10% of patients with low AUC (AUC <4 mg/ml x min), but in 44.6% of patients with high AUC (AUC 4 mg/ml x min) (chi-square p<0.0001). No single case of ototoxicity was found in the low AUC group but in 12% of patients in the high AUC group (chi-square p=0.003). Determination of carboplatin AUC may prevent ototoxicity and severe thrombocytopenia for the first cycle of combined treatment with carboplatin and cisplatin.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

[Initial results with MRI-controlled laser-induced interstitial thermotherapy of head and neck tumors].

Laser-induced interstitial thermo-therapy (LITT) was introduced as a minimally invasive form of therapy for tumors in different anatomic regions. However, in the orofacial region, it has not been used so far for inoperable T4 carcinomas. Since vascular and neural structures are often close to the tumor or are even involved, online monitoring of LITT is necessary. The aim of our study was to establish a method of monitoring LITT with MRI (magnetic resonance imaging) in the orofacial region. Five patients with T4 carcinomas of the orofacial region underwent LITT under anesthesia. A 1.5 T whole-body imager with a circular polarized head coil was used. Before and after the intervention, the region of interest was studied using T1- and T2-weighted sequences in axial and coronal planes, with and without contrast enhancement (intravenous Gd-DTPA). Temperature distribution was monitored with a T1-weighted 2D-FLASH (fast low angle shot) sequence. The positioning of the optical fibers was monitored with MRI. Nd:YAG laser equipment was used for laser application. The necrosis was best seen on contrast-enhanced MRI. Immediately after LITT, the outcome could be determined by MRI. We proposed that MRI-guided LITT be used for neoplasms in the orofacial region at advanced stages.

Aged↗
PubMed1996

[MRI monitoring before, during and after interstitial laser-induced hyperthermia of benign prostatic hyperplasia. Initial clinical experiences].

PURPOSE: To assess the clinical value of MRI in patients with benign prostatic hyperplasia (BPH) before, during, and after interstitial laser-induced thermotherapy (LITT) of the prostate. METHODS: Ten patients with symptomatic BPH had MRI examinations of the prostate 48 h before and after LITT. Online monitoring with MRI at 1.5 T of interstitial Nd:YAG laser energy deposition in the prostate was performed in two patients, repeating a T1-weighted FLASH sequence (TR 100 ms, TE 5 ms, flip angle 90 degrees) every 20 s. Follow-up MRI examinations 2-3 weeks, 6-8 weeks, and 6-12 months after LITT were carried out in eight patients, using T2-weighted FSE images and contrast-enhanced T1-weighted SE images. RESULTS: The prostate was well delineated in all patients on T2-weighted FSE images, with a rather homogeneous peripheral gland and an inhomogeneous central gland. Volume measurements yielded reproducibilities of 3.2%-4.7%. Signal intensity in the FLASH sequence decreased during LITT, both in the prostate in vivo and in specimens of bovine prostate and seminal vesicles in vitro, with signal developments running in parallel. Areas of energy deposition and signal alteration were not sharply delineated. The latter margin of the laser-induced lesions could not be predicted from the FLASH images, while the tip of the laser fibre was easily recognized. Contrast-enhanced T1-weighted MR images immediately after LITT clearly demarcated low signal intensity laser lesions from high signal intensity surrounding prostate tissue. Follow-up examinations showed a decrease of 20% of prostate volume over a period of 6-12 months after LITT. Correlation between prostate volume development and lesion volume alteration was 0.85-0.90 (P = 0.002-0.007) at all follow-up times. CONCLUSIONS: MRI allows rather precise recognition of intraprostatic alterations after LITT, including volume changes over a period of up to 1 year after therapy that can be predicted immediately after LITT. While laser energy deposition in the prostate can be monitored by MRI with T1-weighted FLASH sequences as a function of temperature alteration, it is not possible to determine the lesion margins immediately from the FLASH images. Online temperature development map generation will be necessary to influence on-going LITT procedures with MRI.

Aged↗
PubMed1995

Microvessel density and vessel invasion in lymph-node-negative breast cancer: effect on recurrence-free survival.

Microvessel density (MVD) and blood and lymphatic vessel invasion (BLVI) were investigated with regard to their influence on the disease-free survival (DFS) in node-negative breast cancer patients. Paraffin embedded microsections of 230 patients with T1,2 N0 breast cancer were immunohistochemically stained for factor VIII-related antigen. Every cluster consisting of more than highlighted endothelial cells was considered a countable microvessel. MVD was counted in 4 fields of 0.25 mm2 each. All MVD values are given as value for the sum of 4 fields of 0.25 mm2 each, that is, I mm2. BLVI was considered positive, when at least one tumor cell could be identified in a stained lumen. Out of 230 patients, 49 experienced local or distant recurrence and had a mean MVD of 72.4/mm2, whereas 181 patients who lived without recurrent disease had a mean MVD of 45.3/mm2. BLVI was negative in 6.2% of the cases with and in 93.8% of the cases without recurrent disease. BLVI was positive in 59.4% of the cases without and 40.6% of the cases with recurrent disease. MVD and BLVI remained the only significant prognostic factors of DFS in the Cox-Model. Tumor size, histological grade, and hormonal-receptor status were not prognostically relevant in the Cox-model. 10-year-DFS was 93.3% in BLVI-negative/MVD < or = 40/mm2 patients, 88.1% when MVD was high or BLVI was positive and 48.9% in BLVI positive/MVD < or = 40/mm2 patients. Our present data indicate that MVD and BLVI identify a very-low risk group among node-negative breast cancer patients, who will not benefit from systemic adjuvant therapy. MVD and BLVI should be used as stratification criteria in clinical trails on node-negative breast cancer patients.

Adult↗
PubMed1994

Apert syndrome, an antenatal ultrasound detected case.

Apert's syndrome or acrocephalosyndactyly type I is an autosomal dominant craniosynostosis syndrome with abnormalities of the hands and feet. Most cases occur as new mutations. Mental retardation is frequent because of central nervous system abnormalities. A case of Apert's syndrome detected by antenatal ultrasound examination is reported by the authors.

Abortion, Eugenic↗
PubMed1994

[Anorectal traumas by impalement in children. Apropos of 3 cases].

Traumatic impalement is an exceptional cause of anorectal lesions in the child. The clinical diagnosis is sometimes difficult and associated lesions raise the problem of the most appropriate exploratory examination. Based on our experience with three cases, we would emphasize the usefulness of hydrosoluble enema study prudently performed by the surgeon during the preoperative work-up. The precise localization of the lesions must be obtained with careful emergency exploration before repair. Treatment of the trauma includes lavage, drainage and sometimes colostomy. Antibiotics must always be prescribed. Early complications are dominated by infection and long-term sequellae, requiring a long follow-up.

Adolescent↗
PubMed1994

[Characteristics of fractures of the distal part of the clavicle in children].

Fractures of the clavicle are frequent in children and mostly affect the middle third. On the other hand, traumatic fractures of both medial and lateral thirds of the clavicle are rare. The lesions have special characteristics: difficulty in diagnosis for the medial third; risk of callus formation in the absence of surgical reduction of the lateral third. The authors report two observations of fractures of the medial and lateral thirds of the clavicle; they insist on the value of investigation by CT scan.

Child↗