Biomedical subjects

K Kraft

Publications and source records attributed to K Kraft.

At least 19 recordsLinked to original sources

PubMed2006

Flow cytometric S-phase fraction contributes to diagnosis of diploid malignant salivary gland tumours.

DNA ploidy studies on salivary gland tumours have shown that the proportion of aneuploid cases, although confined to the malignant entities, is considerably lower than for other solid malignancies. To analyse whether the S-phase fraction (SPF) may contribute to discrimination of diploid malignant from benign tumours, DNA flow cytometric data from 45 different malignant salivary gland tumours was compared with that of 121 pleomorphic adenomas. All benign tumours were diploid. Twelve malignant tumours contained aneuploid cell populations. The SPF values for diploid malignancies ranged between 0.9% and 11.0% (mean 3.9%), and between 0.5% and 7.9% (mean 2.7%) for pleomorphic adenomas. A 4% cut-off value gained statistical significance for discriminating diploid malignant tumours from pleomorphic adenomas (P<0.01). The sensitivity for SPF>4% was 46% and the positive predictive value was 40%. A sensitivity of 60% and a positive predictive value of 54% was achieved by combining aneuploidy and SPF>4%. These results show that DNA flow cytometry may contribute to diagnostic assessment in salivary gland tumours.

Adenoma, Pleomorphic↗

PubMed2006

[Leiomyosarcoma of the larynx].

Leiomyosarcoma is usually found in the female genital tract, retroperitoneum, the wall of the gastrointestinal tract and subcutaneous tissues. An appearance of this malignant tumor in the larynx is extremely rare and may be difficult to diagnose. Because of its rarity, little information exists on management and prognosis. We report on a 64-year old male with a supraglottic leiomyosarcoma who was treated with supraglottic laryngectomy and postoperative radiotherapy. After 19 months the patient was well and free of disease. The most commonly used diagnostic and therapeutic procedures are analysed in a review of the 46 published cases of laryngeal leiomyosarcoma.

Combined Modality Therapy↗

PubMed2005

Laparoscopic hernia repair--TAPP or/and TEP?

BACKGROUND: Of various endoscopic hernia repair procedures, TAPP and TEP have been selected for routine use. METHODS: Results from Medline research were analysed. RESULTS: There is a similar risk for postoperative morbidity for both techniques. The recurrence rate in large single-centre series is between 0% and 3.4%. There were numerous indications for both procedures, whereby a transperitoneal TAPP can also be applied in cases of previous preperitoneal operations. CONCLUSION: Randomised trials comparing both methods of hernia repair are lacking. Seven non-randomised studies showed no differences in recurrence rate and morbidity. In general the learning curve for is shorter in favour of TAPP repair.

Hernia, Inguinal↗

PubMed2005

[Cavernous hemangioma of the parotid gland in adults].

Parotid hemangiomas are rare in adults. Whereas both capillary and cavernous hemangiomas are seen in children, only cavernous hemangiomas have thus far been reported in adults. Clinically, cavernous hemangiomas usually present as slowly growing, soft or firm, movable, painless parotid masses. Severe pain and swelling can occur, however, depending on the size of the hemangioma or in particular in the presence of acute hemorrhage or thrombosis. CT and MRI are the diagnostic tools of choice. Prior to surgery, magnetic resonance angiography or intra-arterial digital subtraction angiography should be performed to investigate the vascular supply of the tumor. Surgical excision is the treatment of choice for small lesions. Large cavernous hemangiomas usually require superficial or total parotidectomy. Especially in the case of extended lesions, the facial nerve may be difficult to identify and should be monitored intraoperatively.

Adult↗

PubMed2005

[Ductal carcinoma of the parotid gland with the clinical picture of obstructive sialadenitis].

Salivary duct carcinoma is a highly malignant tumor. Pain, facial nerve palsy, perineural and lymphatic invasion are common findings, as well as an extensive cervical lymph node involvement and distant metastasis. However, occasionally, as in the case presented, the clinical features of this tumor may resemble obstructive sialadenitis and thus cause a delay in appropriate treatment. Although salivary duct carcinoma exhibits an unpredictable clinical course and a poor overall prognosis, total parotidectomy with neck dissection and adjunctive radiation therapy appear to be appropriate for local and regional control of this aggressive neoplasm.

Adult↗

PubMed2005

Limited-dose Daclizumab versus Basiliximab: a comparison of cost and efficacy in preventing acute rejection.

The purpose of this study was to compare the efficacy and cost of the limited-dose Daclizumab regimen to that of the standard-dose Basiliximab regimen. Two antibody induction regimens were compared in patients aged 18 years and older who received renal transplants from January 2002 to September 2003 and completed interleukin (IL)-2R antibody induction with standard-dose Basiliximab (20 mg x 2 doses) or limited-dose Daclizumab (1 mg/kg x 2 doses). The primary outcome measure was the incidence of acute rejection. Secondary outcomes included cost, changes in serum creatinine level, and delayed graft function. Of the 46 patients randomized, 42 patients completed the 6-month follow-up. Mean serum creatinine level at time of discharge was originally higher in the limited-dose Daclizumab group than the standard-dose Basiliximab group (1.89 vs 1.57, respectively). By 1, 3, and 6 months, mean serum creatinine values were similar between both groups, with a trend toward lower mean serum creatinine values in the limited-dose Daclizumab group. The incidence of acute rejection was also similar between the groups (6% vs 7%). The average cost difference between the 2 regimens was approximately $715. This study suggests that a limited-dose Daclizumab regimen may be an efficacious and less costly alternative to the standard-dose Basiliximab regimen for antibody induction therapy following renal transplantation.

Adult↗

PubMed2004

The AESOP robot system in laparoscopic surgery: increased risk or advantage for surgeon and patient?

BACKGROUND: The aim of this study was to examine the advantages and risks of the Automated Endoscopic System for Optical Positioning (AESOP) 3000 robot system during uncomplicated laparoscopic cholecystectomies or laparoscopic hernioplasty. METHODS: In a randomized study, we examined two groups of 120 patients each with the diagnosis cholecystolithiasis respectively the unilateral inguinal hernia. We worked with the AESOP 3000, a robotic arm system that is voice-controlled by the surgeon. The subjective and objective comfort of the surgeon as well as the course and length of the operation were measured. RESULTS: The robot-assisted operations required significantly longer preparation and operation times. With regard to the necessary commands and manual camera corrections, the assistant group was favored. The same was true for the subjective evaluation of the surgical course by the surgeon. CONCLUSIONS: Our study showed that the use of AESOP during laparoscopic cholecystectomy and hernioplasty is possible in 94% of all cases. The surgeon must accept a definite loss of comfort as well as a certain loss of time against the advantage of saving on personnel.

Adolescent↗

PubMed2004

[Naturopathy in rehabilitation--a logical option in the German health system].

The present restructuring of the German health system is a reaction to the changing demands resulting from demographic and financial developments. In this context, an increase in patients autonomy is urgently needed which is only possible in cooperation with this group. The rehabilitative sector of the health system with its biopsychosocial model of diseases offers still heavily overlooked solutions, in particular because of its extensive use of complementary medicine, which has a high degree of acceptance among patients and the general population.

Combined Modality Therapy↗

PubMed2004

[Clarification of tissue contamination in a suspected adenocarcinoma of the spermatic cord by microsatellite analysis].

Malignant tumors of the spermatic cord are rare with primary neoplasms being mostly sarcomas. Adenocarcinomas of the spermatic cord are found extremely seldom and are predominantly metastases of extragonadal tumors. We present an asymptomatic 47-year-old patient who was referred to our clinic after a vasectomy had been performed and the histological examination had surprisingly shown adenocarcinoma of the left spermatic cord. Extensive laboratory analysis and diagnostic imaging did not demonstrate any testicular, spermatic cord, or extragonadal tumor. To exclude a mix-up of specimens, we performed DNA analysis. Microsatellite PCR clearly demonstrated the different origins of the tumor and the vasectomy specimen. Specimen mix-up or contamination may happen in any phase of surgical or pathological processing. In any case of clinical uncertainty concerning the identity of a tissue specimen, this possibility has to be taken into consideration. Microsatellite PCR can clearly identify the origin of tissue samples even on embedded material.

Adenocarcinoma↗

PubMed2003

Diagnosis and classification of inguinal hernias.

BACKGROUND: The aim of this prospective clinical study was to determine whether the presence of a hernia, its size, and its type can be established preoperatively by clinical and ultrasound, examination. METHODS: The study population comprised 220 consecutive patients referred to our department for the surgical management of an inguinal hernia. On admission, both inguinal regions were examined clinically and by ultrasound. All patients were operated on laparoscopically. RESULTS: In regard to the intraoperative findings for both inguinal regions, clinical and ultrasound examination for the diagnosis of inguinal hernia yielded a high total rate of accuracy of 93% respective 94%. However, when the same methods were used to differentiate between lateral and medial hernia, the total rate of accuracy fell to only 54% respective 62%. In the determination of inguinal hernia size, it was even lower: 50% respective 53%. CONCLUSIONS: Although a diagnosis of inguinal hernia can be established reliably by clinical and ultrasound examination, only an approximate classification is possible by these methods.

Adult↗

PubMed2003

Significance of apoptosis in metastasizing testis tumors.

Testis tumors of embryonal origin (ten metastasized, six non-metastasized) and 17 mixed testis cell carcinomas (eight metastasized, nine non-metastasized) were examined. A triple immunofluorescence microscopic labeling procedure allowed the simultaneous detection of two features of apoptosis, namely morphological changes in the nucleus (DNA condensation visualized by DAPI staining) and the process of DNA fragmentation (TdT-assay) in tumor cells as well as T-cells (recognized by their CD45RO epitope). Both methods for apoptosis detection showed similar apoptotic indices (AI) only in 2.6% of all tumors. Most tumors (81.6%) showed more cells with DNA fragments than condensed chromatin, but in a number of cases (10.5%) the opposite pattern was found. These data add to the few published in vivo examinations of apoptosis using different methods and help to explain differences in the judgment of apoptosis significance for tumor prognosis. With regard to tumorigenesis, non-metastasized testis tumors were characterized by higher AIs of tumor cells and T-cells compared with metastasized tumors, which could be interpreted as a characteristic of tumors in an earlier stage of their development into an apoptosis-resistant phenotype. For the first time, in metastasized tumors a 5 to 25-fold increase of the T-cell's AIs over the corresponding AIs of tumor cells was shown. This suggests a successful counterattack of tumor cells, thus supporting the process of metastasis. However, only ten out of 33 tumors revealed these AI changes, which again highlights that tumor biology cannot be predicted by a single parametric approach. It remains to be seen whether these characteristics might be suitable for a reliable prediction of metastasis.

Adult↗

PubMed2003

Expression of retinoblastoma gene product in respiratory epithelium and sinonasal neoplasms: relationship with p16 and cyclin D1 expression.

Transition from G1 to S phase of the cell cycle is mediated by interactions between the Retinoblastoma gene product (pRb), p16, and cyclin D1. To determine the expression of these proteins in the sinonasal mucosa immunohistochemistry was carried out on archived tissue sections from 46 patients (37 men, 9 women, age range 17 to 82 years, median 55 years). Nuclear immunostaining for these proteins was assessed and the expression rates (percentages of immunoreactive nuclei) in normal respiratory epithelium, inverted sinonasal papillomas, cylindrical (oncocytic) sinonasal papillomas, and squamous cell carcinomas were compared. Normal respiratory epithelium showed significantly higher pRb expression in surface cells compared to basal cells (p < 0.05). In contrast, abundant pRb expression in surface and basal cells was detected in columnar differentiation in sinonasal papillomas and adjacent mucosa. Cuboidal and squamous metaplasia in inverted papillomas showed significantly reduced pRb expression in surface cells compared to columnar epithelium in inverted papillomas (p < 0.05, respectively). Expression of p16 was detected in all epithelial cell layers of normal respiratory epithelium, sinonasal papillomas, and adjacent mucosa. Cuboidal and squamous metaplasia in inverted papillomas showed increased p16 expression in surface cells compared to columnar epithelium in inverted papillomas (p < 0.05 between squamous metaplasia and columnar epithelium). Sinonasal squamous cell carcinomas showed the coexpression of pRb and p16. Expression rates of cyclin D1 higher than 10% were detected only in invasive carcinomas but not in carcinoma in situ, sinonasal papillomas or respiratory epithelium. Conclusively, pRb expression accompanies terminal differentiation in columnar surface cells. Expression of pRb in proliferating basal cells is present in sinonasal papillomas and adjacent mucosa but not in normal respiratory epithelium. Cuboidal and squamous metaplasia in inverted papillomas involves downregulation of pRb expression along with increased p16 expression in surface cells. Sinonasal squamous cell carcinomas coexpress pRb and p16. Overexpression of cyclin D1 in sinonasal lesions is confined to invasive squamous cell carcinomas.

Carcinoma, Squamous Cell↗

PubMed2002

Laparoscopic transperitoneal procedure for routine repair of groin hernia.

BACKGROUND: Laparoscopic transperitoneal hernioplasty (TAPP) repair of inguinal hernias is thought to be a difficult surgical technique with high complication rates. The present study evaluated TAPP based on prospective documentation. METHODS: The primary aim of the study was analysis of the individual learning curve, comparing consultants with trainees. Secondary endpoints included postoperative morbidity, time of disability and rate of recurrence. RESULTS: A total of 8050 TAPP repairs have been performed since 1993. By 2001, 99.9 per cent of all hernia repairs were done by TAPP. The median operation time dropped from 50 min in the first 600 cases to 42 min thereafter. The morbidity rate decreased from 9.3 to 2.6 per cent, and the rate of recurrence from 4.8 to 0.4 per cent. Within the same interval the proportion of training procedures increased from 1.7 to 44.9 per cent in 2001. Morbidity and recurrence rates were similar for trainees and consultants. CONCLUSION: TAPP is an effective and safe technique. It can be performed in a standard way for all inguinal and femoral hernias. The present results indicate that TAPP is possible in a routine setting, as well as in the training situation for young surgeons.

Adolescent↗

PubMed2001

Simultaneous bilateral laparoscopic inguinal hernia repair: an analysis of 1336 consecutive cases at a single center.

BACKGROUND: We compare the use of unilateral and simultaneous bilateral laparoscopic hernioplasty [transabdominal preperitoneal patch (TAPP)] METHOD: We employed a prospective consecutive single-center trial lasting from April 1993 to December 2000. RESULTS: In our study, 5524 consecutive patients underwent 6860 laparoscopic hernia repairs. The median age in group A (unilateral repair, n = 4188) was 58 years (16-94 years), and that in group B (simultaneous bilateral repair, n = 1336) was 60 years (19-97 years) in (simultaneous bilateral repair, n = 1336). Morbidity in group A was 3.2% (135/4188) with a 0.6% reoperation rate (24/4188); in group B morbidity was 5.0% (67/1336) with a 1.4% reoperation rate. (19/1336). Morbidity and reoperation rates showed no statistically significant difference between the two groups in relation to number of repairs in group B. After a median 24-month clinical follow-up period (1-84 months) (follow-up rate 93.1%) 38 recurrences were observed in group A (0.9%) and 17 in group B (0.6%; 17/2672) (p = 0.2668). Median time off work was 14 days after unilateral (2-63 days) and 17 days after bilateral repair (3-100 days) (p = 0.1359). Pain levels (numerical analogue scale) and incidence of persistent inguinal and scrotal pain are not higher after bilateral repair. CONCLUSION: Compared to unilateral repair, bilateral simultaneous laparoscopic hernia repair (TAPP) is safe, comfortable for patients, and cost-effective, without increased morbidity or recurrence risk. Bilateral inguinal hernia is an ideal indication for endoscopic transabdominal repair.

Adolescent↗

PubMed2001

Laparoscopic transperitoneal hernia repair of incarcerated hernias: Is it feasible? Results of a prospective study.

BACKGROUND: Laparoscopic transperitoneal hernia repair (TAPP) has proved its efficiency in elective surgery. However, TAPP results with incarcerated hernias still are unknown. METHODS: Data from a prospective study were evaluated with regard to TAPP repair for both chronically and acutely incarcerated hernias. RESULTS: During a 6-year period, 220 incarcerated hernias were repaired (194 via TAPP). The median operation time for TAPP was 55 min. An accompanying resection therapy became necessary for only four of the emergency cases (11.1%) and two of the chronically incarcerated cases (1.3%) in the TAPP group. Postoperative morbidity was 2.8% in the emergency group and 3.8% in the chronically incarcerated group, which does not differ from the rate for TAPP used on reducible hernias. One recurrence was found 26 months after TAPP reconstruction (0.5%). CONCLUSION: Laparoscopic inguinal hernia repair (TAPP) represents an efficient therapeutic concept in the treatment of both chronically and acutely incarcerated inguinal hernias.

Feasibility Studies↗

PubMed2001

Characterization of sequence determinants within the carboxyl-terminal domain of chemokine receptor CCR5 that regulate signaling and receptor internalization.

The CC chemokine receptor CCR5 mediates chemotaxis of leukocytes and serves as a principal co-receptor for macrophage-tropic human immunodeficiency virus type 1. To identify determinants on the CCR5 carboxyl-terminal domain that regulate receptor signaling and internalization, we generated several CCR5 mutants, which were progressively shortened from the COOH terminus or had carboxyl-terminal serine, cysteine, or leucine residues substituted by alanine and expressed them in RBL-2H3 cells. Using fluorescence resonance energy transfer between beta-arrestin and CCR5 tagged with cyan and yellow variants of green fluorescent protein, we show that high affinity association of the two molecules in living cells requires intact carboxyl-terminal serine phosphorylation sites. Phosphorylation-deficient truncation or Ser/Ala replacement mutants of CCR5 mediated a sustained calcium response and enhanced granular enzyme release in RANTES-stimulated cells. Carboxyl-terminal serine residues are critically involved in CCR5 endocytosis and a dileucine motif, similar to that implicated in the regulation of CXCR2 and CXCR4, contributes to the internalization of CCR5 in a phosphorylation-independent manner. Despite their prominent role in receptor desensitization and internalization, beta-arrestins are dispensable for the CCR5-mediated stimulation of mitogen-activated protein kinase pathways in RBL-2H3 cells. We also show that CCR5 is palmitoylated on carboxyl-terminal cysteine residues. Inhibition of CCR5 palmitoylation by alanine mutagenesis of cysteines or treatment with a palmitate analogue inhibitor profoundly reduces phorbol 12-myristate 13-acetate- and RANTES-induced receptor phosphorylation, homologous desensitization, and internalization. Alanine mutagenesis of serine, cysteine, or leucine residues or the limited carboxyl-terminal truncation of CCR5 did not impair chemokine-stimulated migration of RBL-2H3 cells. Together these results indicate that post-translational modifications of carboxyl-terminal serine and cysteine residues have a significant impact on receptor deactivation and internalization.

Amino Acid Sequence↗

PubMed2001

Cytokeratin expression and epithelial differentiation in Warthin's tumour and its metaplastic (infarcted) variant.

AIMS: Warthin's tumour is characterized by a bilayered columnar epithelium. Transformation into metaplastic (infarcted) Warthin's tumour includes squamous metaplasia of the epithelium along with regressive changes in the stroma. Misinterpretation of metaplastic Warthin's tumour for malignancy is a serious diagnostic pitfall. This study assesses the utility of cytokeratin expression in Warthin's tumour and its metaplastic variant. METHODS AND RESULTS: Twenty-six cases of Warthin's tumour, among them eight metaplastic Warthin's tumours, were investigated employing immunohistochemistry. Both Warthin's tumour and its metaplastic variant regularly expressed cytokeratins (CK) 7, 8, 18, and 19. Staining results with antibodies to CK10, 10/13, 1/2/10/11, and 20 were negative in all specimens. Immunoreactivity for CK 5/14 and 17 was restricted to basal cells in Warthin's tumour, but involved basal as well as surface cells in metaplastic Warthin's tumour. CONCLUSIONS: Warthin's tumour and its metaplastic (infarcted) variant both express CK 7, 8, 18, and 19, which are typical for columnar differentiation. Cytokeratins typical of squamous differentiation are absent from Warthin's tumour and its metaplastic variant, irrespective of the squamous morphology of the epithelium in metaplastic Warthin's tumour. The expression of CK 5/14 and 17, which are typical of regenerative cells, is restricted to basal cells in Warthin's tumour, but is expressed also in surface cells in metaplastic Warthin's tumour.

Adenolymphoma↗

PubMed2001

Patterns of p21(waf1/cip1) expression in non-papillomatous nasal mucosa, endophytic sinonasal papillomas, and associated carcinomas.

AIMS: To clarify p21(waf1/cip1) expression in sinonasal lesions. METHODS: Archived surgical specimens from 38 patients were investigated by means of immunohistochemistry. p21(waf1/cip1) staining was evaluated in the different layers of the epithelium. In addition, human papillomavirus (HPV) infection and p53 protein overexpression were assessed and correlated with p21(waf1/cip1) expression. RESULTS: p21(waf1/cip1) staining was negative in non-papillomatous nasal mucosa. HPV infection and p53 protein overexpression were not seen. Sixteen of 20 inverted papillomas showed p21(waf1/cip1) expression. HPV infection was found in 16 cases and p53 protein overexpression was present in 13 specimens. Expression of p21(waf1/cip1) was restricted to surface cells in five cases, but involved basal/parabasal cells in 11 specimens. Immunoreactivity for p21(waf1/cip1) in basal/parabasal cells colocalised with p53 protein overexpression. Enhanced expression rates for p21(waf1/cip1) were seen in transitional and squamous epithelium compared with columnar epithelium. p21(waf1/cip1) expression involved only surface cells in cylindrical cell papillomas. HPV infection and p53 protein overexpression were detected in all specimens. One of five squamous cell carcinomas showed p21(waf1/cip1) expression. HPV infection was seen in two cases, and all carcinomas showed p53 protein overexpression. CONCLUSIONS: Expression of p21(waf1/cip1) is associated with terminal differentiation in surface cells in inverted papillomas and cylindrical cell papillomas, but not in non-papillomatous nasal mucosa. Overexpression of p53 protein colocalises with p21(waf1/cip1) expression in basal/parabasal cells in inverted papillomas but not in cylindrical cell papillomas. Expression of p21(waf1/cip1) in squamous cell carcinomas involves a subset of tumours with p53 protein overexpression.

Adolescent↗