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J Pahnke

Publications and source records attributed to J Pahnke.

27 records · Page 2Linked to original sources
PubMed1996

[Analysis of cervical lymph node metastasis of oropharyngeal carcinoma in relation to extent of the primary tumor].

PURPOSE: To assess the incidence and patterns of cervical lymph node involvement according to the location and the relation of the primary tumour to the parapharyngeal fasciae, compartments and tissues arising from different branchial arches. PATIENTS AND METHODS: The findings of clinical and CT examinations of 143 patients with histological evidence of oropharyngeal carcinoma were evaluated retrospectively. Local tumour spread, relation of the primary to the parapharyngeal fasciae, compartments and to the borders of tissues arising from different branchial arches were analysed and related to cervical lymph node involvement. RESULTS: Lymph drainage of the oropharynx and neighbouring neck regions is determined by the embryological development of the branchial arches and somites. Oropharyngeal carcinomas are tumours arising from tissues of the 2nd and 3rd branchial arches. The lymph of these tissues is collected by the vessels of the jugular neck node chains. If tumour invades tissues arising from the 1st branchial arch (structures of the oral cavity and floor of the mouth) tumour spreads into the ipsilateral lymphatic vessels arising from the 1st branchial arch and the submaxillary lymph nodes. If tumor invades tissues arising from occipital and cervical somites (posterior wall of the nasopharynx, retropharyngeal compartment and recessus submuscularis) metastases in the retropharyngeal and spinal-accessorial lymph nodes may appear. Regarding the tumour invasion of the subdistricts of the oropharynx totally different tumours were found. Tumour invasion of neighbouring structures was documented for the nasopharynx in 15%, for oral cavity and the floor of the mouth in 34%, the larynx in 24% and the hypopharynx in 22% of the cases. From these different patterns of local tumour spread different patterns of lymph node involvement resulted. Nodal involvement was found in 71%. In all these cases metastases in the ipsilateral upper jugular lymph nodes were present. The frequency of metastases in the jugular lymph node chains decreased in cranio-caudad direction (upper jugular group 100%, middle 18%, lower jugular group 5%). The frequency of bilateral jugular lymph node involvement (25%) increased in the some measure as the tumour approached the midline or crossed it. CONCLUSIONS: Knowledge of regular patterns of spread of oropharyngeal carcinoma is important for treatment procedures, especially for 3-dimensional radiotherapy.

Adult↗
PubMed1996

[Systematic analysis of cervical lymph node metastasis of larynx and hypopharynx carcinomas--a clinical computerized tomography study with special reference to extension of the primary tumor].

PURPOSE: To assess the incidence and patterns of cervical lymph node metastases in laryngeal and hypopharyngeal carcinomas according to the location, extension, and relation of the primary tumor to the parapharyngeal compartments and tissues arising from different embryological structures as branchial arches and somites. PATIENTS AND METHODS: The findings of clinical and CT examinations of 230 patients with histological evidence of laryngeal and hypopharyngeal carcinoma (44 T1-, 33 T2-, 41 T3-, 112 T4-carcinomas with lymph node involvement in 116 cases) were evaluated retrospectively. Local tumor spread and relation of the primary to the parapharyngeal compartments and to tissues arising from different embryological structures such as branchial arches and somites were analysed and related to cervical lymph node involvement. RESULTS: The pattern of cervical lymph node involvement depends upon location and extension of the primary tumor in the adjacent tissues of the larynx and hypopharynx. The density of the lymphatic vessels in these areas determines the likelihood of lymph node involvement. The frequency of NO cases in carcinomas strictly located in the vocal cord (n = 31) was 100%; in the glottic-supraglottic, supraglottic, and transglottic cancer (n = 106) 85%; in larynx-hypopharynx carcinomas (n = 54) 26%; in hypopharynx carcinomas (n = 12) 17%; and in larynx-hypo-oropharynx carcinomas (n = 46) 9%. Tumors in tissues arising from branchial arches 4, 5, and 6 are glottic-supraglottic, transglottic laryngeal, and laryngeal-hypopharyngeal carcinomas. Metastases of these tumors were frequently found in the jugular lymph node chains, particularly if the developed tissue of the "primitive glottis" was invaded by the primary. Upper jugular nodes ipsilateral to a supraglottic or hypopharyngeal primary were usually involved. The frequency of metastases in the jugular lymph node chains decreased in craniocaudal direction. If the tumor invaded the posterior wall of the hypopharynx or tissues.

Adult↗
PubMed1996

Noncoding sequences from the slowly evolving chloroplast inverted repeat in addition to rbcL data do not support gnetalean affinities of angiosperms.

We developed PCR primers against highly conserved regions of the rRNA operon located within the inverted repeat of the chloroplast genome and used these to amplify the region spanning from the 3' terminus of the 23S rRNA gene to the 5' terminus of the 5S rRNA gene. The sequence of this roughly 500-bp region, which includes the 4.5S rRNA gene and two chloroplast intergenic transcribed spacer regions (cpITS2 and cpITS3), was determined from 20 angiosperms, 7 gymnosperms, and 16 ferns (21,700 bp). Sequences for the large subunit of ribulose bisphosphate carboxylase/oxygenase (rbcL) from the same or confamilial genera were analyzed in both separate and combined data sets. Due to the low substitution rate in the inverted repeat region, noncoding sequences in the cpITS region are not saturated with substitutions, in contrast to synonymous sites in rbcL, which are shown to evolve roughly six times faster than noncoding cpITS sequences. Several length polymorphisms with very clear phylogenetic distributions were detected in the data set. Results of phylogenetic analyses provide very strong bootstrap support for monophyly of both spermatophytes and angiosperms. No support for a sister group relationship between Gnetales and angiosperms in either cpITS or rbcL data was found. Rather, weak bootstrap support for monophyly of gymnosperms studied and for a basal position for the aquatic angiosperm Nymphaea among angiosperms studied was observed. Noncoding sequences from the inverted repeat region of chloroplast DNA appear suitable for study of land plant evolution.

Base Sequence↗
PubMed1995

High-resolution magnetic resonance imaging of the endolymphatic duct and sac.

An anatomical study was carried out to determine the extent to which magnetic resonance imaging (MRI) could delineate inner ear structures. Anatomical preparations of human petrous temporal bone were examined and compared with the results of MRI in 20 healthy subjects to see whether the structures of the inner ear could be visualized. Imaging of the subjects was carried out in a 1.0-T MRI scanner (Siemens Magnetom Impact). Two strongly T2*-weighted sequences were used: a 3D-PSIF sequence and a 3D-CISS sequence. The 3D data sets were postprocessed using a Maximum Intensity Projection (MIP) program. Our investigations show that it is possible to obtain accurate visualization of structures with a diameter of under 1 mm. In all 20 subjects it was possible to identify both the endolymphatic duct and the endolymphatic sac.

Adult↗
PubMed1994

[Systemic fungal infections in hematologic neoplasms. An autopsy study of 1,053 patients].

BACKGROUND: Mycoses are common complications of haematological neoplasias. For successful antimycotic treatment, a knowledge of preferential underlying disease, frequency, species and site of the mycosis is of importance. PATIENTS AND METHODS: Postmortem material comprising clinical data, autopsy protocols and histological sections obtained between 1976 and 1990 from 1,053 patients with leukaemia and malignant lymphomas following antineoplastic therapy was analysed retrospectively. RESULTS: Autopsy revealed systemic mycoses in 184 patients (17.5%). Between 1976 and 1990, the incidence of fungal infections increased from 12% to 30%, most being found in acute leukaemia (24%). Myeloproliferative syndrome (18%), non-Hodgkin's lymphomas (16%), Hodgkin's disease (10%) and plasmocytoma (2.5%) were less frequently associated with mycoses. With no preference for any particular malignancy in evidence, aspergillosis predominated at histology (85 cases), while candidosis occurred in 75 cases. A combination of two mycoses (aspergillosis and candidosis) (14 patients), zygomycosis (eight patients) and cryptococcosis (two patients) were much less common. While aspergillosis caused mostly pulmonary (81 cases) and cerebral (18 cases) infections, candidosis most frequently affected the GI tract (83 cases). The fungal infection was regarded as the main cause of death in some 76% of the cases. An analysis of bone marrow of patients with mycosis (184 cases) revealed a predominance of hypoplasia (54%) over tumour infiltration (34%) and normal bone marrow (12%). In malignancies with no mycoses (869 cases) in contrast, hypoplasia was significantly less common (19%) than infiltration (59%) or normal bone marrow (22%) (p < 0.001). CONCLUSION: The incidence of mycoses in haematological neoplasias in our post mortem series has continued to increase. Bone marrow hypoplasia in particular predisposes to fungal infection. The lungs are the organs of predilection, and aspergillosis is likely to be the infection presenting.

Autopsy↗
PubMed1988

[The sphenoid sinus, clinical anatomy of approaches to the pituitary region].

Sphenoidal sinus, clinical anatomy: mean values of measurements and research. The ostium of the sinus is situated 4.8 mm paramedian, 4 mm behind the sphenoid sinus with a width of 13.8 mm. Conchal types were estimated in 3%, presellar types in 23.8%, sellar types in 28.6% and postsellar sinuses in 47.6%. The ostium of the sphenoid sinus has a distance to the anterior wall of the Sella turcica mean = 14.6 mm. Included are length values of the sinus, the prominences in the side wall, and the recessus. Our results are discussed with the results of earlier researchers.

Female↗
PubMedDate not supplied

Activated microglia do not mediate the early deposition of Abeta in carriers of the apolipoprotein Eepsilon4 allele.

Activated microglia are a prominent component of the senile plaques in end-stage Alzheimer's disease, but whether microglia contribute to the initiation of the lesions remains unknown. In a previous postmortem study of non-demented elderly cases, we found that amyloidogenesis is advanced by at least 10 years in carriers of the apoEepsilon4 allele. To determine whether microglia are involved in the initial stages of beta-amyloid pathogenesis and whether apoE genotype influences microglial activation, we quantified HLA-DR-immunoreactive microglia in the medial temporal lobe of 229 non-demented humans of various APOE genotypes who had died between 50 and 91 years of age. Our results show that the number of HLA-DR-immunoreactive microglia increases with advancing age in both the gray matter and the white matter. In contrast to amyloid plaques and neurofibrillary tangles, there is no significant correlation between apoE genotype and density of microglia, although apoEepsilon4 homozygotes tended to have more microglia than did other apoE groups. In sections double-immunostained for Abeta and activated microglia, activated microglia were associated with dense-cored plaques but not with diffuse plaques, suggesting that microglial activation is a relatively late event in the genesis of beta-amyloid. Activation of microglia thus appears not to be the initial impetus for Abeta-deposition in the elderly.

Age Factors↗
PubMedDate not supplied

Expression of multidrug transporters in dysembryoplastic neuroepithelial tumors causing intractable epilepsy.

OBJECTIVE: Dysembryoplastic neuroepithelial tumors (DNT) are relatively benign brain lesions that often cause medically intractable epilepsy. There is mounting evidence that multidrug transporters such as P-glycoprotein (P-gp) or multidrug resistance-associated proteins (MRP) play an important role in the development of resistance to antiepileptic drugs (AED). MATERIAL AND METHODS: In the present study, we examined the expression of several multidrug transporters in 14 cases of DNT. The peritumoral brain tissue as well as 9 cases of arteriovenous malformations (AVM) served as controls. P-gp, MRP2, MRP5 and breast cancer resistance protein (BCRP) expression was evaluated qualitatively and quantitatively using immunohistochemistry. RESULTS: All transporters were overexpressed quantitatively in DNT, but each revealed a different labeling pattern. P-gp and BCRP were predominantly located in the endothelium of brain vessels. MRP5 was detected primarily in endothelial cells, but notably also in neurons. The expression of P-gp, MRP2 and MRP5 was low in AVM, whereas BCRP demonstrated strong staining. Examination of MDR1 gene polymorphisms revealed no correlation with P-gp expression whereas the MRP2 exon 10 G1249A polymorphism was associated with different MRP2 labelling. CONCLUSIONS: Our results show that multidrug transporters are overexpressed in DNT. This finding supports the view that several of these transport proteins may play an important role in the mechanisms of drug resistance in epileptic brain tissue.

Adolescent↗