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J Buchwald

Publications and source records attributed to J Buchwald.

At least 19 recordsLinked to original sources
PubMed1992

Well-differentiated thymic carcinoma. An organotypical low-grade carcinoma with relationship to cortical thymoma.

Based on a study of 26 cases, the well-differentiated thymic carcinoma is described as a distinct organotypical carcinoma of the thymus with low-grade malignancy. It is characterized by a predominance of epithelial cells with usually low mitotic rate, an epidermoid differentiation with slight to moderate cytological atypia, the constant presence of interepithelial immature cortical thymocytes, lobular growth, and formation of epithelial palisades around perivascular spaces. The tumor occurs at age 14 to 76 years in both sexes. An association with myasthenia gravis is found in 77% of the patients, and 83% of the tumors show invasion of adjacent organs or endothoracic metastasis at primary operation. This rate is higher than in cortical thymomas (47%) but lower than in other thymic carcinomas (92%). Two of 18 patients with follow-up died of tumor recurrence and pleural metastasis. Well-differentiated thymic carcinoma can be related to cortical thymoma by common morphological features and a similar immunophenotype of epithelial cells. It must be differentiated from the lymphocyte-depleted cortical thymomas after corticosteroid treatment and from the benign epithelial-rich medullary thymomas.

Adolescent↗
PubMed1992

[Current intra- and early postoperative results of transvenous pacemaker implantation].

UNLABELLED: Between 1986 and 1989 295 pacemaker (PM)-implantations were performed (mean age: 69.9 +/- 14.5 years; 54.9% male, 45.1% female). INDICATIONS: AV-Block II+III (36.6%), sick-sinus-syndrome (26.4%), bradyarrhythmia (18.0%). Concomitant disease: hypertension (40.6%), diabetes mellitus (19.3%), coronary artery disease (11.5%), malignant tumors (10.8%), renal failure (7.5%). We implanted in 72.9% VVI-PM, in 23.7% DDD-PM and in 3.4% AAI-PM. The median fluoroscopy-time as a measure for time of surgery was 6.2 minutes (DDD: 6.7; VVI: 5.4; AAI: 9.9). In 6.5% there were intraoperative complications: arrhythmias (3.4%), skeletal muscular stimulation (M.pect.; 1.4%), lead dislodgment (0.7%), missed puncture (A.subcl.; 0.7%). The early postoperative (14 days) complications rate was 9.5% (lead dislodgment 3.7%, development of high threshold 1.7%, bleeding 1.4%, bacteriaemia 1.0%, skeletal muscular stimulation 0.7%). The complication rate of AAI-PM (70.0%) was significantly higher compared to DDD-PM (29.8%; p less than 0.01) and VVI-PM (12.1%; p = 0.00025). In 17 patients (5.8%) reoperation was necessary (lead dislodgment n = 11, development of high threshold n = 3, arrhythmias n = 2, postoperative bleeding n = 1). The highest dislodgment rate was seen in atrial leads with active fixation (5.0%). In 2.6% of active fixation leads there was a development of high thresholds (passive fixation leads 0.5%). The selection of the PM-system to be implanted has to be considered in respect to the increased complication rate of DDD- and AAI-PM, especially in elderly patients.

Adult↗
PubMed1991

Special subtypes of pulmonary adenocarcinomas indicated by different tumor cell HLA-expression and stromal infiltrates. A light, electron microscopic and immunohistologic study.

A total of 31 human peripheral adenocarcinomas (AC) of the lung were subclassified by light and electron microscopy according to their phenotypic characteristics. The expression of HLA-A,B,C and HLA-DR on tumor cells, and the degree of subclassified mononuclear cell infiltration were determined using immunohistologic and morphometric methods. The study shows that pulmonary AC can be subdivided in two main types with different properties. The first type is characterized by mucin production comparable to that of bronchial goblet cells. These mucinous AC of type I show nearly no expression of HLA-DR; the tumor volume fraction with HLA-A,B,C expression is greatest in highly differentiated AC I, and decreases significantly with lower grades of differentiation. The AC of type II, possibly originating from the bronchioloalveolar transitional zone, show properties of Clara cells and of type II-pneumocytes by light and electron microscopy. These features include apically located electron-dense granules and lamellar bodies occurring often simultaneously. Both groups of HLA-antigens, HLA-A,B,C and HLA-DR, are homogeneously distributed in a similar phenotypic fashion to Clara cells and pneumocytes II of the normal lung. The significant differences in mononuclear cell infiltration between the two tumor types are possibly induced by the different HLA-DR expression, which have not been seen in AC from other sites. In AC II with homogeneous HLA-DR expression in the tumor epithelium, the numbers of tumor-infiltrating Langerhans cells, and T- and B-lymphocytes are significantly higher than in AC I, possibly indicating better host immunologic defense mechanisms against these tumors.

Adenocarcinoma↗
PubMed1991

[Perioperative complications in pacemaker surgeries].

In the years 1979 to 1985 (period I) 717 (102 per annum), in 1986 to 1989 (period II) 295 (73 per annum) pacemaker procedures had been performed at the cardiothoracic surgery division of Würzburg University. Indications for pacemaker therapy were in 35.4% vs. 36.6% (period I vs. period II) an atrioventricular block grade II or III, in 18.1% vs. 26.4% sick sinus syndrome, in 15.3% vs. 18.0% bradycardic rhythm disturbances, in 9.5% vs. 6.1% a sinuatrial block, in 6.5% vs. 2.4% a bradycardic sinus rhythm, in 12.4% vs. 3.7% others. While 41% of the procedures were performed under general anesthesia during the first period of observation, local anesthesia was predominant later on. Preferred venous access (79% vs. 74%) was the right cephalic vein followed by the subclavian vein (12% vs. 14%). The amount of the two chamber systems rose form 11% (period I) to 24% (period II). Intraoperative complications occurred in 2.5% vs. 5.8% and postoperative (within 14 days) complications occurred in 4% vs. 5.8%, respectively. No death was to be registered. The reasons for the increase of intra- and postoperative complications are discussed.

Aged↗
PubMed1991

[Treatment of iatrogenic esophageal perforation].

Between the years 1985 and 1989 11 patients with iatrogenic esophageal perforation were treated at the Department of Surgery at the University of Würzburg. 5 perforations were diagnosed within 24 hours, the others after 1 to 5 days. All patients received a non resective surgical treatment, consisting of excision of the perforated area, primary closure in single suture technique strictly extramucosal and drainage. In addition fibrin glue and a pleural wrap protected the suture. In 55% the postoperative course was completely inconspicuous. Only one patient with a recidive of a gastric cancer with lung and liver metastases, died 11 days after operation of a cervical perforation.

Esophageal Perforation↗
PubMed1990

Histocompatibility antigen expression in pulmonary carcinomas as indication of differentiation and of special subtypes.

In 70 human carcinomas of the lung the expression of histocompatibility antigens (HLA) was investigated by using monoclonal antibodies in frozen sections. The immunmoreactive tumor volume was determined morphometrically. The tumor types showed a different pattern of HLA expressions. In squamous cell carcinomas (SQC) and small cell carcinomas (SCC) the HLA-A,B,C expression varied in a great range from 0% to 100% of positive tumor volume. For the most part, HLA-DR was not demonstrable. In adenocarcinomas (AC) and large cell carcinomas two different populations were observed. One showed a pattern of HLA expression as seen in SQC. Electron microscopically these AC (type 1) (AC/1) were characterized by intracytoplasmic mucin granules indicating a phenotypical relationship to goblet cells. The other--nearly 50% of adenocarcinomas and one third of large cell carcinomas--expressed both HLA antigens homogeneously in the total tumor volume. Electron microscopically the characteristics of type II pneumocytes and Clara cells were seen in tumor cells of these AC (type II) (AC/II), consisting in lamellar bodies and apically located electron-dense granules. In SQC and AC/I a significant correlation was found between grades of differentiation and mitotic activity on the one side, and expression of HLA-A,B,C on the otrher. The loss of HLA-A,B,C expression seemed to be an indication of a lower grade of differentiation; the smalles expression of HLA-A,B,C occurred in SCC.

Adenocarcinoma↗
PubMed1989

[Arteriovenous lung fistula--diagnosis and surgical therapy].

Congenital pulmonary arteriovenous fistula is a rare condition and, for this reason, is repeatedly misinterpreted despite the typical complaints it gives rise to. On the basis of seven cases diagnosed and treated surgically by the present authors, including follow-up, the clinical picture is discussed in detail. The diagnosis of pulmonary arteriovenous fistula can be established on the basis of pulmonary antiography or, more simply, with the aid of digital subtraction angiography with representation of multiple fistulas and accurate localisation. Employing segmentectomy, it usually proves possible successfully to treat even multiple arteriovenous fistulas in the lung, and to achieve lasting freedom from symptoms and recurrent disease. Even if it is asymptomatic, pulmonary arteriovenous fistula should always be resected, since life-threatening ruptures with followed by bleeding into the parenchyma and haemothorax (as was observed in one of our patients) can occur.

Adult↗
PubMed1988

J. Russell Reynolds and the study of interictal symptoms in epilepsy.

Sir John Russell Reynolds (1828-1896) was a prominent English neurologist who was among the first to carefully study interictal behavior in patients with epilepsy. He challenged the prevailing dogma that severe mental illness was nearly always concomitant of epilepsy. Studying the cognitive and emotional functions of 62 patients with essential (idiopathic) epilepsy, he found that 39% of the patients were normal, 32% had only mild impairment of recent memory, and 29% had moderate to severe psychopathologic findings. His study of interictal behavior in epilepsy is one of the earliest attempts to avoid selection bias and represents an important contribution to the study of this problem.

England↗
PubMed1988

Epithelial thymus tumors--therapy and prognosis.

One hundred and two patients with epithelial thymoma (ET) and carcinoma have undergone surgical treatment since 1957. In this series thymomas were classified according to Masaoka's clinical staging criteria (encapsulated, invasive) and according to Müller-Hermelink's histological criteria of the resected specimens (medullary and cortical differentiation) and compared to clinical symptoms and survival rates (mean follow-up time 66.4 months). We found that it is not always possible to differentiate intraoperatively fibrous adhesions from infiltrations of the thymic capsule or to recognise thymus carcinoma as such macroscopically if they have not already infiltrated the organ's capsule. All ETs with cortical differentiation after thymectomy showed a malignant course; in contrary ETs with medullary differentiation we found without relapses of metastases. ETs with both histological types (hybrid typs) and cortical dominance took in only two out of 57 cases a malignant course though five of them showed an invasion into the capsule according to clinical staging criteria stage II. Therefore classifying ETs only into two categories, encapsulated and invasive, according to surgical and gross findings, seems to be not always possible and insufficient for the clinical assessment of the malignity and prognosis.

Adult↗
PubMed1986

Cat P300 present after primary auditory cortex ablation.

A long-latency (200-500 msec) endogenous potential with characteristics of the human P300 was recorded over 12 sessions in 4 adult cats. Principal components analysis with t tests showed that this potential was significantly larger in response to rare auditory stimuli than to the same stimuli presented frequently. The primary auditory cortex was ablated bilaterally. The preoperative tone-elicited conditioned eye blink response remained postoperatively. After 12 postoperative sessions, statistical analyses of these data demonstrated that the P300-like potential was still present. Thus, the primary auditory cortex is not necessary for generation of the P300-like response in cats.

Acoustic Stimulation↗
PubMed1985

Aging changes in the cat P300 mimic the human.

Long-latency endogenous responses with characteristics of the human P300 were recorded from young cats (1-3 years). Principal components analysis and paired t tests confirmed that responses within a 200-300 msec latency window were significantly larger to rate stimuli than to frequent stimuli. In contrast, a similar study of long-latency responses in old cats (more than 10 years) showed no significant difference between the 'rare' and 'frequent' responses. These data indicate that the P300 changes functionally with old age in the cat, as in the human, and that the cat provides an important model for P300 generator analysis in the aged as well as in the young brain.

Acoustic Stimulation↗
PubMed1979

The first pelvic examination: helping students cope with their emotional reactions.

The author has conducted seminars with small groups of medical students beginning their training on an obstetrics and gynecology service. Six characteristic responses of students to performing their first pelvic examination are described. Within the framework of the seminar discussion, an attempt is made to help the students cope with those reactions that could impair their ability to perform competent gynecological examinations.

Emotions↗
PubMed1977

[Etiology and diagnosis of thoracic kidney (author's transl)].

Intrathoracic mass lesions revealed on routine chest-x-rays may represent high renal ectopia. This is particularly true in cases of dorso-basal location and in the absence of symptoms. On a case herein reported the value of excretory urography as important diagnostic procedure is demonstrated. The significance of angiographic features for etiological classification will be discussed. A comprehensive review of the relevant literature is given.

Adult↗