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C Schmid

Publications and source records attributed to C Schmid.

At least 235 records · Page 13Linked to original sources
PubMed1994

Primary B-cell mucosa-associated lymphoid tissue lymphoma presenting as a solitary colorectal polyp.

We describe two patients with low-grade and one patient with mixed low- and high-grade B-cell lymphoma of mucosa associated lymphoid tissue (MALT) type arising in the large intestine. In each patient the lesion occurred as a single polyp. Two patients presented with rectal bleeding and in one the lesion was discovered incidentally. The bone marrow was uninvolved in all three cases but in the patient with mixed low- and high-grade lymphoma involvement of mesenteric lymph nodes and liver was found. CT scan revealed no lymphadenopathy or splenomegaly in any of the patients. Two patients remain well 9 and 24 months respectively after polypectomy whereas the patient with mixed low- and high-grade lymphoma died 7 days after hemicolectomy due to cardiac failure. These previously undescribed solitary polypoid MALT lymphomas can closely resemble both benign lymphoid polyposis of the colon and lymphomatous polyposis (mantle cell lymphoma). Because of their different behaviour accurate diagnosis of polypoid MALT lymphoma is important.

Aged↗
PubMed1994

Proliferation centres in B-cell malignant lymphoma, lymphocytic (B-CLL): an immunophenotypic study.

Proliferation centres, also known as pseudofollicles, are present in approximately 90% of lymphocytic lymphomas (B-CLL). They consist of loosely arranged larger cells that often contain prominent nucleoli. In contrast to true B-cell follicles, which may be found entrapped within the small lymphocytic infiltrate in sections of B-CLL, proliferation centres are said not to contain follicular dendritic cells, although their presence has been occasionally recorded. We have carried out an immunohistochemical study of proliferation centres from 30 lymph node specimens of known cases of B-CLL, classified according to the Kiel classification, in six of which fresh frozen in addition to paraffin embedded tissue was available. We have compared proliferation centres with the surrounding small lymphocytic infiltrate and reactive B-cell follicles with respect to the presence of follicular dendritic cells and their associated network of IgM and complement, the cell proliferation fraction, the concentration of T-cells and the expression of bcl-2 protein. Most proliferation centres contained a delicate follicular dendritic cell network which was associated with IgM and complement, and showed a higher proliferation fraction than the surrounding small lymphocytic infiltrate. The proliferation centres contained more T-cells than the surrounding infiltrate and showed decreased expression of bcl-2 protein. Entrapped reactive B-cell follicles contained a much denser network of follicular dendritic cells, associated with much stronger expression of IgM and complement, and exhibited a very high proliferation fraction; they contained many T-cells and expressed very little bcl-2 protein.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, CD↗
PubMed1994

Bone marrow lymphocyte subsets in myelodysplastic syndromes.

AIM: To examine lymphocyte subsets in patients with myelodysplastic syndromes (MDS); and to correlate immunohistological variables with prognosis. METHODS: Bone marrow trephine biopsy specimens from 65 patients with MDS were immunophenotyped using a panel of antibodies. A minimum of 1000 cells from representative areas of marrow sections were counted at light microscopy. The association between immunohistological variables and prognosis was assessed. RESULTS: Compared with normal control marrows (n = 23) no major abnormalities of T cells (CD3), T cell subsets (CD4, CD8, CD25, TCR gamma/delta) or natural killer cells (CD56, CD57) were seen in the 65 patients. In high risk MDS (RAEB, RAEB-t) 19% of the cases showed increased numbers of B lymphocytes compared with none in the low risk group (RA, RARS) (p < 0.0090). Only percentages of B cells above 3% significantly correlated with poor survival (p = 0.0121 for CD19, p = 0.046 for CD22). CONCLUSIONS: The deviations in T lymphocyte counts seen in peripheral blood and in bone marrow aspirates could not be verified in bone marrow biopsy specimens.

Adolescent↗
PubMed1994

Growth hormone and parathyroid hormone stimulate IGFBP-3 in rat osteoblasts.

Osteoblast-like cells prepared from calvaria of newborn rats produce insulin-like growth factor (IGF) I and several insulin-like growth factor binding proteins (IGFBPs) in vitro. Among the IGFBPs found in conditioned cell culture medium, IGFBP-3 is the most abundant. Intact IGFBP-3, as assessed by 125I-labeled IGF-II ligand blot analysis, is more abundant in culture media of cells exposed to growth hormone (GH) or to parathyroid hormone (PTH), both at 5 x 10(-9) mol/l, for 24 h. At the same time, concentrations of IGF-I are increased in media of cells exposed to PTH but not to GH, compared with hormone-free control cultures. IGFBP-3 mRNA is increased in osteoblasts exposed to PTH or to GH but not in response to 5 x 10(-9) mol/l IGF-I. PTH exerts a rapid (within 2 h) stimulatory effect on IGF-I and IGFBP-3 production, both at the message and peptide levels, whereas GH increases only IGFBP-3, both at the message and peptide levels (after 24 h). We conclude that IGF-I does not mediate increased IGFBP-3 production by rat osteoblasts in response to GH and PTH.

Animals↗
PubMed1994

Expression and regulation of insulin-like growth factor-I (IGF-I) and IGF-binding protein messenger ribonucleic acid levels in tissues of hypophysectomized rats infused with IGF-I and growth hormone.

The expression and regulation of insulin-like growth factor-I (IGF-I) and IGF-binding protein-2 (IGFBP-2), -3, -4, and -5 messages were studied in liver, kidney, spleen, thymus, heart, brain, skeletal muscle, testes, and epididymal (white) adipose tissue (WAT) from hypophysectomized rats infused with saline, recombinant human (rh) IGF-I, or rhGH and compared with tissue messenger RNA (mRNA) levels in age-matched normal rats. The IGF-I message was present in all of these tissues. It was most abundant in liver and WAT, but was barely detectable in kidney, brain, and thymus. GH dependence was most pronounced in liver, skeletal muscle, and WAT and less so in heart, testes, kidney, spleen, and thymus. The IGF-I message in brain was not influenced by hypophysectomy. IGF-I infusion induced a small increase in its own mRNA in skeletal muscle and WAT, whereas it decreased its own message in liver. IGFBPs were expressed in a tissue-specific manner; IGFBP-2 mRNA was most abundant in testes and hypophysectomized liver, IGFBP-3 mRNA was most abundant in spleen, kidney, WAT, and liver, IGFBP-4 mRNA was most abundant in liver, and IGFBP-5 mRNA was most abundant in kidney, WAT, and skeletal muscle. After hypophysectomy, significant decreases in IGFBP expression were observed in liver (except IGFBP-2), skeletal muscle, brain, WAT (except IGFBP-4), and testes (except IGFBP-2), in contrast to heart, kidney, spleen, and thymus. GH infusion did not affect IGFBP-2 mRNA levels in liver (in contrast to IGF-I infusion) or brain. Like GH, IGF-I normalized IGFBP-3 mRNA levels in liver, but, in contrast to GH, had no effect on IGFBP-5 mRNA in WAT. It was considerably less effective than GH in raising IGFBP-5 mRNA levels in skeletal muscle. Thus, GH infusion can exert different effects on IGF-I and IGFBP expression than infused rhIGF-I. Differences may be due to direct actions of GH at the tissue level, including auto/paracrine effects of locally produced IGF-I.

Animals↗
PubMed1994

Interactions of insulin-like growth factor I with dexamethasone on trabecular bone density and mineral metabolism in rats.

Glucocorticoid treatment causes osteoporosis and growth retardation in humans. Insulin-like growth factor I (IGF-I) stimulates differentiation and replication of cultured osteoblast-like cells and induces longitudinal bone growth in IGF-I-deficient rats. We investigated the influence of subcutaneously infused IGF-I on bone and mineral metabolism of male rats treated with a high dose of dexamethasone. Dexamethasone was added to the drinking water in a concentration of 1 mg/l. After 30 days of dexamethasone treatment, recombinant human IGF-I (300 micrograms/day) or solvent was infused sc by osmotic minipumps for 21 days while dexamethasone was continued. Age-matched untreated male rats served as healthy controls. Dexamethasone-treated rats lost weight. Their IGF-I levels were decreased to 36% of healthy controls. Infusion of IGF-I resulted in an increase in IGF-I serum levels (582% compared to healthy controls) and allowed some weight gain. Osteocalcin and calcitriol levels were markedly decreased in dexamethasone-treated rats and were not influenced significantly by IGF-I infusion. In contrast, IGF-I treatment restored the free calcitriol concentration (molar ratio of calcitriol to vitamin D-binding protein) towards normal. Furthermore, infusion of IGF-I partially corrected the dexamethasone-induced hyperinsulinemia. Histomorphometric analysis revealed no difference in vertebral trabecular bone density (i.e. growth-independent bone remodeling) between the three groups. In contrast, mean trabecular bone density in tibial metaphyses was increased markedly by dexamethasone, presumably due to osteoclast inhibition. Insulin-like growth factor I infusion did not significantly influence these structural metaphyseal bone parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMed1994

Histologic patterns of primary malignant tumors of the fallopian tube.

From 1978 through 1993 four patients underwent surgical treatment of primary fallopian tube rumors. Mean age was 62.5 years. A different histologic pattern was found in each cases: transitional, endometrioid, serous papillary and malignant mixed mesodermal tumor. Prognostic significance of histologic patterns is underlined together with grade and stage; all our cases were included in stage IA. Surgical treatment was, in all cases, hysterectomy with bilateral salpingo-oophorectomy; in two cases an adjunctive chemotherapy followed. A second look was performed in two cases. All patients are alive and free of disease with a follow-up varying from 15 to 84 months.

Aged↗
PubMed1994

[Microcystic adenoma of the pancreas. Immunohistochemical and ultrastructural study of 7 cases].

Microcystic cystadenoma of pancreas is a rare benign neoplasm with peculiar pathologic characteristics. It is more frequent in women and in elderly age. Macroscopically it is composed of a spongy, microcystic mass with a starry central fibrous core. Histologically serous cysts are lined by cuboidal or flattened epithelium without nuclear atypias and with PAS positive cytoplasms. A surgical conservative approach is the treatment of choice. Seven cases of microcystic cystoadenomas of the pancreas observed within ten years at Osp. San Carlo Borromeo-Milano and Osp. Santa Maria degli Angeli-Pordenone from 6 women and 1 man aged 54-87 years are described. The preoperative and intraoperative investigations that have been necessary for reaching its diagnosis are discussed.

Aged↗
PubMed1994

[Human subcutaneous dirofilariasis: 8 new cases in northern Italy].

Eight new cases of Human Dirofilariasis in people living in Northern Italy were recorded: 3 from the province of Asti and 2 from Alessandria (Piedmont), 1 from Corsico (Miland, Lombardy) and 2 from Ravenna (Emilia-Romagna). All the patients were adults, 42 to 66 years old, 4 men and 4 women. The localization of the nematode in all the cases was subcutaneous. Signs and symptoms were always mild and consisted in the growth of a 1 to 2 cm large nodule associated with occasional localized itching and oedema, sometimes with reddening. In one case, the sting of a non-specified winged insect was recorded in the anamnesis, in the same spot where the nodule developed. In another case, the nematode came out spontaneously from the lesion. The aetiological agent was always identified as Dirofilaria repens. These 8 new cases confirm the comparatively frequent presence of Human Dirofilariasis in regions of Northern Italy, namely in the Po Valley.

Adult↗
PubMed1994

Suppression of chronic lymphocytic leukaemia by megakaryocytic myelosis.

In a 77-year-old Caucasian female B-cell chronic lymphocytic leukaemia was diagnosed and classified as stage 1 according to the Rai classification. The disease remained stable and therefore no antileukaemic therapy had to be initiated. Four years after the initial diagnosis the patient developed hepatosplenomegaly, anaemia and leukopenia. Bone marrow biopsy revealed megakaryocytic myelosis supervening upon the pre-existing chronic lymphocytic leukaemia.

Aged↗
PubMed1994

[Heart arrest in acute pulmonary embolism. An anatomo-clinical study].

The Authors describe the modalities and mechanisms of cardiac arrest (CA) in the course of acute pulmonary embolism (PE). Clinical data refer to 39 CA episodes occurred in 28 patients with massive or submassive PE; autopsy data are from 26 of 28 patients of the same series. One-third of 39 CAs proved at least momentarily reversible; two-thirds were irreversible. Data analysis showed that most CA episodes, reversible or otherwise, seen in the course of PE were due to electromechanical dissociation (EMD). In fact, EMD was responsible for 12 of 13 reversible CAs and 22 of 26 irreversible arrests. EMD usually follows shock, but may occur unheralded. When EMD-induced CA is at least temporarily reversible, the heart rate is often normal or high and QRS complexes are narrow. In most cases the sudden rise of right ventricular afterload came on top of a pre-existing myocardial damage, for the most part of ischemic, sometimes necrotic, origin. In this series, therefore, it seems quite difficult to tell "primary" from "secondary" forms of EMD. External cardiac massage continued for as long as 40 minutes was associated in some cases with a bolus fibrinolytic infusion within minutes from occurrence of CA. Five of 7 patients so treated made a temporary recovery and two survived; at autopsy, none of the 5 patients who died showed any evidence of bleeding attributable to local injury.

Acute Disease↗
PubMed1993

Growth hormone, but not insulin-like growth factor I, induces a serum protease activity for insulin-like growth factor binding protein-3 in hypophysectomized rats in vivo.

Insulin-like growth factor binding proteins (IGFBPs) modulate IGF action. Proteolytic cleavage of IGFBPs yields lower molecular forms with reduced ability to bind IGFs, thereby increasing IGF bioavailability. In serum from normal adult rats, we found a proteolytic activity for IGFBP-3, presumably a cation-dependent serine protease. It is lacking in serum from hypophysectomized rats and restored by infusion of growth hormone (GH), but not IGF I. Thus, IGF I does not appear to mediate the GH effect on IGFBP-3 proteolysis. Rather, GH seems to modulate IGF action indirectly via alteration of IGFBP-3 structure.

Animals↗
PubMed1993

Breast conservation therapy for early stage breast carcinoma with outstanding 10-year locoregional control rates: a case for aggressive therapy to the tumor bearing quadrant.

PURPOSE: Between 1982 and 1988 233 American Joint Committee on Cancer Stage I and II invasive breast carcinomas were prospectively treated in 225 women with conservative tumor excision, careful assessment of histopathological margins, and dose-adjusted irradiation to maximum doses of 70 Gy to the tumor bearing quadrant of the breast. METHODS AND MATERIALS: The pathological stages at presentation were T1N0 and T1N1 in 57% and 13% and T2N0 and T2N1 in 19% and 10% of the patients, respectively. All patients were irradiated according to a policy that, beyond the 50 Gy to the whole breast and draining lymphatics, the tumor-bearing quadrant was boosted in adjustment to the histopathological margin. Normal tissue margins of < 2 mm were considered positive, margins 2-5 mm close, and margins > 5 mm negative and were boosted with 20, 15, and 10 Gy, respectively. Patients in whom the margin could not be assessed were re-excised or boosted to 20 Gy. Re-excisions with no residual carcinoma were not boosted. Most patients boosted to 20 Gy to the tumor-bearing quadrant received interstitial 192-Ir implantations. RESULTS: The actuarial local control rates in the treated breast were 97.5% at 10 years with three recurrences having occurred at a median of 4.5 years after completion of radiotherapy. An additional two patients failed regionally outside the irradiation portals. The overall and disease-free survival of the whole group is 87.5% and 77%, respectively. CONCLUSION: The approach to breast conservation therapy followed in this study has resulted in outstanding local control rates and suggests that there may be a subset of patients that could be irradiated to the tumor bearing quadrant only.

Adult↗
PubMed1993

Nasopharyngeal angiofibroma: an immunohistochemical study of 32 cases.

Thirty-two cases of nasopharyngeal angiofibroma, including 2 recurrences, all of which had been excised from males between 7 and 25 years, were subjected to systematic immunohistochemical study. Most of the tumour vessels, which lacked elastic laminae, were characterized by vascular walls of irregular thickness and variable muscle content. In places endothelial cells were only separated from the stroma by a single attenuated layer of contractile cells, whereas elsewhere the same vessel walls showed pad-like thickenings of their muscle coat. All cells of the vessel walls showed immunoreactivity for vimentin and smooth muscle actin, whereas desmin-positive cells were present only in small numbers in some vessels, generally those with thicker muscle coats. The stromal cells were decorated by vimentin antibodies only; however, in some more fibrotic hyaline areas the stromal cells displayed also reactivity for smooth muscle actin. In most cases S-100 protein-staining disclosed many nerves, and this accentuated their parital distortion by tumour tissue. Our findings provide an extended insight to the morphology of angiofibromas at this site, particularly highlighting the irregularity of their vascular walls, which, taken together with the lack of elastic laminae and elastic stromal fibres, can be held responsible for the typical pronounced tendency for haemorrhage in these lesions.

Adolescent↗
PubMed1993

Synovial metaplasia of the skin.

We present two female patients, aged 15 and 45 years, with synovial metaplasia of the skin. Both lesions, localized in the knee and hand respectively, arose after preceding local trauma. Case 1 had intradermal irregular cystic spaces in the adjacent myxoid stroma of which large polygonal eosinophilic cells were found. In contrast, case 2 was characterized by a longitudinal space within the lower dermis and subcutis which was lined by a membrane similar to hyperplastic synovium. The cells of the membrane showed an eosinophilic spindle shaped cytoplasm with processes towards the lumen. In both cases the eosinophilic cells, strongly suggestive of fibroblasts, showed staining for vimentin only, whereas no reactivity could be obtained with antibodies to actin, desmin, S-100 protein, Factor VIII related antigen, cytokeratin, epithelial membrane antigen, carcinoembryonic antigen and CD 68. The absence of CD 68 positivity differs from that seen in normal and hyperplastic synovium. Delayed wound healing around a nidus seems the most likely cause of the change.

Adolescent↗
PubMed1993

Involucrin expression in breast carcinomas: an immunohistochemical study.

The expression of involucrin, a structural component of the envelope of mature squamous epithelium, was studied in 166 paraffin-embedded breast carcinomas. In 41 cases (24.7%) involucrin-positive, light microscopically non squamous tumour cells were detected. The number of involucrin-positive tumour cells varied considerably from case to case. For further characterization, involucrin-positive cases were studied using monoclonal antibodies to various cytokeratins (PKK1, EAB 903, EAB 904) and, in selected cases, double immunostaining with antibodies to cytokeratins and involucrin were performed. Coexpression of involucrin and cytokeratins demonstrated by PKK1 was seen in all tumour cells, whereas coexpression of involucrin and cytokeratins detected by EAB 904 was only seen in single and scattered cells in a few cases. Cytokeratins detected by EAB 903 were not coexpressed with involucrin in our cases. Our results indicate heterogeneity of cytokeratins in breast carcinomas and suggest a dissociation in the regulation of involucrin and cytokeratin expression.

Breast Neoplasms↗
PubMed1993

Hypofractionation in retinoblastoma: an increased risk of retinopathy.

Forty-four eyes in 38 children were treated between 1963 and 1991 by external radiotherapy for retinoblastoma. Treatment modalities varied widely during this period; in addition to radiotherapy there was chemotherapy (16/44), photocoagulation (14/44), and laser therapy or cryotherapy (14/44). Treatment technique and dose fractionation also varied widely; lateral beam technique (39/44) versus anterior or anterior/lateral beam; doses per fraction ranged from 1 to 4.5 Gy, total doses from 30 to 61.5 Gy, and overall times from 22 to 49 days. Patients were followed at 3-month intervals, and actuarial survival at 10 years was 88%, with 62% local control. Ten eyes showed clinical evidence of retinopathy. A multivariate analysis of factors associated with increased risk of retinopathy was carried out using the Cox proportional hazards model and the mixture model of Farewell. The estimated latent time was 17 months (95% confidence interval, 14-20 months). The only factors found to be significantly associated with retinopathy were total dose multiplied by dose per fraction, or total dose normalized to the equivalent total dose in 2-Gy fractions as estimated from the LQ model, and these gave equivalent descriptions. There were trends (not significant) for increased risk of retinopathy when treatments included chemotherapy or photocoagulation, and for decreased risk (also not significant) when cryotherapy was used in conjunction with radiotherapy. No significance could be attached to any of the following: number of sites per eye, Reese-Ellsworth stage, and family history. We conclude that hypofractionation carries a significant risk for retinopathy in the treatment of retinoblastoma.

Child, Preschool↗