Maxillary odontogenic carcinoma with distant metastasis to axillary skin, brain, and lung: case report

We present a case of odontogenic carcinoma with ghost-cell keratinization of the right maxilla, with a history of 23 years after initial treatment. Within this period, multiple local recurrence, as well as metastasis to axilla, brain, and lung, was noted. Several attempts at resection of the primary lesion were unsuccessful at achieving local control, even when supplemented with chemotherapy and radiotherapy. Metastatic tumors were studied histologically, and their morphology coincided with that of the primary tumor. The medical history of the patient and pathologic findings of the tumor are reviewed.

Role of the pericytes of intra-acinar pulmonary artery in the structural remodeling of pulmonary vessels

Whether or not the pericytes exist in the intra-acinar pulmonary arteries and their normal structure and morphological changes during development of the structural remodeling of pulmonary vessels were observed using a pulmonary hypertension model in rats induced by monocrotaline injection. The results showed that the pericytes in the peripheral pulmonary vessels proliferated and transformed into smooth muscle cells during development of pulmonary hypertension, and at the same time, the pericytes could synthesize and secrete extracellular matrix including collagen, suggesting that the pericytes play an important role in the development of pulmonary hypertension and structural remodeling of the pulmonary vessels.

Carcinosarcoma of the lung: an analysis of 6 operated cases

BACKGROUND

Carcinosarcoma of the lung is a rare malignant pulmonary neoplasm, and constitutes 0.1% to 0.3% of all lung tumors. Typically, these tumor have both carcinomatous and sarcomatous components with a poor prognosis due to late diagnosis and early metastases.

METHODS

From July 1980 to December 1993, six patients with pulmonary carcinosarcoma who underwent surgical treatment were studied. None of them had accurate tissue diagnosis before operation except one case with peripheral variant carcinosarcoma who was diagnosed by percutaneous transthoracic fine needle biopsy under sonographic guidance. All of our patients had a huge peripheral lung tumor 3.8 to 10 cm in diameter. Pneumonectomy was done in two patients, and lobectomy in three. The other patient had unresectable tumor.

RESULTS

The histopathological components in carcinoma were epidermoid carcinoma in and adenocarcinoma in 3. Differentiation of sarcomatous lesions included spindle cell sarcoma in 3, fibrosarcoma in 2 and undifferentiated mesenchymal sarcoma in one patient. In the resectable group, 1 was at stage II and 4 were at stage IIIa. None of the patients survived more than 2 years due to distant metastasis and cachexia. The mean survival was 140 days.

CONCLUSIONS

The carcinomatous portion tends to metastasize to regional lymph nodes whereas the sarcomatous part gives rise to systemic dissemination. Due to early systemic dissemination and poor prognosis, combination of extensive surgical intervention resection with aggressive postoperative chemotherapy and radiotherapy might be a reasonable consideration to improve survival in primary pulmonary carcinosarcoma.

Determination of mitomycin C in human aqueous humor and serum by high-performance liquid chromatography

Mitomycin C (MMC) is used in the treatment of disseminated adenocarcinoma of the stomach and pancreas and is used in ophthalmology as adjunctive therapy in trabeculectomy. Since only small volumes of aqueous humor are available for analysis, a sensitive method requiring limited sample preparation was developed. An internal standard, 4-aminoacetophenone, was added to aqueous humor specimens, and the solution was directly injected into the high-performance liquid chromatographic (HPLC) column. The use of a short 50-mm C18 reversed-phase column gave adequate resolution of peaks with improved sensitivity. The method was applicable for determination of MMC in serum, although solid-phase extraction for sample clean-up was required prior to injection into the HPLC column, and analytical columns of 150-250 mm were necessary for adequate resolution of peaks. The method has been validated and is linear from 6.25 to 50 ng/ml in aqueous humor and from 10 to 500 ng/ml in serum.

The helix-loop-helix proteins (salivary-specific cAMP response element-binding proteins) can modulate cAMP-inducible RP4 gene expression in salivary cells

Salivary-specific and cAMP-inducible expression of the rat proline-rich protein gene RP4 is dependent on a 28-base pair sequence of a salivary-specific cAMP response element (SCRE) (Lin, H. H., and Ann, D. K. (1992) Gene Expression 2, 365-377). To unravel its trans-acting factor(s), we used double-stranded oligoprobes corresponding to the SCRE to screen a randomly primed lambda gt11 cDNA expression library made from RNA of rat salivary cells. In this report, we describe the cDNA cloning of these helix-loop-helix SCRE-binding proteins (SCBPs) and demonstrate that there are at least three isoforms in salivary cells, namely SCBP alpha, SCBP beta, and SCBP gamma. RNA polymerase chain reaction and sequence analyses further confirmed the existence of these three different SCBP isoforms, which code for putative proteins of 707, 706, and 682 amino acids, respectively. Expression of the cloned SCBP cDNAs in salivary cells stimulates the expression of a cotransfected reporter construct containing multicopies of the SCRE cloned upstream of the thymidine kinase promoter and the chloramphenicol acetyltransferase structural gene. This stimulation is much more pronounced in transfections in which SCBP alpha and SCBP beta are cotransfected than when they are transfected individually. Furthermore, when low concentrations of SCBP alpha and SCBP beta are cotransfected with the SCRE reporter gene, coexpression of the catalytic subunit of protein kinase A is required to efficiently activate the expression of the reporter gene. These results strongly suggest that the observed stimulation of the SCRE is achieved through the coordinated expression of the SCBP alpha, SCBP beta, and protein kinase A activities, perhaps via a direct association of the two SCBPs and their phosphorylation by protein kinase A. We conclude that the isolated SCBP alpha and SCBP beta cDNAs encode transcription activators that participate in the control of the inducible RP4 gene expression in salivary cells.

Habenulo-interpeduncular descending pathways and their relationship to enkephalin- and somatostatin-immunoreactive neurons in the interpeduncular nucleus of human fetuses

The interpeduncular nucleus of six human fetuses aged 15 (one specimen), 26 (one specimen), 38 (one specimen) and 40 (three specimens) gestation weeks was studied by immunohistochemistry for enkephalin and somatostatin localization and immunohistochemistry coupled with silver staining. Enkephalin-positive and somatostatin-positive cells were detected, the former initially at 15 weeks gestation and the latter at 26 weeks gestation. They appeared to receive long afferents from the habenular region and projected short efferents to adjacent cells devoid of enkephalin and somatostatin positivity. We postulate that these enkephalin- and somatostatin-positive neurons function as modulatory interneurons in the habenulo-interpeduncular and related pathways.

Nucleotide sequence of the 5' region of the human platelet-derived growth factor A-chain gene

We have isolated and characterized genomic clones of the 5' region of the human PDGF A-chain gene. The putative "TATAA" box was identified 876 bp upstream of the translation initiation site. A significant number of potential regulatory elements were identified in DNA sequences upstream of the "TATAA" box and were also found within the introns sequenced. The DNA sequence results differ significantly from those reported for the PDGF B-chain gene, suggesting a basis for the expression of the PDGF A-chain gene and the B-chain gene under very different conditions.

Pulmonary carcinosarcoma: diagnostic approach by fine needle aspiration biopsy

Carcinosarcoma of the lung is an exceedingly uncommon malignancy, possessing both malignant epithelial and mesenchymal elements. There are less than 100 cases reported in the English literature to date. Most of them were diagnosed by autopsy and surgery. Now we present a detailed report of a case with peripheral variant carcinosarcoma diagnosed by percutaneous needle biopsy under sonographic guidance. The clinical, pathologic and immunohistochemical hallmarks of this unique tumor are also reviewed.

Monocrotaline-induced structural remodeling of the intra-acinar pulmonary arteries and pulmonary hypertension

The monocrotaline-induced structural changes of small pulmonary arteries in rat and their relationship with pulmonary hypertension and right ventricular hypertrophy were observed by determining the right ventricular systolic pressure, and by light and electron microscope and morphometry. One to 38 days after last injection of monocrotaline (MCT), a medial thickening and lumen marrowing of the circular muscular arteries (CMA), accompanying terminal (TB) and respiratory bronchioles (RB), were found. And there after the lumen of CMA, accompanying TB, became dilated, and its medial thickness (MT) decreased, whereas the histopathologic changes of the partially muscular arteries (FMA), accompanying RB, became severe, their MT increased continuously, and finally reached the peak value on Day 50. At the first day after last MCT treatment, inflammation and muscularization were found in PMA and nonmuscular arteries (NMA), and became more severe with the cause of disease. Therefore, the intra-acinar pulmonary arteries, both CMA and PMA, increased in number while the NMA decreased in number significantly because of the structural remodeling. Four days after MCT treatment, the right ventricular systolic pressure began to rise, and reached its peak value on Day 50. Eight days after MCT injection, right ventricular hypertrophy developed, and became most significant from Day 23 to Day 30. The results suggest that structural remodeling, i.e. muscularization, of intra-acinar pulmonary arteries plays an important role in the development of pulmonary hypertension and right ventricular hypertrophy.

[Radiology of diffuse panbronchiolitis: experience in VGH-Taipei]

Eleven cases of diffuse panbronchiolitis (DPB) were reported. According to plain chest film (10 cases) and high-resolution computed tomography (HRCT) (11 cases) findings, all were grouped as x-ray type B or CT type II advanced stage. Among them, 4 cases were grouped between CT type II-III; 3, CT type III-IV. All 11 patients had history of chronic paranasal sinusitis (CPS). Three patients had HLA typing. 1 had positive HLA Bw54; 3, HLA Cw1. We suggested patient with CPS, positive HLA Bw54 and Cw1 typing and clinically suspected DPB, radiological study including HRCT should be done.

Anomalous systemic arterial supply to normal basilar segments of the lower lobe of the left lung

A 38-year-old man with an anomalous systemic arterial supply from the descending thoracic aorta to the normal basilar segments of the left lower lobe experienced symptoms of progressive exertional dyspnea. Although the pulmonary parenchyma was normal, there was no pulmonary arterial supply to the basilar segments of the left lower lobe. Left lower lobectomy was performed because of worsening left-to-left shunt. Aortography and pulmonary arteriography form the cornerstone for diagnosis, but a less invasive diagnostic method with less patient suffering is high-resolution computed tomography, which might replace bronchography for accurate evaluation of the distribution and patency of the bronchial tree and delineation of the characteristic "Medusa's hair"-like anomalous vascular supply penetrating into the nearly normal pulmonary parenchyma.

The preventive effect of radix Salciae miltiorrhizae on monocrotaline-induced pulmonary hypertension in rats

The preventive effect of Radix Salciae Miltiorrhizae (RSM) on pulmonary hypertension (PHT) and right ventricular hypertrophy (RVH) induced by monocrotaline (MCT) in rats was observed with the methods of measuring the right ventricular systolic pressure (PVSP), the ratio of the right ventricle to the left ventricle plus interventricular septum RV/(LV+S) and the pulmonary small artery morphological analysis. The results show that RSM can reduce the PHT, and prevent the RVH and the increase of the medial thickness of pulmonary small arteries. It can also prevent the endothelial cell injury produced by MCT. The pharmacological effects of RSM on pulmonary circulation were also discussed.

Enhancement of erythropoiesis by recombinant human erythropoietin in low birth weight infants: a pilot study

We randomly assigned eight concurrently symptom-free premature infants (birth weight less than or equal to 1250 gm) at high risk of requiring erythrocyte transfusions for anemia of prematurity to 6 weeks of intensive treatment with either subcutaneous recombinant human erythropoietin (r-HuEPO group) or a placebo (control group). Treatment with r-HuEPO was initiated at a dose of 100 units/kg per day 5 days a week, and was increased to 200 units/kg per day after 2 or 3 weeks if target reticulocyte counts were not achieved. All patients were given supplemental oral iron therapy at a dose of 6 mg/kg per day, as tolerated. Mean reticulocyte counts in r-HuEPO-treated and control infants were 64,600 versus 67,500 cells/mm3 at entry; were 245,600 versus 78,000 cells/mm3 after 1 week; and averaged 262,600 versus 136,400 cells/mm3 during the study. Mean reticulocyte counts in r-HuEPO-treated infants were 251,200 cells/mm3 during the week when r-HuEPO, 100 units/kg per day, was given, and were 269,500 cells/mm3 after the dose was increased to 200 units/kg per day. Mean hematocrit values at entry were 33.4% in babies who received r-HuEPO versus 33.6% in the control subjects, and were 31.4% in r-HuEPO-treated and 25.2% in the control subjects at the end of treatment. One r-HuEPO-treated and three control babies received transfusions during the study; the total volume of blood given was 17 ml in the r-HuEPO group and 101 ml in the control subjects. The percentage of hemoglobin F increased in infants not given transfusions. We conclude that r-HuEPO stimulates endogenous erythropoiesis in small premature babies who are receiving supplemental oral iron therapy. A controlled multicenter trial has been undertaken to confirm these promising preliminary observations.

Aspergillosis of the paranasal sinuses

The CT appearances of 13 cases of pathologically proven aspergillosis involving paranasal sinuses were reviewed. Symptoms included rhinorrhea, nasal obstruction, headache, facial pain and foul smell from the nose. At operation, these lesions appeared yellowish, brownish, grey or black in colour, and contained dirty or muddy material. Microscopic examination of the tissue removed showed an Aspergillus ball with chronic inflammation but without invasion of the nasal or sinus mucosa in 6 cases, and tissue invasion with necrosis and inflammation in 7. The structures involved, in order of frequency, were: maxillary sinus, nasal cavity, ethmoid sinus, orbit and cavernous sinus. The orbit was involved in 2 cases, therefore categorized as invasive; the other 11 cases were non-invasive as judged by CT. Calcification was seen in the lesions of 9 cases. In most cases the adjacent bony structures showed areas of erosion and sclerosis. Aspergillosis should be suspected in the presence of a mass in the paranasal sinuses or nasal cavity with calcification within it, which may not appear solid or dense and is separate from the walls of the sinus.

Reduced absolute rate of myo-inositol biosynthesis of cultured bovine retinal capillary pericytes in high glucose

De novo biosynthesis of myo-inositol (MI) by permeabilized cultured bovine retinal capillary pericytes (BRCP) and feline retinal pigment epithelial cells (FRPE), grown in different concentrations of glucose, were studied. After incubation with a physiological concentration of [14C]glucose 6-phosphate (G6P), the radioactive G6P derivatives were quantitated by a single HPLC column. Based on the determined specific activity of [14C]G6P, activities of inositol 1-phosphate synthase (MI synthase) were calculated. The activity of MI synthase was reduced 48% by growing BRCP in a high-glucose medium (20 mM) in comparison with that in the normal medium (glucose 5 mM). In contrast, the de novo MI biosynthesis by FRPE was not changed with increasing concentrations of glucose in the medium. As compared with MI uptake previously studied, the synthesized MI contributes a substantial proportion of cellular MI pool in BRCP. Therefore, in BRCP growing in high glucose the reduced MI biosynthesis aggravates the low MI content resulting from the inhibited MI uptake, and thus leads to altered inositol phospholipid metabolism.

Squamous cell carcinoma of the lip

We reviewed 39 cases of squamous cell carcinoma of lip from 53 consecutive patients with carcinoma of the lip. The retrospective review includes age, location, risk factors, TNM classification, histologic differentiation, treatment methods, recurrent disease, site of recurrence, and follow-up status. Results reveal prognosis is related to original tumor size, local recurrence, and presence of cervical metastasis. Aggressive surgical treatment is recommended for identifiable poor prognostic lesions and includes surgical excision, prophylactic suprahyoid neck dissection, and possible radical neck dissection.

Oral leiomyoma: case report

Leiomyoma of the oral cavity is infrequently found because of the scarcity of smooth muscle in the mouth. A review of the literature yielded only 124 cases reported from 1884 to 1987. A new case of primary leiomyoma of the lower buccal sulcus is presented. Although the recurrence rate has been very low, wide surgical excision is recommended because of the high incidence of malignancy of this tumor in the oral cavity contrasted with other parts of the body.

Polar-liquid, derivatized cyclodextrin stationary phases for the capillary gas chromatography separation of enantiomers

A new class of hydrophilic, relatively polar liquid, cyclodextrin (CD) derivatives have been used as highly selective chiral stationary phases (CSPs) for capillary gas chromatography (GC). Several possible requirements for liquidity in CD derivatives are discussed. O-(S)-2-Hydroxypropyl derivatives of alpha-, beta-, and gamma-cyclodextrins were synthesized, exclusively characterized, permethylated, and evaluated for enantioselectivity. Seventy pairs of enantiomers were resolved. They represent a wide variety of structural types and classes of compounds including chiral alkyl amines, amino alcohols, epoxides, pyrans, furans, sugars, diols, esters, ketones, bicyclic compounds, alcohols, and so on. Many of these compounds were not aromatic and cannot be resolved on any known liquid chromatographic CSP. Often, these enantiomers had far less functionality than required for LC separation. General properties of these CSPs as well as possible insights into the separation mechanism are discussed.

Metastatic malignant melanoma of upper gastrointestinal tract

A 74-year-old male patient developed intermittent melena and anemia after he had received surgical resection for malignant melanoma of the right foot and radical dissection of the right inguinal metastatic lymph node. The source of bleeding was identified to be metastatic melanoma of stomach and duodenum by panendoscopy and biopsy. Patient refused surgical intervention and died of pneumonia two weeks later.

Determination of the antimitotic agents N-desacetylcolchicine, demecolcine and colchicine in serum and urine

In an effort to characterize the pharmacokinetic behavior of the antimitotic agent N-desacetylcolchicine a selective, sensitive high-performance liquid chromatographic method was developed for the determination of N-desacetylcolchicine, demecolcine and colchicine in serum or urine. To 0.5 ml of serum or 0.1 ml of urine diluted to 0.5 ml were added 50 microliters demecolcine (2 micrograms/ml) which serves as the internal standard. The sample was extracted using a C2 reversed-phase solid extraction column. N-Desacetyl-colchicine, colchicine and the internal standard were eluted from the column with methanol. The combined eluates were evaporated to dryness and the residue was reconstituted with water. The reconstituted sample was injected into a C18 reversed-phase column and eluted using a mobile phase consisting of 0.1 M potassium dihydrogenphosphate, 5 mM 1-pentanesulfonic acid in methanol and acetonitrile with a final pH of 6.0, at a flow rate of 1.5 ml/min. N-Desacetylcolchicine, colchicine and the internal standard were detected using a variable-wavelength ultraviolet detector at 254 nm. The limit of detection was 0.4 ng/ml for desacetylcolchicine and 4.0 ng/ml for colchicine. The method is linear over a concentration range of 1.0-200 ng/ml. The method has been shown to be a rapid, reliable method to monitor N-desacetylcolchicine levels in clinical trials in cancer patients.

Intramural pericyte degeneration in early diabetic retinopathy study in vitro

An experimental model of diseased pericytes was established by using cultured bovine retinal capillary pericytes in high--glucose medium. The high glucose stimulated polyol pathway, reduced cellular myo-inositol content and disturbed inositol phospholipid metabolism which resulted in a decrease in inositol trisphosphate (IP3) level. The correlation of suppressed IP3 levels with reduced DNA synthesis was evident. These findings suggested the biochemical mechanism by which retinal pericytes degenerate in high glucose. To supplement myo--inositol and/or an aldose reductase inhibitor to the high--glucose medium largely reversed the suppressed IP3 level and the decreased DNA synthesis. Therefore, these two manipulations may be considered as in vitro therapy to treat sick pericytes induced by high glucose.

CT evaluation of polymorphic reticulosis

For the understanding of the CT findings of polymorphic reticulosis involving the upper respiratory tract, we reviewed eleven cases of this disease with initial CT study before treatment. CT revealed masses or swelling in the nose or nasal chamber, often with involvement of paranasal sinuses and medial parts of the orbit. In some, nonspecific minimal bony change (either bone destruction or bone sclerosis) was found. These CT findings are not specific. Any large mass in the nose and nasal fossa with little associated bone destruction should, however, raise the differential diagnosis of polymorphic reticulosis.

[Abnormal inositol phospholipid metabolism as a main factor causing pericyte drop-out in diabetic retinopathy]

The biochemical basis of pericyte loss in early diabetic retinopathy is still an open question. In studies on the mechanism by which retinal pericytes degenerate, we first established a bovine retinal capillary pericyte (BRCP) cell line. Subcultured BRCP grown in high (10-40 mmol/L) glucose media were used as an experimental model. We found that high concentrations of glucose suppress the mitotic rate and cell birth rate of cultured BRCP. High concentrations of glucose inhibit myo-inositol transport and result in decreased intracellular myo-inositol content. This inhibition can be partially reversed by sorbinil, an aldose reductase inhibitor (ARI). Myo-inositol is a precursor of inositol phospholipids (IPLs), whose metabolism is responsible for a number of signal transduction processes. Phosphoinositidase (PIase) cleaves the phosphodiester bond of phosphotidylinositol 4,5 diphosphate (PIP2) to produce two second messengers, inositol trisphosphate (IP3) and diacylglycerol (DG). Further experiments showed that IP3 and DG synergistically activate BRCP proliferation in vitro. High concentrations of glucose altered the formation of both IPLs and inositol phosphate esters (IPEs) in an organ culture of retinal microvessels. This alteration can be reversed by adding either high concentrations of myo-inositol or ARI to the medium. PIase activity was attenuated to 82% or 55% when glucose in the growth medium was increased from 5 to 15 or 30 mmol/L, respectively. When IPLs from BRCP were analyzed by HPLC and TLC, we observed the reduction of three IPLs, including the substrate of PIase, PIP2.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of expression of exogenous PDGF-A chain on growth and transformation of CHO cells]

CHO cells were transfected with plasmid pSV2-PDGF-A (containing human PDGF-A cDNA) by calcium phosphate method. Twenty transfected cell lines were obtained after G418 selection. The selected 2 cell lines At1 and Aot7), with prominent changes in morphology and growth behaviour, showed transcription of PDGF-A chain mRNA much higher than CHO cells, strong fluorescent PDGF-specific reaction, appearing that PDGF-like proteins were synthesized in cytoplasm of these cells. At1 and Aot7 cells not only had increased growth rate, but also formed large colonies in soft agar and grew into fibrosarcomas in nude mice. These results suggested that the expression of exogenous PDGF-A gene might cause the uncontrolled growth and malignant transformation of CHO cells.

DNA-synthesis regulation and correlation with inositol trisphosphate levels in cultured bovine retinal capillary pericytes

Inositol phosphate (IP), inositol bisphosphate (IP2) and inositol trisphosphate (IP3) in cultured bovine retinal capillary pericytes (BRCP) were quantitated by an ion-pair reverse-phase HPLC. BRCP were grown in media with standard (5 mM) or high (30 mM) glucose, and were either labeled with myo-[2-3H]inositol (20 microCi ml-1) for 60 hr or with dual isotopes (20 microCi ml-1 myo-[2-3H]inositol and 2 microCi ml-1 [14C]glycerol) for 8 hr. In parallel, BRCP in different glucose-media were incubated with 1 microCi ml-1 [3H]thymidine for 4 hr. High glucose significantly suppressed the accumulation of [3H]label in IP, IP2 and IP3, and specifically reduced the incorporation of [14C]glycerol into inositol phospholipids, but not that of neutral lipids and other types of phospholipids. The reduced IP3 level correlated with the decrease in the incorporation of [3H]thymidine into DNA. Both the reduced IP3 formation and DNA synthesis which were induced by high glucose were significantly reversed by adding either myo-inositol or AL1576, an aldose reductase inhibitor (ARI). However, the addition of neither myo-inositol nor ARI stimulated IP3 formation and/or DNA synthesis when BRCP were grown in the standard medium (5 mM glucose). These findings indicate that myo-inositol metabolism and the polyol pathway affect inositol phospholipid-mediated pericyte division in vitro only under the high-glucose condition. These data are compatible with the hypothesis that altered inositol phospholipid metabolism accounts for the loss of pericytes in diabetic retinopathy.

[Expression of exogenous platelet-derived growth factor B chain gene in CHO cells]

CHO cells were transfected with plasmid pSM-1 (containing human c-sis cDNA) singly or co-transfected with pSV 2 neo DNA by calcium phosphate method. After low serum or G418 selection several cell lines with expression of platelet-derived growth factor (PDGF) were obtained. One among them, FB5, was of the highest PDGF expression and showed the following biological characteristics when compared with CHO cells: (1) a prominent change in morphology from spindle to round in shape: (2) increase of growth rate; (3) growth in low serum (2%) medium as a semisuspension culture; (4) growth on soft agar to larger colonies; (5) synthesis of PDGF in cytoplasm identified by immunofluorescent method; (6) the conditioned medium stimulated DNA synthesis of NRK cells; (7) RNA dot hybridization showing high transcription of PDGF mRNA; (8) southern blot showing integration of human c-sis gene was still stable after 7 months. These results indicated that intergration of exogenous c-sis gene and its high expression might cause CHO cells to high growth rate and even transformation. The establishment of this stable transformed cell line, FB5 is thought to be a good model for further study on the function of PDGF in cell growth control and cell transformation.

[The biochemical mechanism in vitro of pericyte drop-out in diabetic retinopathy]

An experimental pathologic model of pericyte drop-out was established with capillary pericytes in culture medium of high glucose concentration. The high glucose activated the sorbitol pathway, reduced the intracellular myo-inositol content and disturbed the inositol phospholipid metabolism which resulted in a decrease in the inositol trisphosphate (IP3) level. The correlation of suppressed IP3 level with reduced DNA synthesis was evident, suggesting the mechanism that retinal pericytes degenerated in high glucose concentration. In vitro test of adding myo-inositol and/or aldose reductase inhibitor to the high-glucose medium reversed the inositol phospholipid metabolism and the decreased DNA synthesis, which could hold promise for the clinical prevention and treatment of early diabetic retinopathy.

[DNaseI sensitivity and DNaseI hypersensitive sites of AFP gene correlated with the gene expression]

Using rat AFP cDNA clone pRAF87 and subcloned 5' end fragment of AFP gene as probes, we have analysed the DNaseI sensitivity and DNaseI hypersensitive sites of AFP gene in chromatin of rat fetal liver (active transcription), adult liver (potentially active transcription) and adult kidney (inactive transcription). The results indicated that fetal liver AFP genes are much more sensitive than their counter parts. There are three DNaseI hypersensitive sites in the fetal AFP gene, namely, upstream -3kb region, 1.37kb region just around transcription start sites and the last located in downstream 4.1 kb EcoR I fragment. The 1.37 kb DNasI hypersensitive site also exists in adult liver. The relationship between AFP gene DNaseI sensitivity, DNaseI hypersensitive sites and AFP gene expression have been discussed.

Acute cerebrovascular disorder induced by allergic vasculitis. A case report

A patient with vascular disease of the brain due to allergic vasculitis, which had been misdiagnosed for many years, was given anti-inflammatory, antituberculosis and antitumor drugs with no avail. He was admitted this time for an attack after eating food prepared with leftover oil used for frying hairtail. Considering the possibility of allergic vasculitis, we tried antianaphylactics and immunosuppression drugs including dexamethasone with satisfactory results. The final diagnosis was allergic granulomatous vasculitis.

Attenuation of phosphoinositidase activity and phosphatidylinositol bisphosphate level of bovine retinal capillary pericytes in high glucose

Both phosphoinositidase (PIase) and individual species of inositol phospholipid (IPL) of bovine retinal capillary pericytes (BRCP) were quantitatively determined. When glucose in growth medium was increased from 5- to 15- or 30 mM, PIase activity was attenuated to 82% or 55%, respectively. In contrast, when glucose (5-, 15-, 30 mM) was added to an enzyme extract from cells grown in the standard growth medium (5 mM glucose, 0.04 mM myo-inositol) the PIase activity was not changed, indicating that the reduced PIase activity was not due to the direct effect of glucose. When IPLs from BRCP were analysed by HPLC and TLC, we observed reduction of the total and newly formed IPLs including the substrate of PIase. Phosphatidylinositol bisphosphate (PIP2). Reduced levels of IPLs were associated with a decrease in myo-inositol and an increase in sorbitol. The changes in IPL metabolism were reversed by adding either free myo-inositol or AL1576, an aldose reductase inhibitor (ARI), to the high-glucose medium. However, the addition of myo-inositol to the growth medium with a standard concentration of glucose only caused a marked increase in phosphatidylinositol, but not in PIP or PIP2, while the supplement of AL1576 in the standard medium did not cause any changes in IPL formation. These findings suggest that the alteration in IPL metabolism in BRCP may be related to insufficient myo-inositol or activated sorbitol pathway under high-glucose conditions. Further explanation of the role of the altered hydrolysis of PIP2 triggered by PIase may provide clues to understanding of the mechanism of decreased pericyte viability in the presence of high glucose concentrations.

Activation of Mg-ATPase of skeletal-muscle myosin by bovine retinal pigment epithelial actin

The morphology and function of actin in cultured bovine retinal pigment epithelial (RPE) cells were studied. Filamentous actin was identified with a fluorescent mushroom toxin, nitrobenzoxadiazole (NBD)-phallacidin, specific for actin. Dark-field microscopy of cultured RPE cells revealed numerous pigment granules; fluorescent microscopy identified scattered lipofuscin granules. One-dimensional SDS polyacrylamide gel electrophoresis of urea-soluble proteins extracted from RPE cells showed a 46,000-dalton protein band which comigrated with authentic muscle actin. Densitometric scanning showed that this protein band comprised 7.6% of the total urea-soluble proteins. An actin-activated skeletal-muscle myosin Mg-ATPase assay, using skeletal-muscle heavy meromyosin as enzyme and [gamma-32P]-ATP as substrate, demonstrated functional actin in RPE cell extracts after DEAE-cellulose anion exchange chromatography. The actin-containing protein fractions were eluted at ionic strengths between 0.19 and 0.36 M KCl. The activation of myosin ATPase by actin in RPE cells provides a molecular basis for the phagocytic activity which is important in maintaining the integrity of retinal photoreceptor cells.

Prostacyclin is the major prostaglandin synthesized by bovine retinal capillary pericytes in culture

Prostaglandin synthesis by bovine retinal pericytes was investigated using high pressure liquid chromatography to separate and identify 3H-labeled prostaglandins released from 3H-arachidonic acid labeled pericyte monolayers. A dominant peak activity corresponding to 6-keto-PGF1 alpha was observed. This peak was eliminated when monolayers were pretreated with cyclooxygenase inhibitors and was augmented when monolayers were stimulated by the calcium ionophore A23187. Suspensions of pericytes and the cell-free media of monolayers incubated with arachidonic acid inhibited adenosine diphosphate-, collagen-, and arachidonic acid-stimulated platelet aggregation in a bioassay for prostacyclin-like activity. This inhibitory activity was unstable at room temperature. Cultures of 7.5 to 10 x 10(5) pericytes (7th passage near-confluence) released nanogram quantities of 6-keto-PGF1 alpha as measured by radioimmunoassay. These results are evidence that prostacyclin is the main prostaglandin synthesized by bovine retinal capillary pericytes in culture. Pericytes may influence the microcirculation via their production and release of this potent vasoactive arachidonic acid metabolite.

Reduction of inositol triphosphate in retinal microvessels by glucose and restimulation by myo-inositol

The formation of inositol phospholipids (IPLs) and inositol phosphate esters (IPEs) in response to glucose was studied in isolated retinal microvessels from porcine eyes. Retinal microvessels incubated from 60 hr with myo-[3H]inositol were sequentially extracted to obtain IPLs and IPEs. [3H]Inositol-labelled IPLs were deacylated to produce the corresponding glycero derivatives. Both deacylation products and water-soluble IPEs were monitored by anion-exchange chromatography. In the presence of high glucose (30 mM) the labelling in inositol triphosphate (IP3) was reduced to 77% and was restimulated by adding myo-inositol (final concentration 0.4 mM) to 158% of the control under physiological conditions of glucose (5 mM) and myo-inositol (0.04 mM). With a fixed glucose concentration (5 mM), IPE accumulation was observed with increasing concentrations of exogenous myo-inositol. Under physiological conditions (glucose 5 mM, myo-inositol 0.04 mM) the distribution (percentage) of radioactivity in phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP) and phosphatidylinositol 4,5-phosphate (PIP2) was 63:19:18. The myo-inositol concentration dependence of IPL formation was also demonstrated. A decrease in IP3 in response to high glucose without changing PIP2 but with a reduction in PI indicated that PI may act as a reservoir to replace a possible loss of PIP2. These findings suggest that availability of myo-inositol by retinal microvessels may be essential to maintain the normal signal transduction and cell proliferation associated with IPL turnover under high glucose concentration.

Kinetics of ascorbate transport by cultured retinal capillary pericytes. Inhibition by glucose

Accumulation of radioactive L-[carboxyl-14C]-ascorbic acid by cultured bovine retinal capillary pericytes was studied. Kinetic analysis of the transport showed a time-dependent, saturable system with an apparent Km of 76.0 microM and a Vmax of 42 pmole/micrograms DNA/min. A facilitated carrier diffusion process was established on the basis that the system was not sensitive to 2,4-dinitrophenol, ouabain, or reduced sodium concentration in the incubation media, and that the carrier system demonstrated stereospecificity for an ascorbate analogue, dehydroascorbate, and for sugar analogues such as alpha-D-glucose and 3-0-methyl-D-glucose (3-0-MG), but not for beta-D-fructose or L-glucose. Transport of ascorbate by cultured pericytes was insulin-insensitive. 3-0-Methyl-D-glucose inhibited ascorbate transport into pericytes in a non-competitive manner with a Ki of 22 mM. These results indicate that, in cultured retinal capillary pericytes, a common facilitated carrier diffusion system is involved in the transport of ascorbate and sugar analogues such as alpha-D-glucose or 3-0-MG.

Actin in cultured bovine retinal capillary pericytes: morphological and functional correlation

Actin in cultured bovine retinal capillary pericytes was identified and partially characterized biochemically. The filamentous actin was localized in bovine retinal capillary pericytes using a fluorescent mushroom toxin (nitrobenzoxadiazole-phallacidin) specific for actin. One-dimensional SDS-polyacrylamide-gel electrophoresis of urea-extracted proteins from bovine retinal capillary pericytes revealed a 46,000 MW protein band corresponding to an actin standard, which comprised 7.3% of the total urea-soluble proteins. Actin-activated skeletal muscle myosin Mg2+-ATPase assay, using [gamma-32P]-ATP as substrate, demonstrated functional actin in bovine retinal capillary pericyte extracts after DEAE-cellulose anion-exchange chromatography. The actin-containing protein fractions were eluted at ionic strengths between 0.25 and 0.35 M KCl. The presence of functional actin in pericytes indicated the ability to generate contractile force. This contraction-generating ability may allow pericytes to regulate microvessel caliber and to maintain the integrity of the capillary wall. A lack of this function when pericytes are preferentially lost in diabetic retinal microangiopathy could destabilize the microvessel wall and predispose the capillary to further pathologic changes.

Induction of class II (Ia) alloantigen expression on corneal endothelium in vivo and in vitro

Class II (DR or Ia) alloantigens are potent inducers of cell-mediated immune responses. However, the expression of Class II alloantigens on corneal cells, except for Langerhans cells within the limbal epithelium, has not previously been described. We have induced Ia expression on cultured rabbit corneal endothelial cells with human immune interferon, and have demonstrated numerous Ia-positive cells in the endothelium during primary immunogenic uveitis in vivo. Cultured endothelial cells which had been treated with immune interferon in vitro functioned as stimulator cells in a mixed leukocyte reaction. Induction of Class II alloantigen expression by lymphokines may potentiate corneal allograft rejection.

Translation of type IV procollagen messenger RNA from cultured cat retinal pigment epithelial cells

The activity of type IV procollagen mRNA was detected in the total cytoplasmic RNA prepared from normal feline retinal pigment epithelial cells in culture. The translation products contained two distinct bands in the pro alpha chain region on SDS-PAGE, which were sensitive to collagenase digestion. Corresponding bands were identified in the immunoprecipitate of the translation products after reaction with an anti-type IV collagen antiserum and separation by protein A-Sepharose column chromatography.

Examination of the interrelationship between aliphatic group dipole moment and polar substituent constants

The relationships between 210 aliphatic group dipole moments (mu) and Taft polar constants (sigma *) are explored, and they are shown to be correlated by a general equation: mu = -a X sigma * -b X n' -c, where a, b, and c are constants. The value n' is a parameter reflecting the attenuating factor due to the number and electronic nature of the interval atoms between the most electronegative atom and the first atom connected to the acetate in the measurement of sigma *. The mu and sigma * values of over 214 aliphatic substituents are compiled for future correlation studies. Comparative examples using sigma * and mu in quantitative structure-activity relationships are presented.

Increased solubility of newly synthesized collagen in retinal capillary pericyte cultures by nonenzymatic glycosylation

The effect of increasing glucose concentration on the solubility of newly synthesized collagen was studied in bovine retinal capillary pericyte (BRCP) cultures. Synchronized pericytes were labeled with [3H]-proline in media containing either 5, 10, 20 or 40 mM glucose, or 5 mM glucose and 100 micrograms/ml beta-aminopropionitrile fumarate (BAPN). The relative rate of collagen synthesis in the medium (soluble collagen) was significantly increased, and the rate in the cell layer (insoluble collagen) was decreased, by an elevated glucose concentration. The increase in collagen solubility with 20 and 40 mM glucose (over normal, 5 mM glucose) was 14 and 42%, respectively, of that obtained with BAPN. BAPN and 4-deoxypyridoxine inhibited BRCP lysyl oxidase activity, but elevated glucose concentrations did not. Increased nonenzymatic glycosylation of newly synthesized collagen was demonstrated in BRCP cultures co-labeled with L-[14C]-glucose and L-[3H]-proline. The increase in collagen solubility with elevated glucose concentrations therefore appears to be the result of the inhibition of lysyl-derived cross-link formation because of an increased nonenzymatic glycosylation of the epsilon-amino groups of lysyl residues of newly synthesized collagen in culture.