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At least 235 records · Page 13Linked to original sources
PubMed1990

Treatment of hepatocellular carcinoma by segmental hepatic artery injection of adriamycin-in-oil emulsion with overflow to segmental portal veins.

Hepatocellular carcinoma was treated with slow injection of an emulsion containing 40 to 60 mg of adriamycin and 3.5 to 12 ml of Lipiodol into the portal vein via a segmental hepatic artery. During and after the injection, the portal branches of the segment were demonstrated. Six patients with resectable hepatocellular carcinoma received this treatment, which in 3 of them was followed by embolization with Gelfoam of the segmental artery. In these 3, all main tumors and daughter nodules became completely necrotic, but some infarction developed in the non-tumorous area. Those without Gelfoam had complete necrosis of all daughter nodules, but incomplete response of the main tumor. This combined treatment may be recommended for patients with localized lesions which are nonresectable due to cirrhosis, or for other reasons.

Aged↗
PubMed1997

[Efficiency of segmental SMANCS/Lip-TAE for hepatocellular carcinoma--comparative studies in the efficacy of segmental SMANCS/Lip-TAI].

We compared the segmental SMANCS/Lip-TAI and the segmental SMANCS/Lip-TAE and studied the effectiveness of both treatments and the influence and/or the side effects on liver function. In resected cases, we studied histopathologic examination. The response rate of the group treated by TAI was 28.6%, and that of the group treated by TAE was 76.5%. In the group treated by TAE, the therapeutic effects were good in nodular type HCC, using small doses of SMANCS. In both groups, the incidence and degree of side effects showed no significant difference. Hepatic insufficiency occurred in a few cases of the group treated by TAI. In resected cases, viable areas remained below the tumor capsule. In conclusion, segmental SMANCS/Lip-TAE seemed to be an effective treatment without any serious complications.

Aged↗
PubMed1998

[Comparative studies on the antitumor activities and side effects of segmental SMANCS/Lip-TAE with segmental SMANCS/Lip-TAI for hepatocellular carcinoma].

We compared the effectiveness of treatments and the influence of side effects on liver function and clinical symptoms between segmental SMANCS/ Lip TAI and segmental SMANCS/Lip-TAE. The early tumor response rate of the group treated by TAI was 23.6%, and that of the group treated by TAE was 80.0%. In the group treated by TAE, the therapeutic effects were better in the nodular type than in the diffuse type of HCC, and we were also able to obtain a good tumor response rate on the multiple HCC and large HCC. However, there was no difference in the response period between the groups treated by TAI and TAE. In both groups, there were no significant differences in the appearance rate and degree of side effects. In conclusion, segmental SMANCS/Lip-TAE seemed to be an effective treatment for HCC without any serious complications.

Aged↗
PubMed1989

Treatment of breast cancer with segmental mastectomy alone or segmental mastectomy plus radiation.

A retrospective review of the outcome of treatment for primary, Stage I and II breast cancer with segmental mastectomy (SGM) alone or segmental mastectomy plus postoperative irradiation (SGM + RT) at four Rochester, New York, city hospitals is reported. Between January 1971 and March 1984, 99 women were treated with SGM and 146 with SGM + RT. Groups were similar regarding significant clinical and histologic prognostic factors; they differed, however, in that the SGM group was considerably older (means = 72) than the SGM + RT group (means = 56). Among SGM patients, local and total locoregional failure was 26.44 and 35.2%, respectively. Local and total locoregional failure (7.6 and 12.4%, respectively) was significantly reduced among patients treated with SGM + RT (p less than 0.0001). Among SGM patients, there was scant advantage in enlarging the extent of resection from local excision (29.5% local failure) to wide local excision (27.3%) to quadrantectomy (22.2%). Among women receiving SGM + RT, similar rates of local failure occurred among patients receiving local excision (15.5%) and wide local excision (12.5%). By contrast, only 2.8% of those receiving quadrantectomy failed. Results are viewed as supportive of findings of NSABP-B06. Findings suggest that SGM constitutes inadequate treatment of Stage I and II breast cancer. Locoregional failure rates of 30-40% may be reduced to around 10% with postoperative irradiation.

Adult↗
PubMed2004

Anterior segment inflammation and hypotony after posterior segment surgery.

Recent advances in the instrumentation and surgical techniques for posterior segment surgery permit better anatomic and functional outcomes. Nevertheless, these procedures may be associated with complications involving the anterior segment, including postoperative inflammation and hypotony. One must differentiate infectious from noninfectious inflammation to initiate appropriate therapy promptly. Hypotony is a frustrating problem because it is difficult to reverse. The exclusion of eyes with other known causes of hypotony is important before establishing the putative mechanism of tractional ciliary body detachment caused by epiciliary proliferative tissue.

Anterior Eye Segment↗
PubMed2005

Light-induced oxidation of photoreceptor outer segment phospholipids generates ligands for CD36-mediated phagocytosis by retinal pigment epithelium: a potential mechanism for modulating outer segment phagocytosis under oxidant stress conditions.

Clearance by the retinal pigment epithelium (RPE) of shed photoreceptor outer segments (OSs), a tissue with one of the highest turnover rates in the body, is critical to the maintenance and normal function of the retina. We hypothesized that there is a potential role for photo-oxidation in OS uptake by RPE via scavenger receptor-mediated recognition of structurally defined lipid peroxidation products. We now demonstrate that specific structurally defined oxidized species derived from arachidonyl, linoleoyl, and docosahexanoyl phosphatidylcholine may serve as endogenous ligands on OSs for uptake by RPE via the scavenger receptor CD36. Mass spectrometry studies of retinal lipids recovered from dark-adapted rats following physiological light exposure demonstrate in vivo formation of specific oxidized phosphatidylcholine molecular species possessing a CD36 recognition motif, an oxidatively truncated sn-2 acyl group with a terminal gamma-hydroxy(or oxo)-alpha,beta-unsaturated carbonyl. Cellular studies using RPE isolated from wild-type versus CD36 null mice suggest that CD36 plays a role in engulfment, but not initial binding, of OSs via these oxidized phospholipids. Parallel increases in OS protein-bound nitrotyrosine, a post-translational modification by nitric oxide (NO)-derived oxidants, were also observed, suggesting a possible role for light-induced generation of NO-derived oxidants in the initiation of OS lipid peroxidation. Collectively, these studies suggest that intense light exposure promotes "oxidative tagging" of photoreceptor outer segments with structurally defined choline glycerophospholipids that may serve as a physiological signal for CD36-mediated phagocytosis under oxidant stress conditions.

Animals↗
PubMed1985

Frog rod outer segments with attached inner segment ellipsoids as an in vitro model for photoreceptors on the retina.

Purified suspensions of frog rod outer segments still attached to the mitochondria-rich inner segment portion of the receptor cell (OS-IS) can be obtained in quantities (0.1 mg/retina) sufficient for chemical analysis. In oxygenated glucose-bicarbonate Ringer's medium with added Percoll, they display normal dark currents, light sensitivity, and photocurrent kinetics for several hours. Two millimolar cytoplasmic levels of ATP and GTP are maintained, fivefold higher than in isolated OS. The levels are not altered by abolition of the dark current with ouabain. Nucleoside triphosphates are more effectively buffered than in isolated OS, and their levels remain constant during changes in external calcium levels. 32Pi is incorporated into endogenous ATP and GTP pools twice as efficiently as in isolated OS, and is used in the phosphorylation of rhodopsin. OS-IS take up and release 45Ca++ by Na+-, Ca++-, and IBMX-sensitive mechanisms. Illumination causes release of 45Ca++, which confirms retinal studies by other groups using Ca++-sensitive electrodes. Thus, OS-IS suspensions model the behavior of photoreceptors still attached to the living retina. Their availability permits the simultaneous assay and correlation of electrophysiological and chemical changes occurring during excitation and adaptation.

Adenosine Triphosphate↗
PubMedDate not supplied

A clinicopathologic study of focal segmental glomerulosclerosis: comparison between nephrotic and non-nephrotic focal segmental glomerulosclerosis.

Seven out of 16 patients with primary focal segmental glomerulosclerosis (FGS) did not showed the nephrotic syndrome throughout their clinical courses, and then patients with FGS could be divided into the two groups, nephrotic FGS group (NS-G) and non-nephrotic one (NO-G). The clinicopathologic findings of NS-G and NO-G were compared retrospectively to define the pathogenesis of the glomerular disease in FGS. No significant differences were found between the groups except for proteinuria and serum total protein or albumin, and it was impossible to distinguish the two groups only histologically. In addition, electron microscopic study revealed that the glomerular epithelial cell was altered more than the endothelial and mesangial cells in both groups, resulting in vacuolization, foot process fusion, and detachment, and the striking fact that the glomerular epithelial vacuoles consisted mainly of the dilated rough endoplasmic reticulums (RERs). The speculation is drawn that in FGS the glomerular epithelial cell is firstly damaged by unknown factor(s), manifested functionally proteinuria and/or hematuria, morphologically dilatation of RER, foot process fusion, detachment, and eventually segmental sclerosis and hyalinosis.

Adolescent↗
PubMed1990

The clinical significance of the glomerular location of segmental lesions in focal segmental glomerulosclerosis.

Serial sections of renal biopsies obtained from 44 nephrotic children with focal segmental glomerulosclerosis (FSGS) were reviewed in order to determine the glomerular location of segmental lesions and relate the findings to the outcome of illness. There were 23 boys and 21 girls aged 0.9-14.2 years at onset. FSGS was classified as "hilar" in biopsies containing at least one lesion contiguous with or involving the hilum, regardless of the location of other lesions, and as "peripheral" in the absence of hilar lesions. Of the 44 initial biopsies, 33 were designated hilar and 6 peripheral; the remaining 5 were unclassifiable as it was not possible to determine the location of 1-3 lesions in each biopsy. Twenty-eight of the 33 hilar biopsies also contained peripheral lesions, including paratubular (glomerular "tip") lesions in 15 instances. Paratubular lesions as the predominant abnormality were observed in only four biopsies. Repeat biopsies showed that transition occurred from one type to another, and only 4 biopsies remained with a final designation of peripheral FSGS. After a follow-up period of 1.6-24.9 years (mean 9.3), there was no significant difference in outcome between hilar and peripheral FSGS, whether diagnosed on the initial or repeat biopsy. The division into separate categories is not clearcut, and the use of this as a prognostic aid does not justify the additional cost of preparing and examining numerous serial sections.

Adolescent↗
PubMed2000

A 38 kb segment containing the cdc2 gene from the left arm of fission yeast chromosome II: sequence analysis and characterization of the genomic DNA and cDNAs encoded on the segment.

A genomic 38 kbp segment on the c1750 cosmid clone containing the cdc2 gene, located in the left arm of chromosome II from Schizosaccharomyces pombe, was sequenced. The segment was found to have five previously known genes, pht1, cdc2, his3, act1 and mei4. Among 11 coding sequences (CDSs) predicted by the gene finding software INTRON.PLOT., four CDSs, pi007, pi010, pi014 and pi016, had considerable similarity to 40S ribosomal protein, glycosyltransferase, cdc2-related protein kinase and alpha-1, 2-mannosyltransferase, respectively. Another unusually huge open reading frame (ORF) (pi011), consisting of 2233 amino acids, existed, having significant homology to alpha-amylase, granule-bound glycogen synthase and the Sz. pombe YS 1110 clone product at the N-terminal, middle and C-terminal regions, respectively. All the predicted 11 CDSs were experimentally analysed by RACE PCR. The sequencing of the RACE products revealed that there were two small overlaps at the 3' untranslated regions (UTRs) between pi004 and pi005 (17 bp) and between pi007 and pi008 (2 bp). The distances between 5' end of the 5'UTR and the putative translation initiation codon varied from 10 to 302 nucleotides (nt) among the nine CDSs successfully analysed by 5'-RACE. The expression level of each CDS on this clone was determined. Among the 16 genes on this clone, the previously determined genes, pht1, cdc2, his3 and act1, were found to be most highly expressed. Finally, cDNAs of all the newly identified genes were detected by RACE, proving the actual expression of these genes. The nucleotide sequence has been submitted to the EMBL database under Accession No. AB004534.

Base Sequence↗
PubMed1997

Physicochemical properties and platelet interactions of segmented polyurethanes containing sulfonate groups in the hard segment.

The adhesion of platelets to a series of segmented polyurethanes having sulfonate groups in the hard segment is reported. The polyurethanes were synthesized using sulfonated chain extenders of different structure. Analogous control materials without sulfonate groups also were studied. Adhesion was measured in vitro using washed human platelets in a carrier fluid consisting of Tyrode's buffer with apyrase, albumin, and red cells at normal concentration. The polymers were characterized by gel permeation chromatography and elemental analysis. Water absorption and thermal transitions also were determined. It was found that the sulfonated materials absorb significant amounts of water while the nonsulfonated analogs do not. The surfaces of polymer films were characterized by water contact angle and XPS. The contact angles of the sulfonated surfaces were relatively low. Platelet adhesion to the sulfonated polymers was found to be very high compared to the nonsulfonate analogs. The local environment of the sulfonate groups (different chain extenders) also appears to have an effect on platelet interactions. Albumin adsorption was high on all the materials and was not correlated with platelet adhesion. It appears from this work that platelets may have a binding site that is specific for sulfonate groups.

Adsorption↗
PubMed2007

Tuning the beta-turn segment in designed peptide beta-hairpins: construction of a stable type I' beta-turn nucleus and hairpin-helix transition promoting segments.

Designed octapeptides Boc-Leu-Val-Val-Aib-(D)Xxx-Leu-Val-Val-OMe ((D)Xxx = (D)Ala, 3a;(D)Val, 3c and (D)Pro, 5a) and Boc-Leu-Phe-Val-Aib-(D)Ala-Leu-Phe-Val-OMe (3b) have been investigated to construct models of a stable type I' beta-turn nucleated hairpin and to generate systems for investigating helix-hairpin conformational transitions. Peptide 5a, which contains a central Aib-(D)Pro segment, is shown to adopt a stable type I' beta-turn nucleated hairpin structure, stabilized by four cross-strand hydrogen bonds. The stability of the structure in diverse solvents is established by the observation of all diagnostic NOEs expected in a beta-hairpin conformation. Replacement of (D)Pro5 by (D)Ala/(D)Val (3a-c) results in sequences that form beta-hairpins in hydrogen bonding solvents like CD(3)OH and DMSO-d(6). However, in CDCl(3) evidence for population of helical conformations is obtained. Peptide 6b (Boc-Leu-Phe-Val-Aib-Aib-Leu-Phe-Val-OMe), which contains a centrally positioned Aib-Aib segment, provides a clear example of a system, which exhibits a helical conformation in CDCl(3) and a significant population of both helices and hairpins in CD(3)OH and DMSO-d(6). The coexistence of multiple conformations is established by the simultaneous observation of diagnostic NOEs. Control over stereochemistry of the central beta-turn permits generation of models for robust beta-hairpins and also for the construction of systems that may be used to probe helix-hairpin conformational transitions.

Amino Acid Sequence↗
PubMed1989

The noncompetitive blocker [(3)H]chlorpromazine labels segment M2 but not segment M1 of the nicotinic acetylcholine receptor alpha-subunit.

The membrane bound acetylcholine receptor from Torpedo marmorata was photolabeled by the noncompetitive channel blocker ]3H]chlorpromazine under equilibrium conditions in the presence of the agonist carbamoylcholine. The radioactivity incorporated into the AChR subunits was reduced by addition of phencyclidine, a specific ligand for the high-affinity side for noncompetitive blockers. The alpha-subunit was purified and digested with trypsin and/or CNBr and the resulting fragments fractionated by HPLC. Sequence analysis resulted in the identification of Ser-248 as a major residue labeled by [3H]chlorpromazine in a phencyclidine-sensitive manner. This residue is located in the hydrophobic and putative transmembrane segment M2 of the alpha-subunit, a region homologous to that containing the chlorpromazine-labeled Ser-262 in the delta-chain [1] and Ser-254 and Leu-257 in the beta-chain [2]. Extended sequence analysis of the hydrophobic segment M1 further showed that no labeling-occurred in this region.

Amino Acid Sequence↗
PubMed1986

A plasmid vector for cloning and expression of gene segments: expression of an HTLV-I envelope gene segment.

We describe a cloning-expression vector system for selecting DNA fragments containing open reading frames (ORFs) and expressing them as beta-galactosidase (beta Gal) hybrid fusion proteins. The plasmid vector, pWS50, utilizes the very strong and easily regulated bacteriophage lambda promoter pL, and the efficient translation initiation signals of the N-terminal segment of the lambda cII gene. Fused distally to and out of translational phase with cII is the E. coli lacZ gene, lacking its own transcriptional and translational initiating signals. A unique restriction enzyme site (NruI) is located between the upstream regulatory sequences and the lacZ gene, which provides a cloning site for the insertion of blunt ended DNA fragments. In addition, there are two other unique restriction sites (NheI and BamHI) located in this region which can also be used as closing sites. If a DNA fragment does not contain any translation termination codons (i.e., an ORF), and is inserted correctly into the vector, the translational reading frame between cII and lacZ can be restored. Colonies containing these recombinants can be easily screened as LacZ+ on lactose indicator media. The beta-galactosidase fusion proteins produced from the LacZ+ recombinants are identified on sodium dodecyl sulfate polyacrylamide gels by their large size and high level of production. To test the ORF cloning-expression system, a segment of the human T-cell lymphotrophic virus type I envelope gene was cloned and expressed at high levels. The envelope-beta Gal fusion protein was recognized by antibodies in serum from a patient with adult T-cell leukemia.

Antibodies, Neoplasm↗
PubMed1993

Synthesis of the segment (11-23) located in the first tandem repeat of plasma kallikrein: comparative binding studies of this and another segment (328-343) to high-molecular-mass kininogen.

The synthesis of porcine plasma kallikrein (pPK) segment (11-23), of sequence Phe-Phe-Arg-Gly-Gly-Asp-Val-Ser-Ala-Met-Tyr-Thr-Pro, present in the first tandem repeat sequence of the regulatory chain of PK, has been accomplished following the peptide fragments (5 + 4 + 4) condensation strategy in solution, as well as by fluorenylmethoxycarbonyl solid-phase chemistry. This and another synthetic PK segment of residues (328-343) present in the fourth tandem repeat sequence [Cys(ACM)-Ser-Leu-Arg-Leu-Ser-Thr-Asp-Gly-Ser-Pro-Thr-Arg-Ile-Thr-Tyr] and synthesized by a solid-phase method, were fully characterized by 1H nuclear magnetic resonance, fast atom bombardment mass spectrometry, amino acid composition and reversed-phase high-performance liquid chromatography. Proteolysis of these peptides by either rat PK (rPK) or trypsin resulted in cleavages between Arg decreases Gly for pPK (11-23) and between Arg decreases Leu and Arg decreases Ile for rPK (328-343). Kinetic studies revealed that for peptide pPK (11-23), the catalytic efficiency (kcat/Km) of rPK is congruent to 9-fold higher than that of trypsin, but for the other peptide, rPK (328-343), kcat/Km of trypsin is congruent to 49-fold higher than that of rPK. The facile cleavage of pPK (11-23) by rPK confirms the Arg13 decreases Gly14 position as the site of autolytic degradation of PK and also explains its special preference for Phe-Phe-Arg sequence.

Amino Acid Sequence↗
PubMed1991

Heart rate adjustment of the time-voltage ST segment integral: identification of coronary disease and relation to standard and heart rate-adjusted ST segment depression criteria.

To assess the effect of heart rate adjustment of the magnitude of the ST integral (ST-HR integral) on exercise test performance, the exercise electrocardiogram (ECG) of 50 clinically normal subjects and 100 patients with known or suspected coronary artery disease was analyzed. At matched specificity of 96% with standard ECG criteria (greater than or equal to 0.1 mV of additional horizontal or downsloping ST segment depression), an unadjusted ST integral partition of 16 microV-s identified coronary disease in the 100 patients with known or suspected disease with a sensitivity of only 41%, a value significantly lower than the 59% sensitivity of standard ECG criteria (p less than 0.01) and the 65% sensitivity of an ST depression partition of 130 microV (p less than 0.001). However, test performance of the ST integral was greatly improved by simple heart rate adjustment: at a matched specificity of 96%, an ST-HR integral partition of 0.154 microV-s/beat per min identified coronary disease in the 100 patients with a sensitivity of 90%, a value significantly greater than the 59% sensitivity of standard criteria and 65% sensitivity of ST depression criteria (each p less than 0.001) and similar to the 91% sensitivity of the ST-HR index and 93% sensitivity of the ST-HR slope (each p = NS). Comparison of receiver-operating characteristic curves confirmed the superior overall test performance of the ST-HR integral relative to the ST integral and ST segment depression, and demonstrated improved performance that was comparable with that of the ST-HR index and the ST-HR slope.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1976

Segmental renal vein renin assay and segmental nephrectomy for correction of renal hypertension.

Selective segmental renal vein catheterization was used to obtain venous blood samples for renin assay. With this technique a localized source of hypersecretion of renin was identified in 2 patients. Using samples from the main renal veins we found no significant difference in renin activity and, therefore, the etiology of the hypertension in these 2 patients would have been missed. Segmental nephrectomy resulted in a cure of the hypertension in both patients who were followed for a minimum of 14 months.

Adolescent↗
PubMed1998

Role and results of segmental allografts for acetabular segmental bone deficiency.

Acetabular reconstruction in both primary and revision hip arthroplasty often requires reconstruction of deficient acetabular bone stock. The exact role of allografts remains controversial. Published results of structural allografting are presented. Recent literature supports the use of segmental allografts for reconstruction of large segmental and combined defects.

Acetabulum↗