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J Goldstein

Publications and source records attributed to J Goldstein.

At least 91 records · Page 5Linked to original sources
PubMed1997

Melatonin cycle in the fiddler crab Uca pugilator and influence of melatonin on limb regeneration.

Melatonin was measured over 24 hr in the eyestalks of Uca pugilator by means of radioimmunoassay; crabs were acclimatized either to a LD 12:12 photoperiod or constant darkness. A significant peak occurred at 13.00 hr in the LD 12:12 crabs. A photophase peak in melatonin has only been reported in one other species, also a crustacean. In constant darkness, two melatonin peaks occurred, one at 16.00 hr and the other 12 hr later; these results suggest that the melatonin cycle is a true circadian rhythm. HPLC with ultraviolet-visible detection was used to confirm the identity of melatonin immunoactivity. The influence of melatonin on regeneration of the walking legs was also examined: eyestalks were either removed or left intact, and limb bud length was measured every other day for at least 17 days in control and melatonin-treated crabs (60 microg ml(-1) seawater). Melatonin significantly increased the rate of limb regeneration in both eyestalk-intact and eyestalk-removed groups; this is contrary to results of regeneration studies in other phyla, in which similar melatonin concentrations inhibited regeneration.

Animals↗
PubMed1997

Carotid artery stenosis: optimization of CT angiography with a combination of shaded surface display and source images.

PURPOSE: To evaluate the accuracy of CT angiography of occlusive disease of the carotid arteries using three-dimensional surface-rendered images alone and in conjunction with display of axial source images. METHODS: Forty-eight symptomatic patients had conventional angiography followed by CT angiography within 24 hours. Images of 96 carotid arteries were acquired using contrast-enhanced spiral CT. Image postprocessing was performed on a free-standing workstation to produce 3-D shaded surface display (SSD) images. Two readers independently evaluated the CT angiographic (SSD) images and then reevaluated each case while simultaneously reviewing the SSD and axial source images. Digital subtraction angiograms were evaluated in a separate session and eventually compared with CT angiograms. All evaluations were performed under blinded conditions to control for reader bias. RESULTS: SSD images alone underestimated stenosis relative to angiograms whereas combined SSD and axial images did not. CONCLUSION: SSD angiograms in conjunction with the source images are better than SSD images alone in estimating the degree of stenosis in carotid artery disease.

Adult↗
PubMed1997

Partnerships.

Explore the source record for details and available documents.

Partnership Practice, Dental↗
PubMed1996

F(c)gammaRI-targeted fusion proteins result in efficient presentation by human monocytes of antigenic and antagonist T cell epitopes.

A major challenge for using native or modified T cell epitopes to induce or suppress immunity relates to poor localization of peptides to antigen presenting cells (APCs) in vivo. In this study, we demonstrate enhanced presentation of antigenic and antagonistic peptides by targeting them to the type I Fc receptor for IgG (F(c)gammaRI, CD64) on human monocytes. A Th epitope of tetanus toxoid, TT830, and the antagonistic peptide for TT830, TT833S, were genetically grafted into the constant region of the heavy chain of the humanized anti-CD64 mAb 22 and expressed as monovalent fusion proteins, Fab22-TT830 and Fab22-TT833S. These CD64-targeted peptides were up to 1,000- and 100-fold more efficient than the parent peptides for T cell stimulation and antagonism, respectively, suggesting that such fusion proteins could effectively increase the delivery of peptides to APCs in vivo. Moreover, the F(c)gammaRI-targeted antagonistic peptide inhibited proliferation of TT830-specific T cells even when APCs were first pulsed with native peptide, a situation comparable with that which would be encountered in vivo when attempting to ameliorate an autoimmune response. These data suggest that targeted presentation of antagonistic peptides could lead to promising Ag-specific therapies for T cell-mediated autoimmune diseases.

Amino Acid Sequence↗
PubMed1996

Characterization of recombinant alpha-galactosidase for use in seroconversion from blood group B to O of human erythrocytes.

Alpha-Galactosidase (alpha-GAL) purified from green coffee bean cleaves the terminal galactose residues from the surface of group B erythrocytes, thereby converting these cells serologically to group O cells. Such enzymatically converted red cells have been transfused into group A and O recipients as part of the first phase of FDA-approved clinical trials. Recently we expressed the recombinant alpha-GAL (r)alpha-GAL) in large quantities in a methylotrophic yeast strain Pichia pastoris and purified the protein to apparent homogeneity by chromatography on a macro prep S50 column. Purified (r)alpha-GAL, migrating as a single band of 41 kDa on a SDS-PAGE, appears to be identical to its native counterpart in specific activity (32 U/mg) and kinetic parameters (K(m) =0.363 mM and V(max) = 46.9 U/mg). Both enzymes demonstrate the same pH profile in the pH range from 2 to 9, with an optimal pH at 6.4 when tested with the substrate p-nitrophenol-alpha-D-galactopyranoside. Furthermore, as with its native counterpart, (r)alpha-GAL specifically cleaves alpha-linked terminal galactose residues from group B red cells without affecting other major antigens on the red cell surface. In addition, we developed a method for using RT-PCR to detect possible DNA contamination in the purified protein preparation, which is one of the concerns for in vivo studies. Thus, with a simple procedure for over-expression and purification of (r)alpha-GAL from P. pastoris culture, one can readily obtain the enzyme needed for large-scale sero-conversion of red cells.

ABO Blood-Group System↗
PubMed1996

Expression, purification, and characterization of recombinant alpha-N-acetylgalactosaminidase produced in the yeast Pichia pastoris.

alpha-N-Acetylgalactosaminidase (alpha NAGAL, EC 3.2.1.49) purified from chicken liver has been used in seroconversion of human erythrocytes. Blood group A, defined by the terminal alpha-linked N-acetylgalactosamine, can be cleaved in vitro by alpha NAGAL, resulting in the underlying penultimate blood group H (O) epitope structure. In order to produce sufficient quantities of recombinant alpha NAGAL (r alpha NAGAL) for such studies, we expressed the cDNA encoding chicken liver alpha NAGAL in Pichia pastoris, a methylotrophic yeast strain. The alpha NAGAL coding sequence was cloned into the EcoRI site of the vector pPIC 9 such that the protein was in the same reading frame as the secretion signal of yeast alpha-mating factor derived from the vector. After P. pastoris transformation, colonies were screened for high-level expression of r alpha NAGAL based on enzyme activity. As a result of methanol induction of high-density cell cultures in a fermentor, enzymatically active r alpha NAGAL was produced and secreted into the culture medium. The recombinant enzyme was purified over 150-fold by chromatography on a cation exchange column followed by an affinity column. Its homogeneity was confirmed by Coomassie blue-stained SDS-PAGE, Western blot, and N-terminal sequencing. The purified r alpha NAGAL has a molecular mass of approximately 50 kDa while its native counterpart has a molecular mass of 43 kDa. This discrepancy in size was eliminated by endoglycosidase treatment, suggesting that the recombinant protein was hyperglycosylated by the host P. pastoris cells. r alpha NAGAL was further characterized in terms of specific activity, pH profile, kinetic parameters, and thermostability by comparing with alpha NAGAL purified from chicken liver. The data presented here suggest that by overexpressing r alpha NAGAL in P. pastoris and purifying with affinity chromatography one can readily obtain the quantity of enzyme needed for seroconversion studies.

Amino Acid Sequence↗
PubMed1996

Alniditan in the acute treatment of migraine attacks: a subcutaneous dose-finding study. Subcutaneous Alniditan Study Group.

Alniditan is a new 5HT1D receptor agonist, belonging to a different chemical class from sumatriptan and other indole derivatives used or being developed for the treatment of acute migraine. In a multinational double-blind randomized parallel-groups dose-finding trial, alniditan was given subcutaneously in hospital to patients with migraine headache of moderate or severe intensity at doses of 0.8 mg (n = 44), 1.0 mg (n = 42), 1.2 mg (n = 46) and 1.4 mg (n = 39). Efficacy, tolerability and safety of each dose were compared with those of placebo (n = 41). At 2 h after injection, headache was absent or mild in 83% and 82% of patients receiving alniditan 1.2 and 1.4 mg respectively compared with 39% for placebo (p < or = 0.002). Complete relief from headache was achieved in 72% (1.4 mg). Time to onset of relief decreased with increasing alniditan dose, and there was a dose-dependent reduction in headache recurrence rate: 25% of patients receiving 1.4 mg had responded by 15 min and headache recurred within 24 h in only 16% of the patients who initially responded to alniditan 1.4 mg, significantly less than for placebo (p = 0.018). Alniditan was superior to placebo in reducing the associated symptoms of nausea, phonophobia and photophobia, and in increasing patients' functional ability. The use of rescue medication was reduced when compared with placebo, and up to 87% of patients said that they would use the drug again if available. No clinically relevant cardiovascular effects were seen, nor consistent changes in clinical laboratory findings. Adverse effects, mainly head pressure, paraesthesia, and hot flushes, were reported by 34% of placebo-treated patients and up to 70% of patients receiving alniditan, but all doses were very well tolerated and no clear relationship with dose was established. Comparison with published findings suggests that alniditan 1.4 mg sc may have advantages over sumatriptan 6 mg sc in providing complete relief from acute migraine headache, and may be associated with fewer headache recurrences within 24 h. Both of these suggestions warrant further and larger trials of alniditan in acute migraine.

Adult↗
PubMed1996

High-dose versus low-dose valproic acid as a prophylactic medication.

Valproic acid has been shown to be effective in migraine prophylaxis. Its method of action is believed to be the inhibition of gamma-aminobutyric acid transaminase. The therapeutic dose needed to prevent migraine headaches has been examined in several studies, yet the optimum dose has not been found. In this case report, valproic acid was given to a 24-year-old woman with chronic headaches at 1000 mg per day. Her headaches resolved for 2 months. She tapered herself off of the medication, and her headaches returned. She was restarted at 500 mg per day of valproic acid and again, her headaches resolved. She preferred being on the lower dose which she found as effective as the higher dose. Her case makes two interesting points. The first is that lower dosages of valproic acid may be as effective as higher ones in headache prophylaxis. The second is that more studies looking at dose ranges are needed to correlate effectiveness with daily requirements.

Adult↗
PubMed1996

"Put yourself in the skin of the child," she said.

Two Native American children were adopted by a non-Indian family. Following a legal challenge under the provisions of the Indian Child Welfare Act, the case became before both the United States Supreme Court and an Indian Tribal Court. In this paper we analyze the procedure and outcome of this transcultural adoption case from the point of view of the children involved and compare it with the intracultural "Baby Richard" case. Anna Freud believed that continuity of care is vital for each child's healthy growth and development. Transcultural adoptions highlight questions that characterize contested placements, whether or not they cross cultural boundaries and whether or not they place children across lines of race, color, religion, or national origin.

Acculturation↗
PubMed1996

A psychoeducational bereavement-support group for families provided in an outpatient cancer center.

BACKGROUND: Grief is a normal and highly personal reaction to loss. Bereavement care (individual and/or group) can assist family members and friends in coping with their feelings of grief, thereby reducing the possibility of complicated grief reactions. The families and significant others of patients who have died in settings other than a hospice do not automatically have the opportunity for bereavement follow-up. METHODS: An eight-session psychoeducational group that provided psychosocial support and information aimed at assisting in the bereavement process was initiated at an outpatient cancer center. It was led by a family therapist who was a member of a psychosocial services team. Family members and friends of recently deceased patients were invited to participate by letter and phone call. RESULTS: Seven people participated in at least one group session. Participants were asked to complete a face-valid follow-up questionnaire three months after completion of the group. CONCLUSIONS: Group members found the group experience beneficial, especially regarding the opportunity to talk with others who had experienced similar losses, learning about the reactions one would expect in the grieving process, and developing new strategies to deal with the grief associated with the loss.

Adaptation, Psychological↗
PubMed1996

Diagnosing and treating cytomegalovirus pneumonia in patients with AIDS.

Because cytomegalovirus (CMV) can be isolated from pulmonary secretions of human immunodeficiency virus (HIV)-infected patients without causing disease, its clinical significance as a cause of pneumonia in this patient population is frequently questioned. In a 22-month period, CMV pneumonia was diagnosed in 17 (8%) of 210 HIV-infected patients who underwent lung biopsy on the basis of microbiological and histologic criteria. The clinical presentations of these patients were nonspecific, including fever (100% of patients), shortness of breath (71%), cough (76%), and Pao2 of < 75 mm Hg (88%). A high correlation in the degree of viral burden in lung biopsy specimens was demonstrated by histologic examination, immunohistochemical analysis, and in situ hybridization. No other pulmonary pathogens were identified for nine patients, whereas other possible causes of pneumonia were present in eight: 11 patients had evidence of extrapulmonary CMV disease at presentation. Most patients initially responded to specific anti-CMV therapy; the overall mean survival +/- SD was 3.1 +/- 2.5 months. CMV should be considered as a possible cause of pneumonia in patients with advanced AIDS especially if CMV infection is documented at other sites.

AIDS-Related Opportunistic Infections↗
PubMed1996

A putative poststreptococcal case of OCD with chronic tic disorder, not otherwise specified.

A 12-year-old girl presented with an atypical, recurrent, increasingly treatment-resistant case of obsessive-compulsive disorder and chronic tic disorder associated with profound separation anxiety, learning difficulty, and intermittent upper respiratory symptoms. In addition to detailed reviews of history and findings from many clinical caretakers from the prior 7 years, current pediatric, psychiatric, neuropsychological, neuroimaging, and clinical laboratory data were also available. Treatment options were considered from multiple perspectives: psychoanalytically oriented psychotherapy, conventional pharmacotherapy, family interventions, cognitive-behavioral therapy, and learning-supportive strategies. Psychological, neuropsychiatric, and neuroimmunological formulations of etiology were considered. Subsequent treatments included supportive psychotherapy, neuroleptic augmentation of selective serotonin reuptake inhibitors, prophylactic penicillin, and a course of six sessions of plasmapheresis over a 2-week period. The case raises questions for ongoing consideration that juxtapose dynamic, neuropsychiatric, and neuroimmunological perspectives.

Antibiotic Prophylaxis↗
PubMed1996

Immunohistochemical study of pancreatic neuroendocrine tumor in Panthera tigris tigris.

The histological and immunohistochemical characteristics of a case of pancreatic neuroendocrine tumor are described in a 14-yr-old female Bengal tiger (Panthera tigris tigris) housed at the New Biblical Zoo of Jerusalem, Jerusalem, Israel, 1994. The neoplastic cells were immunohistochemically negative for insulin and glucagon, slightly positive for neuron-specific enolase, moderately positive for serotonin and somatostatin, and markedly positive for chromogranine A and gastrin. This is the first documentation of a pancreatic neuroendocrine tumor in the tiger.

Animals↗
PubMed1996

A chimeric streptokinase with unexpected fibrinolytic selectivity.

Chimeric 59D8-SK was designed to confer fibrin-selectivity to streptokinase by fusion of the Fab fragment of anti-fibrin antibody 59D8 to the N-terminus of streptokinase (SK: Ile1-Lys414). It was expressed in a mouse hybridoma cell line and purified by affinity chromatography on a 59D8-antigen column. Chimeric 59D8-SK is a disulfide-linked heterodimer composed of an antibody light chain (Mr 27,000) and a N-glycosylated chimeric heavy chain (M(r) 90,000). The fibrin targeting by 59D8 increased plasma clot lysis by 2-fold, but connecting 59D8 to SK has provided 59D8-SK several unique properties: (i) 59D8-SK activated human Glu-plasminogen with a significant lag period that coincided with limited proteolysis of 59D8-SK similar to that observed for wild-type SK. In a kinetic study, both gave very similar kinetic parameters for the activation of Glu-plasminogen even though 59D8-SK was N-glycosylated in its SK portion; (ii) 59D8-SK was relatively inactive in human plasma, compared to SK, but it became activated in the presence of clots; (iii) 59D8-SK lysed clots slowly but completely whereas SK lysed clots rapidly but incompletely. Even though the mechanism behind these new properties is not fully understood, they are characteristics of a second-generation plasminogen activator.

Animals↗
PubMed1995

High-level expression and purification of coffee bean alpha-galactosidase produced in the yeast Pichia pastoris.

alpha-Galactosidase isolated from coffee beans cleaves the terminal alpha-galactose residues from oligosaccharide chains on blood group B red cells, thus generating group O cells. Such enzymatically converted red cells not only maintain full erythrocyte integrity and viability in vitro, but also demonstrate immune tolerance and a normal life span in vivo. In order to produce large quantities of recombinant alpha-galactosidase for use in the study of blood-type conversion, we subcloned the cDNA coding for coffee bean alpha-galactosidase into the EcoRI site of the vector pPIC9 in order to express the enzyme in Pichia pastoris, a methylotrophic yeast strain. After P. pastoris transformation, colonies were screened for high-level expression of alpha-galactosidase, based on enzyme activity. In order to increase enzyme production, the growth conditions in the shake flask culture and fermentor culture were optimized. Under the conditions applied, biologically active alpha-galactosidase was produced and secreted into the culture medium at a level of approximately 0.4 g per liter of the fermentor culture. The protein was purified to apparent homogeneity by a simple chromatography procedure, as suggested by a single band of 41 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Its homogeneity was further confirmed by chromatofocusing and N-terminal sequencing. P. pastoris appears to be the choice as host for the large-scale production of recombinant alpha-galactosidase used for blood type conversion.

Amino Acid Sequence↗
PubMed1995

Activation of signal transducer and activator of transcription-3 (Stat3) expression by interferon-gamma and interleukin-6 in hepatoma cells.

Signal Transducer and Activator of Transcription 3 (Stat3) is a latent protein activated in response to various cytokines and growth factors. It is believed that Stat3 is a key signaling molecule involved in the regulation of acute phase gene expression by interleukin 6 (IL-6) in hepatocytes. We report that both IL-6 and interferon gamma (IFN gamma) up-regulate the expression of Stat3 on both mRNA and protein levels in rat and human hepatoma cells. The effect of IL-6 and IFN gamma on Stat3 mRNA expression was time- and dose-dependent. Other factors, including IL-1, TNF alpha, EGF, Dexamethasone and PMA, did not have any effect on Stat3 mRNA expression. Moreover, we show that the rapid induction of Stat3 expression by IL-6 and IFN gamma was independent of ongoing protein synthesis, suggesting regulation by Stat3 and Stat1, respectively.

Acute-Phase Proteins↗
PubMed1995

Expression of c-fos and c-jun in rat retina following protracted illumination.

Illumination produces degeneration of outer photoreceptor segments, a phenomenon that may be reversed after a period of darkness. Neuronal expression of the immediate early genes (IEGs) c-fos and c-jun, both recognized as proto-oncogenes, has been reported after stimulation of different regions in the central nervous system (CNS). We performed a sequential study on Fos and Jun immunoreactivity to investigate the role of IEGs following 8 days of continuous illumination in 30-35-day-old Wistar rats. Retinas were fixed by perfusion in 4% paraformaldehyde, after a period of illumination followed by 0, 2, 7, 10 and 20 days in total darkness. Cryostat sections were immunocytochemically stained using antibodies to Fos and Jun. Fos and Jun immunoreactivities were detected in all photoreceptors evaluated, peaking in nuclei of rats kept in total darkness for 2 days, and becoming negative as from 7 days. Increases in c-fos and c-jun products during the darkness period may play a role in triggering molecular events participating in plastic changes in photoreceptors and/or in the protection for oxidative damage cause by free radicals induced by light irradiation.

Animals↗