Biomedical subjects

L Blatt

Publications and source records attributed to L Blatt.

10 recordsLinked to original sources

PubMed2000

The effects of interferon on the expression of human papillomavirus oncogenes.

The effects of interferon (IFN)-alpha, IFN-beta and IFN-gamma on human papillomavirus (HPV) oncogene expression were studied in various cervical carcinoma cell lines containing integrated copies of either HPV type 16 or HPV type 18. The levels of E6 and E7 transcripts were examined 6 h and 30 h after treatment with IFN. In HeLa cells, all three classes of IFNs effected a decrease in the level of HPV-18 E6 and E7 transcripts. On the other hand, none of the IFNs altered the level of these transcripts in C-4II cells. Only IFN-gamma decreased the level of HPV-16 E6 and E7 transcripts in CaSki and HPK1A cells, while IFN-gamma actually increased the level of these transcripts in SiHa cells. This differential IFN regulation of HPV expression in various cervical cancer cell lines may account for the contradictory clinical results observed after treatment of cervical cancer with IFN.

Female↗

PubMed1999

Working with families in reaching end-of-life decisions.

This article provides the reader with a historical perspective of advance directives, the role of surrogate decision making, and the difficulties families encounter surrounding end-of-life decisions. Illustrated with a case study, it includes a framework for advanced practice nurses (APNs) and other health care professionals to assist families in reaching decisions. The APN can be instrumental in initiating an ethical discussion about resuscitation decisions and assist in dealing with conflicts. The APN can strive to make Do Not Resuscitate (DNR) discussions a consistent part of the hospital experience. It is hoped that the use of such a framework will improve care at the end of life.

Advance Directives↗

PubMed1998

Is there an optimal time to measure quantitative HCV RNA to predict non-response following interferon treatment for chronic HCV infection?

BACKGROUND/AIMS: Current criteria to predict sustained response for a patient with chronic hepatitis C virus during interferon treatment are not consistent. The aim of this study was to determine a reliable point in time to predict non-response to therapy, as a theoretical basis for early cessation of treatment. METHODS: Sera (-70 degrees C) from 66 patients treated with interferon (3 million units three times a week for 6 months) were assayed with a quantitative polymerase chain reaction (sensitivity < or =100 copies per milliliter). Evaluations were made at baseline, during treatment at weeks 1, 2, 4, 12, and 24, and at follow-up week 48. Biochemical response was defined using standard alanine aminotransferase criteria. Virologic response was defined as: sustained if loss of HCV RNA persisted through therapy and follow-up; relapse if HCV RNA became undetectable but reappeared during treatment or follow-up; and non-response if HCV RNA remained detectable during the study period. Alanine aminotransferase and HCV RNA results were analyzed at defined time intervals to determine a predictive value for non-response and sustained response. RESULTS: HCV RNA results are a more accurate predictor than alanine aminotransferase for both non-response and sustained response. Serum HCV RNA predicted non-response better than sustained response. The optimal time to predict non-response with serum HCV RNA was treatment week 12. CONCLUSIONS: Treatment week 12 results indicate that HCV RNA was a more accurate predictor for non-response than serum alanine aminotransferase. This prediction would have theoretically permitted stopping treatment for 75% of the patients in this study at treatment week 12 allowing an overall cost savings of 28%.

Adult↗

PubMed1998

Understanding nursing resources in intensive care: a case study.

OBJECTIVE: We describe the use of a measurement of nursing acuity in an ICU based on data from an integrated clinical and financial information system to shed light on the problem of a perceived change in the work of the unit. SETTING: A surgical-neurosurgical ICU in a teaching hospital with more than 800 beds. DESIGN: Changes in the work of nursing, defined by nursing acuity and by case mix and use of ancillary services in this unit for an 18-month period, were reviewed. RESULTS: The caseload was unpredictable. The lack of a systematic pattern of use of hospital resources burdened the nurses. CONCLUSION: For the first time at this institution, timely clinical and financial information has been brought together in an understandable format that can be used to explain trends and variances, to plan for the future, and to manage for cost and quality. The model for information management described here might serve other hospitals as well.

Connecticut↗

PubMed1996

Direct association of STAT3 with the IFNAR-1 chain of the human type I interferon receptor.

Based on the reports of the activation of the transcription factor known as STAT3 (for signal transducers and activators of transcription) or APRF (for acute phase response factor) by various cytokines, we investigated the possible role of STAT3 in type I interferon (IFN) receptor signaling. We show that STAT3 undergoes IFNalpha-dependent tyrosine phosphorylation and IFNalpha treatment induces protein-DNA complexes that contain STAT3. In addition, STAT3 associates with the IFNAR-1 chain of the type I receptor in a tyrosine phosphorylation-dependent manner upon IFNalpha addition. The binding of STAT3 to the IFNAR-1 chain occurs through a direct interaction between the SH2 domain-containing portion of STAT3 and the tyrosine-phosphorylated IFNAR-1 chain. Furthermore, tyrosine-phosphorylated STAT3 bound to the IFNAR-1 chain also undergoes a secondary modification involving serine phosphorylation. This phosphorylation event is apparently mediated by protein kinase C, since it was blocked by low concentrations of the protein kinase inhibitor H-7. The biological relevance of IFN activation of STAT3 is further illustrated by the finding that STAT3 is not activated by IFN in a cell line resistant to the antiviral and antiproliferative actions of IFN alpha but in which other components of the JAK-STAT pathway are activated by IFNalpha.

Base Sequence↗

PubMed1996

Comparative effects of interferon-consensus 1, interferon-alpha 2a, and interferon-beta 1b on HLA expression and lymphoproliferation: a preclinical model for treatment of multiple sclerosis.

Interferon-consensus 1 (IFN-Con 1) is a novel synthetic protein generated from codons for the most frequent amino acids in different type 1 IFNs. Compared with natural IFNs, IFN-Con 1 has been shown to have higher specific activity and antiproliferative activity and a higher ability to induce natural killer cells. In this study, the effects of IFN-Con 1 were compared with those of IFN-beta 1b and IFN-alpha 2a on HLA expression and lymphoproliferation. Human umbilical vein endothelial cells (HUVEC) express HLA class I but not class II molecules; however, both class I and class II molecules can be upregulated by IFN-gamma. IFN-Con-1 shared with IFN-beta 1b and IFN-alpha 2a the capacity to enhance HLA class I expression on HUVEC, alone and in combination with IFN-gamma. Although IFN-Con 1 had no effect on the basal expression of HLA class II molecules, it inhibited the IFN-gamma-induced class II expression on the HUVEC in a dose-dependent fashion. When this effect was compared among the three IFNs on mass basis, IFN-Con 1 activity was intermediate between that of IFN-beta 1b and IFN-alpha 2a. IFN-Con 1 also demonstrated an inhibitory effect on mitogen-driven lymphoproliferation similar to that of IFN-alpha 2a and exceeded that of IFN-beta 1b. The results indicate that IFN-Con 1 has immunomodulatory effects similar to those of IFN-beta 1b and IFN-alpha 2a, which could be relevant to the treatment of autoimmune and virus-mediated diseases.

Adjuvants, Immunologic↗

PubMed1992

Treatment of hairy cell leukemia with granulocyte colony-stimulating factor and recombinant consensus interferon or recombinant interferon-alpha-2b.

Patients with hairy cell leukemia and neutropenia (absolute neutrophil count less than 1.5 x 10(9)/L) were treated with recombinant granulocyte colony-stimulating factor (G-CSF) at doses of 3.6 and 7.2 micrograms/kg by daily subcutaneous injection, until normalization of neutrophil counts occurred. Patients then received either recombinant interferon-alpha-2b (r-IFN-alpha-2b) or a unique IFN, recombinant consensus IFN (rIFN-con-1), each given at doses of 10 micrograms/m2 subcutaneously three times a week, coupled with continued daily G-CSF therapy, for 3 months. After 3 months the G-CSF was discontinued; patients continued to take IFN for 1 year. All 10 patients responded to G-CSF with normalization of neutrophil counts within 2 weeks; the increase in neutrophil counts was greater in previously splenectomized patients. Four patients were treated with r-IFN-alpha-2b, and six were treated with rIFN-con-1. No patients developed recurrent neutropenia with the initiation of IFN therapy. Nine patients are evaluable for response to IFN. Five of six patients demonstrated hematologic improvement with rIFN-con-1, with two patients obtaining complete responses. All three patients receiving r-IFN-alpha-2b demonstrated hematologic improvement; one complete response was observed. Toxicities of both IFNs included influenza-like symptoms. We conclude that G-CSF can abrogate the myelosuppressive effects of IFN, and may be a useful adjunct to this therapy in neutropenic patients. We conclude that rIFN-con-1, the product of a synthetic gene, has activity in the treatment of hairy cell leukemia, and merits clinical investigation in other settings.

Drug Evaluation↗

PubMed1987

Dietary restriction: effects on radial maze learning and lipofuscin pigment deposition in the hippocampus and frontal cortex.

Previous studies have shown increased life span and decreased lipofuscin deposition in brain structures when both premature and young adult animals are calorically restricted of an otherwise nutritionally adequate diet. Three-months-old C57BL/6 mice were subjected to 12 months of caloric restriction (2 g/day), and subsequently exposed to a radial maze learning paradigm. Mice in the diet restriction group showed faster learning and higher asymptotic performance on the radial maze task, as well as lower lipofuscin deposition in the neurons of hippocampus and frontal cortex relative to control mice fed ad libitum. The results suggest that dietary restriction has effects on radial maze learning, and this improved behavioral performance was associated with significant reduction in lipofuscin pigment deposition in the neurons of hippocampus and frontal cortex.

Aging↗

PubMed1966

Occurrence of hydroxypyruvate-L-glutamate transaminase in Escherichia coli and its separation from hydroxypyruvate-phosphate-L-glutamate transaminase.

Blatt, L. (University of Wisconsin, Madison), F. E. Dorer, and H. J. Sallach. Occurrence of hydroxypyruvate-l-glutamate transaminase in Escherichia coli and its separation from hydroxypyruvate-phosphate-l-glutamate transaminase. J. Bacteriol. 92:668-675. 1966.-The formation of l-serine from hydroxypyruvate by a transamination reaction with l-glutamate has been demonstrated in extracts of Escherichia coli. The level of activity with hydroxypyruvate is approximately one-tenth that observed with hydroxypyruvate-phosphate in cell-free extracts. The transamination of hydroxypyruvate, but not hydroxypyruvate-phosphate, is inhibited by inorganic phosphate. No marked differences in the levels of activity with hydroxypyruvate were observed in extracts from bacteria grown under different conditions. Heat treatment of enzyme preparations at 65 C rapidly destroys the activity with hydroxypyruvate-phosphate, but not that with hydroxypyruvate. Fractionation of extracts with lithium sulfate and alumina Cgamma resulted not only in a 10-fold purification, but also in a complete separation of the two activities, thereby establishing that two different enzymes are involved in the transamination of hydroxypyruvate and hydroxypyruvate-phosphate. Hydroxypyruvate transaminase is present in two mutants that require serine for growth. The inability of hydroxypyruvate to replace the growth requirement for serine, even to a limited extent, was shown to be due to the inability of the bacteria to accumulate this compound actively.

Alanine↗

PubMedDate not supplied

Holistic care of the critically ill: meeting both patient and family needs.

Holistic care of the critically ill includes meeting the needs of both the patient and the patient's family. The critical care nurse needs to be prepared to deal with the family's special needs during a time of crisis, including making decisions about the withdrawal of life support. This article addresses such issues, and includes care of the family once technological support has been withdrawn and the patient is transferred from the Intensive Care Unit.

Adaptation, Psychological↗