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Biomedical subjects

P Levine

Publications and source records attributed to P Levine.

At least 19 recordsLinked to original sources

Substance use among women at risk for HIV infection.

This article reports results from a survey of culturally diverse women at risk for HIV infection in south Florida. Data concerning their substance use and its association with HIV risk behaviors are presented. Results indicate levels of consumption which exceed expectations based on general estimates of female substance use. Further, substance use was associated with specific behaviors and lifestyles which placed the women at increased risk for HIV infection.

Adult

Patterns of chromosomal breakpoint locations in Burkitt's lymphoma: relevance to geography and Epstein-Barr virus association.

We have examined, by Southern blotting, the patterns of chromosomal breakpoint locations in 55 cases of Burkitt's lymphoma (BL) with respect to geography and Epstein-Barr virus (EBV) association. We have confirmed the association between chromosome 8 breakpoint and geography: 74% of endemic (eBL) but only 9% of sporadic BL (sBL) had breakpoints outside the HindIII fragment encompassing the c-myc gene (P2 less than .00001). Conversely, not only did 91% of sBL manifest a rearranged HindIII fragment, but at least 56% of these cases, in contrast to 17% of eBL cases, had a breakpoint within the first exon or intron of c-myc (P2 less than .004). Breakpoints outside the switch mu (S mu) region (ie, the HindIII fragment encompassing S mu) on chromosome 14 were twice as common overall (73%) as those within S mu (27%), but in the 15 tumors with S mu breakpoints, 13 (87%) had a rearranged c-myc gene. Breakpoints outside the HindIII fragment encompassing c-myc on chromosome 8 were predominantly associated with non-S mu breakpoints on chromosome 14 (85%) and this was the combination most frequently associated with eBL (65%; 6% of sBL, P2 less than .00001). In sBL, the most frequent breakpoint combination was a rearranged c-myc gene with a non-S mu breakpoint (63%; 13% of eBL). Twenty-eight percent of sBL and 13% of eBL had breakpoints both within c-myc and within S mu. EBV DNA was present in 19 of 20 tumors with breakpoints outside c-myc, in none of 7 with a breakpoint in the immediate 5' region of c-myc, in 4 of 5 tumors with breakpoints in the first exon, and in 7 of 12 tumors with breakpoints in the first intron. These data suggest that the pathogeneses of eBL and sBL differ with regard to the mechanism of c-myc deregulation, and probably also with regard to the state of differentiation of the target cell for malignant transformation. We have formulated a testable hypothesis regarding the potential role of EBV in pathogenesis: that it is required to contribute to the deregulation of c-myc in the presence of some, but not all, types of c-myc damage arising from the chromosomal translocations.

Blotting, Southern

Monoclonal antipeptide antibodies against amino acid residues 1101-1106 of human C4 distinguish C4A from C4B.

Comparison of amino acid sequences of the alpha-chain fragment of human C4, C4d, has shown C4A- and C4B-specific sequences at residues 1101-1106 in which the aspartic acid-histidine substitution at position 1106 may be related to the amide and ester bond forming properties of these molecules. Peptides containing twelve amino acid residues of the C4A- or C4B-specific sequences were synthesized and injected into female Balb/c mice. Serum from 2 mice, one immunized with the C4A-specific peptide and the other with the C4B-specific peptide, gave strong isotype-specific responses in an enzyme-linked immunosorbent assay against affinity-purified C4A3 and C4B2B1. Spleen cells from these mice were fused with the mouse myeloma SP2/0-Ag 14, and two cloned cell lines, AII-1 and BII-1, were established from hybrids. Enzyme-linked immunosorbent assay and western blotting of monoclonal antibodies AII-1 and BII-1 show that the former reacts with the C4A but not with the C4B alpha-chain and the latter with C4B but not with the C4A alpha-chain. Furthermore, immunoblotting of C4 allelic variants showed that AII-1 reacted with all C4A allotypes tested, including A6, A4, A3 and A2, whereas BII-1 reacted with all C4B allotypes tested, including B5, B3, B2, and B1.

Amino Acid Sequence

AIDS knowledge and risk behaviors among culturally diverse women.

This article reports results from a survey of women at risk for HIV infection. The sample (n = 620) included black (50.6%), white (28.7%), Hispanic (13.4%), and Haitian (5.0%) adult women from south Florida. Data concerning their AIDS knowledge, prevalence of risk behaviors, and perceived vulnerability are presented. Results indicate differences in certain knowledge areas and risk behaviors by race/ethnicity and a consistent incidence of unprotected sex with their main partners across all racial/ethnic groups.

Acquired Immunodeficiency Syndrome

Effect of prophylactic antibiotics in radical head and neck surgery.

One hundred major head and neck operations performed on 77 patients were evaluated regarding the effectiveness of an aminoglycoside and cephalosporin antibiotic combination given prophylactically to prevent postoperative infection. The postoperative infection incidence was 6%, significantly lower than that reported in similar series where no antibiotics were used. The addition of the aminoglycoside did not appear to provide any additional protection compared with the use of cephalosporin alone.

Aminoglycosides

Forssman-like antibody levels in sera of patients with lung cancer.

Sera of normal individuals or patients with lung cancer were assayed for Forssman-like antibody by a quantitative and specific method using ethylenediaminetetraacetate-containing buffer to inactivate complement in the test serum. It was shown that although Forssman-like antibody levels were distributed widely, (a) the levels of young (20 to 45 years of age) normal subjects of Blood Groups A and AB were lower than those of Blood Groups O and B, (b) the levels of old (60 to 80 years of age) normal subjects were lower than those of young normal subjects of Blood Groups O and B, and (c) the levels of old lung cancer patients were lower when compared to age-matched normal individuals of their blood group.

ABO Blood-Group System

Self-nonself concept for cancer and diseases previously known as "autoimmune" diseases (illegitimate transferases/plasma exchange).

The illegitimate glycosphingolipid antigens of the P blood group system and of the Forssman (Fs) tissue antigen in adenocarcinoma which are foreign to the host suggest the self-nonself concept which applies also to numerous other diseases such as rheumatoid arthritis, lupus, gluomerulonephritis, and idiopathic acute hemolytic anemia. In the presence of the glycosphingolipid antigens such as ABO, P, and Fs, the normal serum of the homozygote recessive precursor contains antibodies for the missing antigen(s). The expected antibody to the Fs antigen was present in about 75% of normal men and women. In cancer sera, the incidence of anti-Fs was decreased to about 35-40%. On testing the normal population anti-Fs was present in 90% of the sera in the youngest group, and this value gradually diminished in the older groups; the incidence of the antibody in the 70-year age group was to about 60%. The rate of loss of anti-Fs with increasing years appears to parallel the gradual loss of anti-A and anti-B isoagglutinin titers. This phenomenon may be associated with the gradual diminution of protein synthesis with aging or the continuous accumulation of soluble immune complexes in the serum, or both. It is suggested that the self-nonself concept is also the basis for the pathogenesis of rhematoid arthritis, lupus erythematosus, idiopathic acute hemolytic anemia, and numerous other conditions classified as "autoimmune" diseases. Some of these diseases are induced by viruses or drugs or both. When a virus or drug attaches itself to the membrane of a tissue cell, the self is converted to nonself which, in rheumatoid arthiritis, alters its self Ig to nonself Ig.

ABO Blood-Group System

Preliminary evaluation of the histotoxicity and radiopacity of lead-containing elastic impression materials.

Severe reactions can be caused when elastic impression materials are trapped beneath soft tissues. To develop a rank order of severity of responses, a series of these materials was injected beneath the oral mucosa of a baboon. Alginate and polysulfide rubbers containing lead peroxide produced severe reactions; hydrocolloid, polysulfide without lead, silicone, and polyether produced more mild reactions. The more toxic materials proved to be more radiopaque than the others. Tests for foreign body toxicity should be made a part of future specifications for these materials, and the use of toxic ingredients should be reduced as much as possible. These materials should be made opaque to X rays and of a different color than those of soft or hard tissues.

Abscess

Clinical evaluation of EBV serology in American patients with nasopharyngeal carcinoma.

There is now extensive immunological, biological and biochemical evidence to support a possible etiological relationship between EBV and NPC in patients from different geographical locations. Besides providing information on the question of etiology, the results from immunological investigations suggest that antibodies to some of the EBV-associated antigens might also be of clinical importance in the diagnosis and prognosis of NPC. To determine the possible clinical application of EBV serology to American NPC, sera from patients seen at the Mayo Clinic and the National Institutes of Health were examined for antibodies to EBV-associated antigens in an effort to identify those parameters which most reliably distinguish NPC from other types of cancer. The results show that high antibody titres to EBV-induced EA and the presence of antibody to EBV antigens in the IgA immunoglobulin fraction were the two most specific discriminating parameters, although neither was infallible. These findings are discussed in relation to future studies that are needed in order to determine the potential clinical value of EBV serology to the diagnosis and prognosis of NPC.

Antibodies, Viral

Hemophilic arthropathy of the foot and ankle.

The major deformities in hemophilic arthropathy of the foot and ankle fall into the three groups of equinus, varus, and cavus. These pathologic positions develop through a repetitive pattern of intra-articular and intramuscular bleeding within the area of the distal calf, foot, and ankle. Appropriate infusion therapy with factor VIII concentrate and factor IX concentrate plus splinting, bracing, and logical rehabilitative maneuvers can delay or prevent the advent of permanent deformity. The actual articular damage seems to be directly related to the release of digestive enzymes from leukocytes, synovial cells, and other blood products. These pathologic mechanisms appear to be similar to those recently described in explaining joint destruction in rheumatoid and degenerative arthritis. The indication for certain reconstructive orthopedic procedures in these situations are given and case examples provided. Total joint replacement in the area of the foot and ankle in hemophilia has been considered for certain patients by the authors but not attempted as yet.

Adolescent