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N N Teng

Publications and source records attributed to N N Teng.

At least 19 recordsLinked to original sources
PubMed1995

Human CD5+ B lymphocytes (B-1 cells) decrease in peripheral blood during pregnancy.

Pregnancy is a unique immunologic state where a natural homeostasis exists between antigenically different tissues. Several earlier studies have addressed the fluctuations in the number and/or function of lymphocytes, including B cells during pregnancy, but changes within the subsets of B lymphocytes, conventional (CD5-) and B-1 (CD5+), have not been addressed. Here we demonstrate that the frequency of B-1 cells decreases dramatically during pregnancy, whereas the frequency of conventional B cells remains relatively constant. The missing B-1 cells return to pre-pregnancy levels 8-10 weeks after parturition. The polyreactive autoantibodies secreted by B-1 cells have been implicated in autoimmunity and immune regulation. The possible role of B-1 cells during pregnancy will be discussed in that context.

Adult↗
PubMed1994

FACS analysis of peritoneal lymphocytes in ovarian cancer and control patients.

In this study different lymphocyte populations in the malignant ascites of 10 patients with ovarian carcinoma and in the peritoneal fluid of 8 control patients (tubal ligation and benign conditions) were analyzed. A panel of monoclonal antibodies against the CD markers of lymphocytes was used to stain different populations and the cells were analyzed on a FACS II (fluorescence-activated cell sorter). The mean percentage of B lymphocytes in the peritoneal cavity of the OVCA patients was 0.18 +/- 0.5% and in the control patients 0.05 +/- 0.07%. There was no significant difference between the two groups. In the OVCA group and in the controls the percentage of T lymphocytes (CD5+) was 23.5% and 17.1% respectively with no significant difference between the groups. These results indicate that B lymphocytes are not present in the human peritoneal cavity. The small numbers of B cells found in this study could be due to contamination with peripheral blood. The human peritoneal cavity contains a cell population which differs from that present in peripheral blood. Significant numbers of B lymphocytes have been reported in the peritoneal cavity of mice. The difference between the lymphocyte population of the human peritoneal cavity and that of rodents implies that data on characterization and function of B lymphocytes in the mouse peritoneal cavity would not be applicable to humans.

Ascitic Fluid↗
PubMed1993

Human antilipid A monoclonal antibodies bind to human B cells and the i antigen on cord red blood cells.

We describe two independently derived human mAb, A6(H4C5) and 216, initially selected for their reactivity to the lipid A domain of bacterial LPS, which also react with the following Ag: the i Ag present on cord RBC, a ligand on human B lymphocytes, and to certain autoantigens, defining these mAb as polyreactive. Both mAb have specific affinity for a carbohydrate epitope consisting minimally of a disaccharide with an acyl substitution at the 2-carbon position. Structural examination of the diverse Ag recognized by the two antibodies reveals the presence of this carbohydrate structure required for antibody binding. A6(H4C5) and 216 are IgM in isotype, but differ in their L chain expression. Molecular analysis shows that both the mAb are encoded by a highly conserved VH4 gene, designated VH4-21. This gene encodes a number of autoantibodies, particularly cold agglutinins. Specific recognition of lipid A and of a carbohydrate epitope on B lymphocytes by the two human mAb suggests a dual function for the highly conserved VH4-21 gene in antibacterial response and in B cell development and regulation.

Agglutinins↗
PubMed1992

Critical reassessment of second-look exploratory laparotomy for epithelial ovarian carcinoma. Minimal diagnostic and therapeutic value in patients with persistent cancer.

From 1979 to 1984, 88 women with epithelial ovarian cancer were treated with surgery and chemotherapy, achieved a clinical complete response, and then had "second-look" exploratory laparotomy to assess the pathologic status of their disease. Persistent cancer was found in 50 (57%) patients: 34 of 50 (68%) had gross tumor, which was larger than 2 cm in 12 (24%) and smaller than 2 cm in 22 (44%), and 16 (32%) had microscopic disease. Salvage therapy was as follows for these patients: whole abdominal irradiation, 29 (58%); chemotherapy, 17 (34%); intraperitoneal chromic phosphate, 1 (2%); and no further therapy, 3 (6%). With a follow-up time of 4 to 8 years, 7 (14%) patients are alive without evidence of cancer, 7 (14%) are alive with disease, 35 (70%) are dead of disease, and 1 (2%) has died of treatment complications. At 5 years, the relapse-free rate was 18% and the survival rate was 25%. Seventy-two parameters of suspected prognostic significance and 64 potential sites of tumor involvement were correlated with survival in a univariate analysis. The factors favorably affecting survival included the following: lower grade; microscopic tumor versus gross disease at second-look laparotomy; removal of the uterus; removal of the omentum; pelvic and paraaortic lymph node biopsy; negative results of a right diaphragm biopsy; and radiation therapy at Stanford University Medical Center, Stanford, California. There was no survival advantage for whole abdomen irradiation compared with chemotherapy or for the patients who had their disease successfully debulked at second-look laparotomy. The above factors and others were evaluated by multivariate regression. The best model (P = 0.000004) for predicting survival included largest tumor mass (P = 0.0002), operative blood loss (P = 0.002), perioperative blood transfusion (P = 0.003), and grade (P = 0.004). The detection of persistent ovarian cancer by second-look exploratory laparotomy should identify a subgroup of patients whose conditions can be salvaged by a second-line therapy. Unfortunately, that subgroup is small (8%) and an effective salvage therapy remains to be identified.

Combined Modality Therapy↗
PubMed1992

Human monoclonal antibody recognizing an antigen associated with ovarian and other adenocarcinomas.

MS2B6, a human monoclonal antibody derived from a patient with advanced ovarian cancer, has been used to study the distribution and characteristics of its target antigen. The MS2B6 antigen was detected by immunoperoxidase studies in 41 of 41 epithelial ovarian cancers and in the majority of nonovarian adenocarcinomas. Among normal tissues the MS2B6 antigen was found in the adult epithelia of the fallopian tube, endometrium, endocervix, colon, bronchus, breast, sweat duct, and large renal ducts. No detectable antigen was found in peritoneal epithelia, tissue stromal cells, spleen, thymus, or blood-borne cells. Immunoblotting analysis showed that the MS2B6 epitope resides on polypeptides of 38, 44, and 60 kd. The cellular location of the MS2B6 antigen was studied with immunoperoxidase and immunofluorescent staining and immunoelectronmicroscopy of ovarian cancer ascites tumor cells. The results suggest that in ascites tumor cells the MS2B6 antigen is located in a layer of the peripheral cytoplasm beginning just below the cell membrane. MS2B6 may be useful as an imaging or therapeutic agent.

Adenocarcinoma↗
PubMed1992

The ontogeny and functional characteristics of human B-1 (CD5+ B) cells.

We demonstrate that, on average, greater than 90% of B lymphocytes in fetal spleen express CD5 at gestational ages of 17-23 weeks. Similarly, CD5+ B cells (B-1 cells) are the major B cell subset in umbilical cord blood. These findings depend on the optimization of fluorochrome conjugated anti-CD5 reagents for multiparameter fluorescent-activated cell sorter (FACS) analysis. From infancy through childhood the percentage of B-1 cells gradually diminishes in both spleen and peripheral blood. Stable adult levels, 25-35% of the total B cell population, are reached in late adolescence. The decrease in the percentage of B-1 cells in spleen is accompanied by an increase in conventional (CD5-) B cells, keeping the percentage of total B cells per mononuclear cells relatively constant. In contrast, in peripheral blood, the concentration of both B-1 cells and total B cells decreases, while T cells increase. At the functional level, we show that polyreactive IgM autoantibodies are produced by FACS-sorted CD5high B cells, but not by CD5- B cells from adolescent spleen. In contrast, fetal splenic CD5high and CD5- B cells appear functionally uniform, both producing IgM autoantibodies that are typical of B-1 cells. The apparent level of CD5- B cells in fetal spleen, on average 10% of total B cells, may still result from limitations of our reagent. The prominence of B-1 cells in fetal spleen and cord blood, the gradual reduction of B-1 cells with increasing age, and its characteristic repertoire, all suggest a role for this cell type in immunologically immature hosts.

Adolescent↗
PubMed1992

Adenocarcinoma-reactive human monoclonal antibody MS2B6 defines an antigen in simple glandular epithelium.

A human monoclonal antibody (MAb), MS2B6, produced from splenocytes isolated from a patient with advanced papillary serous cystadenocarcinoma of the ovary, defines a unique human tumor-associated antigen. This antigen, EA2B6 (epithelial antigen 2B6), is expressed in a tissue-restricted manner on cultured and fresh human adenocarcinomas and some normal glandular epithelial tissues. EA2B6 is a 38-48 kD protein antigen that co-fractionates with the nuclear matrix-intermediate filament scaffold of simple glandular epithelial tissues. EA2B6 is a molecule with restricted solubility, and in vitro antigen-antibody binding is dependent on the antigen being presented on a solid support. To determine if EA2B6 is a cytokeratin, competition studies were undertaken with several cytokeratin-specific murine monoclonal antibodies. None of these antibodies inhibited the binding of human MAb MS2B6 to partially purified EA2B6. Less than 1% of HT29 colon adenocarcinoma cells and fresh ovarian adenocarcinoma ascites cells express EA2B6 on their surface. The majority of EA2B6 is intracellular. Because of the restricted tissue distribution of this antigen and stability of the antibody, we believe MS2B6 is a good candidate for MAb-mediated diagnosis and therapy of human adenocarcinomas.

Adenocarcinoma↗
PubMed1991

Treatment of gram-negative bacteremia and septic shock with HA-1A human monoclonal antibody against endotoxin. A randomized, double-blind, placebo-controlled trial. The HA-1A Sepsis Study Group.

BACKGROUND: HA-1A is a human monoclonal IgM antibody that binds specifically to the lipid A domain of endotoxin and prevents death in laboratory animals with gram-negative bacteremia and endotoxemia. METHODS: To evaluate the efficacy and safety of HA-1A, we conducted a randomized, double-blind trial in patients with sepsis and a presumed diagnosis of gram-negative infection. The patients received either a single 100-mg intravenous dose of HA-1A (in 3.5 g of albumin) or placebo (3.5 g of albumin). Other interventions, including the administration of antibiotics and fluids, were not affected by the study protocol. RESULTS: Of 543 patients with sepsis who were treated, 200 (37 percent) had gram-negative bacteremia as proved by blood culture. For the patients with gram-negative bacteremia followed to death or day 28, there were 45 deaths among the 92 recipients of placebo (49 percent) and 32 deaths among the 105 recipients of HA-1A (30 percent; P = 0.014). For the patients with gram-negative bacteremia and shock at entry, there were 27 deaths among the 47 recipients of placebo (57 percent) and 18 deaths among the 54 recipients of HA-1A (33 percent; P = 0.017). Analyses that stratified according to the severity of illness at entry showed improved survival with HA-1A treatment in both severely ill and less severely ill patients. Of the 196 patients with gram-negative bacteremia who were followed to hospital discharge or death, 45 of the 93 given placebo (48 percent) were discharged alive, as compared with 65 of the 103 treated with HA-1A (63 percent; P = 0.038). No benefit of treatment with HA-1A was demonstrated in the 343 patients with sepsis who did not prove to have gram-negative bacteremia. For all 543 patients with sepsis who were treated, the mortality rate was 43 percent among the recipients of placebo and 39 percent among those given HA-1A (P = 0.24). All patients tolerated HA-1A well, and no anti-HA-1A antibodies were detected. CONCLUSIONS: HA-1A is safe and effective for the treatment of patients with sepsis and gram-negative bacteremia.

Antibodies, Monoclonal↗
PubMed1991

Quantitative protein changes in metastatic versus primary epithelial ovarian carcinoma.

Primary and metastatic ovarian carcinomas from six patients were obtained during primary exploratory laparotomy. Tumor cells were synthetically radiolabeled with [35S]methionine. Radiolabeled cellular proteins of the primary and metastatic cells were examined by two-dimensional polyacrylamide gel electrophoresis followed by autoradiography. Computer assisted analysis of the resultant autoradiograms revealed that the amounts of only two proteins, p35 and p36, were consistently and significantly decreased in the metastatic tumor cells. No other consistent differences in protein synthesis between primary and metastatic tumors were detected.

Down-Regulation↗
PubMed1991

Modified posterior exenteration for ovarian cancer.

The operative description of a modified posterior exenteration along with operative findings, other operative procedures, postoperative course, and follow-up information are presented for 47 patients (37 primary cytoreduction, ten secondary cytoreduction). All had stage IIIC or IV epithelial ovarian cancer with pelvic disease encasing the reproductive organs, pelvic peritoneum, cul-de-sac, and sigmoid colon. In addition to modified posterior exenteration, all patients had multiple other procedures performed as part of the cytoreductive efforts. Forty-five (95.7%) had optimal (less than 2 cm) cytoreduction and 18 (38.3%) had complete cytoreductive surgery. Thirty-four patients were ultimately rendered continent of feces (25 primarily and nine after colostomy reversal). Nine patients (19.1%) had serious morbidity and one (2.1%) died postoperatively. The median follow-up for those undergoing primary cytoreduction was 13.3 months (6-84). Nineteen (51.4%) were alive at the time of writing, 16 (43.2%) were dead, and two (5.4%) were lost to follow-up. Modified posterior exenteration effectively removes all visible pelvic disease with acceptable mortality. Hence, even patients with the most advanced cases of ovarian cancer may attain optimal cytoreduction and become ideal candidates for adjunctive therapy, with improved survival or a chance for cure.

Adult↗
PubMed1991

Gynecologic factors in sexual dysfunction of the older woman.

Older women may experience sexual dysfunction due to many different causes. Some problems related to menopausal hormonal change may be easily treated with estrogen supplements. Other problems involve intricate interpersonal relations between the woman and her sexual partner and may require a combination of medical therapy and sexual counseling. Gynecologic cancer and cancer treatments are often accompanied by problems in sexual functioning. These problems may then impair relations and self-image, leading to a vicious circle of deteriorating social function. Some recommendations for the clinician follow. The clinician should maintain an attitude of openness to the possibility of sexual concerns in older women. Such concerns should be taken seriously and should not be dismissed as part of aging. Routine periodic health examinations can include a question such as "Do you have any concerns about your sexual life that you would like to discuss?" In follow-up visits for procedures with a high likelihood of causing sexual dysfunction, questions that would open the door to a discussion of sexuality should be asked. Sexual dysfunction should be recognized as a couple-oriented phenomenon. A woman's anxiety about her appearance, postoperative depression, or dyspareunia may be perceived by her partner as a sexual rejection and may initiate a cycle of decreasing contact or may even lead to erectile dysfunction. Sexual counseling should include both partners. When a surgical procedure that will probably have an impact on sexual function is contemplated, provide the patient and her partner with advance counseling. Descriptions of surgery should not be simply a statement of body parts to be removed but should specifically address the anticipated sexual effects. Counseling should include a description of basic anatomy and function of the genital organs. Illustrations and appropriate demonstration during the physical examination should be used to ensure the patient's understanding. Descriptions should be accurate without being either frightening or falsely reassuring. The patient should be counseled about the benefits of including her partner in discussions. Then, when possible, the sexual partner of the patient should be invited to sessions of advance counseling on contemplated procedures. Clinicians should remain open to the possibility that the sexual partner will be a nontraditional one, e.g., an unmarried male partner or another woman. The clinician should be alert to remediable causes of dysfunction. For example, decreased vaginal lubrication may be managed with use of water-soluble lubricants.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMed1990

Prospective randomized trial of topical alpha-interferon (alpha-interferon gels) for the treatment of vulvar intraepithelial neoplasia III.

Twenty-one patients were prospectively randomized into a blinded double-armed crossover study comparing alpha-interferon (alpha-IFN, 10(6) IU in a 3.5% aqueous methylcellulose base) with and without 1% nonoxynol-9. Nine and twelve patients were randomized to arms with (+N) and without (-N) 1% nonoxynol-9, respectively. Patients applied the gel to affected areas every 8 hr and were evaluated biweekly. Including those crossed over, 14 patients were treated with -N. Six of fourteen (43%) achieved complete responses: biopsy proven with at least 1 year follow-up (CR). One patient achieved a partial response with at least a 50% reduction in the total surface area of all lesions present (PR). Similarly, 13 patients were treated with +N. Two patients in this group were found to have invasive cancer and one to have HIV and thus were eliminated from statistical analysis. Of the remaining 10 patients, 3 had CRs (30%), 5 had PRs (50%), and 2 failed to respond. There was no significant difference in responses between the two groups. Overall, 14 of 18 (67%) patients demonstrated some response to alpha-IFN applied topically. These data support the conclusion that alpha-IFN is an active agent in the treatment of vulvar intraepithelial neoplasia III.

Administration, Topical↗
PubMed1990

Delivery of a normal infant following cisplatin, vinblastine, and bleomycin (PVB) chemotherapy for malignant teratoma of the ovary during pregnancy.

Pregnancy complicated by an immature teratoma is rare, with a reported incidence of 0.07%. A case report of a grade 3 immature teratoma measuring 18 x 20 cm, with operative intraabdominal rupture (FIGO stage IC), is reported. The poor prognosis of malignant germ cell tumors treated by surgery alone seems to indicate a need for adjunctive chemotherapy. One course of multiagent chemotherapy consisting of cisplatin, vinblastine, and bleomycin (PVB) was initiated during the midtrimester. After an uncomplicated vaginal delivery at term of a normal infant, the planned regimen of chemotherapy was resumed. Subsequent "second-look" laparotomy was negative for malignant disease. The actual risk of PVB chemotherapy in pregnancy cannot be assessed by a single case report. The delivery of a normal infant is encouraging.

Adult↗
PubMed1990

Study of the selective cytotoxic properties of cationic, lipophilic mitochondrial-specific compounds in gynecologic malignancies.

Cationic lipophilic compounds have a unique cytotoxic mechanism of action which is dependent on mitochondrial-specific localization of these fluorescent dyes. We have demonstrated in vitro that carcinoma cells, which have a higher negative mitochondrial membrane potential than normal cells, have an increased accumulation and retention of two of these compounds. The compounds tested were rhodamine 123 and dequalinium (DECA). After the development of a reproducible murine intraperitoneal (ip) human ovarian cancer model, which maintained the biologic characteristics of the parent cell line, we undertook in vivo evaluation of DECA. Mice with intraperitoneal tumor inoculations were treated with cisplatin, and/or DECA. When compared to cisplatin, a chemotherapeutic agent known to be effective in the treatment of clinical ovarian cancer, DECA was significantly more efficacious and seemed less toxic in the murine model. Cisplatin and DECA used together were possibly synergistic. Cationic lipophilic compounds may prove to be an exciting new class of antineoplastic agents which exploit intracellular, mitochondrial differences between normal cells and cancer cells.

Animals↗
PubMed1990

Women with preeclampsia have higher plasma endothelin levels than women with normal pregnancies.

Endothelin, a newly discovered endothelium-derived peptide, has potent vasoactive properties in vivo and in vitro. The actions of endothelin in clinical conditions of hypertension have not yet been defined. This study examined the possible role of endothelin in the vasospasm and hypertension associated with a well-defined syndrome of gestational hypertension, preeclampsia. Our results indicate that the concentration of immunoreactive endothelin is elevated significantly in plasma obtained from women with preeclampsia and rapidly returns to a normal pregnancy value within 48 hours of delivery, as predicted by the prompt clinical resolution of this disorder. The findings suggest that endothelin may contribute to the vasospasm associated with this syndrome and lend further support to the involvement of endothelial cells in the pathophysiology of preeclampsia.

Adult↗
PubMed1989

Effects of anti-lipid A human monoclonal antibody on lipopolysaccharide-induced toxicity to the kidney.

Studies were done to evaluate the effects of the human monoclonal anti-lipid A IgM antibody A6(H4C5) on several components of the hemodynamic and renal toxicity of the cell wall lipopolysaccharide of E. coli 0111:B4. Antibody (0.25 to four mg./kg. BW) was administered 0.5 hour before, or premixed for one hour with, lipopolysaccharide (0.05 mg./kg., a 14 to 18% lethal dose), and the following measurements made over 0.5 to 3.5 hours of study: systemic arterial blood pressure, renal plasma flow, and glomerular filtration. The proximal tubular cell cytotoxicity of 90 mg./kg. of the cephalosporin cephaloridine was also quantified in similarly treated animals sacrificed 48 hours later. While one mg./kg. of antibody prevented the reduction by the lipopolysaccharide of renal plasma flow, it did not prevent the nephrotoxic synergy with cephaloridine, and four times the antibody dose did not prevent lipopolysaccharide-induced hypotension or reduced glomerular filtration. These amounts of this antibody protect leukopenic rabbits against the lethality of the slow onset bacteremic model of Pseudomonas conjunctivitis. It is suggested that the incompleteness of protection in this study may be the result of the sensitivity of the assay methods used and/or the acute endotoxemia produced in these animals.

Animals↗