[Comparative study on the effect of microscopic revascularization and apexification in the treatment of pulp necrosis of permanent teeth]

PURPOSE

To compare the curative effect of microscopic revascularization and apexification in the treatment of pulp necrosis of permanent teeth.

METHODS

Seventy-five cases of pulp necrosis in young permanent teeth were divided into two groups according to different treatment methods. Group A (n=30) underwent revascularization under microscope, while group B (n=45) underwent apexification. The treatment effect and pain improvement of the two groups were compared. The changes of the wall thickness and root canal length of the affected teeth before and after treatment were observed, and the bone-like deposition rate after treatment was recorded. SPSS 23.0 software package was used for statistical analysis.

RESULTS

There was no significant difference in the length of root canal between the two groups before treatment (P＞0.05); there was no significant difference in the length of root canal in group B before and after treatment (P＞0.05); the length of root canal in group A was significantly longer than that in group B 6 months after treatment(P＜0.05). There was no significant change in the thickness of root canal wall in group B before and after treatment (P＞0.05). The thickness of root canal in group A was significantly higher than that in group A 6 months after treatment (P＜0.05). Bone-like deposition rate of group A was significantly higher than that of group B 1 month and 6 months after treatment (P＜0.05). The total effective rate of group A and B was 90.00% and 84.44%, the difference was not statistically significant (P＞0.05). The cure rate of group A was 70.00%, which was significantly higher than that of group B (48.89%, P＜0.05).

COCLUSIONS

Microscopic revascularization for pulp necrosis of young permanent teeth can effectively promote root development, lengthen root canal and increase the thickness of canal wall, which is better than apexification.

[Effect of human decidua mesenchymal stem cells-derived exosomes on the function of high glucose-induced senescent human dermal fibroblasts and its possible mechanism]

Objective: To establish a high glucose senescent model of human dermal fibroblasts (HDFs), and to investigate the effects of exosomes derived from human decidua mesenchymal stem cells (dMSCs) on the proliferation, migration, and apoptosis of senescent HDFs and possible mechanism. Methods: The experimental research method was used. From January to March 2021, discarded foreskin tissue was collected for isolation and culture of primary HDFs from 4 male phimosis patients (aged 18-22 years) admitted for circumcision in the Fourth Medical Center of the PLA General Hospital. The 6th passage of HDFs were taken and divided into low glucose group and high glucose group according to the random number table, and subsequently cultured in low-glucose complete medium and high-glucose complete medium, respectively, with medium changed every 72 h without subculturing. After 10 days of culture, the cells were taken and measured for cellular senescence using the β-galactosidase kit at 24 h after seeding; the expression of senescence-related proteins p16 and p53 was assessed by Western blotting at 48 h after seeding; cell proliferation was detected at 24, 48, and 72 h after seeding using the cell counting kit 8 (CCK-8) method; the cell proliferation was evaluated by 5-ethynyl-2'-deoxyuridine (EdU) staining method, cell cycle and apoptosis were measured by flow cytometry after 48 h of seeding; Transwell experiment was used for the calculation of cell migration rate at 24 h after seeding. The human dMSCs were taken and cultured for 48-72 h from which the exosomes were extracted by differential high speed centrifugal method. The morphology of dMSC exosomes was observed by transmission electron microscopy, the particle size distribution of dMSC exosomes was measured by nanoparticle tracking analysis, and the expression of dMSC-exosomes marker proteins CD9 and tumor susceptibility gene101 (TSG101) were detected by Western blotting. The dMSC exosomes and high-glucose complete medium-induced senescent HDFs were co-cultured for 24 hours, then PKH67 kit was used to detect the uptake of exosomes by HDFs. High-glucose complete medium-induced senescent HDFs were taken and divided into high glucose alone group, high glucose+low concentration of exosomes group, and high glucose+high concentration of exosomes group according to the same method above. The high-glucose complete medium with equal volume of phosphate buffered saline, dMSC exosomes with final concentration of 50 μg/mL, and dMSC exosomes with final concentration of 100 μg/mL were added to the corresponding groups for conventional cell culture, respectively. After grouped, the cell proliferation, cell cycle and apoptosis as well as cell migration were detected by CCK-8 method and EdU staining method, flow cytometry, and Transwell experiment at the corresponding time points as before, respectively. Based on the previous results, high-glucose complete medium-induced senescent HDFs were taken and divided into high glucose alone group and high glucose+high concentration of exosomes group for the same treatment. After being grouped and cultured for 48 h, real-time fluorescent quantitative polymerase chain reaction was used to evaluate the mRNA expression of senescent-related microRNA (miR)-145-5p, miR-498, miR-503-5p, calcium/calmodulin dependent protein kinase 1D (CAMK1D), phosphates and tensin homologue deleted on chromosome ten (PTEN) gene, and Cyclin D1 in high glucose alone group and high glucose+high concentration of exosomes group. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, least significant difference t test, and independent sample t test. Results: At 24 h after seeding, the rate of β-galactosidase-positive staining of HDF in high glucose group was (38.4±4.2)%, which was significantly higher than (16.5±2.2)% of low glucose group (t=4.65, P<0.01). At 48 h after seeding, the expression levels of senescence-related proteins p16 and p53 both were significantly higher in HDFs of high glucose group than those in low glucose group (with t values of 11.85 and 3.02, respectively, P<0.05 or P<0.01). At 0, 24, 48, and 72 h after seeding, the cell proliferation viability of HDFs in high glucose group was all significantly lower than in low glucose group (with t values of 4.13, 9.90, and 15.12, respectively, P<0.01). At 48 h after seeding, the rate of EdU-positive staining of HDFs in high glucose group was obviously lower than that of low glucose group (t=3.83, P<0.05). At 48 h after seeding, the percentage of G2/M+S subpopulations in three subpopulations (G0/G1, S, and G2/M) of HDF cycle was significantly lower in high glucose group than that in low glucose group (t=8.74, P<0.01). At 24 h after seeding, the number of HDFs migrated through the filter membrane to the lower chamber was 37±6 in high glucose group, which was significantly less than 74±7 in low glucose group (t=8.42, P<0.01). At 48 h after seeding, the HDF apoptosis rate was significantly higher in high glucose group than in low glucose group (t=8.48, P<0.01). The dMSC exosomes were cup-shaped or round vesicles with well-defined edges and uniform size distribution. The size of dMSC exosomes was basically in the range of 80-200 nm. Exosomal markers including CD9 and TSG101 were positively presented on the dMSC exosomes. After being co-cultured for 24 hours, the dMSC exosomes were taken up intracellularly by HDFs and mainly distributed around the nucleus of HDFs. After being grouped and cultured for 24, 48, and 72 h, the HDF proliferation viabilities in high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group were both significantly higher than in high glucose alone group (with t values of 6.36, 6.10, 7.76, 8.92, 12.17, and 10.74, respectively, P<0.01), the HDF proliferation viability in high glucose+high concentration of exosomes group was significantly higher than in high glucose+low concentration of exosomes group (with t values of 7.92, 4.82, and 4.72, respectively, P<0.01). After being grouped and cultured for 48 h, the percentages of EdU-positive HDFs in high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group were both significantly higher than in high glucose alone group (with t values of 5.32 and 9.88, respectively, P<0.01), the percentage of EdU-positive HDFs in high glucose+high concentration of exosomes group was notably higher than in high glucose+low concentration of exosomes group (t=5.27, P<0.01). After being grouped and cultured for 48 h, the proportion of G0/G1 subpopulation in both high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group was distinctly lower (with t values of 3.81 and 4.31, respectively, P<0.05), while the proportion of G2/M+S subpopulation was markedly higher (with t values of 3.81, 4.31, respectively, P<0.05) than in high glucose alone group. After being grouped and cultured for 24 h, the number of HDFs migrated through the filter membrane in both high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group was significantly higher than in high glucose alone group (with t values of 10.14 and 13.39, respectively, P<0.01), the number of HDFs migrated through the filter membrane in high glucose+high concentration of exosomes group was significantly increased than in high glucose+low concentration of exosomes group (t=6.27, P<0.01). After being grouped and cultured for 48 h, the HDF apoptosis rates in high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group were both significantly lower than in high glucose alone group (with t values of 3.72 and 5.53, respectively, P<0.05 or P<0.01). After being grouped and cultured for 48 h, compared with those in high glucose alone group, the mRNA expression levels of miR-145-5p and miR-498 were both obviously higher (with t values of 13.03 and 8.90, respectively, P<0.01), while the mRNA expression level of miR-503-5p was significantly lower (t=3.85, P<0.05) in high glucose+high concentration of exosomes group. After being grouped and cultured for 48 h, compared with those in high glucose alone group, the mRNA expression levels of CAMK1D and PTEN gene were both significantly lower (with t values of 8.83 and 5.97, respectively, P<0.01), while the mRNA expression level of Cyclin D1 was significantly higher in high glucose+high concentration of exosomes group (t=4.03, P<0.05). Conclusions: The dMSC exosomes are capable of improving cell proliferation and migration, and inhibiting cell apoptosis of high-glucose senescent HDFs. This may be related to the mechanism by which the increased expressions of intracellular miR-145-5p and miR-498 inhibit the expression of CAMK1D and PTEN gene, and the decreased expression of miR-503-5p promote the expression of Cyclin D1.

[Vigilance against a highly lethal insecticide chlorfenapyr poisoning (report of 4 cases and literature review)]

In order to improve the clinical attention to the poisoning of chlorfenapyr, the diagnosis and treatment strategy of chlorfenapyr poisoning were discussed. This paper collected 4 cases of chlorfenapyr in the emergency department of the Second Hospital of Hebei Medical University and 4 cases of literature review, summarized the clinical characteristics of pesticide poisoning cases containing chlorfenapyr in China, and summarized and analyzed the clinical data of the cases. Seven of the 8 patients died from poisoning by chlorfenapyr. Exposure to chlorfenapyr through respiratory tract and digestive tract showed high mortality. Fever, hyperhidrosis, elevated muscle enzymes and progressive central nerve damage were its prominent clinical characteristics. Most of the initial symptoms of exposure were not serious. Some patients, especially those with low exposure dose, had a relatively stable stage with or without clinical diagnosis and treatment. In case of sweating, obvious fever and disturbance of consciousness, the condition would deteriorate rapidly, respiratory and circulatory failure and eventually die. With the increase of production capacity and market launch, people have more opportunities to be exposed to chlorfenapyr. It is urgent to strengthen the basic and clinical research of chlorfenapyr poisoning; Attention should be paid to the observation and treatment in the initial stable stage of poisoning, which can be used as a reference for the treatment of oxidative phosphoric acid dissolving coupling agent (sodium pentachlorophenol) poisoning.

Development of an imaging-planning program for screen/film and computed radiography mammography for breasts with short chest wall to nipple distance

OBJECTIVE

Imaging breasts with a short chest wall to nipple distance (CWND) using a traditional mammographic X-ray unit is a technical challenge for mammographers. The purpose of this study is the development of an imaging-planning program to assist in determination of imaging parameters of screen/film (SF) and computed radiography (CR) mammography for short CWND breasts.

METHODS

A traditional mammographic X-ray unit (Mammomat 3000, Siemens, Munich, Germany) was employed. The imaging-planning program was developed by combining the compressed breast thickness correction, the equivalent polymethylmethacrylate thickness assessment for breasts and the tube loading (mAs) measurement. Both phantom exposures and a total of 597 exposures were used for examining the imaging-planning program.

RESULTS

Results of the phantom study show that the tube loading rapidly decreased with the CWND when the automatic exposure control (AEC) detector was not fully covered by the phantom. For patient exposures with the AEC fully covered by breast tissue, the average fractional tube loadings, defined as the ratio of the predicted mAs using the imaging-planning program and mAs of the mammogram, were 1.10 and 1.07 for SF and CR mammograms, respectively. The predicted mAs values were comparable to the mAs values, as determined by the AEC.

CONCLUSION

By applying the imaging-planning program in clinical practice, the experiential dependence of the mammographer for determination of the imaging parameters for short CWND breasts is minimised.

Development and characterization of a highly specific and sensitive sandwich ELISA for detection of aggrecanase-generated aggrecan fragments

OBJECTIVE

To develop an enzyme linked immunosorbent assay (ELISA) to quantify the levels of specific aggrecan fragments generated by aggrecanase-mediated cleavage at the 373Glu-374 Ala bond within the aggrecan interglobular domain.

METHODS

The ELISA employs a commercially available monoclonal antibody to capture aggrecan fragments containing keratan sulfate (KS). Aggrecan fragments generated by cleavage at the Glu-Ala bond were then detected using a monoclonal neoepitope antibody (mAb OA-1) that specifically recognizes the N-terminal sequence 'ARGSVIL'.

RESULTS

The mAb OA-1 antibody was highly specific for the immunizing neoepitope peptide since neither peptides spanning the cleavage site nor mutated peptides were detected. Aggrecan fragments generated by ADAMTS-4 digested human aggrecan monomers and from IL-1-stimulated human cartilage explants were quantified by the ELISA, and we observed increased sensitivity of the ELISA compared to mAb OA-1 Western analysis. We also observed that the basal, as well as IL-1-stimulated production of ARGS aggrecan fragments from human articular cartilage explants was blocked by a selective aggrecanase inhibitor, consistent with generation of the ARGS neoepitope in human articular cartilage being mediated by aggrecanase. Using purified human aggrecan digested by ADAMTS-4 as standard to quantify ARGS aggrecan fragments in human synovial fluids, we determined that the calculated amount of ARGSVIL-aggrecan fragments by ELISA measurement is in agreement with the published levels of these fragments, supporting its potential utility as a biomarker assay for osteoarthritis.

CONCLUSION

We have developed an assay that detects and quantifies specific aggrecan fragments generated by aggrecanase-mediated cleavage. Because aggrecanase mediates degradation of human articular aggrecan in joint disease, the KS/mAb OA-1 ELISA may serve as a biomarker assay for evaluation of preclinical and clinical samples.

The anti-apoptotic role of interleukin-6 in human cervical cancer is mediated by up-regulation of Mcl-1 through a PI 3-K/Akt pathway

Interleukin-6 (IL-6), a multifunctional cytokine, has recently been implicated in human cervical cancer, though the mechanism remains elusive. This study demonstrates that the anti-apoptotic protein Mcl-1 and IL-6 was concomitantly expressed in human cervical cancer tissues and cell lines, but not in normal cervix tissues. Upon IL-6 treatment, Mcl-1, but not other Bcl-2 family members, was rapidly up-regulated peaking at 4-8 h in human cervical cancer C33A cells. Supporting this observation, using anti-IL-6 or anti-IL-6 receptor antibody to interrupt the IL-6 autocrine loop in SiHa cells significantly reduced cellular level of Mcl-1. This study hypothesizes that the expression of Mcl-1 in cervical cancer cells is regulated by IL-6. The matter of which signaling pathways transduced by IL-6 is responsible for the Mcl-1 up-regulation is further investigated herein. Blocking the STAT3 or MAPK pathway with dominant-negative mutant STAT3F or the MEK inhibitor PD98059 failed to inhibit IL-6-mediated Mcl-1 expression. Meanwhile, the IL-6-induced Mcl-1 up-regulation was effectively abolished by treatment with PI 3-K inhibitors, LY294002. Additionally, overexpression of dominant-negative (dn) Akt in C33A cells could inhibit the IL-6-induced increase of Mcl-1. Finally, overexpression of IL-6 in C33A cells caused a markable resistance to apoptosis induced by doxorubicin or cisplatin. Transient transfection of IL-6-overexpressed cells with a mcl-1 antisense vector, leading to the attenuation of their apoptosis-resistant activity. In conclusion, the data herein suggest that IL-6 regulated the mcl-1 expression via a PI 3-K/Akt-dependent pathway that may facilitate the oncogenesis of human cervical cancer by modulating the apoptosis threshold.

Detection of superficial zone protein in human and animal body fluids by cross-species monoclonal antibodies specific to superficial zone protein

In this report we describe the purification of human superficial zone protein (SZP), the generation of cross-species monoclonal antibodies (MAbs) and the detection of this protein in human and animal body fluids. Human SZPs, used as immunizing antigens, were purified either from culture media of human cartilage organ cultures or from human synovial fluids. The immunizing antigens were mixed with RIBI adjuvant in one of three forms: nonmodified SZP, superficial zone protein-keyhole limpet hemocyanin conjugate (SZP-KLH), or a mixture of superficial zone protein and hyaluronic acid (SZP-HA). A panel of MAbs including GW4.23, S6.79, S13.52, S13.233, and S17.109 were generated and characterized. Monoclonal antibody (MAb) S6.79, an IgG2b with K(D) 3.14 x 10(-9) M from SZP-KLH immunization, is of particular interest. It reacts strongly to a large molecular weight form of SZP in both enzyme-linked immunosorbent assay (ELISA) and Western blotting. It stains the most superficial layer of articular cartilage in immunohistochemistry, whereas the middle and deep zones of cartilage are not stained. When MAb S6.79 was applied to Western blots of human body fluids, a strong 345-kDa band was detected in samples of synovial fluid and weaker bands of similar size were detected in samples of plasma and serum. MAb S6.79 also showed cross-species immunoreactivity with SZP in samples of synovial fluids harvested from bovine, dog, guinea pig, and rabbit, as demonstrated by Western blotting and antibody absorption experiments. This cross-species MAb will be a useful tool in human and animal model studies for monitoring SZP levels and tissue distribution. It may help define the roles of SZP in normal articular joints and may be of diagnostic or prognostic value for the measurement of SZP in pathological conditions such as osteoarthritis, rheumatoid arthritis, and camptodactyly-arthropathy-coxa vara-pericarditis.

Progression of symptoms in the early and middle stages of Huntington disease

OBJECTIVE

To delineate the progression of symptoms in the early and middle stages of Huntington disease (HD).

DESIGN

A survey of individuals with symptomatic HD completed by a first-degree relative.

SETTING

The National Huntington Disease Research Roster for Patients and Families, Indianapolis, Ind.

PARTICIPANTS

The survey included 1238 individuals with a minimum of a 6-year history of symptomatic HD.

MEASURES

Participating families completed a series of surveys, including the Affected Individual Questionnaire, which consists of 19 physical, emotional, and cognitive signs commonly thought to occur during disease progression. The respondent indicates if each of the symptoms occurred and, if so, at what time during the course of the disease: (1) within 1 year, (2) within 2 to 5 years, (3) within 6 to 10 years, (4) after more than 10 years, (5) has not occurred, or (6) "don't know."

RESULTS

The symptoms are categorized into 6 onset periods. Involuntary movements are grouped alone as the earliest reported symptom. The second group is composed entirely of mental and emotional symptoms, including sadness, depression, and difficult to get along with. The third group includes clumsiness, sexual problems, lack of motivation, and suspiciousness/paranoia. As the disease progresses, a variety of motor, emotional/behavioral, and cognitive symptoms are experienced, including unsteadiness, trouble holding onto things, trouble walking, changes in sleeping patterns, delusions and hallucinations, intellectual decline, and memory loss. With the approach of late-stage HD, affected individuals begin to experience speech difficulty and weight loss. In the late stage, patients lose bowel and bladder control.

CONCLUSIONS

Even though the symptoms of HD are fairly well characterized, their progression, especially in the early and middle stages, remains uncertain. Clarification of the disease progression is vital to improved understanding of the pathogenesis of HD and to the evaluation of therapeutic agents that are designed to slow the progression of disease. The results of this study assist in clarifying HD progression from early involuntary movements and emotional changes to more overt motor symptoms and difficulty with activities of daily living.

Production and characterization of an estrogen receptor beta subtype-specific mouse monoclonal antibody

An important step in differentiating the unique physiological roles of the alpha and beta forms of estrogen receptor is to determine the precise expression pattern of each of these receptors. We report the generation and characterization of a murine IgG1 monoclonal antibody (MAb), ER15.64A that is ERbeta subtype-specific and capable of recognizing full-length human ERbeta as well as all of its known protein isoforms. ER15.64A, raised against a ERbeta peptide (aa2-18)-keyhole limpet hemocyanine conjugate, reacted to the immunizing peptide and the full-length E. coli expressed ERbeta in ELISA and BIAcore assays. It also immunostained nuclei of Sf9 insect cells that were infected with an ERbeta-baculovirus. In Western analysis, ER15.64A recognized ERbeta1 and ERbeta2 proteins from a reticulocyte in vitro transcription/translation preparation. This antibody did not cross-react with recombinant ERalpha in ELISA, BIAcore, immunocytochemistry, or Western blot analysis. The specificity of ER15.64A should make this antibody a useful tool for monitoring expression of ERbeta and its isoforms at the protein level and should aid in distinguishing the pattern of ERbeta receptor expression from that of ERalpha.

Vascular endothelial cell growth factors promote the in vitro development of rat photoreceptor cells

We have identified and characterized a novel trophic effect of vascular endothelial cell growth factor (VEGF) on photoreceptor cells. Treatment of retinal cultures, derived from postnatal day 1 (P1) rats, with VEGF-2 resulted in a dose- and time-dependent increase in the level of rhodopsin protein, as determined by ELISA assay. After 7-9 d of treatment the VEGF-1 or VEGF-2, at a concentration of 10 ng/ml, induced a 200-300% increase in rhodopsin protein and a 220% increase in the number of rhodopsin-immunopositive cells. Treatment with VEGF-2 induced a 250% increase in the number of syntaxin-immunopositive cells and a 67% increase in high-affinity GABA uptake, both markers for amacrine cells. In contrast, there was no increase in the non-neuronal cell populations. VEGF-2 induced an approximately 300% increase in the number of bromodeoxyuridine-labeled (BrdU) retinal cells within 48 hr of treatment. After 3 d in culture both the basal and stimulated levels of BrdU incorporation were reduced, suggesting that the proliferative effect of VEGF was restricted developmentally. Furthermore, there was a developmentally dependent increase in the mitogenic response to VEGF-2, with retinal cultures derived from E15, E20, or P1 animals demonstrating a 50, 100, and 300% increase in thymidine incorporation, respectively. However, VEGF treatment resulted in an increase in the number of rhodopsin-immunopositive cells only when the cultures were derived from P1 animals. Therefore, retinal progenitor cells appear to be targets for VEGF, and thus VEGF may be involved in the regulation of the early developmental program of retinal neurogenesis.

Endoscopic management of skull base osteoradionecrosis

OBJECTIVE

Osteoradionecrosis is one of the most serious complications in radiotherapy of nasopharyngeal carcinoma. We describe a new endoscopic approach to resolve resultant skull base osteoradionecrosis. The objective of this study is to evaluate the efficacy of endoscopic management of skull base osteoradionecrosis.

STUDY DESIGN

A prospective study of the outcome of endoscopic management for patients with skull base osteoradionecrosis.

METHODS

Between 1994 and 1998 six patients who had irradiation previously for nasopharyngeal carcinoma had skull base osteoradionecrosis. A sinoscopic approach was applied for diagnosis and sequestrectomy. This diagnosis was based on the criterion of exposed necrotic bone after removing all crust in the nasopharynx and further confirmed on pathological examination after sequestrectomy. Effective cure was defined as intact mucosal coverage without any ulcer or exposed necrotic bone observed in the nasopharynx and the absence of antecedent accompanying symptoms after management.

RESULTS

Six patients (10%) were symptom free. Five (83.3%) patients had effective cure. There was no surgical morbidity or mortality.

CONCLUSION

Endoscopic sequestrectomy is a justified approach to skull base osteoradionecrosis.

Suramin analogs inhibit human angiogenesis in vitro

BACKGROUND

Suramin is a polysulfonated naphthylurea that inhibits tumor cell proliferation and angiogenesis, but the widespread use of this drug has been limited by significant neurologic toxicity. A series of suramin analogs that may exhibit less toxicity in vivo have been synthesized. We hypothesized that these novel analogs would have antiangiogenic properties equal to or greater than those of suramin when evaluated in an in vitro human placental vein angiogenesis model.

METHODS

Human placental veins (n = 72 per group) were cultured in a 0.3% fibrin clot for a period of 14 days. Three suramin analogs (NF 145, NF 248, NF 293) and suramin were tested at 56 and 560 microM concentrations to determine their effect on the development of an angiogenic response. Experiments were repeated for each analog on veins from three different placentas. The percentage of wells that initiated an angiogenic response was calculated and compared with initiation in a control group (n = 141).

RESULTS

The three suramin analogs inhibited angiogenesis in a dose-dependent fashion, with all compounds exhibiting near-complete inhibition of angiogenesis at 560 microM. The effects of these analogs were equal to or greater than those of suramin.

CONCLUSION

Suramin analogs with structural alterations inhibit human angiogenesis at concentrations equivalent to those seen in vivo. These analogs may be more effective antiangiogenic agents than suramin and may have less potential for toxicity.

Replication-associated activities of purified human papillomavirus type 11 E1 helicase

Replication of human papillomavirus type11 (HPV11) requires both the E1 and the E2 proteins. E1 is structurally and functionally similar to SV40 large T-antigen and is a DNA helicase/NTPase that binds to the origin of replication and initiates viral DNA replication. The biochemical characterization of HPV E1 is incompletely documented in the literature in part because of difficulties in expressing and purifying the protein. Herein, we report a method for the overexpression of full-length, untagged E1 (73.5 kDa) in baculovirus-infected Trichoplusia ni insect cells and the purification to homogeneity using a two-step procedure. The purified protein is a nonspecific NTPase that hydrolyzes ATP, dATP, UTP, or GTP equally well. Point mutations were made in the putative NTPase domain to verify that the activities observed were encoded by E1. Purified mutant D523N had negligible ATPase and helicase activities but retained DNA-binding activity. Sedimentation equilibrium ultracentrifugation and glycerol gradient centrifugation demonstrated that the wild-type protein is primarily a hexamer in its purified form. Secondary structure determination by circular dichroism revealed a large percentage of alpha-helical structure consistent with secondary structure predictions. These data define a fundamental set of biochemical and kinetic parameters for HPV E1 which are a critical prerequisite to future mechanistic studies of the enzyme.

Production of monoclonal antibodies using recombinant baculovirus displaying gp64-fusion proteins

Generation of protein immunogens is often a rate-limiting step in the production of monoclonal antibodies (Mabs). Expressing domains of proteins as fusions to the baculovirus surface glycoprotein gp64 displays foreign proteins on the surface of the virion. Antigen is produced by inserting a gene fragment in-frame between the signal sequence and the mature protein domain of the gp64 nucleotide sequence. This method allows immunization with whole virus, eliminating the need for purification of target antigens. Affinity-matured Mabs to the human nuclear receptors LXRbeta and FXR have been produced using baculovirus particles displaying gp64/nuclear receptor fusion proteins as the immunizing agent. Immunizations were performed directly with pelleted virus using the Repetitive Immunization Multiple Sites (RIMMS) immunization strategy for rapid Mab production. All Mabs were identified using insect cells infected with the immunizing virus. Characterization of these antibodies shows them to be class-switched and specific for LXRbeta or FXR. Additionally, high affinity antibodies that recognize gp64 and neutralize baculovirus infection of insect cells were isolated. Use of the recombinant baculovirus gp64 display system makes possible the production of Mabs once a partial DNA sequence is known. This allows the generation of antibodies prior to the isolation of purified protein, in turn providing antibodies to facilitate purification, characterization and immunolocalization of proteins.

Expression of wild-type estrogen receptor beta and variant isoforms in human breast cancer

It has been shown in previous studies that a variety of estrogen receptor (ER) beta mRNA transcripts are expressed in human breast cancer cell lines and tumors. To complement the RNA expression studies, we have developed ER-beta-specific antibodies to characterize ER-beta protein expression in breast cancer cell lines and tumors. Monoclonal antibodies were made against a peptide representing the first 18 amino acids of the longest ER-beta open reading frame reported to date, and polyclonal antibodies were made against a peptide within the ER-beta B domain. By Western blot analysis, we show that ER-beta protein is expressed in all cancer cell lines tested and in three of five breast tumor samples. The breast cancer cell lines showed variation in the size of the expressed ER-beta protein. The longest form detected was consistent with the 530-amino acid, full-length ER-beta sequence. Shorter ER-beta isoforms were detected in the ER-alpha-negative MDA-MB-231 and MDA-MB-435 breast cancer cell lines, likely corresponding to previously described COOH-terminal RNA variant isoforms.

Specific sequence elements are required for the expression of functional tumor necrosis factor-alpha-converting enzyme (TACE)

The tumor necrosis factor-alpha-converting enzyme (TACE) is a membrane-anchored zinc metalloprotease involved in precursor tumor necrosis factor-alpha secretion. We designed a series of constructs containing full-length human TACE and several truncate forms for overexpression in insect cells. Here, we demonstrate that full-length TACE is expressed in insect cells inefficiently: only minor amounts of this enzyme are converted from an inactive precursor to the mature, functional form. Removal of the cytoplasmic and transmembrane domains resulted in the efficient secretion of mature, active TACE. Further removal of the cysteine-rich domain located between the catalytic and transmembrane domains resulted in the secretion of mature catalytic domain in association with the precursor (pro) domain. This complex was inactive and function was only restored after dissociation of the complex by dilution or treatment with 4-aminophenylmercuric acetate. Therefore, the pro domain of TACE is an inhibitor of the catalytic domain, and the cysteine-rich domain appears to play a role in the release of the pro domain. Insect cells failed to secrete a deletion mutant encoding the catalytic domain but lacking the inhibitory pro domain. This truncate was inactive and extensively degraded intracellularly, suggesting that the pro domain is required for the secretion of functional TACE.

Systematic management of osteoradionecrosis in the head and neck

OBJECTIVES

Osteoradionecrosis is one of the most serious and devastating complications of radiotherapy. The proper management of osteoradionecrosis is currently undetermined. The objective of this study is to evaluate the treatment results of a systematic approach to osteoradionecrosis.

STUDY DESIGN

A prospective study of a systematic approach to osteoradionecrosis in the head and neck area was undertaken.

METHODS

From July 1993 to June 1998, 33 cases of osteoradionecrosis in the head and neck area were treated using a systematic approach that combined sequestrectomy and hyperbaric oxygen therapy.

RESULTS

Seven (21%) had recurrent cancer. The control rate of the other 26 osteoradionecrosis cases was 77% (20/26).

CONCLUSIONS

Persistent osteoradionecrosis, despite diligent radical treatment, raises the suspicion of recurrent cancer. Extensive osteoradionecrosis with a multiple discharging fistula, a large area of exposed necrotic bone, or a coexistent fracture should be treated primarily with radical sequestrectomy and microvascular free flap reconstruction. Surgery still plays a major role in controlling osteoradionecrosis, and hyperbaric oxygen therapy is adjuvant.

Computer system for four-dimensional transesophageal echocardiographic image reconstruction

This paper presents a system for reconstructing a four-dimensional (4D) heart-beating image from transesophageal echocardiographic (TEE) data acquired with a rotational approach. The system consists of the necessary processing modules for two-dimensional (2D) echocardiogram reformation and 3D/4D-image reconstruction. These include the modules of image decoding, image re-coordinating, and three-dimensional (3D) volume rendering. The system is implemented under PC platform with Windows 95 operating system (with Intel Pentium-166 CPU, 64 MB RAM on board, and 2.0 GB hard disk capacity). It takes 6 min to reconstruct a 4D echocardiographic data set. The resultant 2D/3D/4D echocardiographic image provide the tools for investigating the phenomenon of heart beating, exploring the heart structure, and reformatting the 2D echocardiograms in an arbitrary plane. The functions provided by the system can be applied for further studies, such as 3D cardiac shape analysis, cardiac function measurement, and so forth.

Use of a PPAR gamma-specific monoclonal antibody to demonstrate thiazolidinediones induce PPAR gamma receptor expression in vitro

Troglitazone and rosiglitazone (BRL49653), members of the thiazolidinedione (TZD) class of antidiabetic drugs, are peroxisome proliferator-activated receptor gamma (PPARgamma) ligands that induce adipocyte differentiation and increase the expression of PPARgamma protein. Here, we report the characterization of a PPARgamma specific monoclonal antibody (MAb), PgammaA53.25, and its use to monitor PPARgamma expression in the noncommitted pluripotent murine mesenchymal stem cell line, C3H10T1/2, treated with TZDs. MAb PgammaA53.25 was raised against a region in the N-terminal domain of human PPARgamma shared by splice variants PPARgamma1 and PPARgamma2. It recognizes immunizing antigen in enzyme-linked immunoadsorbent assay (ELISA), and does not cross-react with the N-terminal domains of PPARalpha or PPARdelta. In Western blotting, PgammaA53.25 reacts with the immunizing antigen as well as distinct protein bands corresponding to the molecular weight of full length PPARgamma from C3H10T1/2 cells and rat tissue lysates. In fluorescent microscopy, PgammaA53.25 immunostains nuclei of C3H10T1/2 cells treated with PPARgamma ligands. The fluorescence intensity of the treated cells is TZD dose-dependent, and correlates with lipid accumulation consistent with adipogenesis. Based on these results, we propose that MAb PgammaA53.25 will be a useful tool for elucidating the role of PPARgamma in fatty acid metabolism and adipocyte differentiation.

Assessment of left ventricular cardiac shape by the use of volumetric curvature analysis from 3D echocardiography

A method for three-dimensional shape analysis of left ventricle (LV) is presented in this article. The method uses three-dimensional transesophageal echocardiography (TEE) as the source to derive the 3D wire-frame model and the related shape descriptors. The shape descriptors developed in this article include regional surface changing (RSC), global surface curvature (GSC), surface distance (SD), normalized surface distance (ND), and effective radius (ER) of the endocardial surface. Based on these shape descriptors, the shape of LV could be sketched in both static and dynamic manner. The results show that the new approach provides a robust but easy method to quantify regional and global LV shape from 2D and 3D echocardiograms.

[Effects of myocardial ischemia reperfusion injury on L-arginine/nitric oxide system in rat heart]

Ischemia reperfusion injury (IRI) model of rat heart was prepared by preperfusion for 15 min, then a suspension for 45 min and recycling reperfusion for 15 min with 30 ml KH buffer. The leakage of lactate dehydrogenase(LDH),protein, myoglobin and nitrite (NO2-) in the circular perfusion fluid were measured. Myocardial nitric oxide synthase(NOS) activity and L-arginine transport were observed. In the IR group, the leakage of LDH,protein, myoglobin and NO2- were increased respectively by 4.1,5.4,1 and 1.2 times(P<0.01) and NOS(tNOS, iNOS, cNOS) activity by 48.2%,43.2% and 52.1%,(P<0.01,respectively) as compared with the control group. L-arginine transport might be mediated by either high- or low-affinity transport system in cardiac tissue. In the IR group, L-arginine transport increased significantly with the V(max) being increased by 48% and 2 times respectively for the low-affinity and the high-affinity transport as compared with control. Michaelis constant (km) was decreased by 47.4% for low-affinity transport (P<0.05),but not significantly changed for the high-affinity transport. These results suggest that the increase of nitric oxide generation might result from the increased myocardial NOS activity and L-arginine transport during IRI.

A unified multimedia database system to support telemedicine

A unified approach to managing multimedia medical databases in a telemedicine system is proposed. In order to manage, search, and display patient information more efficiently, we define a patient information package (PIP) as a concise data set of a patient's medical information from each visit. By means of PIP's, both patient-oriented and problem-oriented query strategies, which are most frequently used in daily clinical practice and medical education, can be accommodated. We also provide a unified methodology for accessing various types of patient medical records as well as design two types of user interfaces, high-quality data display and web-based interface, for different medical service purposes. The PIP-based management of databases has been successfully implemented between the National Taiwan University (NTUH), Taipei, and the Chinshan health care center, Chinshan, Taiwan, for teleconsultation, telediagnosis, and tele-education.

Cloning and characterization of human estrogen receptor beta isoforms

Multiple transcripts which arise from the human estrogen receptor beta (ER beta) gene have been characterized. Three full length isoforms of the hER beta gene, designated hER beta 1-3, were identified in a testis cDNA library. An additional two isoforms, designated hER beta 4 and hER beta 5, were identified by PCR amplification from testis cDNA and from the MDA-MB 435 cell line. hER beta 1 corresponds to the previously described hER beta. All five isoforms diverge at a common position within the predicted helix 10 of the ligand binding domain of hER beta, with nucleotide sequences consistent with differential exon usage. The hER beta isoform mRNAs displayed a differential pattern of expression in human tissues and in tumor cell lines when analyzed by RT-PCR. Further characterization of the three full length isoforms, hER beta 1-3, by in vitro band shift studies indicated that the isoforms were able to form DNA-binding homodimers and heterodimers with each other and with the ER alpha subtype.

Monitoring of PPAR alpha protein expression in human tissue by the use of PPAR alpha-specific MAbs

We report the production and characterization of two PPAR alpha subtype-specific monoclonal antibodies raised against the N-terminal domain of PPAR alpha. P alpha b 11.80A is a Western-reactive antibody, whereas P alpha b 32.51 is useful for immunohistochemistry. Both antibodies exhibited high affinity against the immunogen based on BIAcore analysis, recognized full-length PPAR alpha protein in PPAR alpha-transfected CV-1 cells, and displayed no cross-reactivity against the N-terminal domains of PPAR gamma or PPAR delta proteins as demonstrated by various immunoassays. The application of these antibodies to a panel of normal human tissues revealed that PPAR alpha protein expression is highest in skeletal muscle, liver, and kidney, consistent with previously reported mRNA expression data. These antibodies provide us with valuable tools to further explore the function of PPAR alpha.

Neutralizing IGF-1 monoclonal antibody with cross-species reactivity

We report the generation of a murine IGF-1 monoclonal antibody designated 35I17, which exhibits unique cross-species reactivity. The antibody recognizes recombinant human and rat IGF-1 in ELISA, Western blots, and in an 125I-recombinant human IGF-1 Scintillation Proximity Assay. In addition, 35I17 blocks cell proliferation induced by recombinant human and rat IGF-1, and inhibits cell proliferation induced by sera from human, rat, calf, dog, goat, or mouse. The antibody inhibits rat IGF-1 binding to IGF-1 receptors, and prevents IGF-1-stimulated receptor and IRS-1 phosphorylation in LISN C4 cells, an IGF-1 receptor-transfected cell line. The cross-species and neutralizing properties of 35I17 may be useful in in vitro and in vivo animal studies for elucidating the role of IGF-1 in cancer, rheumatoid arthritis, and other diseases.

Rapid development of affinity matured monoclonal antibodies using RIMMS

Affinity matured murine monoclonal antibody producing cell lines can now be rapidly generated using a novel repetitive, multiple site immunization strategy designated RIMMS. RIMMS capitalizes on rapid hypermutation and affinity maturation events which occur in B cell populations localized within secondary lymphatic tissue early in response to antigenic challenges. A murine myeloma cell line, P3XBcl-2-13, stably transfected with Bcl-2, enhances the outgrowth of hybridomas following somatic fusion with immune lymphocytes isolated from pooled peripheral lymph nodes (PLN) 8-14 days after the initial immunization. Immunizations somatic fusion, screening and isolation of affinity matured IgG secreting monoclonal antibody cell lines occur within a one month time period. By using RIMMS, we have been able to expedite the isolation of affinity matured monoclonal antibodies to numerous antigens, including a drug hapten.

TNF alpha-mediated inhibition and reversal of adipocyte differentiation is accompanied by suppressed expression of PPARgamma without effects on Pref-1 expression

Tumor necrosis factor alpha (TNF alpha) is a polypeptide hormone with pleiotropic effects on cellular proliferation and differentiation. To investigate how TNF alpha inhibits and reverses adipocyte differentiation, we studied the expression of two factors involved in the adipocyte differentiation process. Peroxisome proliferator-activated receptor gamma (PPARgamma) is a positive regulator of adipogenesis, whereas preadipocyte factor 1 (Pref-1) inhibits adipocyte differentiation. The expression patterns of both PPARgamma and Pref-1 change during early stages of adipocyte differentiation. Decreased expression of Pref-1 and increased expression of PPARgamma occur 1 day and 2 days, respectively, after 3T3-L1 cells reach confluence. During TNF alpha-mediated inhibition of adipocyte differentiation, PPARgamma messenger RNA (mRNA) expression stays at low levels. In contrast, TNF alpha treatment has no effect on the normal decrease in Pref-1 gene expression that occurs during adipogenesis. We observed that certain cytokine and growth factors [such as TNF alpha, basic fibroblast growth factor, transforming growth factor beta, and protein kinase C-activating agents plus calcium ionophore], when added to differentiated adipocytes, cause rapid down-regulation of PPARgamma mRNA expression with concomitant decrease in adipocyte-specific gene expression but fail to increase Pref-1 mRNA expression. Moreover, addition of TNF alpha to fully differentiated adipocytes results in the rapid disappearance of PPARgamma protein expression and the rapid loss of PPARgamma DNA-binding activity. Therefore, Pref-1 seems to function as a nonreversible molecular checkpoint whose expression is insensitive to TNF alpha-generated signals, whereas PPARgamma expression remains sensitive to TNF alpha at all stages of the adipogenesis program. Our results support the notion that dedifferentiated adipocytes and preadipocytes are not identical, though they share many similar morphological and gene expression patterns.

Cloning of a disintegrin metalloproteinase that processes precursor tumour-necrosis factor-alpha

Tumour-necrosis factor-alpha (TNF-alpha) is a cytokine that contributes to a variety of inflammatory disease states. The protein exists as a membrane-bound precursor of relative molecular mass 26K which can be processed by a TNF-alpha-converting enzyme (TACE), to generate secreted 17K mature TNF-alpha. We have purified TACE and cloned its complementary DNA. TACE is a membrane-bound disintegrin metalloproteinase. Structural comparisons with other disintegrin-containing enzymes indicate that TACE is unique, with noteable sequence identity to MADM, an enzyme implicated in myelin degradation, and to KUZ, a Drosophila homologue of MADM important for neuronal development. The expression of recombinant TACE (rTACE) results in the production of functional enzyme that correctly processes precursor TNF-alpha to the mature form. The rTACE provides a readily available source of enzyme to help in the search for new anti-inflammatory agents that target the final processing stage of TNF-alpha production.

Activation of the nuclear receptor LXR by oxysterols defines a new hormone response pathway

Accumulation of cholesterol causes both repression of genes controlling cholesterol biosynthesis and cellular uptake and induction of cholesterol 7alpha-hydroxylase, which leads to the removal of cholesterol by increased metabolism to bile acids. Here, we report that LXRalpha and LXRbeta, two orphan members of the nuclear receptor superfamily, are activated by 24(S), 25-epoxycholesterol and 24(S)-hydroxycholesterol at physiologic concentrations. In addition, we have identified an LXR response element in the promoter region of the rat cholesterol 7alpha-hydroxylase gene. Our data provide evidence for a new hormonal signaling pathway that activates transcription in response to oxysterols and suggest that LXRs play a critical role in the regulation of cholesterol homeostasis.

Fluorescent microtiter screening assay for immunocytochemically reactive antibodies

We have developed a rapid in situ screening procedure that enables prescreening of hundreds of hybridomas in a 96-well format. The procedure involves fluorescence immunostaining of cells cultured in 96-well plates and the use of a fluorescence plate reader to detect reactive antibodies. Positive immunostaining in individual well, as denoted by elevated readings, is then confirmed by fluorescence microscopy. Using the method described here, we have successfully identified monoclonal antibodies that are specific to the nuclear receptor, peroxisome proliferator-activated receptor gamma (PPAR gamma). This assay is readily applicable for screening hybridomas raised against cell surface or intracellular antigens to aid in the initial identification of antibodies reactive in immunocytochemical procedures.

Fitting characteristics of 1-day and 14-day Acuvue disposable contact lenses

The fitting characteristics of 1-day Acuvue disposable soft contact lenses (SCLs) [base curve (BC) 9.0 mm, diameter 14.2 mm] and 14-day Acuvue disposable SCLa (BC 8.8 mm, diameter 14.0 mm) were evaluated and compared with respect to lens centration and post-blink movement in primary gaze and in upgaze. In this double-blind study 25 successful daily wearers of either the 1-day lens or the 14-day lens with the same parameters were randomly fit with three 1-day lenses and three 14-day lenses for a total of 6 lenses per eye. The lene fit was evaluated 5 min after insertion. Lens centration was assessed by measuring temporal, nasal, superior and inferior limbal coverage, and then comparing the net horizontal centration (temporal minus nasal coverage) and the net vertical centration (superior minus inferior coverage) of the 1-day and 14-day lenses. There was no significant difference between the two lenses in terms of temporal, superior, and inferior limbal coverage (p > 0.05). However, the 1-day lens showed statistically more nasal coverage (p < 0.05). No statistically significant difference in movement or in horizontal and vertical differences in centration were found (p > 0.05). Although our findings indicate a subtle statistical difference in fitting characteristics, clinically the two lenses should provide similar fits.

Monoclonal antibodies against human collagenase and stromelysin

Mouse monoclonal antibodies against recombinant human fibroblast procollagenase and prostromelysin have been generated and characterized. The epitope-containing domains for the antibodies have been assigned based on their immunoreactivities against recombinant proenzymes, mature enzymes, truncated collagenases, proteolytic fragments of stromelysin, and chimeric molecules constructed from different domains of the two enzymes. These antibodies can be divided into four groups: (1) antibodies that recognize the truncated 19-kDa NH2-terminal collagenase, (2) antibodies that recognize the C-terminal domain of collagenase and stromelysin, (3) antibodies that recognize a 31-kDa NH2-terminal collagenase fragment, and (4) antibodies that recognize the 19-kDa NH2-fragment of stromelysin. The prostromelysin-specific antibody 11N13 is of particular interest; it neutralizes stromelysin activity in a stromelysin peptide substrate assay, with an IC50 value of 75 nM. MAb 11N13 may be useful for in vivo and in vitro studies to validate the roles of stromelysin in tumor cell invasion, metastasis, and connective tissue disorders.

Vibration arthrometry of the knee with torn meniscus: a preliminary report

Although projects using vibration signals generated by the joint to detect joint disorders are still experimental, vibration arthrometry has been shown to be useful in assessing meniscal pathology. A prospective study using vibration arthrometry to diagnose meniscal tears was carried out in 25 consecutive patients with knee injuries. They comprised 20 males and five females with an average age of 34 years. An arthroscopic examination of the injured knee was given to every patient. Six cases of medial meniscal tear, 12 lateral meniscal tear, and two torn discoid menisci were found. The remaining five cases had normal menisci. By correlating the vibration arthrography of the patients to their corresponding arthroscopic findings, 15 were found to be true-positive, five true-negative and five false-negative. There were no false-positive readings. The accuracy, sensitivity and specificity of the vibration arthrometry in diagnosing meniscal tear was 80%, 75% and 100%, respectively. Vibration arthrometry was shown to be a reliable, non-invasive diagnostic tool in diagnosing meniscal tear of the knee.

The effect of 3,3-di-pyridyl-methyl-1-phenyl-2-indolinone on the nerve terminal currents of mouse skeletal muscles

The effects of 3,3-dipyridyl-methyl-1-phenyl-2-indolinone (DPMPI), a new cognition enhancer, on perineural waveforms were assessed on triangularis sterni nerve-muscle preparations in the mouse. The perineural waveforms were recorded with extracellular electrodes placed in the perineural sheaths of motor nerves. At 64.5 microM, DPMPI decreased the fast potassium current of the nerve terminal. The sodium current, calcium currents and calcium-dependent potassium current of the nerve terminal were not affected. At a greater concentration (215 microM), DPMPI decreased all of the components of the waveforms associated with sodium, potassium and calcium currents. It is concluded that DPMPI affects potassium, as well as sodium currents in the nerve terminal. The effect may contribute to its pharmacological actions on synaptic transmission.

Amino acid sequence determination of ancrod, the thrombin-like alpha-fibrinogenase from the venom of Akistrodon rhodostoma

The thrombin-like serine protease and antithrombotic agent, Ancrod, was rapidly purified from the crude venom of Akistrodon rhodostoma by agmatine-Sepharose affinity chromatography followed by MonoQ anion exchange chromatography. N-Terminal sequencing and analysis of overlapping proteolytic fragments of purified Ancrod by automated Edman degradation in combination with tandem mass spectroscopy allowed the determination of the 234 amino acid sequence of the protease. Glycosylation sites at all five canonical N-linked glycosylation sites were inferred from the appearance of blank sequencer cycles in the amino acid sequence and were confirmed by mass spectroscopic analysis of the N-glycanase-treated peptides. Monoclonal antibodies raised against the denatured protein and HF-deglycosylated protein recognized Ancrod on Western blots. Sequence comparison to other thrombin-like serine proteases and reptilian fibrinogenases revealed a number of similarities, most notably the catalytic triad and many conserved cysteine positions.

Study of the activities of Chinese herb Viscum alniformosanae Part II: The components of conditioned medium produced by Viscum alniformosanae-stimulated mononuclear cells

The human promyelocytic cell line HL-60 can be induced to monocytoid terminal differentiation by several conditioned media produced by lectin-stimulated mononuclear cells. We reported previously that a 572-conditioned medium (CM) secreted from viscum alniformosanae-stimulated mononuclear cells also had the capacity of inducing HL-60 leukemic cells into mature monocytes. In the present study, we showed that 572-CM did not contain IFN-r, TNF, IL-1 and IL-2 as determined by using ELISA tests. This CM was unable to induce granulocyte-macrophage colony formation. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was used to detect the components of this CM. After running the acrylamide gels, a wide band protein, in the 65-80 kd range was obtained and it was different from those of other mitogens.

The effect of 3,3-dipyridylmethyl-1-phenyl-2-indolinone on the neuromuscular transmission in the rodent skeletal muscles

The effects of a cognition enhancer, 3,3-dipyridylmethyl-1-phenyl-2-indolinone (DPMPI) (21.5-645 microM), on neuromuscular transmission were studied electrophysiologically on diaphragms of mouse and rat and the soleus muscle of rat. The drug DPMPI (21.5-645 microM) increased both direct and indirect twitch tension of mouse diaphragm. It also increased (a) the frequency of miniature endplate potentials and (b) the quantal content of endplate potential. However, DPMPI (64.5 microM) affected neither the amplitude of the directly elicited action potential of soleus muscle in the rat nor the magnitude of the resting membrane potential of mouse diaphragm, although DPMPI (215 microM) decreased the amplitude of the compound action potential of phrenic nerve. Based on these results, it is concluded that DPMPI had several effects on neuromuscular transmission, i.e. it (a) facilitated the transmitter releasing process of the motor nerve terminal, (b) decreased the conduction in the phrenic nerve and (c) increased the directly elicited twitch tension.

Lipocortin-I inhibits the synthesis and release of prolactin from human decidual cells: evidence for autocrine/paracrine regulation by lipocortin-I

The lipocortins are a family of calcium-dependent phospholipid-binding proteins that are induced by glucocorticoids and inhibit phospholipase-A2 activity. To determine whether the lipocortins affect the release of PRL from human decidua, decidual cells from term pregnancies were exposed to recombinant lipocortin-I for 96 h, with medium changes at 24-h intervals. Lipocortin-I (0.01-100 nM) caused a time- and dose-dependent inhibition of PRL release, with a half-maximal effective dose of 50 nM. PRL release was inhibited by 27%, 62%, 93%, and 98% at 24, 48, 72, and 96 h, respectively. The cells exposed to lipocortin-I did not release the enzymes alkaline phosphatase and lactic dehydrogenase, indicating that the inhibitory effect on PRL release was not due to cell death. In addition to inhibiting basal PRL release, lipocortin also completely inhibited the stimulation of PRL release by decidual PRL-releasing factor, a 23.5-kDa protein recently purified from human placenta that stimulates the synthesis and release of decidual, but not pituitary, PRL. Hydrocortisone and dexamethasone (0.1-10 microM) had no effect on PRL release, and arachidonic acid (2-100 microM) inhibited rather than stimulated PRL release. Western blot analysis demonstrated the presence of lipocortin-I in decidual cells and conditioned media. On Northern blot, decidual mRNA hybridized to an oligonucleotide for lipocortin-I. These results strongly suggest that lipocortin-I has an autocrine/paracrine role in regulation of the synthesis and release of PRL from human decidual cells.

Study of the activity of differentiation-induction in a Chinese herb-viscum alniformosanae. Part 1: In vitro induction of differentiation in HL-60 leukemic cell line by conditioned medium secreted from viscum alniformosanae-stimulated mononuclear cells

A conditioned medium(CM), designated as 572-CMF-, was a Chinese herb viscum alniformosanae (V.A.) stimulated mononuclear cells. This CM has the capacity to induce the promyelocytic cell line HL-60 to differentiate into morphologically and functionally mature monocytoid cells. However, our results on the effect of a combination of 572 conditioned medium and IFN-r, TNF and IL-2 were neither synergistic nor additive. Further investigation of the nature of this conditioned medium remains to be performed.

[Screening of antibodies to human T-cell leukemia virus type I (HTLV-I) in sera of blood donors and comparison of different methods]

Nine hundred and sixty five serum samples of blood donors from the blood bank of Veterans General Hospital Taipei were screened for antibodies to human T-cell leukemia virus type I (HTLV-I) by different methods. Adult T-cell Leukemia cell lines MT-1, MT-2, KH-2 and MT-2 stimulated by phorbol 12-myristate 13-acetate (PMA) were used as target cells in immunofluorescence microscopy (IF) examination with positive rates as 0.20% (2/965), 0.62% (6/965), 0.20% (2/965) and 0.51 (5/965) respectively. In addition to these, enzyme-linked immunosorbent assay (ELISA) gave a 2.59% (25/965) positive rate and particle agglutination (PA) test revealed a positive rate of 0.93% (9/965). The samples positive in IF were also positive in PA and those positive in PA were found positive in ELISA without exceptions. The 25 ELISA positive samples as well as 75 samples randomly chosen from the ELISA negative ones received Western blot (WB) analysis as a confirmation test. Only 3 of these 100 were considered positive in WB, giving a final positive rate of 0.31%, (3/965), and all of them were originally positive in both PA and ELISA. Particle agglutination test as the screening test and Western blot analysis as the confirming one were suggested to be a routine procedure for detecting anti-HTLV-I antibodies in blood banks through detailed comparison and discussion.

Hypaque and steroids in the treatment of sudden sensorineural hearing loss

While the origins of sudden sensorineural hearing loss remain unproven and treatment empirical, the most appropriate therapy remains a matter of controversy. In this paper we have analysed the current forms of treatment, i.e. diatrizoate meglumine, steroids and a vasodilator. The results suggest that although several related factors were shown to indicate a good prognosis regardless of the therapy, none of the currently available regimens produces consistently better results than the spontaneous recovery rate of 65% reported by Mattox & Simmons.

A monoclonal antibody against brain calmodulin-dependent protein kinase type II detects putative conformational changes induced by Ca2+-calmodulin

A mouse monoclonal IgG1 antibody has been generated against the soluble form of the calmodulin-dependent protein kinase type II. This antibody recognizes both the soluble and cytoskeletal forms of the enzyme, requiring Ca2+ (EC50 = 20 microM) for the interaction. Other divalent cations such as Zn2+, Mn2+, Cd2+, Co2+, and Ni2+ will substitute for Ca2+, while Mg2+ and Ba2+ will not. The antibody reacts with both the alpha- and beta-subunits on Western blots in a similar Ca2+-dependent fashion but with a lower sensitivity. The affinity of the antibody for the kinase is 0.13 nM determined by displacement of 125I Bolton-Hunter-labeled kinase with unlabeled enzyme. A variety of other proteins including tubulin do not compete for antibody binding. The Mr 30,000 catalytic fragment obtained by proteolysis of either the soluble or the cytoskeletal form of the kinase fails to react with the antibody. Calmodulin and antibody reciprocally potentiate each other's interaction with the enzyme. This is illustrated both by direct binding studies and by a decrease of the Kmapp for calmodulin and an increase in the Vmax for the autophosphorylation reaction of the enzyme. The antibody thus appears to recognize and stabilize a conformation of the kinase which favors calmodulin binding although it does not itself activate the kinase in the absence of calmodulin. Since the Mr 30,000 catalytic fragment of the kinase is not immunoreactive, either the antibody combining site of the kinase must be present in the noncatalytic portion of the protein along with the calmodulin binding site or proteolysis interferes with the putative Ca2+-dependent conformational change.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential diagnosis of chronic lymphocytic leukemia and diffuse well-differentiated lymphoma using monoclonal antibodies

Diffuse well-differentiated lymphocytic lymphoma (DWDL) with leukemic change and chronic lymphocytic leukemia (CLL) are not significantly different in morphology, immunophenotype and clinical course. Two monoclonal antibodies (MoAbs), designated L20 and A01, were established with respective reactivity against DWDL and CLL cells. The L20 MoAb reacted with both DWDL and CLL cells, and 20-50% of normal B cells. The second MoAb, A01, reacted not only with CLL cells but also with 33% of non-T, non-B cells. Immunoprecipitation patterns of L20 and A01 MoAbs against 125I-surface-labeled BALL and Daudi cell extracts revealed respective bands with molecular weights of 86 and 66 kilodaltons. These results showed that DWDL and CLL cells are different in nature, and that these two MoAbs can be used to distinguish DWDL from CLL cells.

Microwave-induced thermoelastic pressure wave propagation in the cat brain

This paper presents direct measurements of acoustic pressure wave propagation in cat brains irradiated with pulsed 2.45-GHz microwaves. Short rectangular microwave pulses (2 microseconds, 15 kW peak power) were applied singly through a direct-contact applicator located at the occipital pole of a cat's head. Acoustic pressure waves were detected by using a small hydrophone transducer, which was inserted stereotaxically into the brain of an anesthetized animal through a matrix of holes drilled on the skull. The measurements clearly indicate that pulsed microwaves induce acoustic pressure waves which propagate with an acoustic wave velocity of 1523 m/s.

Are estrogen receptors cytoplasmic or nuclear? Some immunocytochemical and biochemical studies

The subcellular localization of estradiol receptor (ER) has been examined using various experimental approaches. Immunocytochemical studies using the monoclonal antibody JS 34/32, raised against calf uterine cytosolic ER, yielded only equivocal results. In general, cells and tissues pretreated with estradiol showed positive immunostaining in the nuclei whereas those not exposed to the steroid did not show any staining. Nuclear translocation of ER was examined in intact MCF-7 cells using compounds which are known to influence receptor activation. When MCF-7 cells were exposed to molybdate (20 mM), nuclear translocation was completely inhibited while dithiothreitol (20 mM), dibutyryl cAMP (1 microM) and dibutyryl cGMP (1 microM) increased the translocation 2-3-fold. Phenol red, at the range of concentrations generally used in tissue culture media, also increased translocation. The physiological validity of such translocation was examined using cellular progesterone receptor (PR) synthesis as a specific parameter. When MCF-7 cells were grown in media containing phenol red for 48 h, the PR synthesis increased significantly. We further examined whether cytoskeletal proteins are involved in the translocation of ER. Colchicine, an inhibitor of microtubule assembly, inhibited translocation of ER in MCF-7 cells at 1-10 microM. PR synthesis was also inhibited by colchicine in a dose-dependent manner. It may be concluded from these and other published data that ER may not be located at all times in a single subcellular compartment but may rather exist in a dynamic equilibrium between the plasma membrane, cytoplasm and nucleus.

Monoclonal antibodies against estrogen receptor: interaction with different molecular forms and functions of the receptor

Hybridoma cells have been produced by fusing SP2/O-Ag14 mouse myeloma cells with spleen cells from a mouse immunized with a purified preparation of estrogen receptor from calf uterus. The antibodies, all of the immunoglobulin G (IgG) class, interact with different forms of calf receptor as well as with rat and human receptors. The equilibrium dissociation constant of the antibody-receptor complex was measured in solid phase and in solution. With immobilized antibodies the Kd is 0.06 nM whereas in solution it is 0.5 nM. Only one antigenic determinant is present per molecule of receptor with the antibodies tested. The antibodies JS34/32 are able to form only a 1:1 complex with the 8S form of the receptor, whereas a 2:1 receptor-IgG complex is formed at low antibody concentration with the high-salt or nuclear form of receptor. The antibodies JS34/32 and JS28/32 prevent neither the nuclear uptake of the receptor nor the extraction of the translocated receptor from the nuclei.