Separation of albumin from autologous plasma by heat

A simplified technique has been developed to separate albumin from the plasma of a patient undergoing treatment with plasma exchange. This albumin can be returned to the patient to maintain colloid osmotic pressure without risk of transmitting disease. Patient plasma is obtained by apheresis. It is heated at 70 degrees C for 60 minutes to denature and remove autoantibodies, immune complexes, and abnormal globulins. The resulting low-concentration albumin solution (LCAS) retains its natural properties. Immunologic analysis by gel diffusion shows a reaction pattern of complete identity with that of human serum albumin. The albumin in LCAS is more than 90 percent of the remaining protein, as determined by scan of a cellulose acetate electrophoresis pattern. More than 97 percent of the albumin is in monomer form, as judged by polyacrylamide gel electrophoresis. No patient antibodies to neonantigens in the heat-treated albumin can be identified by double radial immunodiffusion. More than 80 percent of the plasma albumin is recovered in LCAS. LCAS is safe and efficient for use in plasma exchange.

Closure mechanisms of laryngeal vestibule during swallow

This study examined the temporal effects of bolus volume on closure of the laryngeal vestibule at the arytenoid to epiglottic base and the mobile portion of the epiglottis, the temporal relationships between these levels of airway closure and cricopharyngeal opening for various bolus volumes, and the mechanisms responsible for these two levels of airway protection during deglutition. Closure of the laryngeal vestibule progressed inferiorly to superiorly at all bolus volumes. Duration of closure of the airway at the arytenoid to epiglottic base increased systematically with bolus volume, as did the duration of descent of the epiglottis below horizontal. Closure at the arytenoid to epiglottic base occurred earlier in relation to maximal laryngeal elevation as bolus volume increased. In contrast, descent of the epiglottis to horizontal and the temporal relationship between closure of the airway at the arytenoid to epiglottic base and cricopharyngeal opening were independent of bolus volume. These findings indicate a tightly organized neural program for some pharyngeal swallow events with systematic variability with volume in other pharyngeal events, possibly modulated by afferent input from the periphery. The neuromuscular mechanisms responsible for closure of the airway at the arytenoid to epiglottic base and at the mobile epiglottis appear to be quite different. Closure at the arytenoid to epiglottic base is apparently under direct neural control by active anterior tilting of the arytenoid cartilage and posterior projection of the epiglottic base as the larynx elevates, whereas epiglottic downward movement to closure is the biomechanical effect of hyolaryngeal movement, downward bolus movement, and tongue base retraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical localization of progesterone receptor in human decidua of early pregnancy

Rat monoclonal antibodies to human progesterone receptor were used for immunolocalization studies in human decidua of early pregnancy. Frozen sections of 42 specimens of decidua were stained by the peroxidase-antiperoxidase method (PAP). Progesterone receptor was localized exclusively in the nuclei of decidual and myometrial cells with no specific staining in the cytoplasm. In the decidualized endometrium, stroma were always positively stained. Smooth muscle, pericyte and endothelial cells of blood vessels were extensively stained. Glandular epithelia showed variation in staining, which was positive in the basal but very weak or negative in the superficial layer of the decidua. No specific staining could be detected in the control sections. Of special interest was the positive staining of the endothelium of decidual blood vessels, a finding which has not been reported previously. The cells of the inner lining of vessels that stained with the antiprogesterone receptor antibodies were also Factor VIII positive, thus confirming the endothelial nature of these cells. It is concluded from these results that endothelial cells from human first trimester decidua express progesterone receptors.

Suppression of acute lymphoblastic leukemia by the human wild-type p53 gene

Independent mutations in both alleles of the p53 tumor suppressor gene are a frequent finding in human T-cell acute lymphoblastic leukemia (T-ALL) cell lines and in the cells of some T-ALL patients in relapse. One major goal of studying the status of p53 (and other tumor suppressor genes) in human cancer is to facilitate the suppression of the tumorigenic phenotype through the restoration of the expression of the wild-type allele. While the efficient insertion of a suppressor into all cells of solid/metastatic human tumors may at present be impossible, insertion into leukemia cells may be feasible due to the accessibility of the leukemia cells in the body. To examine the feasibility of suppressing the tumorigenicity of human T-leukemia cells, the human T-ALL cell line Be-13, which lacks endogenous p53 protein, was infected with a recombinant retrovirus encoding the wild-type allele of human p53 (hwtp53). Expression of p53 reduced the growth rate of infected Be-13 cells in vitro, suppressed colony formation in methylcellulose cultures, and abrogated their tumorigenic phenotype in nude mice in vivo. These results suggest that suppression of the leukemic phenotype of relapse T-ALL-derived Be-13 cells is feasible. Acute leukemia cell suppression via high-efficiency infection with retroviruses encoding wtp53 may be feasible and beneficial in T-ALL cases as part of a bone marrow transplantation regimen in an effort to reduce the frequency of posttransplantation relapse.

Genetic influences in opioid analgesic sensitivity in mice

Studies of various strains of mice revealed marked differences in their analgesic sensitivity towards morphine (mu), U50,488H (kappa 1) and naloxone benzoylhydrazone (NalBzoH; kappa 3). Sensitivity to mu and kappa analgesia varied independently of the other. Analgesic sensitivity to morphine remained relatively consistent among 3 different nociceptive assays for each strain. However, the sensitivity of an individual strain to NalBzoH remained highly dependent upon the assay used. CD-1 mice were sensitive to NalBzoH in all 3 assays, but in BALB/c mice NalBzoH produced analgesia only in the hot plate and cold water tail-flick assays. In Swiss-Webster mice, NalBzoH was active in the radiant heat and cold water tail-flicks but inactive in the hot plate. Although the levels of mu, kappa 1 and kappa 3 binding in whole brain homogenates did vary somewhat, they did not correlate with analgesic sensitivity. These results suggests that the genetic controls over mu and kappa analgesia operate independently and further illustrate the many difficulties in evaluating potential analgesics.

Binary arithmetic using optical symbolic substitution and integrated phototransistor surface-emitting laser logic

We outline an architecture for performing binary addition by using optical symbolic substitution and optical logic gates based on heterojunctionphototransistors and verticalcavity surface-emitting lasers.

Observation of the activity of factor VIII in the endometrium of women pre- and post-insertion of three types of IUDs

The endometrial materials were obtained from 90 women who had been randomly inserted with three types of IUDs (Stainless steel ring, SS; copper T 220, TCu 220, and levonorgestrel-releasing device, LNG). An immunoperoxidase reaction, PAP method, with the antiserum of Factor VIII as the primary antibody, was carried out to detect the Factor VIII activity in the endometrial endothelium pre- (control) and post-insertion of the IUDs. The results revealed that: 1. There was a generalized lower Factor VIII activity in the endometrium of women post-insertion of IUDs (except LNG). 2. Comparison of the Factor VIII activity in the endometrium of women using different types of IUDs showed that the TCu type and the SS type decreased the activity significantly whereas the activity remained unchanged after 3-6 months' use of the LNG-IUD. The different types of IUDs seemed to influence the coagulation regulatory system in different ways; the lower Factor VIII activity, the more tendency to bleeding. 3. The Factor VIII activity in the endometrium of women using IUDs was lower in all phases of the menstrual cycle including the proliferative phase when the Factor VIII activity is normally high. It cannot be excluded that this could be a contributing factor to IUD-induced bleedings.

Effects of spatial dispersion of acetylcholine release on AV conduction responses to vagal stimulation in dogs

We determined the effects on atrioventricular (AV) conduction of changing the spatial dispersion of acetylcholine (ACh) release from vagal nerve fibers in anesthetized dogs. We paced the atria at a constant rate and stimulated the vagus nerves with one stimulus burst per cardiac cycle. We varied the spatial heterogeneity of ACh release in the cardiac tissues by changing the stimulus voltage, and we varied the quantity of ACh release from each excited nerve fiber by changing the number of pulses per stimulus burst. We slightly changed the stimulus timing with each heartbeat to scan the entire cardiac cycle. We constructed phase-response curves (PRCs) by plotting the changes in AV conduction time as a function of the timing of vagal stimulation. We found that the amplitude of the PRC varied directly with average AV conduction time (AV), whereas the minimum-to-maximum phase difference of the PRC varied inversely with AV. However, for any given change in AV, the specific characteristics of the PRCs did not depend on whether we varied the number of pulses per burst or the stimulus voltage. Therefore, the phase-dependent characteristics of the dromotropic responses appear to be unaffected by the spatial dispersion of ACh release from the vagal nerve endings. The effects of vagal activity on the AV conduction time are determined by those conducting fibers that are the least restrained by neurally released ACh.

Endosonographic TNM staging of extrahepatic bile duct cancer: comparison with pathological staging

Endosonography was performed preoperatively in 33 patients with common bile duct carcinoma and in 43 patients with carcinoma of the common hepatic duct and its bifurcation. The results were correlated with the histology of resected specimens according to the new (1987) TNM (tumor, node, metastasis) classification. Endosonography was accurate in the evaluation of the depth of tumor infiltration. Overall accuracy for common bile duct carcinoma and common hepatic duct carcinoma was 82.8% and 85%, respectively. Endosonography was helpful in diagnosing regional lymph node metastases but not accurate in diagnosing nonmetastatic lymph nodes. With common bile duct carcinoma, the incidence of lymph node metastasis increased with progressive depth of tumor infiltration. No such correlation was found in common hepatic duct carcinomas. In the staging of distant metastasis, this technique was limited by the low-penetration depth of ultrasonography. Thus, additional transcutaneous ultrasonography or computed tomography was necessary for complete staging. The routine use of the biopsy channel for endosonographically guided aspiration puncture will further enhance the diagnostic value of endosonography in the future.

[Research and application of SUPER-1 intellectural instrument used in physiology laboratory]

Research work for making a biomedical signal processing instrument based on the APPLE-II computer is reported in this paper. According to the theory of the computer, two interface boards were designed as the hardware of the instrument. The memorizing waveform program was designed as the main program in the software system. Through a functional extended program, also called software inter face, more than ten programs especially for physiology can be easily linked to the main program. with the combination of both the software and hard ware several parameters of the instrument, such as sampling speed, gain of the amplifier, etc. can be controlled by a closed loop. This instrument is available in the physiology laboratory to replace oscilloscope, recorder, stimulator simultaneously. The functions of the instrument are stronger than those of the conventional instruments.

Lectin histochemistry of cystic jaw lesions: an aid for differential diagnosis between cystic ameloblastoma and odontogenic cysts

The binding sites for Ulex europaeus agglutinin I (UEA-I), Bandeirea simplicifolia agglutinin I (BSA-I), and peanut agglutinin (PNA) were comparatively examined in the surgical materials from 41 cases of cystic and solid ameloblastomas and 42 cases of non-neoplastic odontogenic cysts including dentigerous cyst, odontogenic keratocyst, and radicular cyst. In non-neoplastic cysts, most of epithelial lining layers gave positive binding with UEA-I and BSA-I. However, no positive reactions were obtained for these two lectins in the epithelial components of ameloblastoma, except for limited UEA-I binding to markedly keratinized tumor cells in four cases. PNA binding was irregular and did not make any clear distinction between ameloblastomas and cysts. The results suggest that the lectin staining for UEA-I and BSA-I is a useful histologic aid for differential diagnosis between cystic ameloblastoma and non-neoplastic jaw cysts.

Opioids regulate the release of human chorionic gonadotropin hormone from trophoblast tissue

Opioid ligands were investigated for their effect on hCG release from trophoblast tissue obtained from term human placenta. Data obtained indicate that opiate agonists stimulate in vitro basal hCG release from trophoblast tissue. The potency of these opioid agonists correspond to their kappa receptor selectivity, i.e., the greater the selectivity the lower is the effective concentration causing maximum stimulation. Opioid antagonists inhibit the release of hCG due to their reversal of the stimulation caused by endogenous opioid peptides. Potency of the antagonists correspond also to their kappa receptor selectivity. Antagonists reverse the stimulation of hCG release caused by agonists indicating that the ligand's action is mediated by the placental kappa opioid receptors. The bell shaped response curves for agonists and antagonists suggest that opioids play a role in the regulation of hCG release from trophoblast tissue, but other mechanism(s) may also exist.

[Effects of amino acids on the membrane potential of toad oocytes and the underlying mechanism]

Of the 23 amino acids tested for their effect on the membrane potential of incubated toad oocyte, alanine, leucine and lysine were found to cause a decrease of polarization (depolarization) and K+ permeability, while tryptophan causes an increase of potential (hyperpolarization) and K+ permeability. For the rest 19 amino acids, no membrane effects were observed. Accompanying the alanine, leucine and lysine caused depolarization, the oocyte progesterone content became doubled and the maturation process hastened. These effects could be completely blocked by 1 mmol/L dibutyryl cAMP (db-cAMP) or 50 mumol/L estradiol. Tryptophan on the other hand could block the progesterone (10 mumol/L) induced depolarization but had no effect on the db-cAMP induced hyperpolarization. The regulatory function of the amino acids and steroid hormones underlying oocyte maturation is discussed.

Frequent mutations in the p53 tumor suppressor gene in human leukemia T-cell lines

Human T-cell leukemia and T-cell acute lymphoblastic leukemia cell lines were studied for alterations in the p53 tumor suppressor gene. Southern blot analysis of 10 leukemic T-cell lines revealed no gross genomic deletions or rearrangements. Reverse transcription-polymerase chain reaction analysis of p53 mRNA indicated that all 10 lines produced p53 mRNA of normal size. By direct sequencing of polymerase chain reaction-amplified cDNA, we detected 11 missense and nonsense point mutations in 5 of the 10 leukemic T-cell lines studied. The mutations are primarily located in the evolutionarily highly conserved regions of the p53 gene. One of the five cell lines in which a mutation was detected possesses a homozygous point mutation in both p53 alleles, while the other four cell lines harbor from two to four different point mutations. An allelic study of two of the lines (CEM, A3/Kawa) shows that the two missense mutations found in each line are located on separate alleles, thus both alleles of the p53 gene may have been functionally inactivated by two different point mutations. Since cultured leukemic T-cell lines represent a late, fully tumorigenic stage of leukemic T cells, mutation of both (or more) alleles of the p53 gene may reflect the selection of cells possessing an increasingly tumorigenic phenotype, whether the selection took place in vivo or in vitro. Previously, we have shown that the HSB-2 T-cell acute lymphoblastic leukemia cell line had lost both alleles of the retinoblastoma tumor suppressor gene. Taken together, our data show that at least 6 of 10 leukemic T-cell lines examined may have lost the normal function of a known tumor suppressor gene, suggesting that this class of genes serves a critical role in the generation of fully tumorigenic leukemic T cells.

Effects of the spatial dispersion of acetylcholine release on the chronotropic responses to vagal stimulation in dogs

We determined the effects of changing the spatial dispersion of acetylcholine release on the phase-dependent chronotropic responses to vagal stimulation in anesthetized dogs. We stimulated the vagus nerves with one brief burst of electrical pulses each cardiac cycle, and we changed the timing of the stimulus by a small, constant amount each cardiac cycle to scan the entire cycle. To vary the heterogeneity of acetylcholine release, we changed the voltage of the stimulus pulses over a range of submaximal values. To achieve the maximum homogeneity of acetylcholine release, we used supramaximal voltages, and we varied the level of acetylcholine release from each excited fiber by changing the number of pulses per burst. We used the average cardiac cycle length of the phase-response curve to assess the overall vagal effect, independent of its timing within the cardiac cycle. We found that the amplitude of the phase-response curve varied directly and the minimum-to-maximum phase difference varied inversely with the overall efficacy of vagal activity. However, for any given alteration in the overall efficacy, the specific changes in the characteristics of the phase-response curve did not depend on whether the alteration was achieved by varying the number of pulses per burst or by varying the stimulus voltage. Therefore, we conclude that although the cardiac chronotropic response is very sensitive to changes in the timing of vagal stimulation, it is not influenced appreciably by the spatial dispersion of acetylcholine release from the vagal nerve endings over a wide range of stimulation strengths.

Clogging of biliary endoprostheses: a new perspective

Endoscopic palliation with biliary endoprostheses is now an established treatment for benign and malignant strictures of the biliary tree. These endoprostheses, however, tend to clog with time. We investigated this problem by undertaking in vitro studies on stents of different designs made of different polymer materials. The stent that performed best was then tested in an in vivo trial. There was a direct relation in vitro between the frictional coefficient of a polymer and the amount of encrusted material. Catheters perfused in bacterially contaminated bile, irrespective of material and design, accrued significantly more sludge than catheters perfused with sterilised bile. The presence of side holes significantly increased the amount of sludge in the stents, but eliminated any differences between the various materials. We therefore investigated the effect of omitting side holes in a clinical trial which consisted of two groups of 20 patients each. The group treated with conventional stents accrued significantly more sludge in the stents than the group treated with experimental stents without side holes (p less than 0.05). The absence of side holes did not cause incomplete drainage or increase morbidity. Side holes are detrimental to stent patency, which is adversely affected by other factors including bacteria and proteins.

New Taxanes from Taxus chinensis

Two new taxane diterpenes, decinnamoyltaxagifine ( 3) and decinnanioyltaxagifine acetate ( 2), have been isolated from the leaves and stems of TAXUS CHINENSIS. Their structures were elucidated by spectroscopic methods. Their (13)C-NMR chemical shifts were assigned.