The nucleotide sequence of a microvitellogenin encoding gene from the tobacco hornworm, Manduca sexta

A microvitellogenin (mVg)-coding gene (mvg) has been isolated from a lambda phage library prepared from the tobacco hornworm, Manduca sexta. One of the lambda clones had a 15-kb insert and contained the entire mvg gene. A DNA fragment (3.0 kb) containing this mvg gene has been sequenced. Southern blot analysis showed that there may be more than one mvg gene in M. sexta. The putative transcriptional start point (tsp) for the cloned mvg was determined by primer extension analysis. This gene contains a single intron in the 5'-noncoding region. The 5'-flanking sequence was compared to the 5'-conserved regions of yolk polypeptide-encoding genes (yp) of Drosophila melanogaster. Two regions were found in the 5'-flanking sequence of the mvg gene that have 66% similarity to the D. melanogaster yp consensus sequence that is believed to be involved in gene expression controlled by ecdysteroids. Furthermore, the sequences flanking these two regions are also similar to the ecdysone-responsive elements found in several genes of D. melanogaster. In fact, preliminary experiments showed that mVg mRNA synthesis is induced by the 20-hydroxyecdysone. Four regions of the mvg gene resemble the upstream conserved regions of the two vitellogenin-encoding genes of the locust, Locusta migratoria. The nucleotide sequence of mvg has 70% similarity to the sequence of one or more of the 30-kDa hemolymph proteins of Bombyx mori. This indicates a very close evolutionary relationship between these proteins.

[Female infertility due to tubal obstruction--management and clinicopathologic study of 66 cases]

Sixty-six cases of female infertility due to obstruction of fallopian tubes from December 1984 to June 1988 were analysed. A discrepancy of 28.8% existed between hysterosalpingography and operative findings, e. g. X-ray revealed blocked tubes, but during operation the tubes were found to be patent. The abnormal and marked tortuosity giving rise to resistance to the passage of oil at the ampullar portion of tubes in the majority of cases may be the explanation. Pathological examination of 48 specimens revealed the chief cause of obstruction was nonspecific infection (50.0%). The next tuberculous infection (31.3%). The third isthmic nodular salpingitis (6.25%) and the fourth endometriosis (4.2%). Operative procedures were done for the purpose of ovum pick-up and to treat the diseased tubes. Three cases of clinical pregnancy as the result of intra-operative ovum pick-up in a program of IVF/ET occurred after 1987 when our IVF technology gradually improved. This result suggests that operation on the tubes did not jeopardize the process of implantation. Among the 14 cases followed up for more than one year 3 cases became pregnant. Operations to relax and straighten up the tortuous part of the tubes or instillation of fluid into the tubes and transplantation of the healthy tube into the single horn uterus were effective. To do an anastomosis on the chronically inflamed and thickened tubes was not helpful.

Pancreatic digestive enzyme gene expression: effects of CCK and soybean trypsin inhibitor

Regulation of pancreatic gene expression by cholecystokinin (CCK) was examined in the rat using cloned cDNA probes to quantify changes in specific mRNAs (amylase, trypsinogen I, chymotrypsinogen B, and ribonuclease). Rats were administered intraduodenally an elemental liquid diet. Plasma CCK levels were raised to levels comparable to physiological postprandial levels either by intraduodenal perfusion with soybean trypsin inhibitor (SBTI) (6.9 +/- 1.0 pM, n = 8) or by continuous intravenous infusion with cholecystokinin octapeptide (CCK-8, 6.0 +/- 0.9 pM, n = 6). SBTI infusion resulted in fivefold increases in trypsinogen I and chymotrypsinogen B mRNA levels after 48 h. In contrast SBTI infusion had no effect on amylase mRNA levels and led to a decrease in ribonuclease mRNA levels to approximately 50% of control after 48 h. Intravenous infusion with CCK-8 for 24 h resulted in plasma levels of CCK comparable to those obtained with SBTI and had similar effects on digestive enzyme mRNA levels. These data suggested that SBTI acted via its ability to raise plasma CCK levels. To further test the specificity of these effects, animals were infused intraduodenally with the specific CCK receptor antagonist L364,718. Although the antagonist itself had no effect on digestive enzyme mRNA levels, antagonist treatment totally abolished the effects of both CCK infusion and SBTI treatment. These data therefore indicate that CCK regulates digestive enzyme gene expression at plasma concentrations comparable to physiological postprandial levels. Furthermore, the ability of SBTI infusion to increase plasma CCK accounts for its effects on pancreatic digestive enzyme mRNA levels.

[A new leptospiral serovar in the autumnalis serogroup]

Strain A6 of leptospire was isolated from blood culture of a case with leptospirosis on July 1, 1962 in Mengla county, Xishuangbanna, Yunnan. It is proved a new serovar belonging to serogroup Autumnalis by cross agglutination and cross agglutinin-absorption tests. The name, Leprospira interrogans serovar nanla with reference strain A6 is proposed.

Aircraft noise-induced temporary threshold shift

Audiograms were taken on 20 young men before and immediately after exposure to Fighter-6 ground running-up noise, and their course of recovery was followed. The sound levels at the engine hatch were 117-128 dB(A). The noise-induced temporary threshold shift was more than 13 dB. The maximum threshold shift occurred at 4 kHz. The shift in the low and speech frequencies recovers more rapidly and is completed in 30 min, whereas that in the high-frequency range recovers much more slowly, not returning to normal until 24 h later. High-frequency hearing loss is at risk in groundcrew. In order to prevent hearing damage, they ought to wear ear-protectors. We discovered that the V-shaped depression was not at 4 kHz but at 6 kHz. The former view concerning the pathogenesis of "4 kHz depression", therefore, is open to question. This interesting subject warrants further study.

[Diabetic osteopathy (an analysis of 37 cases)]

This paper reported the result of clinicoradiologic analysis of 37 patients with diabetic osteopathy. The site of predilection was the bony ends of the extremities, especially the foot (91.9%). The main clinical manifestation was the presence of a non-healing chronic ulcer, whereas diabetic gangrene of bone constituted the chief x-ray finding, which was characterized by osteolytic destruction at the bony ends of metatarsals and phalanges, with minimal periosteous reaction if any. The bony articular surfaces were usually preserved. The chief distinction to be made is osteomyelitis. The mechanism of diabetic osteopathy is most probably systemic metabolic disorders resulted from disturbance of carbohydrate metabolism with secondary neurovascular changes. Infection probably plays the role of enhancing effect in gangrene of bone.

Copper vapor laser and optical fiber catheter system for liquefaction and removal of thrombus in occluded arteries

An instrument consisting of a copper vapor laser coupled to an optical fiber/chemical injector catheter for the treatment of occluded arteries has been constructed and tested. The combined application of three steps: the pre-irradiation injection of a light absorbing dye, HPD; brief copper laser irradiation (at 578 nm); and a urokinase infusion after the irradiation, produced the striking effect of liquefaction and resolution of thrombus. The histological examination of the arteries after the treatment showed no apparent damage to the arterial wall.

Liquid chromatographic determination of L-ascorbate 2-polyphosphate in fish feeds by enzymatic release of L-ascorbate

An accurate method was devised to assay L-ascorbic 2-polyphosphate esters (AsPP) in fish feed by phosphatase digestion followed by determination of the released L-ascorbic acid (AsA). Compressed yeast and dithiothreitol are added to the phosphatase reaction mixture to give 95-100% recovery of AsA, which is quantitated by reverse-phase liquid chromatography (LC) with electrochemical detection. Chromatograms of all feed digests showed baseline resolution of AsA. In 3 feeds, to which 75-125 ppm AsA equivalents in the form of AsPP were added, the assay procedure gave 98-100% recovery of AsA.

cDNA cloning and deduced amino acid sequence of microvitellogenin, a female specific hemolymph and egg protein from the tobacco hornworm, Manduca sexta

Microvitellogenin is a female-specific yolk protein from the tobacco hornworm moth Manduca sexta. A cDNA library was constructed from poly(A)+ RNA isolated from adult female fat body. cDNA clones of mRNA for microvitellogenin were isolated by using antiserum against microvitellogenin. Northern blot analysis of poly(A)+ RNA isolated from different life stages and sexes reveals that mRNA coding for microvitellogenin is only present in adult female fat body. Immunoprecipitation of the protein product translated from hybrid selected mRNA indicates that the cDNA clone is specific for microvitellogenin. The complete nucleotide sequence of the 834-base pair cDNA insert has been determined by the dideoxy chain termination method. The cDNA sequence predicts that microvitellogenin is a protein of 232 residues with a calculated molecular weight of 26,201. The cDNA also predicts an amino-terminal extension of 17 residues which are not present in the mature form. This sequence appears to be a signal peptide. A comparison of the translated amino acid sequence with the sequences in the National Biomedical Foundation protein library did not establish any sequence homology with other known proteins.

Growth hormone promoted tyrosyl phosphorylation of growth hormone receptors in murine 3T3-F442A fibroblasts and adipocytes

Because many growth factor receptors are ligand-activated tyrosine protein kinases, the possibility that growth hormone (GH), a hormone implicated in human growth, promotes tyrosyl phosphorylation of its receptor was investigated. 125I-Labeled human GH was covalently cross-linked to receptors in intact 3T3-F442A fibroblasts, a cell line which differentiates into adipocytes in response to GH. The cross-linked cells were solubilized and passed over a column of phosphotyrosyl binding antibody immobilized on protein A-Sepharose. Immunoadsorbed proteins were eluted with a hapten (p-nitrophenyl phosphate) and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The eluate from the antibody column contained an Mr 134,000 125I-GH-receptor complex. A similar result was obtained when the adipocyte form of 3T3-F442A cells was used in place of the fibroblast form. O-Phosphotyrosine prevented 125I-GH-receptor complexes from binding to the antibody column, whereas O-phosphoserine and O-phosphothreonine did not. In studies of GH-promoted phosphorylation in 3T3-F442A fibroblasts labeled metabolically with [32P]Pi, GH was shown to stimulate formation of a 32P-labeled protein which bound to immobilized phosphotyrosyl binding antibodies. The molecular weight of 114,000 obtained for this protein is similar to that expected for non-cross-linked GH receptor. The Mr 114,000 phosphorylated protein could be immunoprecipitated with anti-GH antibody, indicating that GH remained noncovalently bound to this protein during absorption to and elution from the immobilized phosphotyrosyl binding antibody. Phosphoamino acid analysis after both limited acid hydrolysis and extensive base hydrolysis of the Mr 114,000 phosphoprotein confirmed the presence of phosphotyrosyl residues.(ABSTRACT TRUNCATED AT 250 WORDS)

Freeze-fracture cytochemistry of rat glomerular capillary tuft. Determination of wheat germ agglutinin binding sites and localization of anionic charges

We propose here the use of freeze-fracture to gain access and to label in vitro glomerular components and locate WGA receptors and anionic sites. Tissues are frozen, fractured under liquid nitrogen, and thawed. Freeze-fracture rendered all glomerular structures directly accessible to the reagents. This made possible study of the nature and topology of cationized ferritin and WGA binding sites. WGA-gold complexes were observed over plasma membranes of podocytes and of endothelial and mesangial cells. Labeling of podocytes and endothelial cells was similar in the mesangial area and in the peripheral part of the capillary loop. Cross-fractures of extracellular matrices showed that WGA bound uniformly to the glomerular basement membrane (GBM) as well as to mesangial matrix. In fractured specimens treated with neuraminidase, WGA was no longer observed over podocytes but it consistently labeled the surface of endothelial and mesangial cells. Whereas in GBM cross-sections WGA binding was greatly reduced or even abolished, it remained unmodified in the mesangium. This shows that only NeuNAc (sialic acid) might account for the binding of WGA to podocytes, whereas GlcNAcs appear to be the main WGA binding sites on endothelial and mesangial cells and in the mesangial matrix. Both NeuNAc and GLcNAc residues are probably associated in GBM. With cationized ferritin (pI 8.3) at pH 7.4, intense, continuous labeling was seen all over the different plasma membranes, denser in podocytes than in endothelial cells. CF was also observed in cross-fractured profiles of extracellular matrices and never appeared agglutinated in discrete sites.

Nalbuphine as an analgesic component in balanced anesthesia for cardiac surgery

The efficacy and safety of nalbuphine hydrochloride as an IV analgesic used in combination with pretreatment and supplemental doses of diazepam with and without N2O were assessed in 15 patients scheduled to undergo aortocoronary bypass (n = 11) or valve replacement surgery (n = 4). The loading infusion of 3.0 mg/kg nalbuphine given in 20 min 5 min after conclusion of IV injection of 0.4 mg/kg/5 min diazepam caused no significant changes in systolic or diastolic systemic and pulmonary arterial blood pressures or in heart rate, cardiac index, stroke index, systemic and pulmonary vascular resistance, or right and left ventricular stroke work index. After the initial 1-hr loading infusion of 6.66 +/- 0.89 mg/kg nalbuphine (mean +/- SE), additional nalbuphine infusion maintenance doses of 4.73 +/- 0.77, 1.87 +/- 0.31, 2.16 +/- 0.23, 1.65 +/- 0.22, and 2.35 +/- 0.44 were used in the subsequent hourly periods to maintain a pain-free state throughout surgery. Hemodynamic changes during the three most stressful periods, tracheal intubation, skin incision, and sternotomy, were not statistically significant. Normal plasma catecholamine and cortisol levels indicate that these patients experienced neither stress nor pain during the maintenance of anesthesia. Nalbuphine caused no significant histamine release. All patients had uncomplicated maintenance of and emergence from anesthesia.

Endocrine and hemodynamic effects of antagonism of fentanyl-induced respiratory depression by nalbuphine

Endocrine and hemodynamic changes associated with the antagonism of fentanyl by nalbuphine have not been reported. Therefore, the authors studied ten patients after anesthetic induction with thiopental, fentanyl, tracheal intubation aided by succinylcholine and maintenance with diazepam, pancuronium, N2O, and further doses of fentanyl. Eight of the patients underwent cholecystectomy, one had a hysterectomy, and another had an abdominoplasty. After reversal of neuromuscular block at the conclusion of surgery, normal ventilation was restored by 0.22 +/- 0.02 mg/kg intravenous nalbuphine (mean +/- SEM). Plasma levels of free norepinephrine, histamine, and cortisol did not increase after antagonism of the fentanyl-induced respiratory depression, but plasma concentration of epinephrine increased significantly but without significant hemodynamic changes. Minute ventilation was 1.5 +/- 0.4 L/min before and 11 +/- 1, 10 +/- 1, 11 +/- 1, and 10 +/- 1 L/min at 15, 30, 45, and 60 min after antagonism; corresponding PaCO2 levels were 56 +/- 2, 44 +/- 1, 49 +/- 7, 49 +/- 1, 42 +/- 1 mm Hg. The mean analogue pain score remained below 1.5. We conclude that nalbuphine effectively antagonizes fentanyl-induced respiratory depression without adverse endocrine and circulatory changes or loss of analgesia.