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D C Jackson

Publications and source records attributed to D C Jackson.

At least 127 records · Page 7Linked to original sources
PubMed1982

Antigenic determinants of influenza virus hemagglutinin--IX. The carbohydrate side chains from an Asian strain.

The heavy chain (HA1) of hemagglutinin from the Asian variant A/Japan/305/57 was examined to establish which of the four oligosaccharide units on this polypeptide could cross-react with host antigen. Cyanogen bromide and enzymic digests were fractionated and the resulting peptides screened for their ability to bind to antibodies raised against uninfected chick chorioallantoic membranes. This 324 residue HA1 polypeptide from the Asian strain A/Japan/305/57 is known to contain oligosaccharide units at asparagine residues 11, 23, 285 and at either 164, 165 or both. The peptides carrying the four carbohydrate units have been isolated, the monosaccharide compositions determined and the location of the fourth oligosaccharide shown to be Asn164 by direct amino acid sequence analysis. All four sugar units on A/Japan/305/57 HA1 are of the N-acetyllactosamine type, but only the one attached to Asn11 could cross-react with anti-(host antigen) antibodies. This antigenic carbohydrate unit on the Asian hemagglutinin heavy chain is located in a similar region to the two antigenically active oligosaccharides located on the hemagglutinin from the Hong Kong variant A/Memphis/102/72. The study was therefore extended to include the early Hong Kong variant A/Aichi/2/68, which has the same oligosaccharide distribution as A/Memphis/102/72 but different sugar compositions for the individual oligosaccharide units Like A/Memphis/102/72, only the N-acetyllactosamine units attached at positions 8 and 22 of A/Aichi/2/68 were capable of binding to anti-(host antigen) IgG. Finally, the light chain (HA2) polypeptides from A/Bel/42 (HO), the A/Japan/305/57 (H2) and the two Hong Kong variants A/Aichi/2/68 (X-31) and A/Memphis/102/72 were also examined and found to contain carbohydrate which is antigenically related to chick embryo host antigen.

Carbohydrates↗
PubMed1982

Enumeration of antigenic sites of influenza virus hemagglutinin.

The antigenic sites on the hemagglutinin of X-31 (H3) influenza virus have been defined by using a competitive radioimmunoassay with a panel of monoclonal antibodies which includes those known to select variants with substitutions of particular amino acids. The capacity of each monoclonal antibody to block the binding of other radioiodinated monoclones to purified hemagglutinin permitted classification of the panel into four separate groups, each of which defined a particular antigenic site on the hemagglutinin molecule. Three of these are located on the polypeptide backbone and correspond to the "hinge," the "loop," and the "tip/interface" of the X-ray crystallographic model of Wiley et al. (Nature [London] 289:373-378, 1981). Nonreciprocal blocking of certain anti-interface antibodies by anti-loop antibody suggests that much of the exposed surface of the head of the hemagglutinin molecule extending from the loop to the interface may be a continuum of epitopes. A fourth antigenic site is carbohydrate in nature, presumably situated on the antigenic oligosaccharide side chains. These four domains are in addition to two antigenic sites defined by monoclonal antibodies that inhibit neither hemagglutination nor infectivity (Breschkin et al., Virology 113:130-140, 1981;' Yewdell et al., Nature [London] 279:246-248, 1979).

Antibodies, Monoclonal↗
PubMed1982

Long-term submergence at 3 degrees C of the turtle Chrysemys picta bellii in normoxic and severely hypoxic water. III. Effects of changes in ambient PO2 and subsequent air breathing.

Western Painted Turtles, Chrysemys picta bellii (N = 5), were maintained submerged and apneic for 90 days: days 0-21 in severely hypoxic water (PO2 = 0-5 mmHg), days 22-43 in aerated water (PO2 approximately 160 mmHg), and days 44-90 again in hypoxic water. From day 90 onward, the water was aerated and the turtles were allowed access to the air; water and air temperatures were maintained at 3 degrees C. Arterial blood samples were taken periodically and analysed for PO2, PCO2, pH, [Na+], [K+] [Cl-], [lactate-], [glucose] and haematocrit. Plasma [HCO3-] was calculated for all samples and total plasma calcium was measured on samples from two animals. Each exposure to low PO2 water caused progressive lactic acidosis and a transient respiratory acidosis with an accompanying fall in plasma [Cl-] and rise in plasma [K+] and [calcium]. During the intervening period in aerated water, blood pH recovered significantly (from 7.33 to 7.74 in 7 days), due primarily to a fall in PCO2 (from 23.5 to 10.6 mmHg), while [lactate-] remained unchanged (at about 50 mM), and [HCO-3] rose slightly. Plasma [K+] promptly returned to nearly normal values. When permitted to breathe on day 90, the three surviving turtles rapidly restored pH to normal by pronounced hyperventilation (PCO2 less than 5 mmHg). Metabolic acidosis, however, disappeared slowly with a t1/2 for [lactate-] and [HCO-3] restoration of about 2 weeks. We conclude that a wintering turtle can stabilize or even slightly improve its acid-base and ionic status by moving from an anoxic environment to well-oxygenated water. Further improvements can be gained by breathing air, but recovery proceeds at a very slow rate if the animal remains at 3 degrees C.

Acclimatization↗
PubMed1981

Acid-base balance and temperature in a predominantly skin-breathing salamander, Cryptobranchus alleganiensis.

Blood gases and pH and plasma [Na+], [K+], [Cl-] and [lactate] were measured on arterial blood of the large predominantly skin-breathing salamander, the hellbender (Cryptobranchus alleganiensis), at 5, 15 and 25 degrees C, both with and without access to air. Access to air had no effect of any of the acid-base variables, but temperature had significant effects on both pH and PCO2. Blood pH decreased with temperature by about 0.016 unit/degrees C both in vivo and in vitro (over the range studied) which is similar to the change previously observed on other ectotherms. Blood PCO2 rose significantly with temperature while plasma [HCO-3] rose slightly but insignificantly. Other ions were unaffected by temperature. This is the first demonstration that the characteristics ectothermic acid-base response to temperature occurs in a vertebrate respiring exclusively through its skin. We suggest that the response in this animal is essentially passive and uncontrolled and is due to: (1) the proportional effects of temperature upon metabolic CO2 production and blood PCO2, and (2) the temperature-independent CO2 conductance of the skin.

Acid-Base Equilibrium↗
PubMed1981

Antigenic determinants of influenza virus haemagglutinin. VI. Antigenic characterization of the oligosaccharide sidechains form HA1 of influenza virus haemagglutinins.

The oligosaccharide sidechains attached to the major polypeptide, HA1 of the haemagglutinin of influenza virus were examined for antigenic activity using a solid-phase radioimmunoassay. Cross-reactivity between the HA1 of the different human subtypes was clearly demonstrable with IgG raised against purified virus but was abrogated if anti-carbohydrate antibodies were first removed by passage of the IgG through an immunoadsorbent column containing haemagglutinin (HA) from an unrelated avian influenza strain. Antibodies eluted from the column were found to cross-react with the HA1 of all subtypes tested. 'Host antigen' extracted from chick chorioallantoic membrane and coupled to Sepharose was also able to remove cross-reactive antibodies from antiviral sera, while antibodies raised against host antigen bound to the HA1 isolated from each subtype tested. It is concluded that, although there are qualitative and quantitative differences between the oligosaccharide sidechains of influenza haemagglutinins, the antigenically active sidechains are cross-reactive.

Cross Reactions↗
PubMed1981

In vitro antibody response to influenza virus. II. Specificity of helper T cell recognizing hemagglutinin.

Intraperitoneal immunization of mice with liver influenza virus was shown to induce helper T (TH) cells with specificity for the hemagglutinin (HA). The interaction of virus-primed TH cells with purified HA was studied independently of B cell reactivity to the same antigen by using the generation of nonspecific help as an index of activation of HA-specific TH cells. TH cells from mice primed with any of the H3 viruses A/Aichi/68 X A/Bel/42 (H3N1), A/Memphis/102/72 X A/Bel/42 (H3N1) or A/Port Chalmers/73 (H3N2) were strongly cross-reactive towards HA of other strains within the H3 subtype. In addition, several examples of cross-reactivity towards HA of a different subtype were observed, usually of a lower magnitude. TH cells from mice primed to any of the H3 viruses above or to A/Bel/42 (H1N1) virus cross-reacted with the HA of A/Japan/305/57 (H2); furthermore, priming with A/Bel/42 or with A/Jap/305/57 X A/Bel/42 (h2N1) virus yielded TH cells that cross-reacted with certain of the H3 HA preparations. The cross-reactivity observed between subtypes was not due to the common chicken host carbohydrate component of HA, since no response to the purified type A HA preparations was obtained with T cells from mice primed with egg-grown influenza B/Hong-Kong/8/73 virus. The results indicate that HA of different subtypes may share cross-reactive antigenic determinants recognized by TH cells. Within a subtype, HA are highly cross-reactive with respect to tH cell recognition.

Animals↗
PubMed1980

Skin circulation of the frog, Rana catesbeiana: distribution and dynamics.

The volume and distribution of blood flow to the skin of the bullfrog, Rana catesbeiana, from both the pulmocutaneous and systemic arterial sources were measured. Radioactively labelled microspheres (35 +/- 5 micron) were used to map the regional distribution of each of these sources and to measure the systemic blood flow to the skin during air breathing and diving. Cutaneous artery blood flow was measured with an ultrasonic (Doppler) flowmeter. The systemic supply to the skin perfuses predominantly the limbs, while the largest cutaneous artery supply is to the back and flanks of the animal. All regions received blood from both sources. The cutaneous artery blood flow decreased during diving to approximately one-third of the pre-dive level. This decrease, however, was offset by an approximately equivalent increase in systemic blood flow to the skin during diving. These data should reconcile the decrease in pulmocutaneous blood flow and the important function of the skin as a gas exchanger during diving.

Animals↗
PubMed1980

Epidural anesthesia in aortofemoral arteriography.

The experience with a well-established regional anesthetic technique i.e., epidural anesthesia for alleviating pain during aortofemoral arteriogrpahy is described. Of 59 patients, 51 experienced no subjective or objective evidence of pain, while eight patients subjectively reported mild burning pain during injection of contrast. Apart from patient satisfaction, important additional benefits of epidural anesthesia were excellent filling of both distal small arteries and collateral vessels around obstructing arterial lesions. Complications were few and insignificant. It is concluded that epidural anesthesia is a safe procedure that not only eliminates pain, but also gives better quality radiographs.

Adult↗
PubMed1980

Acute gastrointestinal hemorrhage of small-bowel origin.

Of 305 patients with acute gastrointestinal (GI) bleeding, the site was found to be the small bowel in 16. In all cases the cause was proved at surgery or autopsy: diagnoses included vascular malformation, aorto-enteric fistula, primary or metastatic tumor, ulcer, tuberculous ileitis, and sarcoidosis. While it is uncommon for acute GI bleeding to originate in the small bowel, approximately one third of the patients with acute rectal bleeding in this series had a bleeding site in the small bowel.

Adult↗
PubMed1980

The incidence, etiologies, and avoidance of complications of pulmonary angiography in a large series.

Pulmonary angiography is sensitive and specific in the diagnosis of pulmonary thromboembolism, but it remains an invasive procedure. Experience with 1,350 pulmonary angiograms was reviewed to ascertain the incidence, etiologies, and avoidance of complications. There were three deaths, all of which were secondary to cor pulmonale in patients with pulmonary hypertension and right ventricular end diastolic pressure (RVEDP) equal to or greater than 20 mmHg. Other complications consisted of cardiac perforation in 14 patients and endocardial or myocardial injury in six without sequelae, 11 significant arrhythmias and five cardiac arrests successfully treated, minor contrast material reactions in 11 patients, and a few insignificant complications. Carefully performed pulmonary angiography is safe if one avoids injecting contrast material into a patient with an elevated RVEDP.

Angiocardiography↗
PubMed1980

Angiographic evaluation of chronic pulmonary embolism.

In some patients acute pulmonary emboli may fail to resolve normally, resulting in chronic pulmonary embolism. This may lead to pulmonary hypertension, respiratory insufficiency, cor pulmonale, and death. The angiographic evaluation in nine patients with chronic pulmonary embolism who underwent embolectomy is presented. Particular emphasis on the predictive value of selective bronchial arteriography in four of these patients is considered. In chronic pulmonary embolism, pulmonary arteries distal to obstructed areas may remain patent and be supplied by hypertrophied bronchial arteries. Since back-bleeding of arterial blood from the bronchial circulation at surgery may predict the success of embolectomy, preoperative bronchial arteriography may be useful for predicting potential surgical success.

Adult↗
PubMed1980

Temperature effects on ventilation and acid-base balance of the green turtle.

Ventilation (VE), pulmonary gas exchange (MO2 and MCO2), and arterial acid-base status (pH and PaCO2) were measured in immature green turtles. Chelonia mydas, equilibrated at 15, 25, and 35 degrees C. From 25 to 35 degrees C, pH decreased by 0.0134 U/degrees C and PaCO2 increased from 30.1 +/- 1.1 to 46.0 +/- 2.4 Torr (mean +/- SE, n = 8) in conformity with results from other ectotherms. From 15 to 25 degrees C, however, pH fell on the average by 0.06 U/degrees C but the change was not significant. PaCO2 rose over this range from 25.3 +/- 1.6 to 30.1 +/- 1.1 Torr. Calculated plasma [HCO3-], 27-28 meq/l, did not change over the entire temperature range. Both VE and MO2 increased with temperature, but the ratio, VE/MO2 (the air convection requirement), fell with temperature (1.01 +/- 0.10 l/mmol at 35 degrees C, 0.64 +/- 0.03 l/mmol at 25 degrees C, and 0.45 +/- 0.04 l/mmol at 15 degrees C). We conclude that the green turtle adheres to the typical ectotherm blood acid-base pattern over their usual temperature range (25-35 degrees C), but that pH control deviates from this pattern at temperatures below this range.

Acid-Base Equilibrium↗
PubMed1980

Antigenic determinants of influenza virus hemagglutinin. V. Antigenicity of the HA2 chain.

All the polypeptide fragments obtained by cyanogen bromide cleavage of the hemagglutinin from A/Memphis/102/72 influenza virus were examined for their ability to bind to IgG raised against purified virus. Within the hemagglutinin heavy chain the only fragment displaying antigenicity is HA1CN1, which comprises the amino-terminal 168 amino acid residues. By the use of a sensitive radioimmunoassay in which the antigen is unlabeled, it was shown that the light chain is also antigenic. Inhibition studies have localized the activity to the HA2CN1 region, which comprises the carboxy-terminal 90 amino acids. The determinant on HA2 is shown to be subtype specific.

Antibodies, Viral↗
PubMed1979

Microsphere studies of bullfrog central vascular shunts during diving and breathing in air.

Bidirectional central vascular shunts were measured during diving and breathing in air in unanesthetized bullfrogs by using pulmonary trapping of 38 mu mean diameter radionuclide-labelled microspheres. Six animals studied during diving exhibited a strong overall right-to-left shunting pattern comprised of both a predominant (68% mean) right-to-left shunt and a weak (23%) left-to-right countershunt. Five animals with access to air showed a variety of distribution patterns, including predominant shunts in the left-to-right (1 animal) and right-to-left (1 animal) directions, nearly complete mixing (2 animals) and separation of systemic and pulmonary venous returns (1 animal).

Animals↗
PubMed1979

Ventilatory response to inspired CO2 in the sea turtle: effects of body size and temperature.

The ventilatory response of green turtles (Chelonia mydas) to inspired CO2 was tested. Both immature (0.9--1.35 kg) and adult (59--130 kg) animals responded with increased ventilation (VE) that was primarily (immature) or exclusively (adult) due to increased respiratory frequency. The VE of the immature turtles while breathing air increased with temperatures between 15 and 35 degrees C with a Q10 of 1.95, but the peak VE of these turtles while breathing 4.5% CO2 in air was not significantly different at 15, 25 or 35 degrees C. VE increased irregularly with time throughout an hour of CO2 breathing in both groups, although several of the adult animals exhibited a first-breath response to CO2 and all animals increased VE within 5 min after the onset of CO2 breathing. The VE of an immature turtle at 35 degrees C increased with graded increases in CO2 up to 6%, but at 15 and 25 degrees C VE increased only up to 4.5% and decreased with 6% CO2. The results are discussed in terms of possible receptor mechanisms involved.

Aging↗
PubMed1979

Antigenic determinants of influenza virus hemagglutinin. II. Antigenic reactivity of the isolated N-terminal cyanogen bromide peptide of A/Memphis/72 hemagglutinin heavy chain.

Gel filtration of a cyanogen bromide digest of pure intact hemagglutinin from A/Memphis/102/72 influenza virus allowed the isolation of a variety of fragments. One of these fragments consists of three cyanogen bromide peptides (CNl and CN3 from HA1, and CNl from HA2) which remain linked together by disulphide bonds. This fragment was found to be antigenically active, as it was able to form antigen-antibody complexes (detected by affinity chromatography of radioiodinated peptide-IgG mixtures on protein A-Sepharose) with IgG directed against the protein moiety of viral hemagglutinin. The three cyanogen bromide peptides present in this disulphide-linked fragment were separated by gel filtration, carried out under reducing conditions, and tested for antigenic activity after controlled reoxidation of the individual peptides. Only one cyanogen bromide peptide, CNl from HA1, showed significant binding to antibody. The results indicate that antigenic activity of A/Mem/1O2/72 hemagglutinin resides within the N-terminal 170 amino acid residues of the hemagglutinin heavy chain.

Antibodies, Viral↗