Identification of five embryonic hemoglobins of rat and ontogeny of their constituent globins during fetal development

Hemoglobins of rats switch from an embryonic to an adult type during fetal development. However, very little is known about the structures and molecular species of hemoglobins occurring in the fetal life of rats. In the present study we isolated five embryonic hemoglobins, designated E1, E2, E3, E4, and E5, from the blood of rat fetuses on day 14 of gestation by ion exchange chromatography. Reverse-phase high performance liquid chromatography revealed that these hemoglobins each consist of two kinds of globins: E1(11 alpha:epsilon 1), E2(1 alpha: epsilon 1), E3(zetta: epsilon 1), E4(1 alpha: epsilon 3), and E5(zetta: epsilon 3), respectively. The complete amino acid sequences of the zetta, epsilon 1, and epsilon 3 globins were determined. The zetta globin showed characteristic features common in alpha-type embryonic globins of known species in that the N-terminus is blocked and the amino acid at position 38 is Gln. epsilon 1 and epsilon 3 are beta-type embryonic globins, sharing 73.7% amino acid homology. Interestingly, they are more similar to the corresponding mouse beta-type embryonic globins, y and z, respectively, than to each other, implying that these globins have evolved orthologously from common ancestral proteins. It was also shown that the zetta, epsilon 1, and epsilon 3 globins are almost completely replaced by the adult type alpha and beta globins in the blood of rat fetuses by day 18 of gestation.

Changes in calcium transient and left ventricular function during positive inotropic stimulation and myocardial ischemia in indo-1-loaded beating guinea pig heart

To elucidate the issues such as excitation-contraction coupling and myocardial ischemia, it is necessary to measure intracellular free Ca2+ concentration and mechanical function of hearts perfused via the normal arterial circulation. For this purpose, we simultaneously measured Ca(2+)-dependent indo-1 fluorescence and left ventricular (LV) pressure on a beat-to-beat basis in Langendorff guinea-pig hearts, and investigated the changes in Ca2+ transient and LV function during inotropic stimulation and myocardial ischemia. The indo-1 fluoresence ratio and LV developed pressure increased the perfusate [Ca2+] increased from 1.6 to 3.2 mmol/L, and there was a good correlation between Ca2+ transient and LV contractility. Digoxin (10(-6) mol/L) and milrinone (10(-5) mol/L) increased LV contractility with a concomitant increase in Ca2+ transient, and the relative increase of Ca2+ transient produced by milrinone was much more than that by digoxin. The reduction of coronary perfusion pressure from 80 to 40 mm Hg decreased LV contractility with an increase in indo-1 fluorescence ratio. These results suggest that Ca2+ responsiveness of contractile apparatus declines during inotropic stimulation by milrinone and during myocardial ischemia. Thus, this experimental technique is useful to investigate the interrelation of Ca2- regulation and LV function during a variety of pharmacological and physiologic perturbations.

Duodenum-preserving resection of the head of the pancreas: the significance as a diagnostic therapy of the lesion in the pancreatic head

A 75-year-old man who was diagnosed as having mucin-producing pancreatic cystic lesion of the main pancreatic duct by duodenoscopic examination was reported. Because of the low malignant potential of such lesions, duodenum-preserving resection of the head of the pancreas was performed, and the intra-operative histological examination showed no malignancy of the resected pancreatic head and no other surgical procedures, such as lymph-adenectomy nor pancreato-duodenectomy were necessary. The significance of this case report lies in that a less invasive operation should be selected at first to diagnose whether the lesion is malignant or not, and also that the selected operation itself must be sufficient to resect an adequate part of the pancreatic tissue involving the cystic lesion, if not malignant. Here, we report the process to select the procedure and the surgical technique.

Effect of ovariectomy on histological change and protein expression in female mouse reproductive tracts

Proliferation of the vagina and uterus in rodents is stimulated by ovarian estrogen, and ovariectomy induces regression of these tracts. In mouse, reproductive tracts, organ weights, vaginal epithelial thickness, the number of epithelial cell layers, and uterine epithelial cell height were significantly reduced 1 to 20 days after ovariectomy when compared with those of intact, mice taken at the estrous stage. No significant differences in those parameters were found between ovariectomized mice implanted with estradiol and intact estrous mice. Vaginal epithelium at estrus was composed of 10-15 layers of epithelial cells with superficial keratinized layers, however, the vaginal epithelium began to regress one day after ovariectomy. Infiltration of leukocytes was encountered in the vaginal epithelium 2-3 days after ovariectomy. Protein expression in the regressing vagina and uterus after ovariectomy was examined by two-dimensional polyacrylamide gel electrophoresis. After ovariectomy, new proteins appeared in the regressing vagina, but not in the regressing uterus. Expressions of 7 and 6 proteins in the vagina and uterus, respectively, reached peak levels 2-3 days after ovariectomy. The expression of ovariectomy-specific proteins and infiltration of leukocytes in vaginal epithelium was inhibited by the injection of cycloheximide, an inhibitor of protein synthesis. These results suggest that some proteins participate in the regression of mouse reproductive tracts after estrogen withdrawal induced by ovariectomy.

Lack of vasodilatory response in skeletal muscle blood vessels of aged spontaneously hypertensive rats

Regional hemodynamic responses to the vasodilators, hydralazine (1 mg/kg, i.v.) and verapamil (0.1 mg/kg/min, i.v.), were examined in conscious Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR), 15 and 50 weeks of age, using the radioactive microsphere method. The flow rates of heart and skeletal muscle in SHR were higher than those in WKY, and the flow rates of liver, kidney, intestines, and skin in SHR were lower than those in WKY. These differences between the regional blood flow in WKY and SHR were observed in both aged and young rats. The changes in organ blood flow induced by hydralazine and verapamil were similar for WKY and SHR in most organs. Both drugs increased the skeletal muscle blood flow in WKY and young SHR, but not in aged SHR, that is, the skeletal muscle blood vessels in aged SHR lost their vasodilatory response. These results suggest that, although a lack of vasodilatory responses in the skeletal muscle vasculature of aged SHR may be triggered by persistent hypertension, the vital organ vasculature maintains its normal vasodilating capacity.

Kinetically trapped structure in the renaturation of reduced oxindolealanine 62 lysozyme

The refolded products of reduced native lysozyme and reduced OX62 lysozyme, in which Trp62 is converted to oxindolealanine (OX62) during the renaturation of sulfhydryl-disulfide interchange reactions at pH 8 and 37 degrees C, were investigated. On gel-chromatography eluted with 10% aqueous acetic acid containing 4 M urea, two peaks appeared in the refolded product of reduced OX62 lysozyme while a single peak appeared in the refolded product of reduced native lysozyme. From the analyses of the activity and primary and the tertiary structures of the derivative, the structure of the derivative from reduced native lysozyme was confirmed to be identical to that of the untreated one. On the other hand, the refolded product from reduced OX62 lysozyme had the same primary structure but a different tertiary structure compared to the untreated one. The tertiary structure of the refolded product from the reduced OX62 lysozyme was changed to that of the untreated one by the denaturation-renaturation treatment under nonreduced conditions. However, the refolded species was barely changed to that of the untreated one by incubation under physiological conditions. Therefore, the refolded product from reduced OX62 lysozyme was suggested to be a metastable and kinetically trapped product in the renaturation process of reduced OX62 lysozyme. In addition, an interaction involving the folding process of reduced lysozyme was discussed on the basis of the NMR analyses of the metastable structure.

[Primary pulmonary malignant lymphoma of the T-cell type]

A 65-year-old woman was referred to our department because of an abnormal shadow on the chest roentgenogram. The chest roentgenogram showed infiltrative shadows in the right middle and lower lung fields. The chest CT scan showed non-segmental infiltration with a hazy margin and a clear air bronchogram in the right S8 area. A transbronchial aspiration cytology specimen showed atypical lymphocytes, and a transbrochial lung biopsy specimen showed infiltration by atypical lymphocytes. Malignant lymphoma was suspected from the results of the biopsy examination, and a right middle and lower lobectomy was done. The pathological findings showed proliferative atypical lymphocytes in the alveolar and interstitial areas. Malignant lymphoma (diffuse medium cell type by LSG classification) was diagnosed and an immunohistiochemical examination showed monoclonal proliferation of T lymphocytes, which were positive for T lymphocyte surface marker (UCHL-1). Therefore, we believe this was a case of primary pulmonary malignant lymphoma of the T-cell type.

Biological and physicochemical properties of fenitrothion microcapsules as a residual spraying formulation for mosquito control

Insecticidal properties of fenitrothion microcapsules (MC3) as a new residual spraying formulation for mosquito control were studied. Adult female Anopheles albimanus were confined so as to contact several surfaces treated with fenitrothion MC or wettable powder (WP) for 10 and 30 min. Residual efficacy of MC at the rate of 1 g/m2 was almost equivalent to that of WP at the rate of 2 g/m2 on a plywood surface and was superior to that on an unglazed pottery surface. Greater than 50% mortality was maintained for more than 28 wk after treatment by fenitrothion MC on a mud surface with 10 min of contact at the rate of 2 g/m2. The effective duration on a mud surface treated with WP was less than 44 wk with 30 min of contact and was less than 12 wk with 10 min of contact at the rate of 2 g/m2. Microcapsule particles were observed to be mechanically broken (trampled) by mosquito contact, and the amount of fenitrothion released from MC increased as contact time increased. Comparison of MC with WP and emulsifiable concentrate formulations in this study indicates that the increased residual activity results from protection from evaporation and decomposition afforded by capsule walls of the MC formulation.

Mollusk genes encoding lysine tRNA (UUU) contain introns

New intron-containing genes encoding tRNAs were discovered when genomic DNA isolated from various animal species was amplified by the polymerase chain reaction (PCR) with primers based on sequences of rabbit tRNA(Lys). From sequencing analysis of the products of PCR, we found that introns are present in several genes encoding tRNA(Lys) in mollusks, such as Loligo bleekeri (squid) and Octopus vulgaris (octopus). These introns were specific to genes encoding tRNA(Lys)(CUU) and were not present in genes encoding tRNA(Lys)(CUU). In addition, the sequences of the introns were different from one another. To confirm the results of our initial experiments, we isolated and sequenced genes encoding tRNA(Lys)(CUU) and tRNA(Lys)(UUU). The gene for tRNA(Lys)(UUU) from squid contained an intron, whose sequence was the same as that identified by PCR, and the gene formed a cluster with a corresponding pseudogene. Several DNA regions of 2.1 kb containing this cluster appeared to be tandemly arrayed in the squid genome. By contrast, the gene encoding tRNA(Lys)(CUU) did not contain an intron, as shown also by PCR. The tRNA(Lys)(UUU) that corresponded to the analyzed gene was isolated and characterized. The present study provides the first example of an intron-containing gene encoding a tRNA in mollusks and suggests the universality of introns in such genes in higher eukaryotes.

Effect of salt concentration on the pKa of acidic residues in lysozyme

We determined the pKa values of acidic residues in hen lysozyme by comparing the pH dependency of stability between wild type and mutant lysozymes in which a negative charge is eliminated. In the comparison of the stability between wild type and a mutant lysozyme, the difference in pH titration curve between them could be expressed as a two-state process involving protonation of a single acidic residue. The results strongly indicated that the Aune and Tanford theory of protein denaturation [Aune, K.C. and Tanford, C. (1969) Biochemistry 8, 4579-4585] is applicable to protein stability in solution. On the other hand, the pKa values of acidic residues in the presence of low (5 mM) or high (400 mM) salt concentration were determined by means of two-dimensional NMR. We found that the pKa values obtained from the pH dependency of stability were close to those from the NMR experiment under the high salt condition. Moreover, by comparing pKa values at high salt and low salt concentrations, we could evaluate the dependency of two electrostatic interactions (salt bridge and charge-helix dipole interaction) on salt concentration.

Fat emulsions as an ideal nonprotein energy source under surgical stress for diabetic patients

We studied the possibility of fat emulsions being a major calorie source, and if possible, a new infusion protocol without glucose for diabetic patients undergoing surgery. High dosages of fat emulsions and amino acids (HFHA infusions) were investigated as a substitute for conventional glucose-based infusions for 7 days after surgery. Without insulin and glucose, blood glucose was kept within the normal range, in spite of the fact that patients were recovering from major surgeries. Blood triglyceride and fatty free acids (FFA) increased after the start of the HFHA infusions but remained within normal range. Liver function tests and nutritional states estimated by nitrogen balance or rapid turnover proteins were no different from those of the conventional glucose-based infusion, but the significance of the HFHA infusion lies in the fact that it was applied to patients in whom it was impossible to administer enough calories by using the conventional glucose-based infusion, even if insulin was used. This HFHA infusion, which enables easy blood glucose control, sufficient calorie supply without complications, and is also nutritionally equivalent to the conventional glucose-based infusion, can be a new nutritional option for postoperative patients with impaired glucose tolerance.

Immunohistochemical determination of rat spinal cord substance P, and antinociceptive effect during development of thiamine deficiency

During 30 days of thiamine deficiency (TD) feeding, the rat antinociceptive effect (pain threshold) to noxious heat stimulation was significantly increased in proportion to the decrease substance P (SP) fluorescent intensity in the spinal cord. Only a single injection of thiamine HCl (0.5 mg/kg, s.c.) on the early treatment day during TD feeding effectively reversed the analgesic effect to the pair-fed control level. Whereas this reversal effect by thiamine treatment was not found if this treatment was done on the relatively late day. However, either treatment day, except muricide, complete disappearance of various animal behaviours induced by TD was found. These results indicate that, after certain degree of TD development, TD-induced behavioral effects might be reversible, but the afferent nerve fibers might be irreversibly damaged, probably by the similar mechanism as found for an excitotoxin(s) mediated injury in the certain brain region(s). The results also suggest a possibility that SP and an excitotoxin, glutamate, in the dorsal part of the spinal cord greatly contribute to the pain transmission induced by noxious heat stimulation.

Muscarinic receptor agonist-induced increases in cytosolic Ca2+ concentrations in chick ciliary ganglion cells

We used fura-2 microfluorometry to examine the mechanism underlying the muscarinic receptor agonist-induced increase in the cytosolic Ca2+ concentration ([Ca]in) in acutely isolated chick ciliary ganglion neurons. The order of potencies of muscarinic agonists in increasing [Ca]in was: oxotremorine M > muscarine > methacholine > oxotremorine > bethanechol. The muscarine-induced increase in [Ca]in persisted after treatment with thapsigargin, which blocked caffeine- and muscarinic agonist-induced Ca2+ release. The muscarine-sensitive [Ca]in increase was inhibited by both L- and N-type Ca2+ channel blockers but potentiated by an L-type Ca2+ channel agonist. Muscarine was effective in increasing [Ca]in in the presence of a desensitizing concentration of nicotine, and simultaneous addition of maximal doses of muscarine and nicotine caused an additive increase in [Ca]in. On the other hand, nicotine-, ATP-, and high K(+)-induced increase in [Ca]in was markedly potentiated during continuous stimulation with muscarine. These results suggest that muscarinic receptor stimulation increases Ca2+ influx passing through voltage-dependent Ca2+ channels. However, the muscarine-induced Mn2+ influx was observed in only some muscarine-sensitive cells, suggesting that muscarine-induced depolarization is too weak to overcome the inhibitory effect of Mn2+ on Ca2+ channels.

[Two cases of CA19-9 producing pulmonary papillary adenocarcinoma]

Two cases of CA 19-9 producing pulmonary papillary adenocarcinoma were reported. Pathological examination showed a well differentiated papillary adenocarcinoma with partially bronchiolo-alveolar cell type. Immunohistochemical study showed a positive straining for CA 19-9 on tumor cells. The level of CA 19-9 decreased after lobectomy and anti-cancer chemotherapy using CDDP and VDS. The series of CA 19-9 level is very useful to evaluate the effect of surgery and chemotherapy. Also it is useful to find out the recurrence of carcinoma.

[Does a tracheal bifurcation shift upward due to increased intraabdominal pressure during laparoscopic surgery?]

To evaluate the influence of increased intraabdominal pressure on a position of tracheal bifurcation, we measured the distance from the tracheal bifurcation to the tip of the endotracheal tube which is fixed on a patient's mouth during a laparoscopic surgery. The distance decreased from 3.5 +/- 1.9 to 3.1 +/- 1.9 cm (P < 0.05) at mean intraabdominal pressure of 8.7 mmHg. This result suggests that the ventilation may become difficult due to the occlusion of the tip of the endotracheal tube by a tracheal bifurcation or due to inadvertent single lung ventilation under inappropriately deep intubation.

Effect of a calcium-sensitizing positive inotropic agent MCI-154 and its combined use with enalapril on postischemic contractile dysfunction of dog hearts

We wished to elucidate the effects of the calcium-sensitizing positive inotropic agent MCI-154 and its combined use with an angiotensin-converting enzyme (ACE) inhibitor enalapril on postischemic contractile dysfunction. Anesthetized dogs underwent a 30-min occlusion of the left anterior descending coronary artery (LAD) followed by 2 h of reperfusion. Regional myocardial segment shortening in the ischemic LAD area was assessed by sonomicrometry. Myocardial segment shortening decreased in response to the LAD occlusion and remained decreased during 2-h reperfusion. The intravenous infusion of MCI-154 (0.1 or 0.3 micrograms/kg/min) initiated 10 min after occlusion and throughout reperfusion significantly improved the recovery of segment shortening. The alleviation of the postischemic contractile dysfunction by MCI-154 was augmented when the animals were treated with a bous injection of enalapril (0.3 mg/kg) 15 min before ischemia followed by an infusion of the drug (0.003 mg/kg/min). The pretreatment with enalapril alone (0.3 mg/kg plus 0.003 mg/kg/min or 1 mg/kg plus 0.01 mg/kg/min) did not alleviate the postichemic dysfunction, however, although it decreased systemic blood pressure (BP). Ischemic bed size, myocardial necrosis (by triphenyltetrazolium chloride staining), and collateral blood flow (by colored microspheres) were similar in all experimental groups. These results indicate that MCI-154 improves the postischemic contractile function of dog heart, whereas enalapril fails to improve it. ACE inhibitors may also augment the efficacy of cardiotonics on postischemic dysfunction.

Gene of heat shock protein of sulfur-dependent archaeal hyperthermophile Desulfurococcus

To elucidate thermoresistance, a gene of a hyperthermophilic heat shock protein (HHSP) was isolated from the hyperthermophile Desulfurococcus strain SY which grows at 95 degrees C. The molecular weight of HHSP deduced from the open reading frame was 59,137 (545 amino acid residues). Sequence alignments of peptides reveal similarities (evolutionary distances) to the alpha (0.279) and beta (0.296) subunits of thermosome, TF55 (0.343) and human t-complex polypeptide 1. The structure of a thermophilic heat shock protein TGroEL (Tamada et al. (1991) Biochem, Biophys. Res. Commun. 179, 565) was quite different from that of HHSP. TGroEL and HSP60 have sequences identical to HHSP at its equatorial domain, while those identical to the alpha subunit of F-type ATPase are at its apical domain.

Effect of moderately increased intrapelvic pressure on renal tissue pressure and vasopressin release in rabbits

Electrical stimulation of afferent renal nerves and activation of intrarenal receptors increases plasma vasopressin concentration, but the role of afferent renal nerves in the control of vasopressin secretion is not clear. Recently, we reported that activation of renal mechanoreceptors stimulates the release of vasopressin. However, intrapelvic pressure was increased to 50 mmHg, and this increase is above the normal physiological range. Therefore, in the present study, we investigated the effect of moderately increased intrapelvic pressure on plasma vasopressin concentration in anesthetized rabbits. First, we measured renal tissue pressure while intrapelvic pressure was increased stepwise in 10-mmHg increments. Basal renal tissue pressure was 17 +/- 2 mmHg. Renal tissue pressure increased only when intrapelvic pressure was higher than the basal tissue pressure of each animal. Usually, increases in intrapelvic pressure less than 20 mmHg did not increase renal tissue pressure. This finding suggests that only increases in intrapelvic pressure more than 20 mmHg can activate renal mechanoreceptors. Based on this finding, the effects of moderate increases in intrapelvic pressure (15 and 30 mmHg) were studied. With a 15-mmHg increase in intrapelvic pressure, plasma vasopressin concentration did not change significantly. However, when intrapelvic pressure was increased to 30 mmHg, plasma vasopressin concentration increased from 5.6 +/- 1.4 to 9.5 +/- 2.8 pg/ml at 5 min (p < 0.05) and to 8.8 +/- 2.0 pg/ml at 10 min (p < 0.05). Plasma renin activity and mean arterial pressure also increased when intrapelvic pressure was increased to 30 mmHg. We conclude that moderate increases in intrapelvic pressure stimulate vasopressin secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of the multidrug resistance-associated protein (MRP) gene in non-small-cell lung cancer

We examined the levels of expression of the multidrug resistance-associated protein (MRP) gene quantified by Northern blot analysis in comparison with those of the MDR1 gene determined by reverse transcription-polymerase chain reaction (RT-PCR) in 104 non-small-cell lung cancer (NSCLC) specimens [59 adenocarcinoma (Ad), 40 squamous cell carcinoma (Sq), four large cell carcinoma (La) and one adeno-squamous carcinoma (AdSq)]. Thirty-three (31.7%) of the 104 NSCLC expressed the MRP gene at various levels. The NSCLC showing high (++) levels of MRP gene expression (19 out of 33, 57.6%) were predominantly squamous cell carcinomas (Ad, 5; Sq, 13; La, 1) (P < 0.05). Six of the eight NSCLCs expressing high levels of MRP mRNA and no MDR1 (MRP ++, MDR1-) were squamous cell carcinomas. Sixty-one of the 104 NSCLC patients received chemotherapy with MRP-related anti-cancer drugs [vindesine (VDS) and etoposide (VP-16)]. Twenty-three patients (37.7%) with tumour expressing high or moderate levels of MRP showed significantly worse prognoses than those with non- or low-MRP-expressing tumours (P < 0.05). These results suggest that the level of MRP gene expression is related to the histopathology and prognosis of NSCLC.

Alpha 1-adrenergic receptors in cardiac ventricles of Dahl rats

This study was designed to examine the effects of sex, age, and a high-salt diet on cardiac alpha 1-adrenoceptors in an animal model of genetic hypertension, the Dahl salt-sensitive rat. Ventricular alpha 1-adrenoceptors were measured by radioligand binding with [3H]prazosin in membrane fractions in Dahl S and R rats of 7, 12, and 15 weeks of age. In both S and R rats, the maximal binding (Bmax) of alpha 1-adrenoceptor binding was greater in male than in female rats. The Bmax decreased with age in both the S and R strains; at 12 weeks of age, Bmax was approximately one-half of that observed at 7 weeks of age in both S and R strains. In the rats fed a high-salt diet, the Bmax tended to be greater in S rats than in R rats at 12 weeks of age and this difference became significant at 15 weeks of age. A significant positive correlation was found between the Bmax and the heart-to-body weight ratio in the Dahl S and R rats. The dissociation constant (Kd) was not different between male S and R rats at each age. These results suggest that the ventricular alpha 1-adrenoceptor may be involved in cardiac hypertrophy in Dahl rats.

Effects of enriched and impoverished housing environments on the electrocorticograms (ECoGs) of middle-aged rats

Electrocorticograms (ECoGs) were evaluated in young rats and in middle-aged (19 months) rats housed under three different environments. The standard condition (SC, N = 5) indicated the condition where two rats stayed in a standard cage, enriched condition (EC, N = 5) meant keeping 6-8 rats in a large cage and impoverished condition (IC, N = 5) was referred to as housing a single rat in a small cage. All middle-aged rats were kept under one of these cage conditions for 12 months, starting at 7 months of age. An ECoG was recorded simultaneously from 6 different locations on the scalp and was subjected to comparisons among the SC, EC and IC by means of spectral analysis. The power of the occipital alpha band (8.1-10.0 Hz) was significantly increased in IC rats. Total occipital power in IC rats was also enhanced as compared to SC and EC rats. These findings demonstrate that ECoG changes are present in the neocortex of middle-aged rats in different environments. In addition, social interaction seems to have a stronger effect than the differences in living capacity. These results indicate that the aging process should be studied from the viewpoint of environmental influences.

Acute myeloblastic leukaemia without Philadelphia chromosome developing after interferon therapy for chronic myelocytic leukaemia with Philadelphia chromosome

We report a patient who developed Philadelphia chromosome negative acute myeloblastic leukaemia with trisomy 8 and trisomy 11 after receiving treatment with alkylating agents and interferon for chronic myelocytic leukaemia positive for Philadelphia chromosome. Leukaemic cells were positive for myeloperoxidase and expressed CD13, CD33 and DR; some expressed CD2, CD4 and CD34. The fluorescence in situ hybridization method revealed that bcr-abl fusion genes were absent from > 90% of the bone marrow cells. The major bcr rearrangement was not detected by Southern blot analysis. We conclude that the leukaemic cells negative for Philadelphia chromosome may have developed as a result of treatment with alkylating agents and interferon in the present case.

Membrane-associated lymphotoxin-expressing lymphokine-activated killer cells up-regulate intercellular adhesion molecule-1 expression on target tumor cells in vitro

Human lymphokine-activated killer (LAK) cells cultured with interleukin-2 express membrane-associated lymphotoxin (mLT) on the cell surface. mLT-lacking (mLT-) LAK cells, which are generated by culturing without IL-2 for 24 hr, fully retained natural killer (NK) and LAK activity. However, they partially lost their killing activity against various tumor cells when compared to mLT-expressing (mLT+) LAK cells. An anti-LT but not anti-tumor necrosis factor (TNF) antibody somewhat suppressed the killing activity of mLT+ LAK cells against these tumor cells. However, an anti-LT antibody did not alter NK or LAK activity of mLT+ LAK cells. Anti-CD18 (beta chain of LFA-1) and anti-CD54 (ICAM-1) monoclonal antibodies, by inhibiting LAK cell binding to targets, suppressed the killing activity of mLT+ LAK cells. During the process in the cytotoxic assay, mLT+ but not mLT- LAK cells up-regulated ICAM-1 expression on target tumor cells, the effect of which was marginally inhibited by anti-TNF and anti-IFN-gamma but not by anti-LT antibodies. The up-regulation of ICAM-1 expression elicited by LAK cells on target tumor cells was not simply caused by diffused soluble factors but required membrane contact of LAK and target cells. Paraformaldehyde-fixed mLT+ but not mLT- LAK cells up-regulated ICAM-1 expression on target cells. These findings indicate that mLT+ but not mLT- LAK cells up-regulate ICAM-1 expression on target tumor cells via undetermined membrane factor(s), and this effect appears to be at least partially responsible for the higher killing activity of mLT+ LAK cells than that of those lacking mLT in vitro.

A right ventricular hemopump restores right ventricular function with pulmonary artery banding

We investigated the ability of the Hemopump to support the right ventricle during acute, partial, pulmonary artery obstruction. In 6 pigs, a 14 Fr size Hemopump was placed through the pulmonary artery into the right ventricle. Control measurements were made. A band around the pulmonary artery proximal to the outflow port of the Hemopump was tightened, and measurements were repeated with the Hemopump at minimum and then maximum speed. With banding, right ventricular stroke volume and output decreased (43 [SD, 7] to 28 [SD, 8] ml, p < 0.001; 4.9 [SD, 0.8] to 3.7 [SD, 1.0] L/min, p < 0.01 respectively), but they were restored with the Hemopump (38 [SD, 5] ml and 4.5 [SD, 0.6] L/min; both p = NS vs control). Increases in right ventricular peak systolic (28 [SD, 10] to 42 [SD, 17] mm Hg; p < 0.01) and end-diastolic pressure (2 [SD, 1] to 12 [SD, 6] mm Hg; p < 0.02) were reversed by the Hemopump (29 [SD, 8] and 4 [SD, 2] mm Hg; both p = NS vs control). Right ventricular pressure rate product almost doubled with banding (3,199 [SD, 1,252] to 5,962 [SD, 2,796] mm Hg; p < 0.01), but it decreased with the Hemopump (3,368 [SD, 767] mm Hg; p = NS vs control). With acute partial pulmonary artery banding, a right ventricular Hemopump restores output from and offloads the right ventricle.