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Antisense oligodeoxynucleotides [oligo(dN)] have the ability to enter living cells and block the expression of specific genes. However, little is known about the mechanism of cellular uptake of oligo(dN). We have found that oligo(dN) can bind to the cell membranes of eukaryotic cells with much greater efficiency under acidic conditions (pH 4.0-4.5) than at neutral pH. The binding appears to be specific to poly nucleic acids since various sizes of oligo(dN), DNA and RNA, but not mononucleotides, compete for the binding. We have identified a 34 kDa membrane protein from T-cells, which binds to oligo(dT) cellulose at pH 4.5 and can be eluted at pH 7.5. This protein fraction blocked the binding of oligo(dN) to living T-cells in a competitive fashion. Our results suggest that eukaryotic cells have a receptor for oligo(dN) at acidic pH and that the 34 kDa dalton protein on the cell membrane may mediate such binding.

A case of chronic pancreatitis in an 8-year-old boy with glycogen storage disease type 1a (GSD 1a) is presented. This patient had a history of hyperlipidaemia unresponsive to dietary therapy, e.g., a carbohydrate-rich diet, uncooked cornstarch, and nocturnal intragastric tube feedings. He had recently suffered bouts of abdominal pain and diarrhoea. Serum amylase and trypsin were elevated, abdominal CT revealed the presence of a pseudocyst of the pancreas. The presence of chronic pancreatitis was confirmed by endoscopic retrograde cholangiopancreatography and an infected pseudocyst was removed at laparotomy.

To clarify the relationship between hyperbilirubinaemia and abnormal results of biochemical liver function tests in infants with breast milk jaundice (BMJ), 58 breast-fed infants with indirect hyperbilirubinaemia were enrolled in this study. Sera obtained from the above infants were subjected to routine liver function tests. Although serum transaminases were within normal limits in all 58 patients, serum alkaline phosphatase levels were abnormally increased in 13, gamma-glutamyltranspeptidase in 8 and total bile acids in 11 out of all patients examined. A total of 18 (31%) patients had abnormal results in at least one item of the liver function tests. The intrinsic bile acid loading test showed postprandial increases in bile acids in 5 of 16 (31%) patients examined at either 60 or 120 min, while all 13 breast-fed, age-matched controls had no abnormal results. The decrease in rate of serum bilirubin levels after the 3-day discontinuation of breast-feeding was significantly less in patients with increased fasting bile acids than in patients with normal fasting levels of serum bile acids. These results may suggest that mild hepatic dysfunction or cholestasis is associated with indirect hyperbilirubinaemia in some infants with BMJ.

Characteristics of the vascular course of ruptured vessels in the submucosal layer of Dieulafoy ulcer were studied, and endoscopic hemostatic treatment was performed using Aethoxysklerol and ethanol. 1) Observations of vessel courses in serial sections revealed that ruptured vessels in Dieulafoy ulcer exhibit rhexis in the lateral portions of the vessel and long courses over the ulcer margin in the submucous layer. 2) More dependable hemostasis seemed to be provided by thrombosis not only at the source of bleeding. i.e., at the site of vessel rupture, but also in the region of the whole ruptured vessel in the submucous layer. 3) Hemostatic treatment by local injection of Aethoxysklerol and ethanol was performed in 4 patients with Dieulafoy ulcer, and complete hemostasis was achieved in all 4 patients.

1. The distribution of isozymes of 5'-nucleotide phosphodiesterase (E.C.3.1.4.1) was examined in various organs of mouse, including liver, spleen, pancreas, heart, lung, kidney, brain and blood. 2. Five isozymes were identified and designated as isozymes I through V. 3. These isozymes are distributed unevenly with respect to the various organs and clear differences were observed in the patterns of distribution among the organs examined. 4. The level of these isozymes was compared in serum of neonate and adult mice, and a higher level of isozyme I and a lower level of isozyme IV were found in neonates compared to adults. 5. These results suggest that each isozyme has different functional roles in individual organs and that these isozymes may be involved in proliferation and development of cells.

The X gene product of human hepatitis B virus (HBV) trans-activates the HBV enhancer. In order to identify domains responsive to trans-activation by the X gene, we introduced a series of mutations into the HBV enhancer and assayed the enhancer activities in the presence of the X gene product. Our results suggest that the EP domain of the enhancer is essential for trans-activation by the X gene.

Calorie-protein deficiency affects humoral immunity in the chicken. Secondary responses to sheep-red blood cells, a T-dependent antigen, were lower in birds fed diets two-thirds deficient in calories (C), amino acids (AA), or both (C/AA). These results led us to question what effects might be found in cell-mediated immunity after nutritional deficiency. Birds fed the same diets as in our previous study showed no reduction in total white blood cells, absolute lymphocytes, or absolute heterophils. Splenic lymphocytes from 3- or 7-week-old nutritionally deficient chickens with the exception of the AA group at 7 weeks, produced a nonsignificant increase in graft-versus-host (GvH) response of 12-day-old embryos. Thymic cells from 3-week-old nutritionally deficient birds were not deficient in the GvH potential. Thymic histology revealed reduced cellularity in AA-deficient birds. The reduced cellularity may not have been in response to stress since the mean corticosterone levels were not significantly different. Birds fed the deficient diets for 10 weeks had a significantly reduced delayed hypersensitivity response to human gamma globulin. The results indicate that the chickens' ability to produce a GvH response was not compromised and that T-cell subpopulations may have differential sensitivities to nutritional deficiencies.

The plasmid pBS2 has a low copy number and is endogenous to Bacillus subtilis. The replication of this plasmid depends on the function of most of the host's dna genes including dnaB, which is unique to B. subtilis and is required for both the initiation of chromosome replication and the DNA-membrane association. We have identified the region that is essential for the replication of pBS2 and determined the complete 2279-bp nucleotide sequence of this region. In this region, there are two stretches of sequence homologous to the 18-bp consensus sequence which commonly appears at the origin of replication of plasmids pUB110 and pC194. The entire region contains six sizable open reading frames. Two of them are probably translated. One open reading frame, designated ORF A, coding for 269 amino acids, has significant homology, in terms of amino acid sequence, with the open reading frame of the gene for the Rep U protein of plasmid pUB110. The similarities between pBS2 and other plasmids suggest that the pBS2 may also replicate as a rolling circle, which appears to be the salient feature of a mechanism of replication that is common to small plasmids in gram-positive bacteria.

Delayed hypersensitivity (DH) reactions by chickens to human gamma globulin (HGG) were influenced by age. Chickens 6 to 12 weeks of age exhibited a significantly greater DH reaction than 3-week-old chickens. The injection of HGG 1, 2, or 3 weeks after sensitization did not significantly influence the DH reactions. Our data allow us to reject the hypothesis that there is no significant age difference in the DH response of chickens.

Mononuclear cells collected by Ficoll-paque or T cells collected by nylon wool elicited the same magnitude of graft versus host (GvH) response as mononuclear cells collected from the buffy coat (BC). Bone marrow, spleen, or thymic BC cells from day-old chickens did not produce a GvH response. The GvH ability of spleen and bone marrow BC cells increased rapidly during the first 4 weeks and then plateaued. Although at 4 and 12 weeks of age the GvH response produced by thymic BC cells was significantly less than spleen or bone marrow BC cells, thymic BC cells did produce a significant GvH response at these ages. Thymic BC cells from 11-month-old chickens showed significantly higher GvH response than those of previous ages. Corticosterone treatment of chickens eliminated the thymic cortex but did not enhance the GvH reactivity of thymic BC cells. Suppressor effect of thymic BC cells from day-old chickens was not detected. A synergistic effect was noted in the GvH reaction when thymic cells were combined with bone marrow or splenic BC cells of 4-week-old chickens.