The haptoglobin-gene deletion responsible for anhaptoglobinemia.

We have found an allelic deletion of the haptoglobin (Hp) gene from an individual with anhaptoglobinemia. The Hp gene cluster consists of coding regions of the alpha chain and beta chain of the haptoglobin gene (Hp) and of the alpha chain and beta chain of the haptoglobin-related gene (Hpr), in tandem from the 5' side. Southern blot and PCR analyses have indicated that the individual with anhaptoglobinemia was homozygous for the gene deletion and that the gene deletion was included at least from the promoter region of Hp to Hpr alpha but not to Hpr beta (Hpdel). In addition, we found seven individuals with hypohaptoglobinemia in three families, and the genotypes of six of the seven individuals were found to be Hp2/Hpdel. The phenotypes and genotypes in one of these three families showed the father to be hypohaptoglobinemic (Hp2) and Hp2/Hpdel, the mother to be Hp2-1 and Hp1/Hp2, one of the two children to be hypohaptoglobinemic (Hp2) and Hp2/Hpdel, and the other child to be Hp1 and Hp1/Hpdel, showing an anomalous inheritance of Hp phenotypes in the child with Hp1. The Hp2/Hpdel individuals had an extremely low level of Hp (mean+/-SD = 0.049+/-0. 043 mg/ml; n=6), compared with the level (1.64+/-1.07 mg/ml) obtained from 52 healthy volunteers having phenotype Hp2, whereas the serum Hp level of an individual with Hp1/Hpdel was 0.50 mg/ml, which was approximately half the level of Hp in control sera from the Hp1 phenotype (1.26+/-0.33 mg/ml; n=9), showing a gene-dosage effect. The other allele (Hp2) of individuals with Hp2/Hpdel was found to have, in all exons, no mutation, by DNA sequencing. On the basis of the present study, the mechanism of anhaptoglobinemia and the mechanism of anomalous inheritance of Hp phenotypes were well explained. However, the mechanism of hypohaptoglobinemia remains unknown.     

Collagenase and collagenolytic cathepsin in normal and fibrotic rat liver

Collagenase and collagenolytic cathepsin activities in normal and carbon tetrachloride-induced fibrotic livers of rats were simultaneously determined at 35 and 25 degrees C for 18 h, using the same 14C-labeled neutral soluble collagen as a substrate. Collagenolytic cathepsin had higher activity under the assay conditions at both 35 and 25 degrees C than collagenase in normal and fibrotic livers. On sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis, the collagen was visibly degraded by collagenolytic cathepsin, but not by collagenase. These results indicate that, unlike collagenase, collagenolytic cathepsins exist as active forms in the rat liver, and can participate in the degradation of collagens, especially of soluble collagens including procollagens.     

Glucose-dependent insulinotropic polypeptide (GIP) stimulation of pancreatic beta-cell survival is dependent upon phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB) signaling, inactivation of the forkhead transcription factor Foxo1, and down-regulation of bax expression

The hormone glucose-dependent insulinotropic polypeptide (GIP) potently stimulates insulin secretion and promotes beta-cell proliferation and cell survival. In the present study we identified Forkhead (Foxo1)-mediated suppression of the bax gene as a critical component of the effects of GIP on cell survival. Treatment of INS-1(832/13) beta-cells with GIP resulted in concentration-dependent activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB)/Foxo1 signaling module. In parallel studies, GIP decreased bax promoter activity. Serial deletion analysis of the bax promoter demonstrated that the region -682 to -320, containing FHRE-II (5AAAACAAACA), was responsible for GIP-mediated effects. Foxo1 bound to FHRE-II in gel mobility shift assays, and Foxo1-FHRE-II interactions conferred GIP responsiveness to the bax promoter. INS-1 cells incubated under proapoptotic and glucolipotoxic conditions demonstrated increased nuclear localization of Foxo1 and bax promoter activity and decreased cytoplasmic phospho-PKB/Foxo1. GIP partially restored expression PKB/Foxo1 and bax promoter activity. Similar protective effects were found with dispersed islet cells from C57BL/6 mice, but not with those from GIP receptor knock-out (GIPR(-/-)) mice. GIP treatment reduced glucolipotoxicity-induced cell death in C57 BL/6 and Bax(-/-) islets, but not GIPR(-/-) mouse islets. Chronic treatment of Vancouver diabetic fatty Zucker rats with GIP resulted in down-regulation of Bax and up-regulation of Bcl-2 in pancreatic beta-cells. The results show that PI3K/PKB/Foxo1 signaling mediates GIP suppression of bax gene expression and that this module is a key pathway by which GIP regulates beta-cell apoptosis in vivo.     

A novel tetrameric short tandem repeat located in the 3' flanking region of the human ABO-secretor gene (FUT2) and association between FUT2 and FUT2/01 loci

We found a novel polymorphic short tandem repeat (FUT2/01), 3.8 kb downstream of the coding region of FUT2. Seventeen length and 33 sequence variants were identified in 300 individuals representing three major human populations. Africans (Xhosa) and Europeans were characterized by high microvariation, and Japanese were characterized by a simple repeat structure. All exhibited high haplotype diversity.     

An autopsy case of epignathus (immature teratoma of the soft palate) with intracranial extension but without brain invasion: case report and literature review

Background

Epignathus is a rare congenital orofacial teratoma infrequently associated with intracranial extension. Intracranial extension of an epignathus indicates a poor prognosis; however, only a small number of such cases have been reported. While there have been some studies reporting cases of epignathus expanding directly into the cranium, others have reported no communication between an epignathus and an intracranial tumor.

Case presentation

A fetus at gestational week 27 was suspected of having an epignathus with intracranial tumor as shown by ultrasonographic and magnetic resonance imaging. The fetus was stillborn and an autopsy was performed. An epignathus measuring 12?×?6?×?6?cm and weighing 270?g protruded from the mouth, with its base on the soft palate. An intracranial tumor weighing 14?g was located at the middle intracranial fossa and connected to the epignathus through the right side of the sella turcica. The intracranial tumor was encapsulated, and there was no invasion into the brain. Histologically, both the epignathus and intracranial tumor were immature teratomas, with neural and pulmonary components that were especially immature as compared to those of the internal organs and brain tissues of the fetus.

Conclusion

There have been several reports of epignathus and intracranial tumors that did not communicate; therefore, careful evaluation is needed when a fetus is suspected of having an epignathus extending into an intracranial lesion. Our case supports the findings that an epignathus can directly expand into the cranium. Moreover, this is a rare case of an epignathus in which the intracranial lesion was encapsulated and did not invade the brain. These rare but important findings will provide additional, potential therapeutic strategies for gynecologists, neurosurgeons, and pathologists.

     

Defining Extracellular Integrin α-Chain Sites That Affect Cell Adhesion and Adhesion Strengthening without Altering Soluble Ligand Binding

It was previously shown that mutations of integrin α4 chain sites, within putative EF-hand-type divalent cation-binding domains, each caused a marked reduction in α4β1-dependent cell adhesion. Some reports have suggested that α-chain “EF-hand” sites may interact directly with ligands. However, we show here that mutations of three different α4 “EF-hand” sites each had no effect on binding of soluble monovalent or bivalent vascular cell adhesion molecule 1 whether measured indirectly or directly. Furthermore, these mutations had minimal effect on α4β1-dependent cell tethering to vascular cell adhesion molecule 1 under shear. However, EF-hand mutants did show severe impairments in cellular resistance to detachment under shear flow. Thus, mutation of integrin α4 “EF-hand-like” sites may impair 1) static cell adhesion and 2) adhesion strengthening under shear flow by a mechanism that does not involve alterations of initial ligand binding.     

Evidence for the involvement of jasmonic acid in the control of the stem-growth habit of soybean plants

Soybean plants show diversity in stem-growth habit which ranges from the determinate type to the indeterminate type. Stem growth of determinate plants abruptly terminate near the beginning of flowering. The possible involvement of jasmonic acid (JA) in the control of the stem growth-habit was examined in indeterminate and determinate isolines of soybean [ Glycine max (L.) Merril cv. Harosoy]. JA-like activities in leaves of both isolines were very low 20 days before the commencement of flowering. The activity increased rapidly thereafter and reached a maximum near the time of flowering. Although the activities in leaves of both isolines fluctuated in a similar manner, the activity in the determinate isoline was much higher than that in the indeterminate isoline after flowering. The presence of JA in the leaves of the determinate isoline was confirmed by purification by high-performance liquid chromatography and by mass spectrometry. Exogenous application of JA to cultured shoot apices of the indeterminate isoline strongly inhibited growth. These results suggest that jasmonic acid is a major endogenous factor that controls the growth habit of soybean plants.     

Five novel missense mutations of the Lewis gene (FUT3) in African (Xhosa) and Caucasian populations in South Africa

Five novel missense mutations, viz., C304 A, T370 G, G484 A, G667 A, and G808 A, in the Lewis gene (FUT3) were detected in African (Xhosa) and Caucasian individuals in South Africa. These single base substitutions may result in changes in amino acid residues from Gln102 to Lys in the 304 mutation, Ser124 to Ala in the 370 mutation, Asp162 to Asn in the 484 mutation, Gly223 to Arg in the 667 mutation, and Val270 to Met in the 808 mutation. Out of the five novel mutations identified in this investigation, four new alleles (le ^484,667 , le ^484,667,808 , Le ³⁰⁴ , and Le ³⁷⁰ ) were determined in the Xhosa population and two new alleles (le ^202,314,484 and Le ³⁰⁴ ) in the Caucasian population. The determination of α(1,3/1,4)fucosyltransferase activity, after transfection of plasmids containing the new alleles into COS7 cells, suggested that alleles le ^484,667 and le ^484,667,808 encoded an inactive enzyme, and that alleles Le ³⁰⁴ and Le ³⁷⁰ encoded a functional enzyme. In addition, we also examined the incidence of five common alleles, Le ⁵⁹ , le ^59,508 , le ^59,1067 , le ^202,314 , and le ¹⁰⁶⁷ in two populations by the polymerase chain reaction/restriction fragment length polymorphism method and compared differences in the allele frequencies of FUT3 among three ethnic groups (Orientals, Africans, and Caucasians). Received: 19 January 1998 / Accepted: 4 Febraury 1998