Histidine 454 plays an important role in polymerization of human glutamate dehydrogenase

AbstractAlthough previous chemical modification studies have suggested several residues to be involved in the maintenance of the quaternary structure of glutamate dehydrogenase (GDH), there are conflicting views for the polymerization process and no clear evidence has been reported yet. In the present study, cassette mutagenesis at seven putative positions (Lys333, Lys337, Lys344, Lys346, Ser445, Gly446, and His454) was performed using a synthetic human GDH gene to examine the polymerization process. Of the mutations at the seven different sites, only the mutagenesis at His454 results in depolymerization of the hexameric GDH into active trimers as determined by HPLC gel filtration analysis and native gradient polyacrylamide gel electrophoresis. The mutagenesis at His454 has no effects on expression or stability of the protein. The KM values for NADH and 2-oxoglutarate were 1.5-fold and 2.5-fold greater, respectively, for the mutant GDH than for wild-type GDH, indicating that substitution at position 454 had appreciable effects on the affinity of the enzyme for both NADH and 2-oxoglutarate. The Vmax values were similar for wild-type and mutant GDH. The kcat/KM value of the mutant GDH was reduced up to 2.8-fold. The decreased efficiency of the mutant, therefore, results from the increase in KM values for NADH and 2-oxoglutarate. The results with cassette mutagenesis and HPLC gel filtration analysis suggest that His454 is involved in the polymerization process of human GDH

Non-Hodgkin's lymphoma of the sphenoid sinus presenting as isolated oculomotor nerve palsy

BACKGROUND: Solitary involvement of the sphenoid sinus has rarely been reported in non-Hodgkin's lymphoma. Isolated oculomotor nerve palsy is uncommon as an initial presentation of malignant tumors of the sphenoid sinus. CASE PRESENTATION: A 53-year-old woman presented with a three-month history of headache and diplopia. Neurological examination revealed complete left oculomotor nerve palsy. Magnetic Resonance Imaging (MRI) demonstrated a homogenous soft-tissue lesion occupying the left sphenoid sinus and invading the left cavernous sinus. The patient underwent transsphenoidal biopsy and the lesion was histologically diagnosed as non-Hodgkin's lymphoma, diffuse large B-cell type. Tumor cells were positive for CD20 and negative for CD3. Following six cycles of chemotherapy, the left oculomotor nerve palsy that had been previously observed was completely resolved. There was no enhancing lesion noted on follow-up MRI. CONCLUSION: It is important to recognize that non-Hodgkin's lymphoma of the sphenoid sinus can present with isolated oculomotor nerve palsy, although it is extremely rare. The cranial nerve deficits can resolve dramatically after chemotherapy.ope

Full-length cDNA sequences from Rhesus monkey placenta tissue: analysis and utility for comparative mapping

<p>Abstract</p> <p>Background</p> <p>Rhesus monkeys (<it>Macaca mulatta</it>) are widely-used as experimental animals in biomedical research and are closely related to other laboratory macaques, such as cynomolgus monkeys (<it>Macaca </it><it>fascicularis</it>), and to humans, sharing a last common ancestor from about 25 million years ago. Although rhesus monkeys have been studied extensively under field and laboratory conditions, research has been limited by the lack of genetic resources. The present study generated placenta full-length cDNA libraries, characterized the resulting expressed sequence tags, and described their utility for comparative mapping with human RefSeq mRNA transcripts.</p> <p>Results</p> <p>From rhesus monkey placenta full-length cDNA libraries, 2000 full-length cDNA sequences were determined and 1835 rhesus placenta cDNA sequences longer than 100 bp were collected. These sequences were annotated based on homology to human genes. Homology search against human RefSeq mRNAs revealed that our collection included the sequences of 1462 putative rhesus monkey genes. Moreover, we identified 207 genes containing exon alterations in the coding region and the untranslated region of rhesus monkey transcripts, despite the highly conserved structure of the coding regions. Approximately 10% (187) of all full-length cDNA sequences did not represent any public human RefSeq mRNAs. Intriguingly, two rhesus monkey specific exons derived from the transposable elements of AluYRa2 (SINE family) and MER11B (LTR family) were also identified.</p> <p>Conclusion</p> <p>The 1835 rhesus monkey placenta full-length cDNA sequences described here could expand genomic resources and information of rhesus monkeys. This increased genomic information will greatly contribute to the development of evolutionary biology and biomedical research.</p

Microstructure and gas-sensing properties of thick film sensor using nanophase SnO 2 powder

Abstract The object of the present work apply the nanophase SnO 2 powder synthesized by inert gas condensation method (IGC) to thick film hydrogen sensor and to study the effect of microstructural changes of sensors on the sensing properties. SnO 2 gas sensors were printed using nanophase SnO 2 powder without any doping element by a silk screen printing method and subsequently sintered. Among the thick film sensors manufactured at various temperatures, the highest sensitivity was obtained in the sensor sintered at 600 • C, which exhibited its maximum sensitivity of 96% at 250 • C against the hydrogen concentration of 2500 ppm. The results were discussed in viewpoint of the pore structure and the crystallinity of the sensors

Anesthetic management of penetrating neck injury patient with embedded knife -A case report-

Penetrating neck injuries can be a fatal event and they are difficult to manage for both surgeons and anesthesiologists. So, adequate preoperative evaluation is important to improve the patients' outcomes, but this can not be done for hemodynamically unstable or uncooperative patient. Here we present our clinical experience with a patient with a penetrating neck injury and who was hemodynamically stable, but she was uncooperative and the knife was still embedded in her neck. The surgical exploration and bronchoscopic examination were successfully done under monitored anesthesia care

Intron Retention and TE Exonization Events in ZRANB2

The Zinc finger, RAN-binding domain-containing protein 2 (ZRANB2), contains arginine/serine-rich (RS) domains that mediate its function in the regulation of alternative splicing. The ZRANB2 gene contains 2 LINE elements (L3b, Plat L3) between the 9th and 10th exons. We identified the exonization event of a LINE element (Plat L3). Using genomic PCR, RT-PCR amplification, and sequencing of primate DNA and RNA samples, we analyzed the evolutionary features of ZRANB2 transcripts. The results indicated that 2 of the LINE elements were integrated in human and all of the tested primate samples (hominoids: 3 species; Old World monkey: 8 species; New World monkey: 6 species; prosimian: 1 species). Human, rhesus monkey, crab-eating monkey, Africangreen monkey, and marmoset harbor the exon derived from LINE element (Plat L3). RT-PCR amplification revealed the long transcripts and their differential expression patterns. Intriguingly, these long transcripts were abundantly expressed in Old World monkey lineages (rhesus, crab-eating, and African-green monkeys) and were expressed via intron retention (IR). Thus, the ZRANB2 gene produces 3 transcript variants in which the Cterminus varies by transposable elements (TEs) exonization and IR mechanisms. Therefore, ZRANB2 is valuable for investigating the evolutionary mechanisms of TE exonization and IR during primate evolution

Protective and therapeutic effects of an extract mixture of alder tree, labiate herb, milk thistle green bean-rice bran fermentation, and turnip against ethanol-induced toxicity in the rat

An herbal extract mixture and yogurt added to the herbal extract mixture were tested for their protective and therapeutic effects on ethanol-induced liver injury. The herbal extract mixture, yogurt and commercial drugs were used for treatment for two weeks prior to administering a single oral dose of ethanol (3 g/kg body weight). The herbal extract mixture and yogurt added to the herbal extract mixture were found to provide protection against ethanol-induced toxicity comparable to the commercial drug treatment, according to the serum and histopathological analysis. It was also shown that co-treatment with herbal extract mixture and yogurt against a triple oral dose of ethanol (2 g/kg body weight, over one week) provided protection against ethanol toxicity. After the initial set of experiments, the herbal extract mixture and yogurt treatments were extended for three more weeks. When compared to the positive control, further treatment with both the herbal extract and yogurt significantly reduced liver injury and resulted in a lower grade of lipid deposition

Laparoscopic Total Mesorectal Excision in a Rectal Cancer Patient with Situs Inversus Totalis

Situs inversus totalis is a rare anomaly in which the abdominal and thoracic cavity structures are opposite their usual positions. A 41-yr-old woman, who had an ulcerating cancer on the rectum, was found as a case of situs inversus totalis. We present an overview of the operative technique for the first documented laparoscopic total mesorectal excision of a rectal cancer in the patient with situs inversus totalis. Careful consideration of the mirror-image anatomy permitted a safe operation using techniques not otherwise different from those used for the general population. Therefore, curative laparoscopic surgery for rectal cancer in this patient is feasible and safe

Neonatal Erythema Multiforme: A Case Report

Erythema multiforme (EM) is an extremely rare condition in infancy. To the best of our knowledge, there have been only three cases of neonatal EM described in the literature, and no such cases have been reported in Korea. A preterm neonate born at 35 weeks and six days of gestation presented with multiple annular erythematous patches with a targetoid shape over his entire body at 36 days of age (corrected age of 7 days). He had no systemic symptoms except for transient mild fever. No triggering factor except for hepatitis B and BCG vaccination was found. Neutropenia was noted upon laboratory analysis. Skin biopsy specimens showed findings suggestive of erythema multiforme. The skin lesions improved rapidly upon administration of intravenous methylprednisolone; however, neutropenia continued for a much longer period. The significance of neutropenia with respect to the development of EM was not clarified. There has been no recurrence of skin lesions over a one-year follow-up period