Human immunodeficiency virus type 1(HIV-1) envelope glycoprotein is synthesized as a 160KDa precursor, gp160, that is cleaved by a cellular protease to form the gp120 and gp41 subunits. Mammalian expression vectors were designed that are capabae of efficient expression of various mutant envelope glycoproteins derived from a molecular clone of HIV-1. To construct these vectors, one type of mutation was made at the gp120-gp41 cleavage site by oligonucleotide directed mutagenesis. And another mutation was made to change amino acids in the membrane spanning region of HIV-1 gp41 important for membrane anchorage. Next, these two mutations were combined to generate a vector to have double mutations in cleavage site and membrane spanning region. These mutants were transiently expressed in mammalian cells. The effect of these mutations on envelope glycoprotein synthesis, proteolytic processing and secretion was determined. In addition, cell surface expression and ability of the glycoprotein to induce syncytium formation were examined. This study provides a mammalian expression system that is capable of efficient expression and secretion of soluble gp160.
Amino Acids ; Clone Cells ; Giant Cells ; Glycoproteins* ; HIV* ; HIV-1* ; Humans* ; Membranes ; Mutagenesis, Site-Directed

PURPOSE: Signet-ring cell carcinoma is rather invasive and infiltrative than other histologic types of gastric cancer. We evaluated the characteristic CT findings of signet-ring cell carcinoma especially in the intensity and pattern of contrast enhancement. MATERIALS AND METHODS: We analyzed the CT findings of 22 cases with histologically proven signet-ring cell carcinoma, and compared them with those of 35 cases with histologically proven tubular adenocarcinoma. RESULTS: The double ring enhancement of the gastric mass was seen in 12 cases of signet-ring cell carcinoma and only one case of tubular adenocarcinoma. The masses of signet-ring cell carcinoma were enhanced more by the CT number of 10.2 than those of tubular adenocarcinoma. Of the masses of signet-ring cell carcinoma, those showed double ring enhancement were more intensely enhanced than those showed diffuse enhancement by the CT number of 22.9. CONCLUSION: We thought that neovascularity and different infiltration of the tumor cells in the gastric wall were responsible for the intense enhancement and double ring sign of signet-ring cell carcinoma. The possiblity of signet-ring cell carcinoma is high if a gastric mass show double ring sign and strong contrast enhancement.
Adenocarcinoma ; Carcinoma, Signet Ring Cell* ; Stomach Neoplasms ; Stomach*

Considerable effort has been directed at understanding the structure and function of HIV-1 envelope glycoproteins. It has been difficult to characterize HIV-1 envelope glycoproteins due to the limited availability of these proteins from virus particles or infected cells. To facilitate the structural and functional analysis of HIV-1 envelope glycoproteins, recombinant baculoviruses were generated to express wild type or mutant HIV-1 envelope glycoproteins. The gp160 precursor protein as well as the gp120 glycoprotein were detected in the cell infected with recombinant BacENVw.t containing wild type HIV-1 envelope gene. In the insect cells infected with recombinant BacENVc with mutations at the cleavage site of gp160, a precursor form of envelope glycoprotein was produced, but not secreted into the culture medium. However, the insect cells infected with recombinant BacENVc/t containing both mutations at the cleavage site and membrane spanning region produced mutant envelope glycoproteins that were efficiently secreted into the culture medium in the form of precursor. Therefore the recombinant HIV-1 envelope glycoproteins produced in this system would be useful as immunogens in the development of a vaccine against AIDS.
Baculoviridae* ; Glycoproteins* ; HIV* ; HIV-1* ; Humans* ; Insects ; Membranes ; Staphylococcal Protein A ; Virion

Pituitary adenoma (PA) is a common benign neuroendocrine tumor; however, the incidence and proportion of hormone-producing PAs in Korean patients remain unknown. Authors analyzed 506 surgically resected and pathologically proven pituitary lesions of the Seoul National University Hospital from 2006 to 2011. The lesions were categorized as: PAs (n = 422, 83.4%), Rathke's cleft cysts (RCCs) (n = 54, 10.6%), inflammatory lesions (n = 8, 1.6%), meningiomas (n = 4), craniopharyngiomas (n = 4), granular cell tumors (n = 1), metastatic renal cell carcinomas (n = 2), germinomas (n = 1), ependymomas (n = 1), and unsatisfactory specimens (n = 9, 1.8%). PAs were slightly more prevalent in women (M: F = 1:1.17) with a mean age of 48.8 yr (9-80 yr). Immunohistochemical analysis revealed that prolactin-producing PAs (16.6%) and growth hormone-producing adenomas (9.2%) were the most common functional PAs. Plurihormonal PAs and nonfunctioning (null cell) adenomas were found in 14.9% and 42.4% of patients with PAs, respectively. The recurrence rate of PAs was 11.1%, but nearly 0% for the remaining benign lesions such as RCCs. 25.4% of patients with PAs were treated by gamma-knife after surgery due to residual tumors or regrowth of residual tumor. In conclusion, the pituitary lesions and the proportions of hormone-producing PAs in Korean patients are similar to those of previous reports except nonfunctioning (null cell) PAs, which are unusually frequent.
Adenoma/*pathology ; Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Central Nervous System Cysts/pathology ; Child ; Female ; Growth Hormone/metabolism ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Pituitary Neoplasms/*pathology ; Prolactin/metabolism ; Recurrence ; Sex Factors ; Young Adult

BACKGROUND AND OBJECTIVES: Acoustic parameters of maximal phonation time, sound intensity, fundamental frequency, voice range, jitter and shimmer were analyzed in order to evaluate voice quality and differences among esophageal speech (ES), tracheoesophageal shunt speech (TES), pneumatic aid speech (PA), electrolaryngeal speech (EL) according to phonetic rehabilitation methods in 16 cases of laryngectomees. MATERIALS AND METHODS: We acquired acoustic data on alaryngeal voice by different methods, and analysed each of those using specially designed programs (Laryngeal analyser V1.0 base on Matlab V5.0). RESULTS: Maximal phonation time was significantly longer in TES voice and PA speech than in ES voice (p<0.05). Jitter and shimmer were significantly regular and stable in the EL and PA speech than in the ES and TES voice (p<0.05). Voice range was significantly wider in TES voice and PA speech than in EL and ES voice (p<0.05). In two cases capable of bi-modal speech of ES and TES voice, maximal phonation time was longer with wider voice range in TES voice than in ES voice. Jitter and shimmer were regular and stable in ES voice than in TES voice. CONCLUSION: PA speech displays phonetically more natural laryngeal speech than other rehabilitation methods. But this methods is inconvenient and cosmetically unacceptable, because patients have to bite intraoral vibrator in the patient's mouth. So, we recommend TES voice rather than ES voice, without the use of speech-making device such as EL and PA speech.
Acoustics* ; Humans ; Laryngectomy* ; Mouth ; Phonation ; Rehabilitation* ; Speech, Esophageal ; Voice Quality ; Voice*