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G Gong

Publications and source records attributed to G Gong.

At least 55 records · Page 3Linked to original sources
PubMed1999

Oxygen delivery does not limit cardiac performance during high work states.

This study tested the hypothesis that the loss of myocardial high-energy phosphates (HEP), which occurs during high cardiac work states [J. Zhang, D. J. Duncker, Y. Xu, Y. Zhang, G. Path, H. Merkle, K. Hendrich, A. H. L. From, R. Bache, and K. Uğurbil. Am. J. Physiol. 268: (Heart Circ. Physiol. 37): H1891-H1905, 1995], is not the result of insufficient intracellular O(2) availability. To evaluate the state of myocardial oxygenation, the proximal histidine signal of deoxymyoglobin (Mb-delta) was determined with (1)H nuclear magnetic resonance spectroscopy (MRS), whereas HEP were examined with (31)P MRS. Normal dogs (n = 11) were studied under basal conditions and during combined infusion of dobutamine and dopamine (20 micrograms . kg(-1). min(-1) iv each), which increased rate-pressure products to >50,000 mmHg. beats. min(-1). Creatine phosphate (CP) was expressed as CP/ATP, and myocardial myoglobin desaturation was normalized to the Mb-delta resonance present during total coronary artery occlusion. This Mb-delta resonance appeared at 71 parts per million downfield from the water resonance. CP/ATP decreased from 2. 22 +/- 0.12 during the basal state to 1.83 +/- 0.09 during the high work state (P < 0.01), whereas DeltaP(i)/CP increased from 0 to 0.21 +/- 0.04 (P < 0.01). Despite these HEP changes, Mb-delta remained undetectable. In contrast, when a coronary stenosis was applied to produce a similar decrease in CP/ATP, Mb-delta reached 0.38 +/- 0.10 of the value present during total coronary occlusion. These data demonstrate that Mb-delta is readily detected in vivo during limitation of coronary blood flow sufficient to cause a decrease of myocardial CP/ATP. However, similar HEP changes that occur at high work states in the absence of coronary occlusion are not associated with a detectable Mb-delta resonance. The findings support the hypothesis that the myocardial HEP changes observed at high work states are not due to inadequate O(2) availability to the mitochondria and emphasize the limitations of interpreting HEP alterations in the absence of knowing the level of myocyte oxygenation.

Animals↗
PubMed1999

Extramammary Paget's disease with aggressive behavior: a report of two cases.

Extramammary Paget's disease (EMPD) is an intraepithelial neoplastic disorder which is included as a rare malignant condition. However, it sometimes shows aggressive behavior of local recurrence and coexisting malignancy. We had experienced nine cases of EMPD involving the scrotum for seven years. Two cases of them presented metastasis. The first case presented extensive inguinal lymph node metastasis with underlying adnexal adenocarcinoma one year after wide local excision. The second case initially presented multiple metastasis to the liver and in the lymph node. The latter, showing fulminant progression with liver metastasis, may be only the second case reported in English literature. EMPD is considered as a malignant neoplasm with aggressive behavior from initial presentation. Because wide local excision of the lesion alone may be occasionally insufficient, a careful follow-up must be done to detect recurrence or internal malignancy.

Aged↗
PubMed1999

Sclerosing Mucoepidermoid carcinoma with eosinophilia of the thyroid glands: a case report with clinical manifestation of recurrent neck mass.

Sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) is a recently recognized malignant neoplasm of the thyroid gland. About 14 cases of SMECE have been reported and this is the first reported case in Korea. A 57-year-old woman presented with right neck mass for 20 years. Total thyroidectomy was performed under the impression of thyroid carcinoma. The resected thyroid gland showed a poorly circumscribed hard mass. Histologically, the tumor consisted of solid nests of large atypical cells with dense fibrous stroma. The tumor cells showed squamoid appearance with abundant eosinophilic cytoplasm. There were also rare mucin-containing cells within the nests. Within the hyalinized stroma, numerous eosinophils were found. The surrounding thyroid parenchyma displayed Hashimoto's thyroiditis. There was metastasis in a regional lymph node. Two years after initial surgery, she underwent a modified radical neck dissection due to recurrent neck mass. After the radiation therapy for eight weeks, laryngectomy and esophagectomy were performed due to a recurrent carcinoma in the esophageal wall. We report an additional case of SMECE, with metastasis to regional lymph nodes and esophagus. The tumor appears to be more aggressive than previously reported and a correct diagnosis can be rendered by just examining the metastatic lesions.

Carcinoma, Mucoepidermoid↗
PubMed1999

Flow cytometric immunophenotyping in fine-needle aspiration of lymph nodes.

Fine-needle aspiration (FNA) of lymph nodes has been regarded as a useful method in the diagnosis of lymphadenopathy. However, this procedure has been shown to be of limited value in the diagnosis of low or intermediate grade malignant lymphomas in some studies. Immunophenotyping is an essential adjunct to cytomorphology for the diagnosis of lymphoma by FNA. Immunophenotyping using flow cytometry (FCM) is rapid, objective and reliable. Using FCM, multiparametric analysis of 33 FNA materials from lymph nodes was performed and profiles of surface markers of lymphoid cells were assessed. In reactive hyperplasia, patterns of cell surface markers were quite variable, but disclosed polyclonality. Most of the B-cell lymphomas showed immunophenotypes for B-cell lineages with their kappa: lambda or lambda: kappa ratio being over 3:1. In T-cell lymphomas, T-cell surface markers were predominantly expressed as well. In conclusion, our results suggest that immunophenotyping of lymph node aspirates is a valuable diagnostic adjunct for lymphoproliferative disorders, particularly in B-cell lymphomas because immunophenotyping can be easily and adequately performed by FCM.

Antigens, CD19↗
PubMed1999

[Pathogenicity in mice infected with three different strains H. pylori].

OBJECTIVE: To observe the differences of colonization and histopathology between CagA+ strains and lacking CagA by three different strains infecting C57BL/C mice. METHODS: CYP3401 wild type strain (CagA+), CYP3401(the isogenic CagA) knockout mutant CagA-, Sydney strain (CagA+) were used. The mice were administered orally with 0.5 ml, 10(9) CFU/ml of the above bacterial suspensions, respectively. Serum IgG antibodies were measured by ELISA. All the mice were sacrificed at 8 weeks after inoculation and their stomaches were removed for histopathologic study. RESULTS: The colonization of the bacteria was evident in Sydney strain and mild type strain, but characterized by wild to moderate infiltration by nutrophils and momocytes histologically. Only a small number of organisms were observed in the CagA- strains group. The levels of serum IgG antibodies were the highest in Sydney and wild strains group as compared with the control group (P < 0.01). There was no significant difference between the CagA-group and the control group. CONCLUSION: A strong correlation was observed between CagA+, bacterial colonization, gastric mucosa inflammation, and serum IgG antibodies. The study of C57BL/C mice helps understand the pathogenicity with CagA+ strains in human body and study H. pylori infection and associated diseases.

Animals↗
PubMed1999

[Fluorescence quenching method for the determination of trace zirconium with 5'-nitor-salicylfluorone and hexadecyltrimethylammonium bromide].

A new fluorometric method has been developed for the determination of trace zirconium, based on the fluorescence quenching effect of Zr (IV)-5'-nitro-salicylfluorone (5'-N-SAF)-hexadecyltrimethylammonium bromide (CTMAB). In the H2SO4 medium and in the presence of CTMAB Zr (IV) reacts on 5'-N-SAF to form a 14 orange complex. Its maximum excitation wavelengths are 475 and 505 nm,and the maximum emission wavelength is 525 nm. The linear range is 2.0-80 microg/L, and the detection limit is 2.0 microg/L. The method has been applied to the direct determination of trace Zr (IV) in the aluminium alloy reference sample with satisfactory results.

English Abstract↗
PubMed1998

Change of bone mass in postmenopausal Caucasian women with and without hormone replacement therapy is associated with vitamin D receptor and estrogen receptor genotypes.

Our purpose is to assess whether genotypes of the vitamin D receptor (VDR) and estrogen receptor (ER) and their interaction influence changes in bone mass in postmenopausal Caucasian women with and without hormone replacement therapy (HRT). A population of 108 US Mid-West women who participated in a study of low-dose continuous estrogen/progestin was genotyped at the VDR BsmI site and the ER XbaI and PvuII sites. Adequate vitamin D and calcium nutritional intakes were assured in all the study subjects. For the 3.5-year duration of the study, we analyzed changes in bone mineral density (BMD) at the spine, femoral neck, distal radius, and the total body (total body bone mineral content, tbBMC). We adjusted for confounding factors, such as age and weight, in the analysis. We found that VDR and/or ER genotypes and/or their interaction generally had significant effects on the changes in the bone mass measurements in both the placebo and HRT groups. When a significant gene-by-gene interaction exists between VDR and ER genotypes, failure to account for them in analyses may yield nonsignificant results, even if significant genotypic effects exist. The amount of variation in changes in bone mass measurements explained by the total genotypic effects of the VDR and ER loci varies from approximately 1.0% (for the tbBMC changes in combined placebo and HRT groups) to approximately 18.7% (for the spine BMD changes in the HRT group). These results suggest that individual genotypes are important factors in determining changes in bone mass in the elderly with and without HRT and thus may need to be considered with respect to the treatment to preserve bone mass in elderly Caucasian women.

Aged↗
PubMed1998

Kaposi's sarcoma-associated herpesvirus in Kikuchi's disease.

Kikuchi's disease is a fairly common self-limited disorder among Orientals that usually involves the cervical lymph nodes of young individuals and occurs predominantly in females. Frequently, the disease is associated with fever or flu-like symptoms, an elevated erythrocyte sedimentation rate (ESR), neutropenia, and lymphocytosis with atypical lymphocytes in the peripheral blood, suggesting a viral origin. However, no infectious agent has been identified. The presence of Kaposi sarcoma-associated herpesvirus, known as human herpesvirus 8 (KSHV/HHV 8), was investigated by polymerase chain reaction (PCR) in archival tissue from 26 cases of Kikuchi's disease using published sequences of KSHV/HHV 8 as primers. PCR products were further characterized by Southern blot analysis. Forty reactive lymph nodes and a case of Kaposi sarcoma (KS) were included as negative and positive controls, respectively. Patients consisted of 10 men and 16 women with a mean age of 27 years. All patients were previously healthy and presented with cervical or axillary lymphadenopathy. None were positive for human immunodeficiency virus (HIV) or otherwise immunocompromised. Viral DNA was amplified by PCR in six cases of Kikuchi's disease (23%) and the control KS tissue. Southern blot analysis confirmed that the amplified products were KSHV/HHV 8. In the reactive lymph nodes, no viral genome was amplified by PCR. The presence of DNA sequences of KSHV/HHV 8 in a substantial portion of Kikuchi's disease suggests that KSHV/HHV 8 might play an important role in the pathogenesis of a subset of Kikuchi's disease.

Adolescent↗
PubMed1998

Prevalences of Gs alpha, ras, p53 mutations and ret/PTC rearrangement in differentiated thyroid tumours in a Korean population.

OBJECTIVE: In thyroid tumours, ras, Gs alpha, p53 mutations and ret/PTC rearrangement have been reported with variable prevalences in different geographical regions. We studied the prevalence of these mutations and rearrangement in thyroid tumours in a Korean population. As MDM2 and Bcl-1 protein expressions have been suggested to be associated with p53 protein, we also studied possible relationships among them. PATIENTS AND DESIGN: Eleven cases of adenomatous goitre, eight cases of follicular adenoma, five cases of follicular carcinoma and 37 cases of papillary carcinoma were included in this study. To find mutations and rearrangement, RT-PCR, SSCP and/or direct sequencing, after subcloning if necessary, were used, and immunohistochemical stainings were performed for p53, MDM2 and Bcl-2 proteins in cases of papillary carcinoma. RESULTS: We could not find any rearrangement for ret/PTC-1, -2, -3 and mutation of Gs alpha. For the ras oncogene, K and H-ras mutations were not found, but N-ras mutations, point mutation of CAA to CGA in codon 61, were detected in one follicular adenoma (12.5%, 1/8) and one follicular carcinoma (33%, 1/3). p53 mutations were detected in only one case of papillary carcinoma (3%, 1/31: exon 8, codon 266 GGA-->GAA). In 30 cases of papillary carcinoma without p53 mutation, the prevalences of positive immunohistochemical staining were 13.3% for p53 protein, 53.3% for MDM2 protein and 56.7% for Bcl-2 protein. While over-expression of p53 protein was not significantly related to that of MDM2 and Bcl-2 proteins, over-expression of MDM2 and Bcl-2 in papillary carcinoma were associated. CONCLUSION: ret/PTC rearrangement, Gs alpha, ras and p53 mutations are relatively rare in differentiated thyroid neoplasms from a Korean population, which may reflect genetic and environmental differences from patients in countries with high prevalences. P53 protein over-expression was noted in 13.3% of papillary carcinoma cases without p53 mutation and was not significantly related to MDM2 and Bcl-2 expression.

Adenoma↗
PubMed1998

A study of the viral etiology of histiocytic necrotizing lymphadenitis (Kikuchi-Fujimoto disease).

Histiocytic necrotizing lymphadenitis (HNL) or Kikuchi's disease is a distinctive, self-limited disorder characterized by necrotizing cervical lymphadenopathy in young individuals. HNL is more prevalent among Asians and is a relatively common disorder among Koreans. A preceding fever, lymphopenia, and occasional skin rashes suggest a viral etiology and there have been sporadic reports of viral association. However, so far, no infectious agent has been proven to be etiologically related. In the present study, the authors examined HNL tissue samples for the presence of the genome of herpesviridae. A polymerase chain reaction was performed on 12 freshly frozen lymph nodes with HNL with a single pair of consensus primers selected within a highly conserved region of the DNA polymerase gene of the Epstein-Barr virus (EBV), designed to detect herpes simplex type 1 (HSV1), herpes simplex virus type 2 (HSV2), and cytomegalovirus (CMV) in addition to EBV. The amplified products of known sizes were then analyzed by a single restriction enzyme treatment for confirmation. No viral DNA was amplified in any of the 12 cases of histiocytic necrotizing lymphadenitis. The authors conclude that there is no evidence that HSV1, HSV2, CMV, or EBV plays any role in the pathogenesis of histiocytic necrotizing lymphadenitis.

Adolescent↗
PubMed1998

Usual interstitial pneumonia: relationship between disease activity and the progression of honeycombing at thin-section computed tomography.

The authors estimate the relationship between the progression of honeycombing and disease activity of usual interstitial pneumonia (UIP) by open lung biopsy specimen and ground-glass opacity on thin-section computed tomography (CT). Open lung biopsy specimens and the initial and follow-up thin-section CT of 29 patients with proven UIP are reviewed. Follow-up thin-section CTs were performed from 2 to 61 months (mean, 15.3 months) after biopsy. The interval between the initial CT and open lung biopsy was from 2 to 30 days (mean, 10.0 days). Areas of ground-glass opacity and honeycombing were quantified respectively on each CT slice by using a 0%-100% scale with 10% increments. Each open lung biopsy specimen was scored semiquantitatively for alveolar desquamation, alveolar septal inflammation, inflammatory airway narrowing, obstructive pneumonitis, and lymphoid nodules. Patients were classified into either a mild or severe activity group according to the median value of the pathologic score and the median value of the area of ground-glass opacity. The authors compared the progression of honeycombing on follow-up thin-section CT between the groups. The progression of honeycombing in UIP was significantly faster in the severe activity group than in the mild group according to the pathologic score (p = 0.003) and the area of ground-glass opacity (p = 0.0024). In patients with UIP, more active inflammation of the pulmonary interstitium results in faster progression of honeycombing in long-term follow-up.

Adult↗
PubMed1997

Bone dimensional change with age: interactions of genetic, hormonal, and body size variables.

Changes in bony dimensions with age were assessed longitudinally from standardized X-ray films in 170 middle-aged Caucasian women, starting at age 40 years and with a median duration of observation of 21.125 years. Consistent with earlier work, cortical area of the metacarpals and radial shaft declined with age at rates ranging from 0.57 to 0.86%/year. As predicted, estrogen replacement therapy decreased this loss in a dose-dependent manner. Not previously reported is the fact that weight gain over the period of observation reduced upper extremity bone loss. Moreover, this protection was independent of the estrogen effect. In contrast with bone loss in the upper extremity, both femur shaft diameter and femur shaft cortical area increased significantly with age (0.23 and 0.26%/year, respectively). Estrogen replacement therapy inhibited femur shaft expansion but had no effect on femur cortical area. Weight change, however, strongly influenced gain (or loss) of femur cortical area: those in the highest weight change tertile gained 4 times as much cortical area as those in the lowest weight change tertile. VDR genotype also significantly influenced femoral shaft changes: women with the bb genotype had both greater shaft expansion and a greater increase in cortical area. The VDR effects were independent of the effects of weight change and estrogen. Femoral shaft expansion was of sufficient magnitude to suggest that the mechanical properties of the entire femur may change appreciably with age. Finally, contrary to widespread belief, there was significant, if modest, expansion at the femoral neck with age.

Adult↗
PubMed1997

The value of pancreatoscopy in patients with mucinous ductal ectasia.

We report here on three cases of mucinous ductal ectasia in which the diagnosis was suggested by abdominal computed tomography and finally established by duodenoscopy with pancreatoscopy. Duodenoscopic examination of the ampulla of Vater demonstrated a patulous papillary orifice and extrusion of viscid mucus. Pancreatoscopic examination was carried out in all three patients, and characteristic findings such as papillary or villous mucosal projections coated with whitish gelatinous mucus were noted. In patients with mucinous ductal ectasia in whom the radiographic findings are equivocal, pancreatoscopic examination may provide valuable information for the differential diagnosis of amorphous filling defects in the main pancreatic duct, and may provide information that helps to determine the extent of the pathology and the resection margin.

Adenocarcinoma, Mucinous↗
PubMed1997

Linkage of a gene causing high bone mass to human chromosome 11 (11q12-13)

The purpose of this paper is to report the linkage of a genetic locus (designated "HBM") in the human genome to a phenotype of very high spinal bone density, using a single extended pedigree. We measured spinal bone-mineral density, spinal Z(BMD), and collected blood from 22 members of this kindred. DNA was genotyped on an Applied Biosystems model 377 (ABI PRISM Linkage Mapping Sets; Perkin Elmer Applied Biosystems), by use of fluorescence-based marker sets that included 345 markers. Both two-point and multipoint linkage analyses were performed, by use of affected/unaffected and quantitative-trait models. Spinal Z(BMD) for affected individuals (N = 12) of the kindred was 5.54 +/- 1.40; and for unaffected individuals (N = 16) it was 0.41 +/- 0.81. The trait was present in affected individuals 18-86 years of age, suggesting that HBM influences peak bone mass. The only region of linkage was to a series of markers on chromosome 11 (11q12-13). The highest LOD score (5.21) obtained in two-point analysis, when a quantitative-trait model was used, was at D11S987. Multipoint analysis using a quantitative-trait model confirmed the linkage, with a LOD score of 5.74 near marker D11S987. HBM demonstrates the utility of spinal Z(BMD) as a quantitative bone phenotype that can be used for linkage analysis. Osteoporosis pseudoglioma syndrome also has been mapped to this region of chromosome 11. Identification of the causal gene for both traits will be required for determination of whether a single gene with different alleles that determine a wide range of peak bone densities exists in this region.

Absorptiometry, Photon↗
PubMed1997

cGMP level that reduces cardiac myocyte O2 consumption is altered in renal hypertension.

We tested the hypothesis that cardiac myocytes from hypertensive (one kidney, one clip; 1K,1C) cardiac-hypertrophied rabbits require higher guanosine 3',5'-cyclic monophosphate (cGMP) to similarly lower O2 consumption than control myocytes and that this effect is caused by differences in guanylate cyclase activity. Using isolated myocytes from control and 1K,1C New Zealand White rabbits, we obtained O2 consumption (nl O2 x min(-1) x 10(5) cells) and cGMP (fmol/10(5) cells) levels after stimulation of guanylate cyclase with nitroprusside, CO, or guanylin (10(-8)-10(-5) M). Soluble guanylate cyclase activity was also determined. Basal cGMP was elevated in 1K,1C vs. control (176 +/- 28 vs. 85 +/- 13) myocytes. cGMP increased in 1K,1C and control myocytes after stimulation with nitroprusside, CO, and guanylin. Guanylate cyclase activity in 1K,1C vs. control myocytes was not statistically different. Basal O2 consumption in 1K,1C vs. control myocytes was comparable (307 +/- 1 vs. 299 +/- 22). O2 consumption was similarly decreased when guanylate cyclase was stimulated. Control regression equations correlating cGMP and O2 consumption were O2 consumption = -1.46 x [cGMP] + 444.65 (r = 0.96) for CO, O2 consumption = -0.58 x [cGMP] + 328.48 (r = 0.82) for nitroprusside, and O2 consumption = -1.25 x [cGMP] + 389.15 (r = 0.88) for guanylin. The 1K,1C regression equations were O2 consumption = -1.36 x [cGMP] + 537.81 (r = 0.97) for CO, O2 consumption = -0.23 x [cGMP] + 307.30 (r = 0.88) for nitroprusside, and O2 consumption = -1.27 x [cGMP] + 502.91 (r = 0.89) for guanylin. These data indicate that 1K,1C hypertrophic myocytes had higher cGMP than controls at every level of O2 consumption. This effect was not caused by differences in basal or maximal guanylate cyclase activity.

Animals↗
PubMed1997

Gastrointestinal involvement in Henoch-Schönlein syndrome: CT findings.

OBJECTIVE: The purpose of this study was to describe the CT features of gastrointestinal involvement in seven patients with Henoch-Schönlein syndrome. CONCLUSION: Although the incidence of Henoch-Schönlein syndrome is low, it should be considered when CT scans show multifocal areas of bowel-wall thickening, mesenteric edema, vascular engorgement, and nonspecific lymphadenopathy. It should be considered especially in young patients with acute gastrointestinal symptoms.

Adolescent↗
PubMed1997

[Features of nine strains of thermophilic methanogens].

Nine strains of thermophilic bacteria producing methane from hydrogen and carbon dioxide or formate were isolated and purified from four samples of anaerobic digester feeding with family waste water. They are similar with each other on cell morphology and physiological characteristics. The cells are straight or slightly curved with rounded ends, 0.3-0.4 x 1-3 microns; single or in pairs, sometimes joined into long chains (> 10 microns); Gram-positive, non-mo-tile, non-spore-forming. The organisms under fluorescence microscope shine green fluorescence specific for methanogens and are chemoautotrophs. The temperature range for growth is 30-75 degrees C, optimum 55-65 degrees C. The initial pH range for growth is 5.8-9.0, optimum 6.9-7.6. The G + C content of DNA of the strain 602B3 is 44.6 mol%. According to the results of identification, the strain 602B3 is considered of belonging to species Methanobacterium thermoformicicum 602B3.

Methane↗