Debilitating verruca vulgaris in a patient infected with the human immunodeficiency virus. Dramatic improvement with hyperthermia therapy.
Explore the source record for details and available documents.
AIDS-Related Opportunistic Infections↗
Biomedical subjects
S Kang
Publications and source records attributed to S Kang.
Functional domains of the transcriptional activator NUC-1 in Neurospora crassa.
The NUC-1 regulatory protein directly controls the transcription of these genes and how the activity enzymes in Neurospora crassa. To understand how NUC-1 regulates the transcription of these genes and how the activity of NUC-1 is modulated by other regulatory proteins, two putative functional domains of NUC-1 were analysed: the DNA-binding domain and the regulatory domain. The DNA-binding activity of NUC-1 has not been directly demonstrated; however, results of deletion analysis, sequence analysis of the nuc-1 mutant alleles, and strong sequence similarity with the Saccharomyces cerevisiae PHO4 protein strongly suggest that the basic helix-loop-helix motif of NUC-1 forms a DNA-binding domain. Deletion and mutant analyses revealed that 39 amino acid (aa) residues (aa 463 to 501), or fewer, of NUC-1 are interacting with the negative regulatory factor(s), the PREG and/or PGOV proteins.
Alleles↗
Determination of the rate of cerebral oxygen consumption and regional cerebral blood flow by non-invasive 17O in vivo NMR spectroscopy and magnetic resonance imaging. Part 2. Determination of CMRO2 for the rat by 17O NMR, and CMRO2, rCBF and the partition coefficient for the cat by 17O MRI.
The rate of oxygen consumption (CMRO2) in intact rat and cat brains was calculated by novel data analysis methods from data obtained in in vivo 17O NMR spectroscopy and imaging inhalation studies. Data analysis methods of 17O inhalation measurements are applied to the calculation of CMRO2, regional cerebral blood flow (rCBF), the reflow (R), the arterial venous difference (AVD) and the partition coefficient (lambda). Several of the applied methods for the determination of CMRO2 do not require measurements of regional cerebral blood flow and H2 17O arterial concentration. The proposed methods have been tested, and the results obtained by the different methods are in very good agreement. It is shown that 17O NMR is unique in providing the rate of blood water flow, where the natural abundance 17O NMR signal consists of an internal reference and that lambda is essentially 1. The average values of CMRO2 for rats and cats were found to be 2.09 +/- 0.35 and 1.18 +/- 0.58 (mumol/O2/g tissue)/min, respectively. The average value for rCBF for the cat was found to be 0.38 +/- 0.12 [(mg/g)/min]. The average value for lambda was found to be 1.00 +/- 0.04. The ratio of AVD due to organs other than the brain to AVD due to the brain is smaller than 1 for the rat and the cat. The time and spatial resolution accuracy of the spectroscopic and imaging methods are compared, discussed and statistically analysed. It is concluded that the accuracy of determination of CMRO2 for the rat is higher than for the cat by a factor of 8.
Animals↗
Insertional mutagenesis in Neurospora crassa: cloning and molecular analysis of the preg+ gene controlling the activity of the transcriptional activator NUC-1.
The transcriptional activator NUC-1 controls the transcription of the genes for phosphorus acquisition enzymes, and its activity is regulated by the negative regulatory factors, PREG and PGOV In this report, we describe the cloning and molecular analysis of the preg+ gene. In Neurospora crassa, as in higher eukaryotes, transformation frequently results in nonhomologous integration of transforming DNA. Insertion of transforming DNA into host genes mutates the gene and provides a molecular tag for cloning it. We obtained two mutants that have an insertion in the preg+ and pgov+ genes, respectively, among 2 x 10(5) transformants. The preg+ gene was cloned by screening a Neurospora genomic DNA library with DNA sequences flanking the transforming DNA of the rescued plasmid. Northern analysis showed that the transcription of the preg+ gene is not regulated by phosphate. The carboxy-terminal half of PREG shows strong homology with Saccharomyces cerevisiae PHO80 whose function is analogous to that of PREG. The pregc mutations are located in the well conserved residues which may directly interact with the residues in the regulatory domain of NUC-1.
Alleles↗
Histologic regression in malignant melanoma: an interobserver concordance study.
Histologic evidence for regression as a prognostic indicator in melanoma has shown conflicting results. To assess if melanoma regression is a consistently identifiable histologic feature, an interobserver concordance study was undertaken. Fifty histologic slides of melanoma with Breslow thickness of 1 mm or less were non-randomly selected from the Massachusetts General Hospital Melanoma Registry. The selection was in favor of those with regression present in 44 of 50 slides (88%). Two dermatopathologists working independently evaluated a 2 mm wide bracketed area in each tissue section and then the remainder of the non-bracketed tissue section for regression. Before and after each slide review, the evaluators were required to read criteria for early, intermediate, and late regression explicitly outlined. The overall concordance rate for the presence and absence of regression was 96% (48/50) in the bracketed area and 90% for the outside area. When the group with regression was subdivided into three stages, interobserver agreement fell to 86% for the bracketed, and 66% for the outside area. In at least 30% of cases where regression was detected in the bracketed area, both reviewers observed two or more stages of regression in the remainder of tissue section. Therefore, subdividing the process is impractical and unrealistic. Consistent histologic identification of regression in melanoma requires a simple and systematic approach which should be applied to future studies that include melanoma regression as a prognostic factor.
Humans↗
Differences in the process of earnings determination and inequality between women and men in South Korea.
Explore the source record for details and available documents.
Asia↗
Characterization of the N-linked oligosaccharides in glycoproteins synthesized by microfilariae of Dirofilaria immitis.
In this report, we describe studies on the structures of the N-linked oligosaccharides contained in glycoproteins synthesized by microfilariae of the canine heartworm, Dirofilaria immitis. Microfilariae were incubated in media containing either 2-[3H]mannose, 6-[3H]glucosamine, or 6-[3H]galactose. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorographic analyses indicated that many glycoproteins were radiolabeled by both the mannose and glucosamine, whereas glycoproteins were not radiolabeled by the galactose. Glycopeptides from these total glycoproteins were fractionated and purified by serial lectin affinity chromatography, and the structures of the oligosaccharides in the isolated glycopeptides were analyzed by a variety of techniques. The N-linked oligosaccharides were shown to contain mannose (Man), fucose, N-acetylglucosamine (GlcNAc), and N-acetylgalactosamine (GalNAc). However, they lacked sialic acid and galactose, which are commonly found in mammalian glycoproteins. GalNAc was shown to be in an unusual terminal position and beta-linked in the sequence GalNAc beta GlcNAc beta Man-R, where R is the typical branch of complex-type N-linked oligosaccharides. Similar structures were recently found by us to be synthesized by the helminthic parasite Schistosoma mansoni. These results demonstrate that glycoproteins synthesized by microfilariae of D. immitis have unusual carbohydrate moieties and may lead to a better understanding of the specific roles of glycoprotein oligosaccharides in host-parasite interactions.
Animals↗
Clinical diagnosis of pigmented lesions using digital epiluminescence microscopy. Grading protocol and atlas.
BACKGROUND AND DESIGN: Epiluminescence microscopy (ELM) is a clinical technique that permits in vivo visual inspection of pigmented anatomic structures of the epidermis, dermoepidermal junction, and papillary dermis. A protocol is proposed for systematic visual inspection of pigmented lesions. Seventy pigmented lesions were imaged with a digital ELM camera system. Images were visually inspected for eight "global" ELM features, 23 "local" ELM features, and 18 network features. An atlas of the most clinically significant ELM features is presented with pilot estimates of their sensitivity and specificity for detecting melanoma. RESULTS: Preliminary data suggest that ELM features that may be most specific for melanoma include multicomponent pattern, nodular pattern, pseudopods, radial streaming, blue-gray areas, whitish veil (milky way), and sharp network margins. Epiluminescence microscopic features that may be most sensitive for melanoma include pigment dots, peripheral erythema, peripheral dark network patches, marked mean network irregularity, network line thickness variability, radial streaming, blue-gray areas, and whitish veil (milky way). Epiluminescence microscopic features that may be most sensitive for severe melanocyte atypia include pigment dots, peripheral erythema, hypopigmented network patches, peripheral dark network patches, marked mean network irregularity, and focal absence of network. In addition, features that may have a very high specificity for benign lesions include saccular pattern (suggests hemangioma), globular pattern (suggests a compound or dermal nevus), and multiple comedolike openings (suggests seborrheic keratosis). CONCLUSIONS: Features most sensitive for severe atypia and melanoma could form the basis for a screening test for considering biopsy. Features most specific for melanoma then could be applied to further triage management of pigmented lesions that meet initial screening criteria. In addition, features with very high specificity for benign lesions may help develop ELM criteria to avoid unnecessary surgery.
Atlases as Topic↗
Adrenal steroid receptor activation in rat brain and pituitary following dexamethasone: implications for the dexamethasone suppression test.
The dexamethasone suppression test (DST) has been used extensively to evaluate feedback inhibition of the hypothalamic-pituitary-adrenal (HPA) axis by adrenal steroids. Nevertheless, it remains unclear at what level of the HPA axis and through which adrenal steroid receptor subtype dexamethasone exerts its inhibitory effect. Because adrenal steroid receptor activation is an important prerequisite for dexamethasone to affect cellular function, HPA axis tissues that exhibit evidence of receptor activation following dexamethasone administration are likely site(s) of action for this synthetic hormone to inhibit HPA axis activity. Therefore, type-I and type-II adrenal steroid receptor activation was assessed in the pituitary, hypothalamus, and hippocampus of intact and adrenalectomized rats after overnight exposure to various oral doses of dexamethasone. Results with dexamethasone were compared to similar studies using corticosterone, the endogenous glucocorticoid of the rat. All dexamethasone doses led to significant type-II receptor activation in the pituitary, whereas only an exceedingly high dexamethasone dose activated type-II receptors in the hippocampus and hypothalamus. Dexamethasone had little effect on type I receptors in any tissue at any dose. In contrast, corticosterone significantly activated type-I receptors in all tissues, whereas it activated type-II receptors in the brain and not the pituitary at physiological concentrations. Because dexamethasone activated pituitary type-II receptors at blood concentrations that did not activate type-II receptors in the brain, these results suggest that the DST in humans may primarily be a measure of type-II adrenal steroid receptor feedback inhibition at the level of the pituitary.
Adrenalectomy↗
Central non-Pur.Pyr sequences in oligo(dG.dC) tracts and metal ions influence the formation of intramolecular DNA triplex isomers.
The effect of the central non-Pur.Pyr sequences in oligo(dG.dC) inserts on determining the type of intramolecular DNA triplex isomers formed in negatively supercoiled plasmids was investigated. Different triplex types (H-r3, H-r5, and H-y3), revealed by a combination of chemical probing and Maxam-Gilbert sequencing reactions, were adopted by the oligo(dG.dC) tracts depending on the length and composition of the central non-Pur.Pyr sequences (0, 3, or 5 base pairs) and the kind of metal ions. The H-r3 triplex conformer, one isomer of a Pur.Pur.Pyr structure, was formed in the (C)20 and (C)10GCG(C)10 inserts in plasmids in the presence of certain metal ions. Interestingly, H-r5, the other isomer of the Pur.Pur-Pyr triplex which had not been detected previously, was formed in a (C)9GAATT(C)9 insert in the presence of either Mg2+ or Ca2+. Alternatively, H-y3, one isomer of a Pyr.Pur.Pyr triplex, was formed in the (C)9GAATT(C)9 insert in the absence of metal ions. Thus, central non-Pur.Pyr sequences and metal ions play a role as determinants of the types of intramolecular triplexes formed; they also reduce the requirement of longer Pur.Pyr repeat sequences to form intramolecular triplexes. Furthermore, the effects of MgCl2 concentration and pH on the formation of triplex isomers were examined. The Pur.Pur.Pyr conformations (H-r3 and H-r5) may be the favored conformations in the cellular milieu, since they are stable at physiological pH and metal ion concentration.
Acetaldehyde↗
Multiple primary cutaneous melanomas.
BACKGROUND: Development of multiple primary cutaneous melanomas is a well-recognized phenomenon. As with single primary melanoma, personal and family histories of melanoma and dysplastic nevi (DN) are considered important risk factors. The natural history and impact of regular follow-up evaluation of this entity were examined. METHOD: Through a search of the computerized data bank of the Pathology Department and the Melanoma Registry of the Pigmented Lesion Clinic at Massachusetts General Hospital, 41 patients with multiple cutaneous melanomas were identified. RESULTS: Mean (+/- standard error) age at first diagnosis was 49 +/- 2 years (range, 21-75 years). The male to female ratio was 2:1. The median number of primary melanomas was two (88%). Three patients had three and one had five. Melanoma types included superficial spreading (70%), nodular (8%), lentigo maligna (2%), and unclassified (10%), and in 7% the type was unknown. Nineteen (46%) patients had histologic and/or clinical evidence of DN. For the group with DN, the mean age at first diagnosis (44 +/- 3 years) was significantly less than that of patients without DN (54 +/- 3 years) (P less than 0.05). Family history of melanoma was found in 10 patients (24%). Multiple melanomas were diagnosed concurrently in 16 patients (39%), whereas in 25 (61%) diagnosis was sequential. For the latter group, the mean tumor thickness from the first (1.21 +/- 0.28 mm) to the second melanoma (0.51 +/- 0.08 mm) decreased significantly (P less than 0.05); the median time interval was 36 months (range, 2-372 months). CONCLUSION: These data confirm the need for complete skin examination for patients with newly diagnosed melanoma; and, with subsequent melanomas appearing as long as 31 years after the first melanoma, continued follow-up with complete skin examinations seems prudent.
Adult↗
GC-rich flanking tracts decrease the kinetics of intramolecular DNA triplex formation.
The effect of the base composition of flanking sequences on DNA intramolecular triplex formation was investigated in negatively supercoiled plasmids. The rates of triplex formation at two oligopurine.oligopyrimidine inserts with interrupting sequences in plasmids containing AT- or GC-rich flanking sequences were compared as a function of temperature, pH, and negative superhelical density. The kinetics of the transition of linear B-DNA to triplex (also called H-DNA) were influenced by all of these factors; triplexes were formed slower in a GC-rich background than in an AT-rich background. However, at equilibrium, the same amounts of the triplexes in AT- or GC-rich contexts were formed, and the conformations adopted by (GAA)4TTCGC(GAA)4 showed the canonical intramolecular triplex as mapped with chemical probes. We propose that the GC-rich segments caused this effect by thermodynamically clamping the DNA inserts, since the dependence of kinetics on base composition disappeared in tetraalkylammonium ions which eliminate the dependence of helix-coil transitions on base composition. The dependence of the kinetics of intramolecular triplex formation on flanking sequences further strengthens the concept of the role of DNA as a dynamic participant in cellular events.
Base Sequence↗
Lymphotropic papovavirus transforms hamster cells without altering the amount or stability of p53.
Expression of the early regions of several primate polyomaviruses (SV40, BKV, JCV, and LPV) in hamster cells induces transformation, manifested by the ability to grow in soft agar. Hamster cells transformed by SV40 contain complexes between the SV40 T antigen and the cellular tumor suppressor protein p53. We detected analogous complexes between p53 and the BKV T antigen in hamster cells transformed by the BKV early region, where the half life of p53 increased 16-fold. However, neither a LPV-transformed hamster fibroblast cell line [LPV-HE (F); K. K. Takemoto and T. Kanda, 1984, J. Virol. 50, 100-105] nor BHK-21 cells transformed by the LPV early region contained detectable complexes between the LPV T antigen and p53, nor was the stability of p53 in LPV transformed BHK-21 cells altered. Association between hamster p53 and the LPV T antigen expressed as glutathione S-transferase fusion protein could not be detected in vitro. These data indicate that alteration of the amount or stability of p53 is not required for transformation of hamster cells by LPV. However, as viruses such as SV40 and BKV whose T antigens bind p53 are oncogenic in hamsters, whereas LPV is not, the alteration of p53 amount or stability may be required for tumorigenesis.
Agar↗
Determination of the rate of cerebral oxygen consumption and regional cerebral blood flow by non-invasive 17O in vivo NMR spectroscopy and magnetic resonance imaging: Part 1. Theory and data analysis methods.
Theory and novel data analysis methods of 17O inhalation measurements are presented for the calculation of CMRO2, regional cerebral blood flow (rCBF), the reflow (R), the arterial venous difference (AVD) and the partition coefficient (lambda). Several of the methods proposed for the determination of CMRO2 do not require measurements of regional cerebral blood flow and H2(17)O arterial concentration. All methods of analysis are based on the Kety-Schmidt approach.
Animals↗
[Chemical constituents of Rhodiola kirilowii (Reg.) Reg].
Three compounds were isolated from the water-soluble part of alcohol extracts of rhizomes of Rhodiola kirilowii. Two of them were identified as salidroside and tyrosol, respectively by chemical and spectral analysis. beta-sitosterol was obtained from the petroleum extracts of the plant.
Drugs, Chinese Herbal↗
[Isolation and identification of julibrotriterpennoidal lactone A from Albizia julibrissin Durazz].
Julibrotriterpennoidal lactone A was isolated from the cortex of Albizia julibrissin. Its structure (the C28----C21 lactone of, 3 beta, 16 beta, 21 beta-trihydroxy-delta 12-oleanen-28-oic acid) has been determined on the basis of spectral evidence (IR, 1HNMR, 13C NMR and MS).
Abortifacient Agents, Nonsteroidal↗
Primary malignant melanoma of the external auditory canal: a case report with presentation as an aural polyp.
A case of primary cutaneous melanoma of the external auditory canal and a review of the literature are reported. This is the first reported case with microstaging of the tumor. The tumor presented as a polypoid obstructive lesion of the external ear canal. Although occurrence of melanoma in this location is extremely rare, differential diagnosis of an external ear canal polyp should be expanded to include primary malignant melanoma.
Biopsy↗
Prognosis after initial recurrence of cutaneous melanoma.
We reviewed 231 patients who developed recurrent disease 1 to 218 months after surgical therapy for clinical stage I cutaneous melanoma. Metastatic lesions amenable to surgery, including visceral recurrences, were resected. Adjuvant systemic chemotherapy/immunotherapy or regional hyperthermic perfusion was added in patients with unresected disease. Local irradiation was employed for nonresectable brain or other isolated symptomatic metastases. The overall 5-year survival rate after initial recurrence was 36%. In patients with soft tissue or nodal recurrence, the 5-year survival rates were 49% and 38%, respectively; six (11%) of 53 patients whose initial recurrence was in a visceral organ achieved prolonged remission. Primary lesion anatomic site, thickness, pathologic type, and interval from initial therapy to recurrence were unrelated to survival. Significant prognostic factors included the site of initial metastasis, stage of primary disease, and the successful complete eradication of gross disease by surgical excision or intensive chemotherapy.
Adult↗