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K C Lee

Publications and source records attributed to K C Lee.

At least 145 records · Page 8Linked to original sources
PubMed1998

Phylogenetic analysis of triple gene block viruses based on the TGB 1 homolog gene indicates a convergent evolution.

The complete nucleotide sequence of the triple gene block one (TGB 1) of cymbidium mosaic potexvirus (CymMV) was compared to those from other potex-, carla-, furo- and hordeiviruses. Seven conserved motifs in the TGB 1, including the ATP-GTP binding domain (P-Loop) consensus GXXGKTSTS, were found in all four virus genera. We propose that all TGBV can be classified into phylogenetic clusters based on their TGB 1 homolog genes. These clusters can be further delineated to form subgroups. The first cluster comprises the potexviruses which are further subdivided into three subgroups; BaMV, FMV, PlaMV and PapMV (subgroup Ia); CymMV, PAMV, NMV, SMYEaV and WC1MV (subgroup Ib) and PVX (subgroup Ic). The second cluster comprises carlaviruses with a dual subgrouping; CVB, LSV, PVM, PMV and ASPV (subgroup IIa) and LVX (subgroup IIb). The third cluster carries the most diverse of TGBV comprising furoviruses PCV, PMTV and BSBV (subgroup IIIa) and hordeiviruses PSLV, BSMV and LRSV (subgroup IIIb). The phylogenetic relationships of triple gene block viruses (TGBV) based on the TGB 1 homolog gene indicates a convergent evolution.

Amino Acid Sequence↗
PubMed1998

Do clinical breast examination skills improve during medical school?

PURPOSE: To assess the effects of stage of training, gender, and specialty interest on medical students' breast cancer knowledge, attitudes, and clinical breast examination (CBE) skills as a case study of the progression of physical examination skills during medical education. METHOD: In 1996, questionnaires assessing breast cancer knowledge and attitudes were administered to 493 premedical and first-, second-, and third-year medical students at Northwestern University Medical School. Silicone breast models were used to evaluate the CBE proficiency of a subset of 151 students. RESULTS: Breast cancer knowledge was positively correlated with stage of training (r = .62), with significant differences between all levels (p < .001). In contrast, first-year medical students attained the highest mean lump-detection sensitivity (61.5%), followed by second-year (53.9%) and third-year (43.5%) students (p < .001, first- vs third-year students; p < .10, second- vs third-year students). There was no significant difference in specificity among the four stages. CONCLUSIONS: The results suggest that breast cancer knowledge and attitudes are not related to CBE proficiency, which is a practiced tactile skill. The decline in lump-detection sensitivity with increased stage of training may demonstrate the need for increased attention to palpation skills during the clinical years. These findings are consistent with those of earlier reports that suggest the need for the reinforcement of physical examination skills during clinical education.

Breast Neoplasms↗
PubMed1998

Contemporary presentation and management of a spectrum of mastoid abscesses.

BACKGROUND: The incidence of complications resulting from suppurative otitis media has significantly decreased since the introduction of antibiotics. At the start of the 20th century 50% of all cases of otitis media developed a coalescent mastoiditis. By 1959, the incidence had fallen to 0.4%. Recent studies suggest a current incidence of only 0.24%. Additionally, during the time of Friedrich Bezold (1824-1908), 20% of patients with mastoiditis developed subperiosteal abscess. Interestingly, this has incidence increased; today nearly 50% of patients diagnosed with coalescent mastoiditis have subperiosteal abscess. OBJECTIVE: To review the contemporary presentation, diagnosis, and management of a spectrum of mastoid abscesses. DESIGN: Retrospective case series. SETTING: Hospitals associated with the Department of Otolaryngology/Head and Neck Surgery at the University of California, San Francisco. PATIENTS: Three patients with mastoid abscesses are reported. One patient displayed "classic" Bezold's abscess, with pus escaping the mastoid near the incisura digastrica and tracking along the digastric and sternocleidomastoid muscles into the neck. The second and third patients exhibited temporoparietal swelling secondary to mastoid abscess eroding the root of the zygomatic process, a complication noted by Bezold in 1908 as occurring "in only very rare cases." RESULTS AND CONCLUSIONS: Since only one third of patients show pathologic tympanic membrane changes, and since complaints of otalgia, fever, and tenderness are inconstant, subperiosteal mastoid abscess is frequently a delayed diagnosis. The clinical presentation, pathogenesis, and routes of abscess spread are presented with photographic and radiographic illustration. Medical and surgical management is reviewed, and methods for accurate diagnosis are emphasized.

Abscess↗
PubMed1998

Doxycycline sclerosis of benign lymphoepithelial cysts in patients infected with HIV.

Benign lymphoepithelial cysts (BLCs) are a widely recognized cause of parotid gland swelling in HIV-infected patients. Although they are neither invasive nor associated with malignant degeneration, BLCs can become large and disfiguring. Multiple modalities have been used to control these cysts, but no ideal treatment has been identified. The current study examines the efficacy of doxycycline as a BLC sclerosant in eight patients, and nine BLCs (bilateral BLC in one patient). Follow-up ranged from 12 to 17 months in all cases. Doxycycline sclerosis controlled further cyst growth in 100% of cases with no serious complications. The BLCs became negligible or unnoticeable in two patients, and in six patients (seven BLCs) the cyst became fibrosed and showed no evidence of further growth over the follow-up period. Although further studies are needed to determine the long-term efficacy of this treatment modality, doxycycline sclerosis appears to offer a simple, safe, cost-effective, office-based therapeutic option for the treatment of BLCs in patients infected with HIV.

Adult↗
PubMed1998

Variability of P1 protein of zucchini yellow mosaic virus for strain differentiation and phylogenetic analysis with other potyviruses.

The complete nucleotide sequence of a Singapore isolate of zucchini yellow mosaic potyvirus (ZYMV-S) was determined from viral cDNA clones. The complete genome is 9603 nucleotides in length excluding the poly (A) tail. Computer analysis of the sequence revealed a single large open reading frame (ORF) that presumably encodes a polyprotein of 3082 amino acids with a calculated molecular weight of 350 kDa. Analysis of the helper component (HC) protein showed that the highly conserved motif K-I-T-C which is involved in aphid transmission appeared as K-L-S-C. There is also a change of D-A-G to G-A-G triplet near the N-terminal of the coat protein (CP). Amino acid sequence identity comparison of ZYMV-S gene products with the California and Reunion Island isolates of ZYMV revealed a minimum range of 65-75% to a maximum range of 95-98%. Comparison with other distinct potyviruses showed a low degree of identity from 19-74%. The 5' untranslated region (UTR) of ZYMV-S showed 67% and 72% identity when compared with the California and Reunion Island isolates, respectively. The sequence variability in the 5' UTR of ZYMV can be exploited for strain differentiation and phylogenetic analysis. ZYMV-S shared 94% and 82% identity in the 3' UTR as compared to the California and Reunion Island isolates, respectively. The P1 protein of ZYMV-S shared moderate sequence variability among ZYMV isolates but high sequence variability among all potyviruses. In addition, phylogenetic analysis using the P1 protein indicated that highly variable proteins in the viral genome could also be employed in the study of potyvirus taxonomy and used for strain differentiation.

3' Untranslated Regions↗
PubMed1998

Gastro-intestinal cytomegalovirus infection and extensive colonic ulceration in a renal transplant recipient.

Cytomegalic inclusion disease is a common complication in recipients of organ transplants. In renal transplant recipients, the disease involves the lungs more often than it does the gastrointestinal tract. We report on a recipient of a cadaveric kidney who had cytomegalic inclusion disease that involved both the upper and lower gastro-intestinal tract, and massive gastro-intestinal bleeding that was caused by a large colonic ulcer. Despite treatment with ganciclovir and cytomegalovirus-specific immunoglobulin, the patient died from subsequent complications.

Journal Article↗
PubMed1998

Guidelines for using insulin lispro.

OBJECTIVE: To review the best evidence-based literature on the insulin analogue, lispro insulin, and to provide guidelines for its use. QUALITY OF EVIDENCE: Using the MeSH terms, lispro and insulin analogues, we searched PubMed, Current Contents, MEDLINE, and EMBASE from January 1986 to July 1998 and selected 42 articles out of 97 for high quality and relevance to family medicine. Twenty-eight were randomized controlled trials, but only two studies were blinded because lispro and regular insulin have different optimal times of administration. MAIN MESSAGE: The new insulin analogue, lispro, produces a much more rapid, higher, and shorter-lasting peak level of insulin than regular human insulin, thus mimicking physiologic secretion of insulin more closely. This allows insulin administration just before or just after meals and means patients can manage with fewer snacks. Lispro controls postprandial blood glucose levels better and does not cause hypoglycemia. Although most older studies showed no change in glycosylated hemoglobin (HbA1c) levels, a few recent studies involving refinements, such as continuous subcutaneous insulin infusion or basal insulin to reduce preprandial glucose levels, have found small but significant improvements. Insulin lispro has also been used successfully in cases of insulin resistance and insulin allergy. CONCLUSIONS: Lispro is a useful addition for motivated diabetic patients who like to achieve better control of HbA1c without increased hypoglycemia and to match mealtime insulin injections with diet, exercise, and various lifestyles.

Blood Glucose↗
PubMed1997

Reversed-phase high-performance liquid chromatography of radioiodinated salmon calcitonins.

Reversed-phase HPLC conditions for simultaneous separation of salmon calcitonin, mono- and di-radioiodinated salmon calcitonins and their tryptic digested fragments have been developed. Salmon calcitonin was radioiodinated with Na125I by the iodo-beads method. After solid-phase extraction from the reaction mixtures using C18 Bond Elut cartridges, mono- and di-radioiodinated salmon calcitonins were separated from each other, as well as from unlabeled salmon calcitonin, on a Bondclone 10 C18 column (300x7.8 mm I.D.) by isocratic elution with 0.1% trifluoroacetic acid in 34% aqueous acetonitrile. The characteristics of either iodinated peptides or unlabeled salmon calcitonin were evaluated on the basis of UV absorbance (215 and 280 nm), fluorescence (lambda(ex)=282 nm, lambda(em)=310 nm) and measurement of specific radioactivity by means of a flow-through radio-isotope detector. HPLC separation of a tryptic digest of iodinated salmon calcitonin fraction on a W-porex 5 C18 300 A column (250x4.6 mm I.D.) and subsequent amino acid analysis, led to the conclusion that radioiodination took place at the Tyr residue and not at the His moiety.

Amino Acid Sequence↗
PubMed1997

Mirizzi syndrome caused by xanthogranulomatous cholecystitis: report of a case.

Xanthogranulomatous cholecystitis (XGC) is a rare inflammatory disease of the gallbladder. In severe cases, inflammation extends to adjacent structures, and XGC is sometimes confused with a malignant neoplasm. We recently diagnosed XGC as the preoperative cause of Mirizzi syndrome in a patient based on the clinical course. The patient was admitted because of obstructive jaundice, with gallbladder carcinoma as the suspected cause. The gallbladder was swollen with gallstones and the serum level of carbohydrate antigen 19-9 (CA19-9) was 3070 U/ml at admission. A percutaneous transhepatic cholangiodrainage (PTCD) was done, and the common hepatic duct as well as the right and left hepatic ducts were found to be obstructed. Later, the CA19-9 level and swelling of the gallbladder decreased and the obstruction of the bile ducts disappeared. A cholecystectomy was performed and the intraoperative pathohistological diagnosis of chronic cholecystitis was made from frozen sections. The pathohistological diagnosis of XGC was made from paraffin-embedded sections. Mirizzi syndrome such as that seen in our patient is a rare complication of XGC. XGC occasionally causes extensive inflammation; thus, performing a conventional cholecystectomy can be unsafe. However, in our opinion, a total, not subtotal, cholecystectomy should be done whenever possible because the incidence of gallbladder carcinoma accompanied with XGC is higher than that with ordinary cholecystitis or gallstones.

CA-19-9 Antigen↗
PubMed1997

Hybrid process for the conversion of lignocellulosic materials.

Because of the recalcitrant nature of lignocellulosic materials, it is important to pretreat the biomass in order to obtain a suitable material for the bioconversion. In this study, two different types of pretreatments were performed. The first experiment used a 2-gal Parr reactor operated at 140, 150, 160, and 170 degrees C with sulfuric acid concentrations varying from 0.5 to 2%. A second pretreatment was performed with a two-stage low-temperature process. The first-stage pretreatment was performed at 100 or 120 degrees C with sulfuric acid concentrations of 0.5, 2, and 5% followed by a second-stage pretreatment at 120 degrees C with 2% acid concentration. The best residues for enzymatic hydrolysis and simultaneous saccharification and fermentations (SSF) came from the higher temperature pretreatment with the Parr reactor. However, a large portion of the xylose fraction was degraded to furfural and glucose was degraded to HMF. On the contrary, the two-stage low temperature pretreatment resulted in a very low percentage of xylose degradation, and no glucose degradation. The residues from this two-stage pretreatment performed satisfactorily toward the production of ethanol by SSFs. This study discusses the results obtained from these experiments.

Biomass↗
PubMed1997

Cymbidium mosaic potexvirus RNA: complete nucleotide sequence and phylogenetic analysis.

The complete nucleotide sequence of the genomic RNA of cymbidium mosaic potexvirus (CymMV) was determined to be 6227 nucleotides in length, excluding the poly (A) tail at the 3' terminus. Similar to other potexviruses, its genome organisation is comprised of five major open reading frames (ORFs 1 to 5), encoding a Mr 160 KDa putative RNA-dependent RNA polymerase (RdRp); a Mr 26KDa/13KDa/10KDa triple-gene-block (TGB) and a Mr 24 KDa coat protein. The CymMV encoded proteins shared a high degree of homology to their corresponding proteins of other members of the potexvirus group. The nucleotide sequence of the 5' noncoding region (NCR) of CymMV and all other potexviruses initiates with GAAAA. CymMV possesses the shortest 5' NCR among all potexviruses. Based on phylogenetic comparisons of RdRp and coat protein, CymMV shares a close relationship to PAMV, NMV, WClMV and SMYEaV. This is believed to be the first record of the complete nucleotide sequence of CymMV.

Amino Acid Sequence↗
PubMed1997

Insertion/deletion polymorphism of the angiotensin I-converting enzyme gene in patients with hypertension, non-insulin-dependent diabetes mellitus, and coronary heart disease in Taiwan.

An insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene has been identified that determines most of the plasma ACE activity genetically. Association of the D allele with insulin sensitivity and of the D/D genotype with coronary heart disease (CHD) has been reported in various ethnic populations. To study the role of this genetic polymorphism in patients with hypertension, non-insulin-dependent diabetes mellitus (NIDDM), and NIDDM with CHD in a Taiwanese population, we used a polymerase chain reaction (PCR)-based genotyping technique with an insertion-specific primer for confirmation of the I allele. One hundred ninety-seven unrelated normal controls, 67 subjects with hypertension, 107 subjects with NIDDM, and 70 subjects with NIDDM and CHD were recruited for this study; all were Han Chinese. Subjects without a history of diabetes were studied by a standard 75-g oral glucose tolerance test. Hypertension was diagnosed according to the Fifth Joint National Committee criteria, and CHD was confirmed by a history of acute myocardial infarction and coronary angiographic intervention. The frequency of the I allele of the ACE gene in the normal population was 64.2%, which was higher than reported in white populations. The prevalence of the I allele of the ACE gene was not significantly increased in subjects with hypertension (73.1%), NIDDM (62.1%), and NIDDM with CHD (65%) compared with healthy controls. The I allele of the ACE gene did not correlate with demographic and metabolic variables. I/D polymorphism of the ACE gene is not a marker for hypertension, NIDDM, or CHD in this Taiwanese population.

Age of Onset↗
PubMed1997

An analysis of the natural history of cavernous malformations.

BACKGROUND: The treatment of cavernous malformations has been controversial. Some reports suggest that surgical resection of the lesion for the prevention of recurrent hemorrhage should not be considered because of low hemorrhagic risk. However, the role of surgery in management of cavernous malformations is undergoing reevaluation. The decision for surgical resection should be based on a careful analysis of the natural history of this lesion, which is not well understood. METHODS: We investigated, retrospectively, the natural history of 108 cavernous malformations in 62 patients. Individual cavernous malformations were divided into four categories on the basis of magnetic resonance (MR) findings. The pattern of clinical and radiologic presentation and outcomes of management were analyzed. RESULTS: The age of the patients ranged from 4-63 years (mean: 32.2 years). Multiple lesions were found in 13 of 62 patients (21%) and two of these patients were siblings. Twenty-five out of 62 patients had suffered recurrent symptoms. The bleeding rate was 2.3%/person/year (1.4%/lesion/year) during 2509.6 patient years. There were no significant differences between the bleeding rates of each type of lesion. During the follow-up period of 12-48 months (mean: 22.4 months), two of 28 patients conservatively treated had recurrent hemorrhages (rebleeding rate: 3.8%/person/year). During the follow-up period of 12-66 months (mean: 21.7 months), recurrent hemorrhages were observed in two of 17 patients with radiosurgery (rebleeding rate: 7.8%/person/year). CONCLUSION: Our study has provided a profile of the natural history of these lesions. Based on our results, we recommend surgical excision of cavernous malformations in those patients with recurrent symptoms or acute progressive symptoms.

Adolescent↗