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Lai KN, Lai FM, King WW, Li PK, Siu D, Leung CB, Lui SF. Dermatofibrosarcoma protuberans in a renal transplant patient. THE AUSTRALIAN AND NEW ZEALAND JOURNAL OF SURGERY 1995; 65:900-2. [PMID: 8611119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Dermatofibrosarcoma protuberans in an unusual soft tissue tumour with a propensity for local recurrence and rarely metastatic spread. Given its indolent course it may be mistaken for atypical scarring or a keloid growth. Early diagnosis and prompt wide local resection of this entity are required in order to prevent a local recurrence. We report a patient who developed locally invasive dermatofibrosarcoma protuberans 4 years after a successful renal transplantation. Although other forms of sarcoma have been reported as a complication of organ transplantation and immunosuppression, this pathology has, so far, not been reported in a transplant recipient.
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Li PK, Mak TW, Chan TH, Wang A, Lam CW, Lai KN. Effect of fluvastatin on lipoprotein profiles in treating renal transplant recipients with dyslipoproteinemia. Transplantation 1995; 60:652-6. [PMID: 7570971 DOI: 10.1097/00007890-199510150-00006] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A single, blinded placebo-drug trial was conducted to study the efficacy and safety of fluvastatin, a new 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor, in treating dyslipoproteinemia in 16 renal transplant recipients who had been on an immunosuppressive regimen that included cyclosporine (CsA). They were studied for 32 consecutive weeks, with 4 weeks of baseline treatment, 4 weeks of placebo, 12 weeks of treatment with fluvastatin 20 mg daily, and 12 weeks of fluvastatin 40 mg daily. Blood samples were obtained every 4 weeks for measurement of the lipoprotein profiles, which included total cholesterol (TC), triglyceride, low density lipoprotein (LDL)-, high density lipoprotein (HDL)-, HDL2-, HDL3- and very low density lipoprotein-cholesterol (C), apolipoprotein (Apo) A-1, Apo B, and lipoprotein(a). Fifteen patients completed the trial. After 12 weeks of treatment, fluvastatin 20 mg significantly reduced TC by 13.4% (from 6.7 +/- 0.5 [mean +/- SEM] to 5.8 +/- 0.2 mmol/L), LDL-C by 22% (from 4.1 +/- 0.3 to 3.2 +/- 0.2 mmol/L), and Apo B by 13.2% (from 159.6 +/- 8.8 to 138.6 +/- 9.2 mg/dl) (P < 0.005). The subsequent 12-week treatment of fluvastatin 40 mg significantly reduced TC by 16.4% to 5.6 +/- 0.3 mmol/L, LDL-C by 29.3% to 2.9 +/- 0.2 mmol/L, and Apo B by 18.2% to 130.6 +/- 5.5 mg/dl (P < 0.00005). There was no significant change in levels of other lipoproteins, including lipoprotein (a). There were no significant changes in the whole blood trough CsA concentrations, renal and liver function tests, and serum creatine phosphokinase level during treatment when compared with baseline and placebo. No patient complained of myalgia or failed to complete the study due to side effects of the drug. Fluvastatin appears to be safe and effective in treating dyslipoproteinemia in renal transplant recipients who are maintained on CsA.
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Li PK, Rhodes ME, Jagannathan S, Johnson DA. Reversal of scopolamine induced amnesia in rats by the steroid sulfatase inhibitor estrone-3-O-sulfamate. BRAIN RESEARCH. COGNITIVE BRAIN RESEARCH 1995; 2:251-4. [PMID: 8580738 DOI: 10.1016/0926-6410(95)90016-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The intent of the study was to determine whether altering the metabolism of neurosteroids via blockade of the enzyme, steroid sulfatase, could enhance retention test performance in rats. The steroid sulfatase inhibitor estrone-3-O-sulfamate (EMATE) was administered alone and in combination with the neurosteroid dehydroepiandrosterone sulfate (DHEAS) to rats which were then tested for the reversal of scopolamine induced amnesia. EMATE enhanced the reversal of amnesia by DHEAS as measured by a passive avoidance test. When administered without DHEAS, as a single acute dose, EMATE had no effect. When administered without DHEAS over 10 consecutive days, however, EMATE significantly improved retention. These results suggest that steroid sulfatase inhibition can potentiate the memory enhancing properties of DHEAS. The study also suggests that increasing the levels of endogenous sulfated neurosteroids via the inhibition of steroid sulfatase activity may enhance learning and/or memory function.
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Li PK, Leung NW, Poon AS, Wong KC, Chan TH, Lai KN. Molecular genetics of major histocompatibility complex class II genes in hepatocellular carcinoma. Dig Dis Sci 1995; 40:1542-6. [PMID: 7628281 DOI: 10.1007/bf02285206] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver with a possible genetic predisposition. We have studied the HLA-DQ and -DR regions of 57 unrelated HCC patients of southern Chinese origin using molecular DNA techniques and compared them with 104 normal controls. Seventy-six hepatitis B carriers (HBsAg) were also studied. Restriction fragment length polymorphism (RFLP) was used to genotype the MHC class II DR beta, DQ alpha and DQ beta loci of the subjects. Polymerase chain reaction (PCR) using sequence primer for DQ beta genes was also performed. No significant difference was found in the HLA-DQ and -DR loci between HCC patients and normal controls, HCC patients and HBsAg carriers, or HBsAg carriers and normal controls respectively. Forty-one HCC patients were HBsAg positive, and no difference was found in the HLA-DQ and -DR genotype between this group of patients compared with the group of normal controls or HBsAg carriers. Thirty-six HCC patients had elevated alpha-fetoprotein levels, and 15 HCC patients had normal levels. No difference in the HLA-DQ and -DR loci was detected between these two groups and the controls. The results suggest that HLA-DQ and -DR genotypes are not associated with hepatocellular carcinoma in southern Chinese.
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Li PK, Lui SF, Lai FM, Wang AY, Leung CB, Lai KN. Microscopic polyarteritis has a poor prognosis in Chinese. J Rheumatol 1995; 22:1295-9. [PMID: 7562761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To analyze retrospectively the clinical course and outcome of 10 consecutive Chinese patients with microscopic polyarteritis (MPA) admitted to our hospital over a period of 3 years. METHODS Ten patients with MPA who presented 1990-93 were studied. Their serum antineutrophil cytoplasmic autoantibody levels were assayed. RESULTS The male to female ratio was 1:1 and the mean age was 61 years. Eight patients (80%) had renal impairment on presentation and 5 of them (50%) were dialysis dependent. Seven patients (70%), during their clinical course, had pulmonary hemorrhage. Six patients (60%) had hypoxic lung disease requiring ventilatory support. All 10 patients were pANCA positive; 8 patients were tested for antimyeloperoxidase antibody and were all positive. Seven patients were treated with immunosuppressants consisting of steroid and cyclophosphamide with additional plasma exchange. Nine patients died after a mean survival of 9 months (range 1-33); causes of death were respiratory failure (5), infection (2), uremia (one), and stroke (one). The ANCA level reflected the disease activity of the vasculitis. CONCLUSION MPA in Chinese patients appeared to be a more severe disease with a poor prognosis. This may be related to the older age group, and the more frequent and severe pulmonary and renal manifestations of MPA in these patients.
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Li PK, Poon AS, Tsao SY, Ho S, Tam JS, So AK, Lai KN. No association between HLA-DQ and -DR genotypes with nasopharyngeal carcinoma in southern Chinese. CANCER GENETICS AND CYTOGENETICS 1995; 81:42-5. [PMID: 7773959 DOI: 10.1016/0165-4608(94)00205-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The pathogenesis of nasopharyngeal carcinoma (NPC) is multifactorial. Associations have been reported between HLA and NPC. We studied the HLA-DR and -DQ regions on the molecular level in 136 persons (51 NPC patients and 85 healthy controls) from southern China, a particularly high-prevalence area for NPC. Restriction fragment-length polymorphism (RFLP) was used to genotype the MHC class II DR beta, DQ alpha, and DQ beta regions of the subjects. Polymerase chain reaction (PCR) using sequence-specific primer (SSP) for DQ beta genes was also performed. By RFLP, no significant difference was observed with respect to DRB, DQA, and DQB genes. By PCR SSP typing, we confirmed that there was no significant difference between NPC patients and controls with respect to DQ beta alleles. Our study suggests that HLA-DQ and -DR genes are not associated with NPC in southern Chinese and there may be other gene loci that predispose them to have such a high prevalence of the disease.
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Li PK, Lai CK, Poon AS, Ho AS, Chan CH, Lai KN. Lack of association between HLA-DQ and -DR genotypes and asthma in southern Chinese patients. Clin Exp Allergy 1995; 25:323-31. [PMID: 7600378 DOI: 10.1111/j.1365-2222.1995.tb01050.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Asthma is an inflammatory disease with a strong genetic predisposition. We have studied a group of unrelated asthmatic patients of southern Chinese origin on their HLA-DR and -DQ regions using molecular techniques and compared them with 104 healthy controls of the same ethnic origin. Restriction fragment length polymorphism (RFLP) was used to genotype the MHC class II DR beta, DQ alpha and DQ beta loci of the subjects. Polymerase chain reaction (PCR) using sequence specific primer (SSP) for DQ beta genes was also performed. No significant difference was found in the HLA-DQ and -DR loci between the patients and the controls. All patients had their serum IgE antibody levels measured, bronchial reactivity assessed by histamine broncho-provocation and cutaneous reactivity to common allergens determined by skin-prick tests to Dermatophagoides pteronyssinus, Dermatophagoides farinae, mixed grass pollens, Aspergillus fumigatus, cat fur and dog dander and they were classified respectively. The HLA-DR and -DQ genotypes of these subgroups of patients were compared. There was no significant difference among these subgroups of patients according to their serum IgE levels, the degree of bronchial reactivity and whether they were positive for the skin tests for the various allergens respectively. The results suggest that HLA-DQ and -DR genotypes are not associated with asthma in southern Chinese people.
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Li PK, Mak TW, Wang AY, Lee YT, Leung CB, Lui SF, Lam CW, Lai KN. The interaction of fluvastatin and cyclosporin A in renal transplant patients. Int J Clin Pharmacol Ther 1995; 33:246-8. [PMID: 7620696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A possible interaction between fluvastatin, a new HMG CoA reductase inhibitor, and cyclosporin A (CsA) was studied in 16 stable renal transplant patients with dyslipoproteinemia despite dietary control. They entered a 12-week study period: 4-week baseline, 4-week placebo and 4-week fluvastatin treatment (20 mg daily). Weekly trough whole blood CsA concentrations were measured by monoclonal antibody immunoassay. Serial renal and liver function tests and creatine phosphokinase (CPK) were monitored. The mean trough levels of CsA during fluvastatin treatment were 115.6 micrograms/l compared with 114.3 micrograms/l and 113.3 micrograms/l in the baseline and placebo period, respectively. Apart from a small decrease in serum albumin level (from a mean of 38.6 g/l to 37.9 g/l), there were no significant changes in renal and liver functions or CPK levels. No adverse effects were reported. Fluvastatin (20 mg daily) may be used safely without extra monitoring of blood CsA concentrations in renal transplant patients.
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Abstract
The high serum concentration of estrone sulfate and the presence of estrone sulfatase in breast tumors constitute an important mechanism of local synthesis of estrogens in the tissue. Thus, inhibitors of estrone sulfatase may be effective in the treatment of estrogen-dependent breast cancer. In this study, we synthesized several isostructural analogs of estrone sulfate (estrone-3-methylsulfonate, estrone phosphate, 3-desoxyestradiol-3-methylenesulfonate, and 3-desoxyestrone-3-methylenesulfonate) and tested them on human placental sterylsulfatase. The results were (i) The Ki of 3-desoxyestrone-3-methylenesulfonate 12 and 3-desoxyestradiol-3-methylenesulfonate 7 are more than 100-fold higher than the Ki or KM values for estrone sulfate, (ii) As compared to estrone sulfate, the Ki value for estrone-3-methylsulfonate 2 is about 30-fold higher, while estrone phosphate 3 is bound by the sulfatase with roughly the same affinity as estrone sulfate. The results shed some light on the electronical and sterical requirements for high affinity binding to the enzyme.
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Abstract
We report a fatal case of heatstroke in an obese boy who developed multi-organ failure. Six other cases of exertional heatstroke admitted to our hospital over the last 5 years were also reviewed. All of them showed some degree of renal impairment. The causes of renal failure are multifactorial, with rhabdomyolysis being the major mechanism. All cases except one responded to alkaline diuresis without the need for dialysis. Continuous venovenous hemofiltration appeared to be a good alternative in hemodynamically unstable patients. Renal function recovered completely after varying intervals in all surviving cases. Interestingly, rhabdomyolysis in our heatstroke patients was usually associated with hypokalemia or normokalemia instead of hyperkalemia. Mortality in our series was largely related to the long duration of hyperthermia and coma, the severity of disseminated intravascular coagulation, and the presence of cardiogenic shock and severe acidosis.
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186
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Selcer KW, Li PK. Estrogenicity, antiestrogenicity and estrone sulfatase inhibition of estrone-3-amine and estrone-3-thiol. J Steroid Biochem Mol Biol 1995; 52:281-6. [PMID: 7696150 DOI: 10.1016/0960-0760(94)00176-m] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Estrogen levels in breast tumors of post-menopausal women are at least 10 times higher than estrogen levels in plasma. The high level of estrogen in these tumors is postulated to be due to in situ formation of estrogen, possibly through conversion of estrone sulfate to estrone by the enzyme estrone sulfatase. Thus, inhibitors of estrone sulfatase are potential agents for the treatment of hormone-dependent breast cancers. We designed and synthesized a series of estra-1,3,5(10)triene-17-one, 3-amino and estra-1,3,5(10)triene-17-one, 3-thio derivatives. We have shown previously that several of these compounds substantially inhibit estrone sulfatase, exceeding Danazol in their inhibitory activity. However, little is known about the metabolism of these compounds and the possible effects of their metabolites in vivo. Two probable metabolites of the synthetic estrone analogs are estra-1,3,5(10)triene-17-one, 3-amine (E1-NH2), and estra-1,3,5(10)triene-17-one, 3-thiol (E1-SH). We tested these two compounds for estrogenicity, antiestrogenicity and inhibition of estrone sulfatase activity using a combination of in vivo and in vitro assays. The ovariectomized rat uterine weight gain assay was used to test for estrogenicity. Neither E1-NH2 nor E1-SH were estrogenic, as indicated by a lack of uterine weight gain when given at 25 micrograms/day for 7 days. The test compounds also were not antiestrogenic, in that they did not block estrone-induced uterine weight gain when given (100 micrograms/day) simultaneously with estrone (2 micrograms/day). Both compounds showed low affinity for the estrogen receptor. Using rat uterine cytosol as a source of estrogen receptor, the compounds displaced only a small percentage of [3H]estradiol binding, even when present at 1000-fold excess. Inhibition of estrone sulfatase activity was tested using human placental microsomes as a source of estrone sulfatase. E1-NH2 and E1SH showed very low levels of estrone sulfatase inhibition (15.1 and 9.8%, respectively) under conditions where Danazol showed more than 60% inhibition. Our results indicate that neither of these two compounds would present significant problems if they were the primary metabolite in a treatment involving estrone sulfatase inhibition of estrogen-dependent breast cancer.
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187
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Mac-Moune Lai F, Li EK, Tang NL, Li PK, Lui SF, Lai KN. IgA nephropathy: a rare lesion in systemic lupus erythematosus. Mod Pathol 1995; 8:5-10. [PMID: 7731941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We describe three patients with a well-established clinical diagnosis of systemic lupus erythematosus in whom the renal biopsy lesion unexpectedly is diagnostic of IgA nephropathy, not superimposed with any features of lupus nephritis. Whereas the clinical presentation and follow-up of renal disease in these patients indicate a relatively indolent course, the extrarenal manifestations of systemic lupus erythematosys have been relatively severe, and one patient died of systemic infection. IgA nephropathy hitherto has not been described in patients with systemic lupus erythematosus, and such an observation stresses that atypical glomerular lesions in these patients should raise the possibility of a nonlupus glomerulopathy.
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188
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Lai KN, Leung JC, Li PK. Heat-aggregated IgA prepared from patients with IgA nephropathy increases priming of human neutrophils to produce inositol triphosphate following FMet-Leu-Phe stimulation in vitro. Nephron Clin Pract 1995; 69:1-8. [PMID: 7891778 DOI: 10.1159/000188352] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
It is envisaged that circulating IgA complexes play a primary role in the glomerular injury of IgA nephropathy, the most common glomerulonephritis worldwide. In this study, we examined the pathophysiological effects of IgA and IgG isolated from IgA-nephritic patients on the signal transduction of human neutrophils. Heat-aggregated forms and monomers of IgA and IgG were prepared from sera of 11 IgA-nephritic patients and 11 healthy controls. Signal transduction was studied by measuring the inositol triphosphate (IP3) production in neutrophils incubated with the immunoglobulin preparations. Different forms of IgA or IgG from IgA-nephritic patients failed to induce a significant increase in IP3 production directly as compared with control IgA or IgG. However, neutrophils preincubated with heat-aggregated IgA (HAA) from IgA-nephritic patients demonstrated a significant rise in IP3 production upon subsequent stimulation by a chemotactic peptide, FMet-Leu-Phe (FMLP); a similar finding was not observed with heat-aggregated IgG. HAA pretreatment of neutrophils increased FMLP-induced IP3 production in a dose-dependent manner. The raised IP3 production was not due to increased FMLP receptors, as HAA preincubation of neutrophils did not increase the binding of tritiated FMLP. The increased IP3 production upon FMLP stimulation in HAA-primed neutrophils was completely abolished by pertussis toxin in a dose-dependent manner. These findings tend to refute a direct stimulatory effect of HAA on phospholipase C, but, instead, may suggest that HAA prepared from IgA-nephritic patients upregulates the activation of G proteins in the plasma membrane.(ABSTRACT TRUNCATED AT 250 WORDS)
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Chan TH, Ho SS, Li PK. Noncardiogenic pulmonary edema associated with triazolam. JOURNAL OF TOXICOLOGY. CLINICAL TOXICOLOGY 1995; 33:185-7. [PMID: 7897760 DOI: 10.3109/15563659509000471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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190
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Lai KN, Ho RT, Leung JC, Chui YL, Lim PL, Lui SF, Li PK. CD4-positive cells from patients with IgA nephropathy demonstrate increased mRNA of cytokines that induce the IgA switch and differentiation. J Pathol 1994; 174:13-22. [PMID: 7965399 DOI: 10.1002/path.1711740104] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
IgA nephropathy (IgAN) is characterized by raised serum IgA1 and mesangial IgA1 deposits. We have previously shown increased T-cell activation in IgAN. Recently, transforming growth factor-beta (TGF-beta) has been shown to induce IgA isotype switch at a clonal level and interleukin 5 (IL5) promotes differentiation into IgA-bearing B cells. In the present study we have examined the TGF-beta and IL5 mRNA expression by mitogen-activated CD4-positive T cells from patients with IgAN (n = 25), patients with other primary nephritides (CGN) (n = 24), and healthy control subjects (n = 25). The cytokine genes were analysed by reverse transcription (RT)-polymerase chain reaction (PCR) and were semi-quantitated by normalizing the differences occurring during RT and PCR using a housekeeping gene, beta-actin. CD4-positive T cells from IgA nephritic patients expressed a higher level of IL5 mRNA than healthy controls (P < 0.01) and patients with CGN (P < 0.005). CD4-positive T cells from IgA nephritic patients expressed a higher level of TGF-beta mRNA than healthy controls (P < 0.01) but no difference was demonstrated on comparison with CGN patients. Elevated TGF-beta mRNA expression in patients with CGN probably reflects its other important function as a 'sclerogenic' factor involved in the glomerulosclerosis found in these nephritides. Our data suggest that there is increased expression of cytokine genes which induce the IgA isotype switch and differentiation; these immunological abnormalities may be important in the pathogenesis of IgAN.
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191
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Dibbelt L, Li PK, Pillai R, Knuppen R. Inhibition of human placental sterylsulfatase by synthetic analogs of estrone sulfate. J Steroid Biochem Mol Biol 1994; 50:261-6. [PMID: 7918111 DOI: 10.1016/0960-0760(94)90130-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Synthetic analogs of estrone sulfate which carry differently substituted sulfonyl groups at position 3 of an invariable 3-desoxyestrone (dE1) moiety were tested in vitro as inhibitors of the human placental sterylsulfatase. Using both placental microsomes and a highly purified placental sterylsulfatase preparation as the enzyme source and dehydroepiandrosterone [35S]sulfate or estrone [35S]sulfate as the substrate, the following order of inhibitory potencies was observed: dE1-3-sulfonylchloride > dE1-3-sulfonylfluoride approximately dE1-3-sulfonate > dE1-3-sulfonamide approximately 3-methylsulfonyl-dE1. According to the results, the association of enzyme and inhibitor appears to be favored by an electronegative substituent at the sulfur atom (-C1, -F, -O-). Since, however, even the most potent synthetic inhibitor was bound by the enzyme with significantly lower affinity than was the natural substrate estrone sulfate, an oxygen function between the aromatic ring and the sulfur atom may be necessary for high affinity binding towards the sterylsulfatase. In addition to its fast reversible association with the enzyme, dE1-3-sulfonylchloride further affected the sulfatase activity in a time-dependent manner. This latter inhibitory activity which may be due to a covalent modification (alkylation) of sterylsulfatase by the analog was partially prevented in the presence of substrate.
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Lai KN, Ho RT, Leung JC, Lai FM, Li PK. Increased mRNA encoding for transforming factor-beta in CD4+ cells from patients with IgA nephropathy. Kidney Int 1994; 46:862-8. [PMID: 7996808 DOI: 10.1038/ki.1994.343] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
IgA nephropathy (IgAN) is a mesangial proliferative glomerulonephritis characterized by predominant mesangial IgA deposits. Recently, transforming growth factor-beta (TGF-beta) is shown to exert widespread effects on extracellular matrix by enhancing its accumulation. In an experimental model of acute mesangial glomerulonephritis TGF-beta appeared to be involved in the process of glomerulosclerosis, and treatment with antagonists of TGF-beta prevented the development of glomerulosclerosis. We examined the TGF-beta mRNA expression by mitogen activated CD4+ T cells from 31 patients with IgAN, 25 healthy controls and 10 patients with minimal change nephropathy (MCN) or focal glomerulonephritis (FGN) who were comparable in age and sex. The cytokine gene was analyzed with reverse transcription followed by polymerase chain reaction and was semiquantitated by normalizing the differences occurring during reverse transcription and polymerase chain reaction using a housekeeping gene, beta-actin. CD4+ T cells from IgA nephritic patients expressed a higher level of TGF-beta mRNA than that of healthy controls or that of MCN/FGN [TGF-beta/actin ratio 1.11 (median), range 0.24 to 3.87 vs. 0.88, range 0.2 to 3.83, P = 0.0157 and 0.36 range 0.09 to 1.6, P = 0.006]. When the biopsies were classified into three grades according to the severity of glomerular and interstitial pathology, there were highly significant differences between the TGF-beta mRNA in CD4+ T cells from the three groups of IgA nephritic patients (grade 1, 0.52, range 0.24 to 0.79; grade 2, 1.2, range 0.5 to 3.33; grade 3, 2.17, range 1.45 to 3.87].(ABSTRACT TRUNCATED AT 250 WORDS)
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Li PK, Poon AS, Lai KN. Molecular genetics of MHC class II alleles in Chinese patients with IgA nephropathy. Kidney Int 1994; 46:185-90. [PMID: 7933837 DOI: 10.1038/ki.1994.258] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have studied the restriction fragment length polymorphism (RFLP) of the major histocompatibility complex (MHC) class II DQ and DR regions of 79 Chinese patients with IgA nephropathy (IgAN) and compared it with 104 normal Chinese controls. The DR and DQ alleles were confirmed by polymerase chain reaction using sequence specific primers. There was a significantly higher frequency of homozygous DQ beta 3b (DQ7) in patients with IgAN (16.4%) compared with controls (5.7%). Seventy-one IgAN patients had their renal biopsies graded according to histopathological severity: grades I, II or III. There was no statistical difference in the DR and DQ alleles among the three grades. Seventy-three patients were classified into group A with normal and stable renal function (serum creatinine < or = 150 mumol/liter) and group B with chronic renal failure (serum creatinine > 150 mumol/liter). There was a significant increase in frequency of DQA2 U (DX alpha U) allele in group B (66.9%) compared with group A (26.9%). Also, there was an increased frequency of DQ alpha 2 allele in the group A (40.4%) compared with group B (14.3%). Out of the 24 patients carrying the DQ alpha 2 allele, 17 were DQA2 U allele-negative and they all had normal renal function, suggesting that DQA2 U allele is associated with a poor prognostic factor in IgAN. The study shows that DQ alleles are probably the important genetic loci or are close markers for the disease susceptibility and prognostic index for IgAN in Chinese people.
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Li PK, Wang AY, Leung CB, Lui SF, Lai KN. Use of home automated intermittent peritoneal dialysis in the treatment of end stage renal failure. Int Urol Nephrol 1994; 26:353-8. [PMID: 7960548 DOI: 10.1007/bf02768221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We report our retrospective analysis of 16 uraemic patients who were treated with home automated intermittent peritoneal dialysis (IPD) from 1988 to 1993. Six patients were diabetic. The mean age was 58.5 years. The reasons for home automated IPD were: old age, poor eyesight, low intelligence or poor dexterity, family or patient request and old stroke. It took an average of 8.8 sessions to train the helper. The mean frequency of the home IPD was once every 5.8 days with a mean volume of 48 litres of dialysate used during each dialysis. There were 3 peritonitis episodes making the peritonitis rate once every 93 patient months. Four patients were still on home IPD and two were transplanted. Ten patients died of stroke, myocardial infarction, tuberculosis, chronic obstructive lung disease or suicide. A low plasma albumin is the only significant parameter in the early mortality group. Such high mortality can be accounted for by the fact that patients were older and forty per cent were diabetic. We conclude that home automated IPD can be an alternative for some patients in whom other modes of dialysis are difficult.
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195
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Lai FM, Li EK, Suen MW, Lui SF, Li PK, Lai KN. Pulmonary hemorrhage. A fatal manifestation in IgA nephropathy. Arch Pathol Lab Med 1994; 118:542-6. [PMID: 8192562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Two patients with asymptomatic IgA nephropathy (IgAN) and a third patient with chronic renal failure due to IgAN died following a recent onset of dyspnea, hemoptysis, and pulmonary infiltrates. In all cases, the cause of death was respiratory failure attributed to either bronchopneumonia or pulmonary edema. However, no infectious agent was identified. In all three patients, the diagnoses of IgAN and idiopathic pulmonary hemorrhage were established at postmortem examination. Acute alveolar hemorrhage was present in two patients. All three patients had heavy alveolar hemosiderin-laden macrophages, and capillaritis was recognized in two of them. The occurrence of fatal pulmonary hemorrhage in patients with IgAN is rare. Our findings suggested an immune complex-mediated pulmonary injury that was possibly related to the systemic nature of IgAN.
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Finn JE, Li PK, Lai KN, Mathieson PW. Molecular analysis of C3 allotypes in Chinese patients with immunoglobulin A nephropathy. Am J Kidney Dis 1994; 23:543-6. [PMID: 8154490 DOI: 10.1016/s0272-6386(12)80376-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The third component of complement (C3) exists in two main allotypic forms, C3S and C3F. An increased frequency of the rarer C3F allele has been reported in several autoimmune conditions, including immunoglobulin A nephropathy (IgAN), in white patients. C3F is known to be rare in the Chinese population, but C3 allotypes have not been studied in Chinese patients with IgAN. The molecular basis of the S/F polymorphism has been established recently: a single base change at the DNA level encodes a single amino acid substitution in the protein. A second polymorphism, closely linked to the first, is defined by the monoclonal antibody HAV 4-1, and also is due to a single base change. These polymorphisms therefore can be analyzed at the DNA level. We have used the amplification refractory mutation system, a modification of the polymerase chain reaction, to analyze these two C3 polymorphisms on genomic DNA from 133 Hong Kong Chinese individuals: 54 patients with IgAN and 79 controls. No C3F alleles were present in either group: all individuals were homozygous C3S. Twenty-six patients were also allotyped for the HAV 4-1 polymorphism; all 26 were homozygous HAV 4-1 negative, as would be predicted from the close linkage of this allotype to C3S in other populations. These data indicate that C3F is not a susceptibility allele for IgAN in Hong Kong Chinese individuals, and confirm in a large DNA-based study the rarity of C3F in this population.
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Lai KN, Ho RT, Lai CK, Chan CH, Li PK. Increase of both circulating Th1 and Th2 T lymphocyte subsets in IgA nephropathy. Clin Exp Immunol 1994; 96:116-21. [PMID: 7908616 PMCID: PMC1534550 DOI: 10.1111/j.1365-2249.1994.tb06240.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
IgA nephropathy (IgAN), characterized by glomerular deposition of IgA and frequently elevated plasma IgA levels, has increased T helper cell activity. In vitro measurement of cytokines in supernatant of cultured peripheral lymphocytes revealed conflicting findings. We examined the profile of cytokine mRNA expressed in purified CD4+ cells in patients with IgAN in order to study their pattern of Th1 (releases IL-2 and interferon-gamma (IFN-gamma)) and Th2 (releases IL-4 and IL-5) T cell response. We assessed the circulating CD4+ T cells in patients and normal controls by the expression of messenger RNA (mRNA) for IL-2, IL-4, IL-5 and IFN-gamma. The cytokine mRNAs were analysed with reverse transcription-polymerase chain reaction and were measured semiquantitatively by using a housekeeping gene, beta-actin. Compared with the control subjects, CD4+ T lymphocytes from patients with IgAN expressed a higher level of IL-2 mRNA (P = 0.007), IFN-gamma mRNA (P = 0.04), IL-4 mRNA (P = 0.048), and IL-5 mRNA (P = 0.016). Within these patients with IgAN, a good correlation was demonstrated between the gene expression of cytokines in Th1 or Th2 cells. The IL-2 mRNA levels in Th1 cells from these patients with IgAN also correlated significantly with the IL-4 or IL-5 mRNA levels in their Th2 cells. Our study revealed IgAN is associated with activation in circulating lymphocytes of the IL-2, IFN-gamma, IL-4 and IL-5 gene cluster, a pattern compatible with activation of both the Th1- and Th2-like T lymphocyte population. The increased transcription of these cytokines genes may be contributory to the immunopathologic findings in IgAN.
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198
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Lai FM, Lai KN, Tam JS, Lui SF, To KF, Li PK. Primary glomerulonephritis with detectable glomerular hepatitis B virus antigens. Am J Surg Pathol 1994; 18:175-86. [PMID: 8291656 DOI: 10.1097/00000478-199402000-00007] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The glomerular pathology and hepatitis B virus (HBV) antigens in renal biopsies were investigated in 100 consecutive patients with both primary glomerulonephritis and positive serology for hepatitis B surface antigen (HBsAg). Glomerular HBV antigens including HBsAg, hepatitis B core antigen (HBcAg), and hepatitis B e antigen (HBeAg) were examined in frozen tissue using both polyclonal and monoclonal antibodies. HBV serology and glomerular antigens were correlated. Using monoclonal antibodies, at least one of the three HBV antigens was detectable in glomeruli in 39% of the cases. These findings correspond mainly to detectable glomerular HBsAg and HBeAg in 22.3 and 28.4% of cases, respectively. A good correlation was found between glomerular and serum HBeAg but not observed for HBsAg. Serum HBcAg was not examined and not correlated with glomerular staining. When the diagnosis of HBV-related glomerulonephritis was based strictly on detectable glomerular antigens, three distinctive morphologies were identified: membranous nephropathy, mesangiocapillary glomerulonephritis, and mesangial proliferative glomerulonephritis with immunoglobulin A (IgA) deposits (IgA nephropathy). Each of these lesions may be seen in pure form or occasionally in overlapping form leading to double glomerulopathies. Glomerular HBeAg and HBsAg were associated with subepithelial and mesangial immune complexes, respectively. Rare overlap between membranous nephropathy and IgA nephropathy further emphasized the distinctive pathology of HBV-related glomerulonephritis and the independent etiological role of HBeAg and HBsAg. In other glomerulonephritis, which rarely demonstrated glomerular HBV antigens, the pathogenetic role of chronic HBV infection remains to be proven.
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Lui SF, Cheng AB, Leung CB, Wong KC, Li PK, Lai KN. Imipenem/cilastatin sodium in the treatment of continuous ambulatory peritoneal dialysis-associated peritonitis. Am J Nephrol 1994; 14:182-6. [PMID: 7977477 DOI: 10.1159/000168711] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Imipenem/cilastatin sodium is a new thienamycin class of antibiotic with a broad spectrum of bactericidal activities. It may be a suitable single first-line therapy for the treatment of peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients. Fifty episodes of CAPD peritonitis were treated with imipenem/cilastatin sodium. On presentation, all patients were given an intravenous loading dose of 1 g of imipenem/cilastatin sodium followed by intraperitoneal imipenem/cilastatin sodium for 10 days. During 1989 (30 episodes), 20 mg imipenem/cilastatin sodium was added to each 2-liter bag of peritoneal dialysis (PD) fluid for 10 days. The primary response rate as defined by polymorphonuclear neutrophils < 100/ml in PD fluid was 90%. Unfortunately, 17% of the peritonitis relapsed within 14 days of stopping antibiotic. The complete cure rate without relapse was therefore 73%. During 1990 (20 episodes), 100 mg imipenem/cilastatin sodium was added to each 2-liter bag of PD fluid for 10 days. The primary response rate was 95%, the complete cure rate without relapse was 85%. Imipenem/cilastatin sodium is an effective single first-line antibiotic for the treatment of peritonitis in CAPD.
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Lai KN, Wong KC, Li PK, Lai CK, Chan CH, Lui SF, Chui YL, Haskard DO. Circulating leukocyte-endothelial adhesion molecules in IgA nephropathy. Nephron Clin Pract 1994; 68:294-300. [PMID: 7530811 DOI: 10.1159/000188390] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
There is accumulating evidence that leukocyte-endothelial adhesion molecules are important in inflammatory injury in being involved in the primary step of entrapment and migration of leukocytes to the site of inflammation. We have used an antigen capture ELISA to measure the levels of circulating intercellular adhesion molecule-1 (cVCAM-1), vascular cell adhesion molecule-1 (cVCAM-1) and E selectin (cE selectin) in the peripheral blood of 33 patients with IgA nephropathy (IgAN) during clinical quiescence and 24 healthy controls. The serum levels of cICAM-1 and E selectin in IgA-nephritic patients were not different from that of healthy controls but the cVCAM-1 level was significantly elevated in IgAN despite a lack of clinical activity (p = 0.008). The differential rise of circulating leukocyte-endothelial adhesion molecules in IgAN probably reflects the origins and nature of these molecules as well as the specific immunological profile of IgAN. There was no correlation between the levels of these three circulating adhesion molecules. When the patients with IgA nephropathy were stratified according to the severity of their glomerular and interstitial lesions, there was an apparent increase in cE selectin and cVCAM-1 associated with increased histopathologic grading. The changes in endothelial adhesion molecules during clinical exacerbation were studied in 10 patients. Coinciding with synpharyngitic macrohematuria, there was a significant rise of cVCAM-1 and cE selectin (p = 0.046 and p = 0.016, respectively) but no similar rise was observed in cICAM-1.(ABSTRACT TRUNCATED AT 250 WORDS)
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