Reassessment of spiny dogfish Squalus acanthias age and growth using vertebrae and dorsal-fin spines.

Male and female spiny dogfish Squalus acanthias were collected in the western North Atlantic Ocean in the Gulf of Maine between July 2006 and June 2009. Squalus acanthias ranged from 25 to 102 cm stretch total length and were caught during all months of the year except January. Age estimates derived from banding patterns visible in both the vertebrae and second dorsal-fin spines were compared. Vertebral growth increments were visualized using a modified histological staining technique, which was verified as appropriate for obtaining age estimates. Marginal increment analysis of vertebrae verified the increment periodicity, suggesting annual band deposition. Based on increased precision and accuracy of age estimates, as well as more biologically realistic parameters generated in growth models, the current study found that vertebrae provided a more reliable and accurate means of estimating age in S. acanthias than the second dorsal-fin spine. Age estimates obtained from vertebrae ranged from <1 year-old to 17 years for male and 24 years for female S. acanthias. The two-parameter von Bertalanffy growth model fit to vertebrae-derived age estimates produced parameters of L∞ = 94·23 cm and k = 0·11 for males and L∞ = 100·76 cm and k = 0·12 for females. While these growth parameters differed from those previously reported for S. acanthias in the western North Atlantic Ocean, the causes of such differences were beyond the scope of the current study and remain to be determined.

A new in vivo model for luteolysis using systemic pulsatile infusions of PGF(2α).

A new in vivo model for studying luteolysis was developed in sheep to provide a convenient method for collecting corpora lutea for molecular, biochemical, and histological analysis during a procedure that mimics natural luteolysis. It was found that the infusion of prostaglandin F(2α) (PGF(2α)) at 20 µg/min/h into the systemic circulation during the mid luteal phase of the cycle allowed sufficient PGF(2α) to escape across the lungs and thus mimic the transient 40% decline in the concentration of progesterone in peripheral plasma seen at the onset of natural luteolysis in sheep. Additional 1h-long systemic infusions of PGF(2α), given at physiological intervals, indicated that two infusions were not sufficient to induce luteolysis. However, an early onset of luteolysis and estrus was induced in one out of three sheep with three infusions, two out of three sheep with four infusions, and three out of three sheep with five infusions. Reducing the duration of each systemic infusion of PGF(2α) from 1h to 30 min failed to induce luteolysis and estrus even after six systemic infusions indicating that, not only are the amplitude and frequency of PGF(2α) pulses essential for luteolysis, but the actual duration of each pulse is also critical. We conclude that a minimum of five systemic pulses of PGF(2α), given in an appropriate amount and at a physiological frequency and duration, are required to mimic luteolysis consistently in all sheep. The five pulse regimen thus provides a new accurate in vivo model for studying molecular mechanisms of luteolysis.

Short communication: Rapid antibiotic screening tests detect antibiotic residues in powdered milk products.

Rapid antibiotic screening tests are widely used in the dairy industry to monitor milk for the presence of antibiotic residues above regulated levels. Given the persistent concern over contamination of milk products with antibiotic residues, we investigated the utility of IDEXX Snap test devices (IDEXX Laboratories Inc., Westbrook, ME) as tools for detecting antibiotic residues in powdered milk products. Five powdered milk products were reconstituted according to manufacturer specification with distilled water: Carnation (Nestlé USA Inc., Solon, OH), Nido youth and Nido adult (Nestlé Mexico Inc., Mexico City, Mexico), ELK (Campina, Eindhoven, the Netherlands), and Regilait (Saint-Martin-Belle-Roche, France). Positive samples were generated by spiking reconstituted milk with penicillin G, cephapirin, or tetracycline to either the European Union-regulated maximum residue limit or the FDA-regulated safe/tolerance level, whichever was lower. Control, unspiked negative milk samples and positive samples were tested with appropriate IDEXX Snap test kits (penicillin G and cephapirin with New Beta-Lactam, tetracycline with New Tetracycline). All samples yielded definitive results consistent with expectations, and there were no instances of false-positive or false-negative readings. These results suggest that both the New Beta-Lactam and New Tetracycline IDEXX Snap test kits effectively detect antibiotic residues in commercially available powdered milk samples and are useful tools for monitoring antibiotic residues in reconstituted powdered milk products.

Age and size at sexual maturity of the smooth skate Malacoraja senta from the western Gulf of Maine.

Age and size at sexual maturity was determined for 185 male and 96 female smooth skates Malacoraja senta (ranging in size from 370 to 680 mm total length L(T)), collected from the western Gulf of Maine. Maturity ogives for males, based on clasper length, testis mass and the proportion of mature spermatocysts in the testes, suggest that 50% maturity occurs between 9 and 10 years and 560 mm L(T). Maturity ogives for females, based on ovary mass, shell-gland mass and maximum follicle size, suggest that 50% maturity occurs at age 9 years and 540 mm L(T).

Size and age estimates at sexual maturity for the little skate Leucoraja erinacea from the western Gulf of Maine, U.S.A.

Size and age estimates at sexual maturity were determined for 162 male and 273 female little skates Leucoraja erinacea collected from the western Gulf of Maine. Maturity ogives suggest that 50% maturity in females occurs at age 9.5 years and 480 mm total length (LT), whereas 50% maturity in males occurs at a slightly younger age of 7.7 years and smaller size of 460 mm LT. Age estimates were made from 389 L. erinacea ranging in size from 93 to 570 mm LT. The index of average per cent error and age-bias plots indicated that the ageing methods were precise and non-biased. Additionally, annual periodicity of band formation was validated with oxytetracycline in eight individuals (three males and five females) ranging in age from 3 to 12 years. In conclusion, results from this study indicate that L. erinacea exhibits characteristics that make other elasmobranch populations highly susceptible to overexploitation.

Knowledge of and attitudes toward severe acute respiratory syndrome among a cohort of dental patients in Hong Kong following a major local outbreak.

OBJECTIVE: To assess the knowledge of and attitudes toward severe acute respiratory syndrome (SARS) among patients attending a teaching dental hospital and private dental practices in Hong Kong during a major local SARS outbreak. METHODS: 250 dental patients were interviewed by questionnaire and 213 were interviewed by phone. RESULTS: Less than one-third (30.0%) of the 463 respondents said they were not afraid of contracting the SARS coronavirus from their dentists and did not avoid dental treatment for that reason. Nearly three-fifths (56.7%) did not worry about contracting SARS from dental treatment. Fewer than 10% of the respondents thought that dentists ran a high risk of contracting SARS. From the patients' experiences, 85.2% and 21.7% of the dentists wore face masks and face shields, respectively, when delivering dental treatment. CONCLUSIONS: The majority of patients interviewed had confidence in their dentists, their treatment environments, and the infection control measures taken, and were not worried about contracting SARS in the dental setting. This perception is an improvement from that described in an earlier study, in which more than half of the patients were concerned about contracting an infection during dental treatment and perceived that the infection control measures undertaken by the dental profession to prevent infectious diseases were not satisfactory. Patients, however, demanded better infection control measures during the SARS outbreak.

Methylation profile in benign, borderline and malignant ovarian tumors.

PURPOSE: Promoter hypermethylation is a common phenomenon in neoplasm. The aims of this study were (a) to compare the methylation profiles in different types of ovarian tumors and (b) to determine the possible relationship between the methylation status and different clinicopathologic characteristics. METHODS: We examined the promoter methylation status of 9 tumor suppressor genes (RARbeta2, TMS1, RIZ1, P15, P16, PTEN, MINT31, APC and HIC1) in 89 ovarian cancers, 16 borderline ovarian tumors, 19 benign ovarian tumors, 16 normal ovarian tissue and 5 ovarian cancer cell lines. The methylation status was examined with respect to clinicopathologic characteristics of the ovarian cancer patients. RESULTS: Methylation indices for ovarian cancer, borderline ovarian tumor, benign ovarian tumor, normal ovarian tissue and ovarian cancer cell lines were 28.8, 20.1, 10.5, 11.8 and 42.2%, respectively. It was significantly higher in ovarian cancer, borderline ovarian tumor and ovarian cancer cell lines (X (2) test, P < 0.001, P = 0.01 and P < 0.001, respectively) than benign or normal ovarian tissues. In ovarian cancer, concurrent methylation of at least two genes (CM2) was associated with early stage disease (X (2) test, P = 0.035) and less recurrence (X (2) test, P = 0.020). When the methylation statuses of the nine genes as well as CM2 were included in multivariate Cox Regression analysis, CM2 was the only independent predictor for survival (P = 0.013). CONCLUSION: CM2 was an independent predictor for survival in ovarian cancer.

Hong Kong men with low incomes have worse health-related quality of life as judged by SF-36 scores.

OBJECTIVE: To analyse the association between income and health-related quality of life using the Medical Outcome Study Short Form 36 (SF-36) Chinese version in Hong Kong Chinese working population. DESIGN: Cross-sectional observation study. SETTING: A commercial company in Hong Kong. PARTICIPANTS: All clerical and administrative staff of a commercial company was invited to participate; 876 of the 1003 staff agreed. The subjects were categorised into three income groups according to monthly income in Hong Kong dollars (low, < or =10,000; middle, >10,000-25,000; high, >25,000). The mean age of the 288 men and 588 women was 34.9 (standard deviation, 7.9; median, 34.0; range, 18-71) years. MAIN OUTCOME MEASURES: SF-36 scores on health-related quality of life. RESULTS: The distribution of income was 30% in high-, 54.8% in middle-, and 15.2% in low-income groups. Women had similar SF-36 scores among different income groups. In men, for most variables there was a significant positive linear correlation between income and SF-36 scores. CONCLUSION: Low income is associated with a worse health-related quality of life in Hong Kong Chinese men.

Chlortetracycline supplementation of yearling dairy heifers.

Chlortetracycline is an antibiotic that is used to increase weight gain, efficiency of gain, carcass grade, and conception rates. The objective of this experiment was to evaluate the effects of supplementation of 350 mg/d of chlortetracycline on ADG, G:F, BCS, thyroxine, and systemic glucose concentrations in yearling dairy heifers. Forty 12-mo-old Holstein heifers (initial BW = 363 +/- 21 kg) were housed in a free-stall barn with ad libitum access to feed and water for 104 d. A transition period was begun 14 d before the age of 12 mo to acclimate the heifers to the diet. The chlortetracycline-fed group (n = 20) consumed 328 +/- 8.2 mg of chlortetracycline/heifer daily. Measurements for BW, withers and hip heights, BCS, and health score were recorded weekly. Dry matter intake was measured daily. Blood was sampled every 4 d to determine plasma thyroxine and glucose concentrations and every 2 d to determine progesterone concentrations. Heifers were artificially inseminated on the first observed standing heat after 13 mo of age. There were no effects of chlortetracycline on ADG, G:F, withers and hip heights, BCS, blood glucose concentrations, peak progesterone concentrations, health, or conception rate. There was an interaction between treatment and time for chlortetracycline on serum thyroxine concentration. In the beginning of the experiment, serum thyroxine concentration was lower in heifers supplemented with chlortetracycline. There was no difference between treatments in thyroxine concentration at the end of the experiment. Chlortetracycline supplementation was not beneficial for yearling dairy heifers.

Microsatellite instability in mitochondrial genome of common female cancers.

To investigate the occurrence of mitochondrial genome instability in primary cervical, endometrial, ovarian, and breast carcinomas, we analyzed 12 microsatellite regions in mitochondrial DNA (mtDNA) of tumor tissues and their matched normal controls. Four of the 12 microsatellite markers starting at nucleotide position (np) 303, 514, 956, and 16184, respectively, exhibited instability as indicated by the change in length of short base-repetitive sequences of mtDNA in cancer tissue relative to that in control normal tissue from the same patient. About 25.4% of cervical cancers, 48.4% of endometrial cancers, 21.9% of ovarian cancers, and 29.4% of breast cancers carried one or more mitochondrial microsatellite instability (mtMSI). mtMSI was frequently detected in the D-loop region but rarely occurred in the coding region. A relatively long C tract interrupted by a T residue is the mtMSI hot spot in all four types of cancer studied. Different tumors have different mtMSI profiles. In particular, the frequency of mtMSI in endometrial cancer was significantly higher than in the other three types of cancer. Furthermore, carriers of a germ-line T to C polymorphism at np 16189 could be more susceptible to breast cancer development in light of the higher frequency detected in cancer patients than in normal individuals.

Potential application of the ATP cell viability assay in the measurement of intrinsic radiosensitivity in cervical cancer.

BACKGROUND: Intrinsic radiosensitivity using the clonogenic assay and the cell surviving fraction at 2 Gy (SF2) has been shown to be an independent prognostic factor for patient response to radiotherapy in carcinoma of the cervix. The clonogenic assay has significant shortcomings, making it unsuitable for routine clinical use. The ATP cell viability assay (ATP-CVA) has been shown to have a high tumor evaluability rate, technical simplicity, and reproducibility in chemosensitivity testing. AIMS: This study compares the ATP-CVA with the clonogenic assay in the in vitro radiosensitivity testing of cervical cancer cell lines. Correlation of in vitro radiosensitivity and in vivo patient response was also determined. METHODS: Five cervical carcinoma cell lines (SiHa, HeLa, Caski, C-33A, and C4-1) were tested using the ATP-CVA and the clonogenic assay. Survival curves were plotted and the mean SF2 values obtained by the two different assay methods were compared using ANOVA to see if there were significant differences. Mean SF2 values obtained from 27 cervical cancers were compared with clinical outcomes. RESULTS: The SF2 values for the cell lines ranged from 0.28 to 0.67 when tested using the ATP-CVA. Using the clonogenic assay, the SF2 values ranged from 0.27 to 0.70. ANOVA with Bonferroni pairwise multiple comparison showed no significant difference between the mean SF2 values for the individual cell lines between the two assay methods. Twenty-three cervical cancer samples (85%) were evaluable for SF2 using ATP-CVA. The mean SF2 values of patients who had locoregional failure were significantly higher than those who achieved local control (P <0.01). CONCLUSIONS: Testing intrinsic radiosensitivity using the surviving fraction at 2 Gy (SF2) is comparable using the two assay methods of ATP-CVA and clonogenic assay. The ATP-CVA should be further investigated in the testing of intrinsic radiosensitivity in patients with cervical cancer.

Quantification of human papillomavirus DNA in the plasma of patients with cervical cancer.

Plasma human papillomavirus (HPV)-DNA level was measured to evaluate the clinical usefulness of circulating DNA for cervical cancer management. DNA extracted from pretreatment plasma of 50 cervical cancer patients and from serial longitudinal plasma of 21 patients was quantified for HPV16/HPV18 by means of quantitative polymerase chain reaction. Another 15 patients with low-grade lesion (LG), 18 patients with high-grade lesion (HG), and 96 normal individuals were studied as controls. Plasma HPV16-DNA was detectable in 50% of cancer patients. The incidence and median level were statistically higher than those in LG patients and normal, but similar to HG patients. Plasma HPV18-DNA was only detected in 6% of cancer patients and 1% of normal. Same type of HPV present in plasma was also detected in its primary tumor; and the level of plasma HPV16-DNA was dependent on the viral load in primary tumor. Plasma HPV-DNA was not detected in 16 of 21 patients after treatment, and those patients had complete response to therapy. HPV-DNA persisted or reappeared in five patients after treatment (one had persistent disease and another had recurrence). Plasma HPV-DNA might be a valuable marker for monitoring therapeutic response and disease progression in cervical cancer.

Detection of hypermethylated genes in tumor and plasma of cervical cancer patients.

OBJECTIVE: The aim of this study is to investigate the prevalence of promotor CpG island methylation of the death-associated protein kinase (DAPK), p16, and O(6)-methylguanine-DNA methyltransferase (MGMT) genes in both tumor and plasma samples of cervical cancers. METHODS: Methylation-specific PCR (MSP) was employed to detect promotor CpG island methylation of the DAPK, p16, and MGMT genes in 85 surgical tumor tissue samples and 40 pretreatment plasma samples from cervical cancers. RESULTS: Promotor CpG island methylation of DAPK, p16, and MGMT was detectable, respectively, in 60%, 28.2%, and 18.8% of cases of cervical tumor DNA; and in 40%, 10%, and 7.5% of cases of patients' plasma DNA. Moreover, at least one of the three methylated genes was detected in 75.3% (64/85) of cases of tumor and in 55% (22/40) of cases of plasma. Higher prevalence of methylation of DAPK was found in squamous cell carcinoma than in adenocarcinoma in both univariate and multivariate analysis. Methylation of p16 was significantly associated with that of MGMT in both univariate and multivariate analysis. The methylation pattern in primary tumor and plasma was found to be concordant in 23 patients with matched tissue and plasma samples. In cases positive for DAPK and p16 methylation in tumor, detection in the paired plasma sample was 64.3% (9/14) and 33.3% (3/9), respectively. CONCLUSIONS: Promotor CpG island methylation is a frequent event in cervical carcinogenesis. Detection of the methylated sequences in the circulation suggests that plasma DNA methylation warrants further study to determine its potential role in cancer management.

High frequency of mitochondrial genome instability in human endometrial carcinomas.

To investigate the occurrence of somatic mitochondrial DNA (mtDNA) mutations in human primary endometrial carcinomas, we sequenced the D-loop region, the 12S and 16S rRNA genes of mtDNA of cancer tissues and their matched normal controls. About 56% (28 out of 50) of cases carry one or more somatic changes in mtDNA including deletion, point mutation and mitochondrial microsatellite instability (mtMSI), namely the change in length of short base-repetitive sequences of mtDNA. In particular, mtMSI was frequently detected in 89% (25 out of 28) of all the cases carrying somatic changes followed by point mutations (25%; seven out of 28) and deletion (3.5%; one out of 28). The CCCCCTCCCC sequences located in the Hypervariable Regions I and II of the D-loop and 12S rRNA gene are instability hot spot regions in endometrial carcinomas. It is suggested that errors in replication may account for the high frequency of mtMSI in human endometrial carcinomas. The relatively high prevalence of mtMSI may be a potential new tool for detection of endometrial cancer.

Detection of human papillomavirus DNA in malignant lesions from Chinese women with carcinomas of the upper genital tract.

OBJECTIVE: The aim of this study was to determine the prevalence of high-risk oncogenic human papillomaviruses (HPVs) in malignant lesions from Hong Kong Chinese women with carcinomas of the upper genital tract. METHODS: The presence of high-risk HPVs in 55 cases of endometrial adenocarcinomas and 60 cases of primary epithelial ovarian cancers was detected by polymerase chain reaction (PCR) using consensus primers complementary to late 1 (L1) gene of the genital HPVs. Amplified PCR products were verified and typed by Southern blot analysis using (32)P-labeled DNA probes prepared from cloned HPV-16 and -18 plasmids. To confirm the presence of high-risk HPV types in the tumor tissues, PCR amplification using HPV type 16- and 18-specific primers for part of the E6 gene were also carried out. RESULTS: While HPV-18 was not detected, HPV-16 DNA sequences were identified in 5 (9.1%) of the 55 studied endometrial carcinoma samples. Of the 5 HPV-16-positive cases, there were 4 stage I, and 1 stage II endometrial cancer. In addition, 6 (10%) of the 60 epithelial ovarian carcinomas were positive for high-risk HPVs, which included 5 cases with HPV-16 and 1 case with HPV-18. Clinical staging revealed that 5 of the 6 HPV-positive cases were stage I and the remaining case was stage III ovarian cancer. Histology of the 6 HPV-positive cases showed that there were 1 case of clear-cell adenocarcinoma, 1 case of mucinous cystadenocarcinoma, and 4 cases of mucinous tumor of borderline malignancy. No other HPV types were detected. CONCLUSION: High-risk HPV was detected in approximately 10% of the tumor samples from women with upper genital tract carcinomas. As compared to the high positive rate of HPV infections in cervical cancer, it appears that HPV infection plays a relatively minor role in the pathogenesis of endometrial and ovarian carcinomas.

Relationship of fertility to ovarian follicular waves before breeding in dairy cows.

Cows with two waves of follicular growth during the estrous cycle yield follicles that are older and larger at ovulation compared with cows having three waves. The objectives of the current research were 1) to compare fertility in cows with two or three follicular waves and 2) to examine associations between luteal function, follicular development, and fertility after breeding. Follicular waves were monitored by ultrasonography during the estrous cycle before insemination in 106 dairy cows. Fewer cows had three follicular waves before next estrus and ovulation than two waves (P < 0.01; 30% vs 68%, respectively), but pregnancy rate was higher (P = 0.058; 81 vs 63%, respectively). Cows with two waves had shorter estrous cycles (P < 0.01), with the ovulatory follicle being both larger (P < 0.05) and older (P < 0.01). In cows with three waves, luteal function was extended (P < 0.05) and the peak in plasma progesterone occurred later (P < 0.05) in the estrous cycle compared to two wave cows. Considering cows that became pregnant, luteal phase length was shorter (P < 0.05) during the estrous cycle preceding insemination than for nonpregnant cows. In conclusion, fertility was greater in lactating cows inseminated after ovulation of the third-wave follicle that had developed for fewer days of the estrous cycle as compared with two-wave cows.

Heterogeneity in antifungal susceptibility of clones of Candida albicans isolated on single and sequential visits from a HIV-infected southern Chinese cohort.

The increased frequency and severity of candidal infections in human immunodeficiency virus (HIV)-infected individuals has prompted the wide use of antifungals, such as amphotericin B, ketoconazole, and fluconazole, resulting in the emergence of drug-resistant strains of Candida albicans. To study this phenomenon in an ethnic Chinese cohort, we isolated multiple colonies of Candida from the oral cavities of 16 HIV-infected patients on single and subsequent sequential visits over a period of 12 months. Ten of the 16 patients had sporadic episodes of oropharyngeal candidiasis (Group A), while the remainder were asymptomatic with respect to this condition (Group B). Oral rinses were collected and immediately processed in the laboratory for the isolation of C. albicans in a standard manner. A total of 433 C. albicans isolates were tested for their susceptibility to amphotericin B, ketoconazole and fluconazole by an agar diffusion method using the commercially available E-test. All tested isolates demonstrated variable susceptibility to amphotericin B, ketoconazole and fluconazole. The minimum inhibitory concentration (MIC) of the isolates for amphotericin B, ketoconazole and fluconazole ranged from <0.002-1.5 microg/ml, <0.002-4.0 microg/ml and <0.016-32 microg/ml, respectively. Sequential isolates of a few patients demonstrated variable susceptibility to all the antifungals, and no discernible MIC pattern emerged either in group A or B over time. Interestingly, significant variation in antifungal susceptibility was also noted in isolates obtained from the same patient on a single visit. Sequential yeast isolates in 9 of 16 patients (56%) demonstrated significant differences in MIC within and between visits for both amphotericin B and ketoconazole, while a lower percentage--44%(7/16)--exhibited this trait for fluconazole. Our study demonstrates the diversity in antifungal susceptibility in either commensal or "infective" oral strains of C. albicans in HIV disease, and shows the need for vigilance for the emergence of resistant strains, and for frequent antifungal susceptibility studies.

Oral health status, oral microflora, and non-surgical periodontal treatment of renal transplant patients receiving cyclosporin A and FK506.

OBJECTIVES: To determine the oral health status, oral microflora and the effect of non-surgical periodontal treatment on gingival overgrowth of renal allograft recipients receiving either cyclosporin A (CsA) or FK506 (Tacrolimus) as an immunosuppressant. MATERIALS AND METHODS: A total of 47 patients receiving CsA (mean age 43.1 years) and 10 receiving FK506 (mean age 40.1 years) were included in the study. Stone casts were taken for measurement of gingival overgrowth. An oral rinse technique was used to investigate the prevalence of yeasts, and aerobic and facultatively anaerobic Gram-negative rods (AGNR). RESULTS: The CsA and FK506 patients exhibited a Gingival Overgrowth Index (GOI) of 45.2%, and 25.1%, respectively (p < 0.05). The CsA patients had a GOI of 15.2% after one year of non-surgical periodontal treatment. The difference between pre- and postoperative gingival overgrowth indices was significant (p < 0.0001). Candida albicans and Klebsiella pneumoniae were the most notable yeast and AGRN found. CONCLUSIONS: Renal transplant patients, being immunocompromised, constitute a high-risk group for gingival overgrowth. However, the FK506 regime appeared to ameliorate this effect, compared with CsA. Non-surgical periodontal treatment was effective in reducing established gingival overgrowth in both CsA and FK506 patients (p < 0.05). Adequate pre- and post-transplant oral health care is recommended, for these patients, irrespective of the drug regime.

Oral manifestations of HIV infection in a group of predominantly ethnic Chinese.

A total of 32 HIV-infected, predominantly ethnic Chinese individuals from Hong Kong were examined for oral mucosal lesions over a period of 1 year. The commonest oral lesion found was minor aphthous ulceration (27.4%), while xerostomia (17.8%), ulceration NOS (not otherwise specified; 12.3%), hairy leukoplakia (11.0%) and erythematous candidiasis (6.9%) were less frequent; Kaposi's sarcoma was notable for its absence. When the relationship between the number of oral lesions with age, risk group, medication taken, CDC staging and CD4+ count of the study group was investigated, a significantly higher number of oral lesions was associated with use of AZT, homosexuals and CDC stage IV; in contrast, a smaller number of lesions was found in those on antiparasitics and multivitamins (all P<0.05). When compared with studies from other parts of the world, the frequency of oral lesions appeared to be less common in the current study group. However, due to a lack of similar studies from the Asian region, especially in ethnic Chinese, it is not clear whether this difference could be attributed to racial, social or geographic factors.