Biomedical subjects

L Cheng

Publications and source records attributed to L Cheng.

At least 91 records · Page 5Linked to original sources

PubMed2000

Targeted disruption of NDST-1 gene leads to pulmonary hypoplasia and neonatal respiratory distress in mice.

In order to address the biological function of GlcNAc N-deacetylase/N-sulfotransferase-1 (NDST-1), we disrupted the NDST-1 gene by homologous recombination in mouse embryonic stem cells. The NDST-1 null mice developed respiratory distress and atelectasis that subsequently caused neonatal death. Morphological examination revealed type II pneumocyte immaturity, which was characterized by an increased glycogen content and a reduced number of lamellar bodies and microvilli. Biochemical analysis further indicated that both total phospholipids and disaturated phosphatidylcholine were reduced in the mutant lung. Our data revealed that NDST-1 was essential for the maturation of type II pneumocytes and its inactivation led to a neonatal respiratory distress syndrome.

Amidohydrolases↗

PubMed2000

Inverted urothelial papilloma: is ploidy, MIB-1 proliferative activity, or p53 protein accumulation predictive of urothelial carcinoma?

BACKGROUND: Inverted urothelial papilloma is an unusual neoplasm of the urinary tract. Although the association between inverted urothelial papilloma and urothelial carcinoma is not entirely clear, many studies indicate that patients with inverted papilloma are at increased risk for the development of urothelial carcinoma. In addition, aneuploid inverted papillomas have been associated with the subsequent development of urothelial carcinoma. The objective of this study was to determine whether ploidy, MIB-1 proliferative activity, or p53 protein staining in inverted papilloma were predictive of urothelial carcinoma. METHODS: Fifty-one cases of inverted papilloma were retrieved from the Tissue Registry of the Mayo Clinic. Clinical records were reviewed for patient age, length of follow-up, and history of urothelial carcinoma (defined as carcinoma prior to, concurrent with, or subsequent to the diagnosis of inverted papilloma). DNA ploidy analysis was determined using Feulgen stained sections from paraffin embedded tissues using an image analysis system. Quantitation of MIB-1 proliferative activity and p53 immunostaining was determined similarly using immunoperoxidase stained sections from paraffin embedded tissues. RESULTS: The mean age at diagnosis of inverted papilloma was 63.9 years (range, 37-87 years), and there were 39 men and 12 women. Patients were followed for a mean of 56.5 months (range, 1-252 months). Tumors ranged in size from 0.2 to 4.3 cm (mean, 0.9 cm). Eight patients (15.7%) had a prior, concurrent, or subsequent noninvasive World Health Organization and International Society of Urologic Pathology (WHO/ISUP) papillary neoplasm of low malignant potential or papillary carcinoma of low grade (formerly WHO Grade 1 or 2 papillary urothelial carcinoma). Inverted papillomas in patients with a history of urothelial carcinoma were all diploid and had a mean MIB-1 activity of 6.3% (range, 0.04-24.8%) and mean p53 protein staining of 12.6% (range, 0.5-24.9%). These inverted papillomas ranged in size from 0.3 to 1.0 cm (mean, 0.5 cm). Inverted papillomas in patients without a history of urothelial carcinoma were aneuploid in 6 cases (14.3%) and diploid in the remaining cases. These inverted papillomas had a mean MIB-1 activity of 1.6% (range, 0.06-9.0%) and mean p53 protein staining of 9.7% (range, 0.05-38.0%). Tumor size ranged from 0.2 to 4.3 cm (mean, 1.0 cm). There were no statistically significant differences in MIB-1 activity, p53 protein staining, ploidy, and morphologic features between inverted papillomas in patients with and without a history of urothelial carcinoma. CONCLUSIONS: Ploidy, MIB-1 proliferative activity, and p53 immunostaining in inverted urothelial papilloma were not useful in identifying patients who had a history of urothelial carcinoma.

Adult↗

PubMed2000

Flat intraepithelial lesions of the urinary bladder.

BACKGROUND: In the 1998 World Health Organization and International Society of Urologic Pathology (WHO/ISUP) classification system for bladder neoplasms, flat intraepithelial lesions of the urinary bladder were categorized as reactive atypia, atypia of unknown significance, dysplasia, and carcinoma in situ. The clinical outcomes of patients diagnosed with these atypical urothelial proliferations are uncertain. METHODS: The authors studied a series of patients who were diagnosed with reactive atypia of the urinary bladder (25 patients), urothelial atypia of unknown significance (35), or urothelial dysplasia (26) between 1985 and 1993. All histologic slides were reviewed and classified according to the 1998 World Health Organization and International Society of Urologic Pathology classification system. Patients with a concomitant or prior history of carcinoma in situ or urothelial carcinoma were excluded. RESULTS: Patient age at diagnosis ranged from 24 to 88 years (mean, 65 years). The male-to-female ratio was 3:1. The mean follow-up was 3.9 years (range, 0.1-13.4 years; median, 3.5 years). None of the patients with reactive atypia or atypia of unknown significance developed dysplasia, carcinoma in situ, or urothelial carcinoma. Four patients (15%) with urothelial dysplasia developed biopsy-proven cancer, including 3 patients with muscle-invasive cancer. The mean interval from the diagnosis of urothelial dysplasia to the development of cancer was 4.5 years. CONCLUSIONS: Patients with a diagnosis of urothelial atypia of unknown significance or reactive atypia do not have adverse clinical outcomes, whereas patients with urothelial dysplasia of the bladder have an increased risk for the development of carcinoma in situ and urothelial carcinoma.

Adult↗

PubMed2000

Human mesenchymal stem cells support megakaryocyte and pro-platelet formation from CD34(+) hematopoietic progenitor cells.

Megakaryocytopoiesis and thrombocytopoiesis result from the interactions between hematopoietic progenitor cells, humoral factors, and marrow stromal cells derived from mesenchymal stem cells (MSCs) or MSCs directly. MSCs are self-renewing marrow cells that provide progenitors for osteoblasts, adipocytes, chondrocytes, myocytes, and marrow stromal cells. MSCs are isolated from bone marrow aspirates and are expanded in adherent cell culture using an optimized media preparation. Culture-expanded human MSCs (hMSCs) express a variety of hematopoietic cytokines and growth factors and maintain long-term culture-initiating cells in long-term marrow culture with CD34(+) hematopoietic progenitor cells. Two lines of evidence suggest that hMSCs function in megakaryocyte development. First, hMSCs express messenger RNA for thrombopoietin, a primary regulator for megakaryocytopoiesis and thrombocytopoiesis. Second, adherent hMSC colonies in primary culture are often associated with hematopoietic cell clusters containing CD41(+) megakaryocytes. The physical association between hMSCs and megakaryocytes in marrow was confirmed by experiments in which hMSCs were copurified by immunoselection using an anti-CD41 antibody. To determine whether hMSCs can support megakaryocyte and platelet formation in vitro, we established a coculture system of hMSCs and CD34(+) cells in serum-free media without exogenous cytokines. These cocultures produced clusters of hematopoietic cells atop adherent MSCs. After 7 days, CD41(+) megakaryocyte clusters and pro-platelet networks were observed with pro-platelets increasing in the next 2 weeks. CD41(+) platelets were found in culture medium and expressed CD62P after thrombin treatment. These results suggest that MSCs residing within the megakaryocytic microenvironment in bone marrow provide key signals to stimulate megakaryocyte and platelet production from CD34(+) hematopoietic cells.

Antigens, CD↗

PubMed2000

Interventions for emergency contraception.

OBJECTIVES: To determine which emergency contraceptive method following unprotected intercourse is the most effective, safe and convenient for use in preventing pregnancy. SEARCH STRATEGY: The search strategy included electronic searches of the Cochrane Controlled Trials Register, Popline, Chinese biomedical databases and HRP emergency contraception database. In addition, references of retrieved papers were searched and researchers in the field and two pharmaceutical companies were contacted. SELECTION CRITERIA: Randomized or quasi-randomized studies including women attending services for emergency contraception following a single act of unprotected intercourse were eligible. DATA COLLECTION AND ANALYSIS: Data on outcomes and trial characteristics were extracted in duplicate by two reviewers. Results were expressed as relative risk using a fixed-effects model with 95 % confidence interval. MAIN RESULTS: Fifteen trials were included in the review. The majority (8/15) of the trials were conducted in China. Most comparisons between different interventions included one or two trials although some trials were appropriately sized with power calculations. Levonorgestrel appears to be more effective than Yuzpe regimen (2 trials, RR: 0.51, 95 % CI: 0.31-0.84) and causes less side-effects (RR: 0.80, 95 % CI: 0.76 to 0.84). Levonorgestrel was less effective than locally manufactured mifepristone in a single, large Chinese study (RR: 2.17, 95 % CI: 1.00 to 4.77). Effectiveness of different doses of mifepristone seem to be similar but the frequency of delay in onset of the subsequent menstrual period increases with increased dose. REVIEWER'S CONCLUSIONS: Levonorgestrel and mifepristone seem to offer the highest efficacy with an acceptable side-effect profile. One disadvantage of mifepristone is that it causes delays in onset of subsequent menses which may induce anxiety. However, this seems to be dose-related and low doses of mifepristone minimise this side-effect without compromising effectiveness. Future studies should compare the effectiveness of mifepristone with levonorgestrel.

Contraceptives, Postcoital↗

PubMed2000

Morphological study of the regeneration mechanism of acetic acid-injured colon crypts in the rat.

The regeneration mechanism of injured rat colonic mucosa with 1% acetic acid was certified in this study. The injured colons were studied periodically on experimental days 1, 3, 5, 7, 15, and 20 with light and scanning electron microscopy. Specimens were examined in paraffin sections stained with hematoxylin and eosin; crypts were isolated with the HCl digestion method; and three-dimensional stromal collagen tissue was prepared with the NaOH cell maceration method. Damage to the mucosal and submucosal layers peaked between the 1st and 3rd days with edema, regeneration, necrosis, and inflammation. The edema and inflammation subsided, and mucosal atrophy and crypt reduction remained at around 1 week. At 2 weeks the mucosa became thick, and crypts showed many branches in their lower two-thirds; and by 3 weeks the mucosa had recovered to almost normal. The ratio of number of crypts at the base and surface was almost 1.5 on the 15th day and 1.0 on the 20th day, suggesting that each branch progresses upward to create an independent crypt. We believe that the fission mechanism plays an important role in crypt repair after acetic acid injury of the colonic mucosa. As the proliferative zone of the colonic crypt is localized at the crypt base, fission of the crypt starting at the base and progressing up to the surface is the most reasonable and efficient mechanism for repair by increasing the number of crypts.

Acetic Acid↗

PubMed2000

Systemic toxicity of topical and periocular corticosteroid therapy in an 11-year-old male with posterior uveitis.

PURPOSE: To report a case of systemic corticosteroid toxicity resulting from topical and periocular therapy. METHODS: Treatment and follow-up of an 11-year-old male with uveitis are illustrated. Initial presentation of the patient was bilateral iridocyclitis, for which he was treated with prednisolone acetate 1% every 2 hours for 6 months. Subsequently, posterior uveitis developed, necessitating posterior subtenon injections. RESULTS: After initial topical corticosteroid therapy, the patient developed a cushingoid habitus accompanied by increased lanugo hair, acanthosis nigricans, posterior subcapsular lens opacities, and increased intraocular pressure. Cushingoid stigmata worsened after administration of posterior subtenon injection of corticosteroids. The patient's truncal obesity worsened, and his linear growth stopped. CONCLUSIONS: Systemic toxic effects may develop as a result of topical and local use of ophthalmic corticosteroid preparations in susceptible patients.

Acanthosis Nigricans↗

PubMed2000

Transurethral hot-water balloon thermoablation for benign prostatic hyperplasia: patient tolerance and pathologic findings.

OBJECTIVES: To determine the patient tolerance and thermal ablation pattern in human prostatic tissue after treatment with a hot water, catheter-based system. METHODS: Twenty-seven men scheduled for surgery for symptomatic benign prostatic hyperplasia or adenocarcinoma of the prostate underwent water-induced thermotherapy. The patients were randomly assigned to one of four treatment groups. Lidocaine gel was the sole means of pain control. The patients and an observer recorded patient discomfort during therapy. A Foley catheter was left in place until surgery (n = 13) or successful voiding (n = 14). Prostates were subsequently enucleated or removed, whole mounted, and examined. RESULTS: Patients reported mild treatment discomfort, the level of which did not correlate with the extent of necrosis, balloon diameter, or water temperature (all P >0. 05). Distal penile burning was the most commonly reported discomfort. All 14 patients successfully voided within 12 days of treatment. Prostates were enucleated (n = 24) or removed (n = 3) at a mean of 27 days (range 4 to 120) after thermotherapy, except for a single adenectomy 17 months after therapy. Pathologic findings included periurethral hemorrhagic necrosis, with focal or extensive urothelial denudation and mild inflammation. The mean maximal depth of necrosis from the urethral lumen was 7, 9, 10.33, and 11 mm in groups 1, 2, 3, and 4, respectively. The extent of necrosis was similar in all groups (P = 0.11), regardless of the water temperature; conversely, the balloon diameter correlated with the depth of necrosis (P = 0.024). CONCLUSIONS: This system of tissue ablation appears to be well tolerated, and it produced consistent pathologic results.

Adenocarcinoma↗

PubMed2000

Predicting extravesical extension of bladder carcinoma: a novel method based on micrometer measurement of the depth of invasion in transurethral resection specimens.

OBJECTIVES: Patients with bladder cancer and extravesical extension (Stage T3 or greater) have worse survival than those with organ-confined cancer. We sought to determine whether the depth of invasion in transurethral resection of the bladder (TURB) specimens will predict extravesical extension in patients treated by radical cystectomy. METHODS: We studied 90 patients diagnosed with invasive bladder carcinoma between 1979 and 1984. The 1997 TNM (tumor, lymph node, metastasis) system was used for pathologic staging. The mean patient age was 65 years (range 44 to 78). The male/female ratio was 5:1. All patients had invasive bladder cancer at TURB. Muscle invasion was identified in 35 patients (39%) and lamina propria invasion was present in 55 patients (61%) in the TURB specimens. The depth of invasion in the TURB specimens was measured by an ocular micrometer. All patients were treated by radical cystectomy. The median interval from TURB to cystectomy was 44 days (range 2 to 159). Extravesical extension (Stage T3 or greater) at cystectomy was present in 39 patients (43%). RESULTS: The depth of invasion was associated with final pathologic stage (Spearman correlation r = 0. 58, P <0.001). The overall accuracy of the depth of invasion for the prediction of extravesical extension, measured by the area under the receiver operating characteristic curve, was 0.81 (standard error 0. 045). The mean depth of invasion among patients with extravesical extension at cystectomy was 4.0 mm compared with 2.2 mm for those without extravesical extension. On the basis of a 4.0-mm cutoff point, the sensitivity, specificity, positive predictive value, and negative predictive value for extravesical extension were 54%, 90%, 81%, and 72%, respectively. CONCLUSIONS: Patients with a bladder cancer depth of invasion greater than 4 mm in the TURB specimens, as measured by micrometer, are likely to have extravesical extension, and more aggressive treatment should be considered.

Adult↗

PubMed2000

Prevalence, correlates, and natural history of epiretinal membranes surrounding idiopathic macular holes. Virectomy for Macular Hole Study Group.

OBJECTIVE: To report on the prevalence, correlates, and natural history of epiretinal membranes (ERM) in eyes with stage II or III/IV macular holes. DESIGN: A subgroup analysis arising from a multicentered, controlled, randomized clinical trial. SETTING: Community and university-based ophthalmology clinics. PATIENTS: Two hundred twenty four eyes with stage II or III/IV macular holes. INTERVENTIONS: No intervention for 100 eyes randomly assigned to observation. OUTCOME MEASURES: Grade of ERM determined by stereoscopic examination of fundus photographs at baseline and at 3, 6, 12, and 24 months of follow-up. RESULTS: The prevalence of ERM was 65% (145 of 224 eyes), was greater in pseudophakic than in phakic eyes (80% vs. 63%, P = 0.10), and increased with increasing severity of the hole (P < 0.0001). Stage III/IV eyes with ERM had a significantly larger hole size than did eyes without ERM (P < 0.01); however, no association between presence of ERM and visual acuity was found (P > 0.5). In the 100 phakic eyes that were randomly assigned to observation, there was a significant increase in the severity of ERM over follow-up (P < 0.0001). CONCLUSIONS: ERM are common in eyes with full-thickness idiopathic macular holes. Although ERM prevalence increases with severity and size of the macular hole, the presence of ERM are not closely correlated with visual acuity. These factors may be important in considering the removal of ERM during vitrectomy for macular hole.

California↗

PubMed2000

Evidence that axon-derived neuregulin promotes oligodendrocyte survival in the developing rat optic nerve.

It was previously shown that newly formed oligodendrocytes depend on axons for their survival, but the nature of the axon-derived survival signal(s) remained unknown. We show here that neuregulin (NRG) supports the survival of purified oligodendrocytes and aged oligodendrocyte precursor cells (OPCs) but not of young OPCs. We demonstrate that axons promote the survival of purified oligodendrocytes and that this effect is inhibited if NRG is neutralized. In the developing rat optic nerve, we provide evidence that delivery of NRG decreases both normal oligodendrocyte death and the extra oligodendrocyte death induced by nerve transection, whereas neutralization of endogenous NRG increases the normal death. These results suggest that NRG is an axon-associated survival signal for developing oligodendrocytes.

Animals↗

PubMed2000

DNA repair capacity in healthy medical students during and after exam stress.

There has been extensive research into the effects of stress on immune function but little on the effects of stress on DNA repair capacity (DRC), a process central to maintaining a normal cell cycle. Defective DRC is one of the factors responsible for carcinogenesis. In the present study we assessed DRC in healthy medical students during times of high and low stress. Sixteen medical students were evaluated during the third day of a 5-day exam period and then again 3 weeks later, after vacation. At both time points, participants underwent a brief physical examination, had venous blood drawn, and completed questionnaires to identify subjective stress levels. The DRC was assessed by the host-cell reaction assay, which measures nucleotide excision repair capacity. Participants reported significantly higher levels of subjective stress during the exam period than after vacation. DRC was also significantly higher during the exam period than after vacation, suggesting a positive association between subject stress levels and DRC. The results are discussed in relation to previous findings and implications for cancer research.

Adult↗

PubMed2000

Extranodal extension in lymph node-positive prostate cancer.

Evaluation of extranodal tumor extension may provide prognostic information for patients with epithelial malignancies. However, its importance for the patient who has prostate cancer with regional lymph node metastasis requires further investigation and clarification. This study was performed to evaluate the prognostic significance of extranodal extension (ENE) in a large series of node-positive patients. The study group included 212 node-positive patients who were treated by bilateral pelvic lymphadenectomy, radical retropubic prostatectomy, and androgen deprivation between 1987 and 1992 at the Mayo Clinic. ENE was defined as cancer perforating through the lymph node capsule into perinodal tissue. Nodal cancer volume was measured by the grid method. Univariate and multivariate risk ratios (RR) for distant metastasis-free and cancer-specific survival were estimated using the Cox proportional model. The mean follow-up was 6.3 years (median, 6.1 years). Distant metastasis-free and cancer-specific survival at 5 years for all patients was 91% and 95%, respectively. ENE was found in 126 of 212 patients (59%). The presence of ENE was not significantly associated with distant metastasis-free (RR = 1.6; 95% confidence interval [CI], 0.7 to 3.9) or cancer-specific survival (RR = 2.2; 95% CI, 0.7 to 6.8). Among 98 patients with a single positive node, there was no significant difference in distant metastasis or cancer-specific survival according to the presence of ENE (P = .88 and P = .36, respectively). After adjusting for Gleason score, DNA ploidy, and ENE, only nodal cancer volume was significantly associated with adverse distant metastasis-free (RR = 1.9; 95% CI, 1.5 to 2.8) and cancer-specific survival (RR = 1.4; 95% CI, 1.1 to 1.9). Our data indicate that the presence of ENE is not associated with unfavorable survival in patients with node-positive prostate cancer treated by radical retropubic prostatectomy, bilateral pelvic lymphadenectomy, and androgen deprivation therapy. In contrast, nodal cancer volume was predictive of distant metastasis-free survival and cancer-specific survival.

Adenocarcinoma↗

PubMed2000

The A5.1 allele of the major histocompatibility complex class I chain-related gene A is associated with psoriasis vulgaris in Chinese.

BACKGROUND: Recent studies have demonstrated an association of a polymorphic (GCT)n triplet repeat in the transmembrane (TM) region of the major histocompatibility complex (MHC) class I chain-related gene A (MICA), one of the MHC class I chain-related (MIC) family members, with some autoimmune diseases, including Behçet's disease, acute anterior uveitis, Takayasu's arteritis and others. OBJECTIVES: The aim of this study was to examine whether the MICA gene is associated with psoriasis vulgaris (PS) in Chinese. PATIENTS AND METHODS: The (GCT)n polymorphism of the MICA gene was investigated in 200 healthy Chinese of Han origin and 300 patients with PS by polymerase chain reaction amplification and denaturing polyacrylamide gel electrophoresis. RESULTS: Five alleles, namely A4, A5, A6, A9 and A5.1 were found in both groups. Comparison of the data from both groups revealed that the A5.1 allele was present at a significantly higher frequency in the patient group (41.5%) than in the control group (23.0%) (Pc < 0.0001, Pc means the probability of a comparison with the control group). The frequency of A5.1-positive cases was also significantly increased in the patient group (68.0%) as compared with the controls (38.0%) (Pc < 0.0001). Furthermore, the carrier frequency of A5.1-positive was significantly increased in psoriatic patients with a positive family history and with early onset as compared with sporadic cases (Pc = 0.0005) and with late onset PS (Pc = 0.002). CONCLUSIONS: These results suggest that the MICA gene may be associated with the development of PS in Chinese.

Adolescent↗

PubMed2000

10q23.3 loss of heterozygosity is higher in lymph node-positive (pT2-3,N+) versus lymph node-negative (pT2-3,N0) prostate cancer.

Loss of heterozygosity (LOH) in the region of 10q23.3 has been associated with multiple tumors, including glioblastoma multiforme, melanoma, endometrial carcinoma, and prostate carcinoma. The tumor suppressor gene, PTEN/MMAC1, is also located in this region, and, in addition to other tumor types (eg, glioblastoma multiforme, endometrial, and melanoma), PTEN/MMAC1 mutations have been found in prostate cancer cell lines, xenografts, and hormone refractory prostate cancer tissue specimens. The aim of this study was to evaluate LOH at 10q23.3 as a marker of cancer progression in node-positive prostate cancer. Genetic alterations in the region of 10q23.3 were assessed in 23 node-positive (pT2-3, N+) and 44 node-negative prostate (pT2-3, N0) cancers with D10S532, D10S1687, D10S541, and D10S583 flanking polymorphic genetic markers; PTENCA, a genetic marker within PTEN/MMAC1, was also tested. Using DNA from paired normal and microdissected tumor samples, LOH at microsatellite loci was determined after polymerase chain reaction amplification. LOH in at least 1 marker was identified in 14% (6 of 44) of lymph node-negative and 43% (10 of 23) of lymph node-positive prostate cancers (chi-square test, P = .007). This increase in genetic alterations in node-positive prostate cancer suggests that 10q23.3 is a marker for metastatic progression.

Adenocarcinoma↗

PubMed2000

Cyclooxygenase-2 expression in human pancreatic adenocarcinomas.

Cyclooxygenase-2 (COX-2) expression is up-regulated in several types of human cancers and has also been directly linked to carcinogenesis. To investigate the role of COX-2 in pancreatic cancer, we evaluated COX-2 protein expression in primary human pancreatic adenocarcinomas (n = 23) and matched normal adjacent tissue (n = 11) by immunoblot analysis. COX-2 expression was found to be significantly elevated in the pancreatic tumor specimens compared with normal pancreatic tissue. To examine whether the elevated levels of COX-2 protein observed in pancreatic tumors correlated with the presence of oncogenic K-ras, we determined the K-ras mutation status in a subset of the tumors and corresponding normal tissues. The presence of oncogenic K-ras did not correlate with the level of COX-2 protein expressed in the pancreatic adenocarcinomas analyzed. These observations were also confirmed in a panel of human pancreatic tumor cell lines. Furthermore, in the pancreatic tumor cell line expressing the highest level of COX-2 (BxPC-3), COX-2 expression was demonstrated to be independent of Erk1/2 activation. The lack of correlation between COX-2 and oncogenic K-ras expression suggests that Ras activation may not be sufficient to induce COX-2 expression in pancreatic tumor cells and that the aberrant activation of signaling pathways other than Ras may be required for up-regulating COX-2 expression. We also report that the COX inhibitors sulindac, indomethacin and NS-398 inhibit cell growth in both COX-2-positive (BxPC-3) and COX-2-negative (PaCa-2) pancreatic tumor cell lines. However, suppression of cell growth by indomethacin and NS-398 was significantly greater in the BxPC-3 cell line compared with the PaCa-2 cell line (P = 0.004 and P < 0.001, respectively). In addition, the three COX inhibitors reduce prostaglandin E(2) levels in the BxPC-3 cell line. Taken together, our data suggest that COX-2 may play an important role in pancreatic tumorigenesis and therefore be a promising chemotherapeutic target for the treatment of pancreatic cancer.

Adenocarcinoma↗

PubMed2000

Potential impact of hormonal male contraception: cross-cultural implications for development of novel preparations.

The prospect of a hormonal male contraceptive is no longer distant. Data on the potential impact of this improvement in contraceptive provision, however, is limited, particularly between different cultures. We have therefore carried out a multi-centre study to assess men's attitudes to proposed novel hormonal methods. Questionnaire-based structured interviews were administered to men in Edinburgh, Cape Town, Shanghai and Hong Kong. Approximately 450 men were interviewed in Edinburgh, Shanghai and Hong Kong, and a slightly larger group (n = 493) in Cape Town to give samples (n > 150) of black, coloured and white men. Knowledge of existing male and female methods of contraception was high in all centres and groups. The majority of men welcomed a new hormonal method of contraception, 44-83% stating that they would use a male contraceptive pill. Overall, a pill was more acceptable than an injectable form (most popularly given at 3-6 month intervals); long-acting implants were least so except in Shanghai. Familiarity with comparable female methods appeared to influence acceptability, for both oral and injectable methods. Hong Kong was the only centre where a male method (condom) was currently the most commonly used; men there appeared to rate the convenience of condoms highly while being least likely to think that they provided effective protection against pregnancy compared to other centres, and were least enthusiastic about novel male methods. The acceptability of potential male hormonal methods of contraception was high in some groups but showed wide variability, determining factors including cultural background and current contraceptive usage. These results suggest that the emerging emphasis that men should have greater involvement in family planning will be substantiated when appropriate contraceptive methods become available.

Adolescent↗

PubMed2000

Would women trust their partners to use a male pill?

Despite a renewed interest in the development of hormonal contraceptives for men, many discussions about the potential acceptability of a 'male pill' end by speculating whether women would trust their partners to use the method reliably. To determine the views of women, we undertook a survey of 1894 women attending family planning clinics in Scotland (450), China (900) and South Africa (544). In all centres over 65% of women thought that the responsibility for contraception falls too much on women. More than 90% in South Africa and Scotland thought that a 'male pill' was a good idea, with Chinese women (71% in Hong Kong and 87% in Shanghai) only slightly less positive. Only 13% of the total sample did not think that hormonal male contraception was a good idea and only 36 women (2% of the total) said that they would not trust their partner to use it. 78% of Scottish women, 71% of Shanghai women, and 78% of white women and 40% of black and coloured women in Cape Town thought that they would use the method. This survey should dispel the myth that women would not trust their partners to use a 'male pill' reliably and illustrates the potential market for the method.

Adolescent↗