In vitro initial expansion of mesenchymal stem cells is influenced by the culture parameters used in the isolation process

In the last years, there were many studies based on the use of human bone marrow mesenchymal stem cells (hMSCs) in cell therapy and tissue engineering. Although hMSCs can be easily obtained and expanded in culture, a large number of cells are often needed. The expansion of hMSCs depends on the culture conditions, such as media, cell density or culture flasks. Moreover, growth factors are often added to improve cell proliferation. In this study, we compared the effect of two culture media (DMEM and alpha-MEM), two culture flasks (75 or 25 cm2) and two different mononuclear cell seeding densities (1 x 10(4) or 5 x 10(4) MNC/cm2) on the isolation of hMSCs from bone marrow samples and analyzed if the isolation conditions affected the expansion of these cells in the first two passages. Experiments were performed without the addition of exogenous growth factors. Our results showed that alpha-MEM is the optimal culture medium for both, isolation and expansion of mesenchymal stem cells. Moreover, the cell seeding density of 50,000 MNC/cm2 in 25 cm2 culture flasks seems to be the best condition for the isolation step.

Molecular analysis of HLA-DRB1 allelic associations with systemic lupus erythematous and lupus nephritis in Taiwan

To evaluate the association of human leukocyte antigen (HLA)–DRB1 alleles with systemic lupus erythematosus (SLE) and lupus nephritis (LN) in the Taiwanese population, and to investigate the possible association of HLA-DRB1 alleles with disease severity in LN. HLA-DRB1 alleles were studied in 105 SLE patients (82 patients with LN, 23 patients without LN) and 855 healthy controls by polymerase chain reaction and sequence-based typing assays. The frequency of the HLA class II alleles DRB1*0301 (Odds ratio [OR] = 2.01, 95% confidence interval [CI] = 1.31–3.10, Pc = 0.02) and DRB1*1501 (OR = 2.06, 95% CI = 1.36–3.13, Pc = 0.01) were both increased in SLE patients, compared to healthy controls. The frequency of DRB1*1202 was significantly lower in LN patients than in SLE patients without nephritis (OR = 0.23, 95% CI = 0.09–0.57, Pc = 0.01). No specific allele was significantly associated with an increased or decreased risk for severity of LN in this sample. In Taiwanese people, the DRB1*0301 and DRB1*1501 alleles are significant risk factors for SLE, while the DRB1*1202 allele is protective for LN.

Low-dose nesiritide in human anterior myocardial infarction suppresses aldosterone and preserves ventricular function and structure: a proof of concept study

BACKGROUND

B-type natriuretic peptide (BNP, nesiritide) has anti-fibrotic, anti-hypertrophic, anti-inflammatory, vasodilating, lusitropic and aldosterone-inhibiting properties but conventional doses of BNP cause hypotension, limiting its use in heart failure.

OBJECTIVE

To determine whether infusion of low-dose BNP within 24 h of successful reperfusion for anterior acute myocardial infarction (AMI) would prevent adverse left ventricular (LV) remodelling and suppress aldosterone.

METHODS

A translational proof-of-concept study was carried out to determine tolerability and biological activity of intravenous BNP at 0.003 and 0.006 microg/kg/min, without bolus started within 24 h of successful reperfusion for anterior AMI. 24 patients with first anterior wall ST elevation AMI and successful revascularisation were randomly assigned to receive 0.003 (n = 12) or 0.006 (n = 12) microg/kg/min of IV BNP for 72 h in addition to standard care during hospitalisation for anterior AMI.

RESULTS

Baseline characteristics, drugs and peak cardiac biomarkers for myocardial damage were similar between both groups. Infusion of BNP at 0.006 microg/kg/min resulted in greater biological activity than infusion at 0.003 microg/kg/min as measured by higher mean (SEM) plasma cGMP levels (8.6 (1) vs 5.5 (1) pmol/ml, p<0.05) and suppression of plasma aldosterone (8.0 (2) to 4.6 (1) ng/dl, p<0.05), which was not seen in the 0.003 microg/kg/min group. LV ejection fraction (LVEF) improved significantly from baseline to 1 month (40 (4)% to 54 (5)%, p<0.05) in the 0.006 group but not in the 0.003 group. Infusion of BNP at 0.006 microg/kg/min was associated with a decrease of LV end-systolic volume index (61 (9) to 43 (8) ml/m(2), p<0.05) at 1 month, which was not seen in the 0.003 group. No drug-related serious adverse events occurred in either group.

CONCLUSIONS

72 h infusion of low BNP at the time of anterior AMI is well tolerated and biologically active. Patients treated with low-dose BNP had improved LVEF and smaller LV end-systolic volume at 1 month.

Temporal knowledge representation and reasoning techniques using time Petri nets

In this paper, we present temporal knowledge representation and reasoning techniques using time Petri nets. A method is also proposed to check the consistency of the temporal knowledge. The proposed method can overcome the drawback of the one presented in Yao (1994). It provides a useful way to check the consistency of the temporal knowledge.

Seroprevalence and risk factors for human papillomavirus in Taiwan

The aim of the study was to tailor a future Human papillomavirus (HPV) vaccine campaign and to help perform early primary prevention of HPV infection in Taiwan, where the incidence of cervical cancer is high. A cross-sectional survey was conducted of 826 female students, ages 10, 13, 16 and 19-22 years. A self-administered questionnaire was used to collect information on risk factors for HPV infection. Serum samples were tested for antibodies to HPV 16 capsids using a virus-like particle-based enzyme-linked immunosorbence assay. The age-adjusted odds ratio of HPV seropositivity was calculated for each risk factor by multiple logistic regression analysis. HPV 16 antibodies were detected in 13 (1.6%) of 826 participants. The HPV 16 seroprevalence was 0.35% (1/287), 0.85% (2/235), 3.2% (6/185) and 3.4% (4/119), respectively, for age groups of 10, 13, 16 and 19-22 years. In the multiple regression analysis, the history of having sexual activity was the most significant risk predictor for HPV 16 seropositivity. The seroprevalence of HPV 16 increased dramatically among high school seniors and university students, and was significantly associated with sexual activity. Vaccination against HPV is suggested to be undertaken in early adolescence, before 16 years of age and prior to sexual debut.

Ertapenem for the treatment of extended-spectrum β-lactamase-producing Gram-negative bacterial infections

Ertapenem is indicated for complicated intra-abdominal, skin and skin-structure, urinary tract and acute pelvic infections as well as community-acquired pneumonia, for which there are cheaper and more narrow-spectrum antibiotics. It is active against extended-spectrum beta-lactamase (ESBL)-producing Gram-negative bacteria, but report of its clinical efficacy is lacking. We evaluated our experience with the use of ertapenem for ESBL-producing Gram-negative bacterial infections over 13 months. Forty-seven patients were treated with 50 courses of ertapenem. Thirty-nine courses were for ESBL-producing Gram-negative bacterial infections, 33% of which were bacteraemia. The clinical response rate was 92% and survival to hospital discharge was 94%. We propose that ertapenem has a role in the first-line treatment of these infections.

PCR tools for the verification of the specific identity of ascaridoid nematodes from dogs and cats

Based on the sequences of the internal transcribed spacers (ITS-1 and ITS-2) of nuclear ribosomal DNA (rDNA) of Toxocara canis, Toxocara cati, Toxocara malaysiensis and Toxascaris leonina, specific forward primers were designed in the ITS-1 or ITS-2 for each of the four ascaridoid species of dogs and cats. These primers were used individually together with a conserved primer in the large subunit of rDNA to amplify partial ITS-1 and/or ITS-2 of rDNA from 107 DNA samples from ascaridoids from dogs and cats in China, Australia, Malaysia, England and the Netherlands. This approach allowed their specific identification, with no amplicons being amplified from heterogeneous DNA samples, and sequencing confirmed the identity of the sequences amplified. The minimum amounts of DNA detectable using the PCR assays were 0.13-0.54ng. These PCR assays should provide useful tools for the diagnosis and molecular epidemiological investigations of toxocariasis in humans and animals.

Identification of anisakid nematodes with zoonotic potential from Europe and China by single-strand conformation polymorphism analysis of nuclear ribosomal DNA

Using genetic markers defined previously in the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA), isotopic, and non-isotopic polymerase-chain-reaction-coupled single-strand conformation polymorphism (SSCP) were utilized to identify each of three anisakid species [Anisakis simplex (s.l.), Contracaecum osculatum (s.l.), and Hysterothylacium aduncum] from different host species and geographical locations in Poland and Sweden. While subtle microheterogeneity was observed within each of Anisakis simplex (s.l.) and H. aduncum, distinct SSCP profiles were displayed for each of the three species, allowing identification and differentiation of the three taxa. Subsequent sequencing of the ITS-1 and ITS-2 rDNA revealed that A. simplex (s.l.) represented Anisakis simplex s.s. and Contracaecum osculatum (s.l.) represented C. osculatum C. Application of the non-isotopic SSCP assay of ITS-2 to larval anisakid samples from different hosts and geographical locations in China revealed three distinct SSCP profiles, one of which was consistent with that of A. simplex (s.l.), and the other two had different SSCP profiles from that of C. osculatum C and H. aduncum. Sequencing of the ITS-1 and ITS-2 rDNA for representative Chinese anisakid samples examined revealed three anisakid species in China, i.e., Anisakis typica, Anisakis pegreffii, and Hysterothylacium sp. These molecular tools will be useful for identification and investigation of the ecology of anisakid nematodes in China and elsewhere.

Postoperative Programmed Muscle Tension Augmented Osteotendinous Junction Repair

The postoperative programmed muscle tension induced by functional electrical stimulation (FES) was evaluated for its potential efficacy on acceleration of osteotendinous junction healing using an established partial patellectomy model in rabbits. After immobilization of the operated knee for 6 weeks, daily FES was applied to quadriceps muscles for 30 minutes per day and 5 days per week for 6 weeks in the treatment group and compared with the non-treatment control group at postoperative week 12 and 18, radiologically, histologically and biomechanically. Results showed that FES-induced muscle tension significantly increased new bone formation, bone mineral density, and fibrocartilage zone restoration in the osteotendinous healing interface. The failure load and ultimate strength of the repairing osteotendinous complex were also improved significantly with healing over time. In conclusion, the postoperative programmed FES-induced muscle tension was favorable for acceleration of osteotendinous junction repair and therefore recommended for clinical trails in orthopedic sports medicine and rehabilitation.

The rubella virus nonstructural protease recognizes itself via an internal sequence present upstream of the cleavage site for trans-activity

The substrate requirement for rubella virus protease trans-activity is unknown. Here, we analyzed the cleavability of RV P200-derived substrates varying in their N-terminal lengths (72–475 amino acids) from the cleavage site by the RV protease trans-activity. Only substrates with at least 309 amino acid residues N-terminal to the cleavage site were able to undergo cleavage. Further, rubella sequence was found to be necessary in the N-terminal region of the substrate, whereas a heterologous sequence C-terminal to the cleavage site was tolerated. These results demonstrated a requirement for residues located between amino acids 994–1102 of the RV P200 polyprotein, besides its cleavage site for RV protease trans-activity. This region overlaps with the starting site of the essential cis-protease activity of RV P200 polyprotein. This is a novel observation for a viral protease of the family Togaviridae.

Membrane bioreactor application in wastewater re-use from the effluent of Bali primary WWTP, northern Taiwan

Two MBR pilot systems were constructed and tested in the Bali Primary WWTP. The pilot study shows that two MBR systems, i.e. the Green-MenBio system (MBR-1) and the Bio-MF system (MBR-2), can both fulfill the requirement of wastewater reclamation standard. The MBR-2 system is more economical compared with MBR-1 system. The cost of US dollars 0.10-0.16/m3 is estimated to reclaim the effluent of primary WWTP in Taiwan. The Bali Primary WWTP has the capacity of 1,320,000 cmd which is the biggest in Taiwan. The domestic wastewater of partial Taipei City and Taipei County are collected and transported to the Bali Primary WWTP. The effluent of the Bali Primary WWTP is then discharged into the ocean through two 3.8 m marine outfalls. The AO processes are installed in both MBR systems. More than 90% of the NH3-N can be removed through the AO and membrane processes. The outflow of the MBR systems (without RO) can reach the quality of COD <30 mg/l, BOD <10 mg/l, SS <5 mg/l, NH3-N <3 mg/L. The outflow of the MBR system is proposed to transport 40 km south to the Taoyuan County where four new industrial parks are to be constructed. Part of the reclaimed water is to be used on irrigation and another portion is to be sent to the industries after RO treatment.

Linking watershed and eutrophication modelling for the Shihmen Reservoir, Taiwan

The Shihmen Reservoir, located in northern Taiwan, features the second storage volume of impoundments on the island. The watershed of the Shihmen Reservoir has been subjected to serious pollutants due to anthropogenic interference. This study applies a watershed model, BASINS, to simulate the flow and nutrients loads from the watershed. BASINS then drives the CE-QUAL-W2 model for water quality predictions in the reservoir. The watershed modelling results are compared with field data. They reveal that significant nutrient loads were generated from the watershed during storms. The model calibration and verification were achieved with water surface elevation, temperature, and water quality constituents including nutrients, dissolved oxygen, and chlorophyll a in the reservoir using the eutrophication model.

Cycloheximide enhances maintenance of methamphetamine-induced conditioned place preference

Accrued evidence demonstrated the necessity of protein synthesis at acquisition, consolidation and expression stages in conditioning/learning tasks, while the underlying mechanisms of the maintenance of memory remained less explored. This study was designed to characterize the maintenance of methamphetamine-induced conditioned place preference, a drug-induced learning and memory. In addition, cycloheximide, a protein synthesis inhibitor, was used to examine the involvement of protein synthesis in the maintenance of such place preference memory. We found that the maintenance of the rapidly-established methamphetamine (2 mg/kg, i.p.) -induced conditioned place preference could be long-lasting and even over fifty days under the present protocol of extinction. Moreover, it was of interest to note the undulating expression of this conditioned place preference throughout the extinction protocol. Most importantly, as the methamphetamine-induced conditioned place preference was acquired and expressed by mice, the saline-pretreated control mice underwent numbers of intermittent extinction across a long-term retention test period, while cycloheximide-pretreated mice exhibited unaltered methamphetamine-induced conditioned place preference throughout the same retention test period. Taken together, we conclude that [1] methamphetamine-induced conditioned place preference could last for a long period of time, and such place preference memory is reluctant to extinguish even animals' repeated exposure to the previous conditioned environment at a drug-free status, and [2] blockade of protein synthesis may enhance the maintenance of the methamphetamine-induced conditioned place preference.

Methamphetamine-induced conditioned place preference is facilitated by estradiol pretreatment in female mice

Ovarian hormones were well documented to modulate the dopamine release in the central dopaminergic systems. The dopamine-releasing effects in the nucleus accumbens, a major target of the mesolimbicortical dopaminergic system, were closely associated with the reinforcing effects of two psychomotor stimulants, cocaine and methamphetamine. This study aimed to examine the sex differences in the cocaine- and methamphetamine-reinforcing behavior, conditioned place preference. In addition, the modulating effects of estradiol and progesterone on methamphetamine-induced conditioned place preference were investigated in both sexes of adult gonadectomized mice. There was no sex difference in the sensitivity to the cocaine (5 mg/kg)-induced conditioned place preference. However, female mice exhibited a more potent methamphetamine (1 mg/kg)-induced conditioned place preference than did male mice. Moreover, pretreatment with estradiol for two consecutive days before the beginning of the conditioning and throughout the four daily conditionings (0.47 microg/day for totally six days) effectively facilitated methamphetamine-induced conditioned place preference in gonadectomized female mice, but not in gonadectomized male mice. Progesterone, under a similar treatment regimen (0.47 microg/day for six consecutive days), did not alter the methamphetamine-induced conditioned place preference in either sex of gonadectomized mice. Taken together, we conclude that the facilitating effects of estradiol on methamphetamine-induced conditioned place preference could be sex-dependent with an eminent sensitivity associated with the adult female mice.

The Swedish Two-County Trial of mammographic screening: cluster randomisation and end point evaluation

BACKGROUND

The Swedish Two-County Trial has been criticised on the grounds of the cluster randomisation and alleged bias in classification of cause of death.

PATIENTS AND METHODS

In the Two-County Trial, 77 080 women were randomised to regular invitation to screening (active study population, ASP) and 55 985 to no invitation (passive study population, PSP), in 45 geographical clusters. After approximately 7 years, the PSP was invited to screening and the trial closed. We analysed data using hierarchical statistical models to take account of cluster randomisation, and performed a conservative analysis assuming a systematic difference between ASP and PSP in baseline breast cancer mortality in one of the counties. We also analysed deaths from causes other than breast cancer and from all causes among breast cancer cases diagnosed in the ASP and PSP.

RESULTS

Taking account of the cluster randomisation there was a significant 30% reduction in breast cancer mortality in the ASP. Conservatively, assuming a systematic difference between ASP and PSP clusters in baseline breast cancer mortality, there was a significant 27% reduction in mortality in the ASP. Ignoring classification of cause of death, there was a significant 13% reduction in all-cause mortality in breast cancer cases in the ASP.

CONCLUSIONS

Breast cancer mortality is a valid end point and mammographic screening does indeed reduce mortality from breast cancer. The criticisms of the Swedish Two-County Trial are unfounded.

Anti-leukemic immunity against U937 cells in uremic patients

To examine anti-tumor immunity in uremic patients undergoing regular hemodialysis, we designed this study using in vitro mononuclear cell (MNC) cultures, with human leukemic U937 cells as the target. MNC were collected and cultured from uremic subjects and age- and gender-matched healthy controls. Conditioned media from the cultures (MNC-CM) were collected after stimulation with various concentrations of phytohemagglutinin (PHA). The proliferation-inhibiting and differentiation-inducing activities of the PHA-MNC-CM on U937 cells were evaluated. The growth inhibition activity of uremic patients' PHA-MNC-CM was lower than that of controls. The differentiation-inducing effects were evaluated by morphological scoring, superoxide production, and monocyte-associated antigen expression (CD14 and CD68). All three parameters demonstrated that the differentiation-inducing effect of MNC-CM increased with increasing doses of PHA. These effects, however, were significantly less in uremic patients compared to controls at higher doses of PHA. The levels of TNF-alpha and IFN-gamma in PHA-MNC-CM increased in a PHA dose-dependent manner and were much higher in the controls. We conclude that the capacity of MNC from uremic hemodialysis patients to produce anti-leukemic immunity is significantly lower than that of healthy controls.

Measurement of day and night neutrino energy spectra at SNO and constraints on neutrino mixing parameters

The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.

Direct evidence for neutrino flavor transformation from neutral-current interactions in the Sudbury Neutrino Observatory

Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold of 5 MeV. The non-nu(e) component is phi(mu)(tau) = 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) x 10(6) cm(-2) s(-1), 5.3sigma greater than zero, providing strong evidence for solar nu(e) flavor transformation. The total flux measured with the NC reaction is phi(NC) = 5.09(+0.44)(-0.43)(stat)(+0.46)(-0.43)(syst) x 10(6) cm(-2) s(-1), consistent with solar models.

Functional characterization of Marek's disease virus (MDV) origin-binding protein (OBP): analysis of its origin-binding properties

In previous studies, we identified a Marek's disease virus (MDV) origin-binding protein (OBP) gene that is highly homologous to the herpes simplex virus type 1 UL9 gene that encodes an OBP and functions as an initiator protein for viral DNA replication. In this study, a protein of 95 kDa was produced in coupled in vitro transcription-translation reaction with the plasmid containing the wild type MDV OBP gene. The in vitro synthesized protein was detected by immunoprecipitation with a penta-histidine specific monoclonal antibody. Further characterization of MDV OBP was accomplished using electrophoretic mobility shift assay (EMSA) with the in vitro expressed MDV OBP using a double-stranded (ds) 26-mer oligonucleotide as the probe, which was designed from the putative MDV OBP binding site present in the serotype 1 or 2 MDV replication origin. The EMSA results indicated that MDV OBP could form a protein-DNA complex with the ds 26-mer oligonucleotide designed from serotype 1 or 2 replication origin. A series of 26-mer oligonucleotides with two-base-pair (bp) substitution across the putative MDV OBP binding site were used in competitive EMSA to determine the recognition sequence for the MDV OBP. The results demonstrated that the recognition sequence for MDV OBP was the TTCGCACC that is a subset of a 9-bp element (CGTTCGCAC) conserved in the replication origins of alphaherpesviruses. Furthermore, the results of EMSA with a series of deletion mutants from the N-terminus of MDV OBP indicated that the origin-binding domain was located at the amino acids region 528 to 841 of the wild-type MDV OBP. Taken together, our results suggest that the MDV OBP gene encodes an OBP of MDV.

Humoral response to p53 in human colorectal tumors: a prospective study of 1,209 patients

p53 Antibodies (p53-Abs) have been detected in the serum of a proportion of colorectal cancer (CRC) patients. It is not yet known at which stage during colorectal tumor progression p53-Abs appear in the serum. The utility of these antibodies as markers for CRC prognosis remains to be clarified. Using a quantitative enzyme-linked immunosorbent assay, we analyzed serum samples from 998 CRC patients and from 211 patients with polyp. Levels of p53-Abs were defined as negative (<10 U/microL), low (10-76 U/microL) and high (>76 U/microL). Overall, 13.0% of CRC patients and less than 1% of polyp patients had increased serum p53-Ab levels. High p53-Ab levels were only seen in patients with invasive carcinomas. The parameters that were significantly and independently associated with a greater frequency of high p53-Ab levels were the left colon (odds ratio [OR] = 3.4; 95% CI = 1.1-10.5), the rectum (OR = 2.9; 95% CI, 1.0-8.8) and advanced lymph node metastasis (OR = 4.6; 95% CI, 2.2-9.6). In univariate analysis, patients with high p53-Ab levels had a shorter survival times than did those without (p = 0.007). However, the significant effect disappeared in a Cox regression model adjusting for sex, age, tumor location, carcinoembryonic antigen levels, gross findings, histologic grade, mucin production and TNM stage. Thus, autoantibodies against p53 occur with tumor progression in multistep colorectal carcinogenesis and increase with advanced node metastasis. Furthermore, the seemingly adverse effect of high p53-Ab levels on the survival of CRC patients may be explained by other prognostic factors.

Associations of defecography and physiologic findings in male patients with rectocele

This study evaluated the incidence and physiological findings in male patients with rectoceles. All defecographic studies were evaluated by a single colorectal surgeon. After diagnosis of rectocele in male patients, the patient's history, symptoms, and physiologic tests (anal manometry, pudendal nerve terminal motor latency [PNTML], assessment and electromyography [EMG]) were studied. A prominent rectocele was defined as one that did not empty during defecography and was associated with outlet obstructive syndrome. Forty (17%) rectoceles were diagnosed in 234 male patients with evacuatory disorders who underwent defecography. Rectoceles were anterior in 19 (48%) and posterior in 21 (52%) patients. The main complaint was constipation with difficult defecation in 33 (83%), followed by rectal pain in 5 (13%), rectal prolapse in 1 (3%), and incontinence in 1 (3%). Previous prostatic surgery had been performed in 16 (40%) patients. The mean age and duration of symptoms were 72.4 years (range, 30-88) and 10.3 years (range, 0.5-70), respectively. Excessive straining during evacuation was noted in 73%, unilateral or bilateral pudendal neuropathy in 24.5%, paradoxical puborectalis contraction in 49% and abnormal EMG in 11% of patients. Higher resting pressures with a mean 3.9 cm high pressure zone were noted in 29% of patients. The accompanying findings in defecography were, non-relaxing or partially relaxing puborectalis muscle (66%), perineal descent (65%), intussusception (23%), and sigmoidocele (15%). None of the patients underwent surgery for rectocele alone. In conclusion, rectocele is uncommon in males; it rarely appears as an isolated dysfunction as it is often associated with functional disorders of the pelvic floor. There is a frequent association between rectocele and prostatectomy. Clinical significance and therapeutic strategy remain unknown.

Role of the natriuretic peptides in the cardiorenal and humoral actions of omapatrilat: insights from experimental heart failure

Vasopeptidase (VP) inhibitors are novel molecules that co-inhibit neutral endopeptidase 24.11 (NEP), which degrades natriuretic peptides and angiotensin-converting enzyme (ACE). We review the biology of the natriuretic peptide system and a recent study of the role for the natriuretic peptide system in the mechanism of action of omapatrilat (the most clinically advanced VP inhibitor). This study compared the cardiorenal and humoral actions of omapatrilat with those of ACE inhibition. The actions of omapatrilat were further defined in the presence and absence of a natriuretic peptide receptor antagonist. This investigation provided insight into a unique new pharmacologic agent that has beneficial renal actions in experimental mild heart failure that exceed those seen with ACE inhibition alone and that are linked to the natriuretic peptide system.

Recurrent hypertensive intracerebral hemorrhage among Taiwanese

Hypertensive intracerebral hemorrhage (HICH) was once thought to be a one-time event with very rare recurrence, but recent studies have revealed that the recurrent hemorrhage due to hypertension is not unusual. The purpose of this study was to determine the clinical characteristics of HICH among Taiwanese. From June 1988 to December 1999, 1421 HICH patients were admitted to our hospital. Among them, 68 patients (4.8%) had recurrent HICH. We reviewed their medical records and computed tomographic findings. There were 46 males and 22 females (M/F = 2.1) with a mean age of 59.9 +/- 11.9 years at the onset of the second hemorrhage. The median interval between the first two hemorrhages was 22.5 months (range: 1-107 months). Most of the recurrence was within two years of the first hemorrhage (within 1 year in 27.9%, within 1-2 years in 25%). The location of the second hemorrhage was typical for HICH (putamen in 44.1%, thalamus in 33.8%, cerebellum in 5.9%, pons in 4.4%, and caudate nucleus in 1.5%) except for 7 patients (10.3%) who had lobar hematoma. Forty-nine patients (72%) had both hemorrhages located in the supratentorium and in most of them (40 patients) the recurrent HICH occurred contralaterally to the first one. Putaminal-thalamic pattern was the most common (23.5%), followed by the putaminal-putaminal pattern (20.6%). The mortality rate of the second HICH was 17.6%. Seven patients (10.3%) experienced more than 2 episodes of hemorrhages. This report found that the recurrent HICH was not rare among Taiwanese. A substantial proportion (19.1%) of recurrence was after 5 years. The male predominance and risk factor for recurrent HICH require further study.

Estimating the benefits of adjuvant systemic therapy for women with early breast cancer

BACKGROUND

Prognostic factors are commonly used to help identify women with node-negative breast cancer at high risk of recurrence. Although many are available, knowing which risk factor or combination of factors to use to estimate prognosis for an individual woman is often difficult. This study documented the baseline prognoses for a group of women with node-negative breast cancers, and estimated the potential benefits of adjuvant systemic therapy.

METHODS

Ten-year, actuarial, cause-specific survival based on tumour size and histological grade using data from the Swedish Two-County Trial of mammographic screening was calculated for 1200 women with node-negative cancers of less than 30 mm diameter. The benefits of adjuvant systemic therapy for these women were then estimated using the published odds reductions in death from adjuvant systemic therapy from the Early Breast Cancer Trialists' Collaborative Group overview.

RESULTS

The absolute 10-year survival benefits for subgroups of women based on tumour size and histological grade were estimated for women aged under 50 years by the addition of chemotherapy, and over 50 years by the addition of tamoxifen and/or chemotherapy.

CONCLUSION

Decisions about adjuvant systemic therapy in women with node-negative breast cancer need to be individualized, taking into account treatment efficacy and toxicity. The quantitative methods presented in this paper facilitate such decisions.

The thymidylate synthase gene of Hz-1 virus: a gene captured from its lepidopteran host

The sequence analysis of a thymidylate synthase gene was identified in the Hz-1 virus HindIII-D fragment. The viral thymidylate synthase gene encodes a protein of 295 amino acids, and is closely related to that of insect, mammals and herpesvirus. The thymidylate synthase gene identified was a genuine viral gene in that it was only detected in cells infected with Hz-1 virus but not in the mock infected cells, by Southern blot analysis and by RT-PCR. Results of phylogenetic analysis based on non-synonymous and amino acid distances suggested that the TS gene of Hz-1 virus was grouped closely with that of Bombyx mori. High bootstrap values confirmed that the thymidylate synthase of Hz-1 virus was acquired by a capture event from its lepidopteran host. Results of both sequence divergences and phylogenetic analysis suggested that TS genes in insect viruses, Hz-1, CIV, and MsEPV may have a different history or originated from different capture events.