The convective instability of a Maxwell-Cattaneo fluid in the presence of a vertical magnetic field.

We study the instability of a Bénard layer subject to a vertical uniform magnetic field, in which the fluid obeys the Maxwell-Cattaneo (MC) heat flux-temperature relation. We extend the work of Bissell (Proc. R. Soc. A 472, 20160649 (doi:10.1098/rspa.2016.0649)) to non-zero values of the magnetic Prandtl number p m . With non-zero p m , the order of the dispersion relation is increased, leading to considerably richer behaviour. An asymptotic analysis at large values of the Chandrasekhar number Q confirms that the MC effect becomes important when C Q 1/2 is O(1), where C is the MC number. In this regime, we derive a scaled system that is independent of Q. When CQ 1/2 is large, the results are consistent with those derived from the governing equations in the limit of Prandtl number p → ∞ with p m finite; here we identify a new mode of instability, which is due neither to inertial nor induction effects. In the large p m regime, we show how a transition can occur between oscillatory modes of different horizontal scale. For Q ≫ 1 and small values of p, we show that the critical Rayleigh number is non-monotonic in p provided that C > 1/6. While the analysis of this paper is performed for stress-free boundaries, it can be shown that other types of mechanical boundary conditions give the same leading-order results.

Morbidity associated with the immediate vertical rectus abdominus myocutaneous flap reconstruction after radical pelvic surgery.

AIM: Patients who undergo radical pelvic surgery often have problems with perineal wound healing and pelvic collections. While there is recognition of the perineal morbidity, there also remains uncertainty around the benefit of vertical rectus abdominus myocutaneous (VRAM) flaps due to the balance between primary healing and the complications associated with this form of reconstruction. This study aimed to evaluate factors associated with significant flap and donor site related complications following VRAM flap reconstruction for radical pelvic surgery. METHOD: A retrospective analysis of VRAM flap related complications was undertaken from prospectively maintained databases for all patients undergoing radical pelvic surgery (2001- 2017) in two cancer centres. RESULTS: In all, 154 patients were identified [median age 62 years (range 26-89 years), 80 (52%) men]. Thirty-three (21%) patients experienced significant donor or flap related complications. Major complications (Clavien-Dindo ≥ 3) related to the abdominal donor site occurred in nine (6%) patients, while those related to the flap or perineal site occurred in 28 (18%) patients. Only smoking (P = 0.003) and neoadjuvant radiotherapy (P = 0.047) were associated with the development of significant flap related complications on univariate analysis. Flap related complications resulted in a significantly longer hospital stay (P < 0.001). CONCLUSION: Careful patient selection is required to balance the risks vs the benefits of VRAM flap reconstruction. Immediate VRAM reconstruction in patients undergoing radical pelvic surgery can achieve early healing and stable perineal closure; it has a low but significant morbidity. Major flap related complications are significantly associated with smoking status and neoadjuvant radiotherapy and result in a prolonged length of hospital stay.

Sentinel lymph node biopsy for melanoma of the head and neck: a multicentre study to examine safety, efficacy, and prognostic value.

Sentinel lymph node biopsy (SLNB) is an accurate staging procedure for malignant melanoma but its use in patients with melanoma of the head and neck has been questioned in the past because of a perceived record of poor safety and accuracy. Technical improvements have sought to redress this. Vital structures and variable lymphatic pathways can make its use in the head and neck challenging. In our study we have examined the data and the experiences of clinicians from University Hospital Southampton and the Royal Surrey County Hospital. We retrospectively analysed the data and case notes of 143 patients who had SLNB to establish its safety, efficacy, and prognostic value. The detection rate of at least one sentinel lymph node was 100%. Nodes positive for metastatic melanoma were found in 20% of patients. Of them, 76% went on to have completion lymphadenectomy. Multivariate Cox regression analysis suggested that positive SLNB was a strong predictor of reduced overall survival for all Breslow-thickness melanomas (HR=3.9, p=0.019) and intermediate melanomas (HR=6.3, p=0.007). It predicted reduced recurrence-free survival for all melanomas (HR=7.4, p<0.001) and was a strong predictor for those of intermediate thickness (HR=8.3, p<0.001). The false negative rate was 9.4% and false omission rate 2.6%. Temporary and permanent morbidity rates were 2.1% and 0%, respectively. SLNB for melanoma in the head and neck is a safe, accurate staging procedure that offers prognostically useful information. The upstaging of disease allows access to trial-based targeted treatments.

Lifting degeneracy in nematic liquid crystal viscosities with a single optical measurement.

The viscosity of complex, anisotropic fluids, such as liquid crystals or their colloidal suspensions, is characterized by a number of coefficients. Methods to measure them are, typically, sensitive only to their particular combinations, hence unable to determine them individually. Using an Ericksen-Leslie model and propagation of light through aligned layers of such materials, we show theoretically and verify experimentally how this degeneracy can be lifted by exploiting both the amplitude and frequency of the voltage applied to the cell as control parameters.

Colonic microbiota can promote rapid local improvement of murine colitis by thioguanine independently of T lymphocytes and host metabolism.

OBJECTIVE: Mercaptopurine (MP) and pro-drug azathioprine are 'first-line' oral therapies for maintaining remission in IBD. It is believed that their pharmacodynamic action is due to a slow cumulative decrease in activated lymphocytes homing to inflamed gut. We examined the role of host metabolism, lymphocytes and microbiome for the amelioration of colitis by the related thioguanine (TG). DESIGN: C57Bl/6 mice with or without specific genes altered to elucidate mechanisms responsible for TG's actions were treated daily with oral or intrarectal TG, MP or water. Disease activity was scored daily. At sacrifice, colonic histology, cytokine message, caecal luminal and mucosal microbiomes were analysed. RESULTS: Oral and intrarectal TG but not MP rapidly ameliorated spontaneous chronic colitis in Winnie mice (point mutation in Muc2 secretory mucin). TG ameliorated dextran sodium sulfate-induced chronic colitis in wild-type (WT) mice and in mice lacking T and B lymphocytes. Remarkably, colitis improved without immunosuppressive effects in the absence of host hypoxanthine (guanine) phosphoribosyltransferase (Hprt)-mediated conversion of TG to active drug, the thioguanine nucleotides (TGN). Colonic bacteria converted TG and less so MP to TGN, consistent with intestinal bacterial conversion of TG to so reduce inflammation in the mice lacking host Hprt. TG rapidly induced autophagic flux in epithelial, macrophage and WT but not Hprt-/- fibroblast cell lines and augmented epithelial intracellular bacterial killing. CONCLUSIONS: Treatment by TG is not necessarily dependent on the adaptive immune system. TG is a more efficacious treatment than MP in Winnie spontaneous colitis. Rapid local bacterial conversion of TG correlated with decreased intestinal inflammation and immune activation.

Voltage transfer function as an optical method to characterize electrical properties of liquid crystal devices.

The voltage transfer function is a rapid and visually effective method to determine the electrical response of liquid crystal (LC) systems using optical measurements. This method relies on crosspolarized intensity measurements as a function of the frequency and amplitude of the voltage applied to the device. Coupled with a mathematical model of the device it can be used to determine the device time constants and electrical properties. We validate the method using photorefractive LC cells and determine the main time constants and the voltage dropped across the layers using a simple nonlinear filter model.

Kinematic dynamo action in square and hexagonal patterns.

We consider kinematic dynamo action in rapidly rotating Boussinesq convection just above onset. The velocity is constrained to have either a square or a hexagonal pattern. For the square pattern, large-scale dynamo action is observed at onset, with most of the magnetic energy being contained in the horizontally averaged component. As the magnetic Reynolds number increases, small-scale dynamo action becomes possible, reducing the overall growth rate of the dynamo. For the hexagonal pattern, the breaking of symmetry between up and down flows results in an effective pumping velocity. For intermediate rotation rates, this additional effect can prevent the growth of any mean-field dynamo, so that only a small-scale dynamo is eventually possible at large enough magnetic Reynolds number. For very large rotation rates, this pumping term becomes negligible, and the dynamo properties of square and hexagonal patterns are qualitatively similar. These results hold for both perfectly conducting and infinite magnetic permeability boundary conditions.

Growth rate degeneracies in kinematic dynamos.

We consider the classical problem of kinematic dynamo action in simple steady flows. Due to the adjointness of the induction operator, we show that the growth rate of the dynamo will be exactly the same for two types of magnetic boundary conditions: the magnetic field can be normal (infinite magnetic permeability, also called pseudovacuum) or tangent (perfect electrical conductor) to the boundaries of the domain. These boundary conditions correspond to well-defined physical limits often used in numerical models and relevant to laboratory experiments. The only constraint is for the velocity field u to be reversible, meaning there exists a transformation changing u into -u. We illustrate this surprising property using S_{2}T_{2} type of flows in spherical geometry inspired by [Dudley and James, Proc. R. Soc. London A 425, 407 (1989)]. Using both types of boundary conditions, it is shown that the growth rates of the dynamos are identical, although the corresponding magnetic eigenmodes are drastically different.

A derived neutrophil to lymphocyte ratio predicts survival in patients with cancer.

BACKGROUND: The neutrophil lymphocyte ratio (NLR) has prognostic value in patients with a variety of cancers. Many chemotherapeutic trial databases hold information on white cell and neutrophil counts only. The aim of the present study was to compare the prognostic value of the NLR with a derived score (dNLR), composed of white cell and neutrophil counts. METHODS: Patients (n=27,031) who were sampled incidentally between 2000 and 2007 for neutrophil, lymphocyte and white cell counts, and also had a diagnosis of cancer (Scottish Cancer Registry), were identified. Of this group, 12,118 patients who had been sampled within 2 years of their cancer diagnosis were studied. RESULTS: On follow-up, there were 7366 deaths, of which 6198 (84%) were cancer deaths. The median time from blood sampling to diagnosis was 2.1 months. The area under the receiver-operating characteristic (ROC) curve for cancer-specific survival was 0.650 for the NLR and 0.640 for the dNLR. The NLR and dNLR were independently associated with survival in all cancers studied (all P<0.001). The optimal thresholds, on the basis of hazard ratios and area under the curve, were 4 : 1 for the NLR and 2 : 1 for the dNLR. CONCLUSION: The results of the present study show that the dNLR has similar prognostic value to the NLR. Therefore, the universally available dNLR is to be commended for use in the risk stratification of patients undergoing chemotherapy.

Systemic inflammation and survival of patients with prostate cancer: evidence from the Glasgow Inflammation Outcome Study.

BACKGROUND: There is some evidence that systemic inflammation may be associated with survival in patients with prostate cancer; however, it is unclear whether this is independent of grade. We therefore investigated the role of inflammation-based prognostic scores, the modified Glasgow Prognostic Score (mGPS) and neutrophil lymphocyte ratio (NLR), and their associations with Gleason grade in patients with prostate cancer. METHODS: Patients from a cohort, the Glasgow Inflammation Outcome Study, who had diagnosis of prostate cancer, were included in this study. The mGPS was constructed by combining C-reactive protein and albumin whereas NLR by calculating the ratio of neutrophils to lymphocytes. We estimated 5-year relative survival and relative excess risk (RER) of death by mGPS and NLR categories after adjusting for age, socioeconomic circumstances and Gleason grade. RESULTS: In all, 897 prostate cancer patients were identified; of those 422 (47%) died during a maximum follow-up of 6.2 years. Systemic inflammation appeared to have significant prognostic value. The mGPS predicted poorer 5-year overall and relative survival independent of age, socioeconomic circumstances, disease grade and NLR. Raised mGPS also had a significant association with excess risk of death (mGPS 2: RER =2.41, 95% confidence interval 1.37-4.23) among aggressive, clinically significant prostate cancer (Gleason grades 8-10). CONCLUSIONS: The mGPS is a strong measure of systemic inflammation, when compared with NLR. Prostate cancer patients with a raised mGPS had significantly higher risk of death for overall as well high-grade disease. Inflammation-based prognostic scores predict outcome in patients with prostate cancer and should be added to their routine clinical assessment.

An inflammation-based prognostic score (mGPS) predicts cancer survival independent of tumour site: a Glasgow Inflammation Outcome Study.

INTRODUCTION: A selective combination of C-reactive protein and albumin (termed the modified Glasgow Prognostic Score, mGPS) has been shown to have prognostic value, independent of tumour stage, in lung, gastrointestinal and renal cancers. It is also of interest that liver function tests such as bilirubin, alkaline phosphatase and γ-glutamyl transferase, as well as serum calcium, have also been reported to predict cancer survival. The aim of the present study was to examine the relationship between an inflammation-based prognostic score (mGPS), biochemical parameters, tumour site and survival in a large cohort of patients with cancer. METHODS: Patients (n=21,669) who had an incidental blood sample taken between 2000 and 2006 for C-reactive protein, albumin and calcium (and liver function tests where available) and a diagnosis of cancer were identified. Of this group 9608 patients who had an ongoing malignant process were studied (sampled within 2 years before diagnosis). Also a subgroup of 5397 sampled at the time of diagnosis (sampled within 2 months prior to diagnosis) were examined. Cancers were grouped by tumour site in accordance with International Classification of Diseases 10 (ICD 10). RESULTS: On follow up, there were 6005 (63%) deaths of which 5122 (53%) were cancer deaths. The median time from blood sampling to diagnosis was 1.4 months. Increasing age, male gender and increasing deprivation was associated with a reduced 5-year overall and cancer-specific survival (all P<0.001). An elevated mGPS, adjusted calcium, bilirubin, alkaline phosphatase, aspartate transaminase, alanine transaminase and γ-glutamyl transferase were associated with a reduced 5-year overall and cancer-specific survival (independent of age, sex and deprivation in all patients sampled), as well as within the time of diagnosis subgroup (all P<0.001). An increasing mGPS was predictive of a reduced cancer-specific survival in all cancers (all P<0.001). CONCLUSION: The results of the present study indicate that the mGPS is a powerful prognostic factor when compared with other biochemical parameters and independent of tumour site in patients with cancer.

The relationship between the presence and site of cancer, an inflammation-based prognostic score and biochemical parameters. Initial results of the Glasgow Inflammation Outcome Study.

BACKGROUND: Cancer incidence is increasing in the United Kingdom, as well as on a global basis. Biochemical parameters, such as C-reactive protein and albumin (combined to form the modified Glasgow Prognostic Score, mGPS), alkaline phosphatase (Alk phos), gamma-glutamyl transferase (GGT) and serum calcium have been reported to be associated with cancer and non-cancer mortality. Therefore, to definitively examine the interrelationships between the above biochemical parameters, the mGPS and the presence of cancer, the Glasgow Inflammation Outcome Study was undertaken. The aim of this initial study was to examine the effect of cancer on markers of systemic inflammation induced by the liver (mGPS) and on levels of routine biochemical parameters. METHODS: Patients (n=223 303) who had a single incidental sample taken for C-reactive protein, albumin, calcium and serum liver function tests where available, between 2000 and 2008 were studied. Those with a pathological diagnosis of cancer (n=22 715) were identified. The mGPS was constructed and liver function tests classified in accordance with the local reference ranges. RESULTS: Patients with cancer had higher C-reactive protein and lower albumin levels (and thus a higher mGPS), higher adjusted calcium, Alk phos and GGT levels, but lower aspartate transaminase (AST) and alanine transaminase (ALT) levels (all P<0.001). The strongest associations (Spearman's correlation > or =0.3) in both the non-cancer and cancer groups were found between albumin, C-reactive protein and Alk phos, AST and ALT, AST and GGT and ALT and GGT (all P<0.001). On multivariate analysis, the associations with the presence of cancer remained with age, deprivation, C-reactive protein, albumin, adjusted calcium, Alk phos and GGT (all P<0.01). Patients following a diagnosis of cancer had lower albumin levels and thus higher mGPS (all P<0.001). Also, post-diagnosis patients were more likely to have lower adjusted calcium, bilirubin, Alk Phos, AST, ALT and GGT levels (all P<0.05). When the cancer diagnoses were ranked from those with the lowest proportion of mGPS 1 or 2 to those with the highest, the percentage of cases with a mGPS of 1 or 2 ranged from 21% in breast cancer to 46% in prostate cancer and to 68% in pulmonary cancer. Compared with breast cancer the mGPS was significantly higher in those diagnosed with dermatological, bladder, endocrinological, gynaecological, prostate, musculoskeletal, gastroesophageal, haematological, renal, colorectal, head and neck, pancreaticobiliary and pulmonary cancers (all P<0.001). CONCLUSION: The results of the present study indicate that the systemic inflammatory response is common in a large patient cohort, increased by the presence of cancer and associated with the perturbation of a number of biochemical parameters previously reported to be associated with mortality. There is a striking parallel between the proportions of cases with a mGPS of 1 or 2 and reported survival rates in these tumours.

Techniques for surgical retrieval of sperm prior to intra-cytoplasmic sperm injection (ICSI) for azoospermia.

BACKGROUND: Azoospermia, the absence of sperm in ejaculated semen, is the most severe form of male-factor infertility and is present in approximately 5% of all investigated infertile couples. The advent of intra-cytoplasmic sperm injection (ICSI) has transformed treatment of this type of severe male-factor infertility. Sperm can be retrieved for ICSI from either the epididymis or the testis, depending on the type of azoospermia. OBJECTIVES: To evaluate the efficacy of the various surgical retrieval techniques for men with obstructive or non-obstructive azoospermia prior to ICSI. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (November 2007), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 4), MEDLINE (1966 to November 2007), EMBASE (1980 to November 2007), Biological Abstracts (1980 to November 2007), and reference lists of identified articles. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing the effectiveness of different sperm-retrieval techniques in men with azoospermia prior to ICSI. Due to the lack of RCTs, non-randomised trials that used the participants as their own control were also considered in the review but their results were not included in the meta-analysis. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. MAIN RESULTS: The search was revised and re-run in November 2007. No new trials were located therefore the results of the updated review remain unchanged from those published in 2006. Two trials involving 98 men were included. The first small RCT had 59 participants and compared two epididymal techniques. The trial gave limited evidence that microsurgical epididymal sperm aspiration (MESA) achieved a significantly lower pregnancy rate (one pregnancy in 29 procedures compared with seven pregnancies in 30 procedures; OR 0.19, 95% CI 0.04 to 0.83) and fertilisation rate (OR 0.16, 95% CI 0.05 to 0.48) than the micropuncture with perivascular nerve stimulation technique. The other RCT comparing two testicular aspiration techniques (TSA) in 39 participants gave no statistically significant evidence for the superiority of the ultrasound-guided technique compared to the aspiration technique without ultrasound. TSA with ultrasound resulted in pregnancy in three out of 16 participants compared with four out of 23 participants (OR 1.10, 95% CI 0.21 to 5.74). AUTHORS' CONCLUSIONS: There is insufficient evidence to recommend any specific sperm retrieval technique for azoospermic men undergoing ICSI. In the absence of evidence to support more invasive or more technically difficult methods, the review authors recommend the least invasive and simplest technique available. Further randomised trials are warranted, preferably multi-centred trials. The classification of azoospermia as obstructive and non-obstructive appears to be relevant to a successful clinical outcome and a distinction according to the cause of azoospermia is important for future clinical trials.

Chinese herbal medicine for primary dysmenorrhoea.

BACKGROUND: Conventional treatment for primary dysmenorrhoea has a failure rate of 20% to 25% and may be contraindicated or not tolerated by some women. Chinese herbal medicine may be a suitable alternative. OBJECTIVES: To determine the efficacy and safety of Chinese herbal medicine for primary dysmenorrhoea when compared with placebo, no treatment, and other treatment. SEARCH STRATEGY: The Cochrane Menstrual Disorders and Subfertility Group Trials Register (to 2006), MEDLINE (1950 to January 2007), EMBASE (1980 to January 2007), CINAHL (1982 to January 2007), AMED (1985 to January 2007), CENTRAL (The Cochrane Library issue 4, 2006), China National Knowledge Infrastructure (CNKI, 1990 to January 2007), Traditional Chinese Medicine Database System (TCMDS, 1990 to December 2006), and the Chinese BioMedicine Database (CBM, 1990 to December 2006) were searched. Citation lists of included trials were also reviewed. SELECTION CRITERIA: Any randomised controlled trials involving Chinese herbal medicine versus placebo, no treatment, conventional therapy, heat compression, another type of Chinese herbal medicine, acupuncture or massage. Exclusion criteria were identifiable pelvic pathology and dysmenorrhoea resulting from the use of an intra-uterine contraceptive device. DATA COLLECTION AND ANALYSIS: Quality assessment, data extraction and data translation were performed independently by two review authors. Attempts were made to contact study authors for additional information and data. Data were combined for meta-analysis using either Peto odds ratios or relative risk (RR) for dichotomous data or weighted mean difference for continuous data. A fixed-effect statistical model was used, where suitable. If data were not suitable for meta-analysis, any available data from the trial were extracted and presented as descriptive data. MAIN RESULTS: Thirty-nine randomised controlled trials involving a total of 3475 women were included in the review. A number of the trials were of small sample size and poor methodological quality. Results for Chinese herbal medicine compared to placebo were unclear as data could not be combined (3 RCTs). Chinese herbal medicine resulted in significant improvements in pain relief (14 RCTs; RR 1.99, 95% CI 1.52 to 2.60), overall symptoms (6 RCTs; RR 2.17, 95% CI 1.73 to 2.73) and use of additional medication (2 RCTs; RR 1.58, 95% CI 1.30 to 1.93) when compared to use of pharmaceutical drugs. Self-designed Chinese herbal formulae resulted in significant improvements in pain relief (18 RCTs; RR 2.06, 95% CI 1.80 to 2.36), overall symptoms (14 RCTs; RR 1.99, 95% CI 1.65 to 2.40) and use of additional medication (5 RCTs; RR 1.58, 95% CI 1.34 to 1.87) after up to three months of follow-up when compared to commonly used Chinese herbal health products. Chinese herbal medicine also resulted in better pain relief than acupuncture (2 RCTs; RR 1.75, 95% CI 1.09 to 2.82) and heat compression (1 RCT; RR 2.08, 95% CI 2.06 to 499.18). AUTHORS' CONCLUSIONS: The review found promising evidence supporting the use of Chinese herbal medicine for primary dysmenorrhoea; however, results are limited by the poor methodological quality of the included trials.

Genetic variation in the dopamine D4 receptor (DRD4) gene and smoking cessation: follow-up of a randomised clinical trial of transdermal nicotine patch.

Smokers of European ancestry (n=720) who participated in a double-blind, randomised, placebo-controlled trial of transdermal nicotine replacement therapy, were genotyped for two functional polymorphisms (variable number of tandem repeats (VNTR) and a C to T transition at position -521 (C-521T)) in the dopamine D4 receptor gene (DRD4) gene. Logistic regression models of abstinence at 12- and 26-week follow-ups were carried out separately for each polymorphism. For the DRD4 VNTR models, the main effect of treatment was significant at both 12-week (P=0.001) and 26-week (P=0.006) follow-ups, indicating an increased likelihood of successful cessation on active nicotine replacement therapy transdermal patch relative to placebo. The main effect of DRD4 VNTR genotype was associated with abstinence at 12-week follow-up (P=0.034), with possession of one or more copies of the long allele associated with reduced likelihood of cessation (17 vs 23%), but this effect was not observed at 26-week follow-up. For the DRD4 C-521T models, no main effect or interaction terms involving genotype were retained in the models at either 12- or 26-week follow-up. These data are consistent with observations from studies of the DRD2 gene that genetic variants related to relatively decreased dopaminergic tone in the mesocorticolimbic system are associated with increased risk for relapse to smoking following a cessation attempt.

Cleavage stage versus blastocyst stage embryo transfer in assisted conception.

BACKGROUND: Recent advances in cell culture media have led to a shift in IVF practice from early cleavage embryo transfer to blastocyst stage transfer. The rationale for blastocyst culture is to improve both uterine and embryonic synchronicity and self selection of viable embryos thus resulting in higher implantation rates. OBJECTIVES: To determine if blastocyst stage embryo transfers (ETs) affect live birth rate and associated outcomes compared with cleavage stage ETs and to investigate what factors may influence this. SEARCH STRATEGY: Cochrane Menstrual Disorders and Subfertility Group Specialised Register of controlled trials, Cochrane Controlled Trials Register (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and Bio extracts. The last search date was January 2007. SELECTION CRITERIA: Trials were included if they were randomised and compared the effectiveness of early cleavage versus blastocyst stage transfers. DATA COLLECTION AND ANALYSIS: Of the 50 trials that were identified, 18 randomised controlled trials (RCTs) met the inclusion criteria and were reviewed. The primary outcome was rate of live birth. Secondary outcomes were rates per couple of clinical pregnancy, multiple pregnancy, high order pregnancy, miscarriage, failure to transfer embryos and cryopreservation. Quality assessment, data extraction and meta-analysis were performed following Cochrane guidelines. MAIN RESULTS: Evidence of a significant difference in live-birth rate per couple between the two treatment groups was detected in favour of blastocyst culture (9 RCTs; OR 1.35, 95% CI 1.05 to 1.74 (Day 2/3: 29.4% versus Day 5/6: 36.0%)). This was particularly for trials with good prognosis patients, equal number of embryos transferred (including single embryo transfer) and those in which the randomisation took place on Day 3. Rates of embryo freezing per couple was significantly higher in Day 2 to 3 transfers (9 RCTs; OR 0.45, 95% CI 0.36 to 0.56). Failure to transfer any embryos per couple was significantly higher in the Day 5 to 6 group (16 RCTs; OR 2.85, 95% CI 1.97 to 4.11 (Day 2/3: 2.8% versus Day 5/6: 8.9%)) but was not significantly different for good prognosis patients (9 RCTs; OR 1.50, 95% CI 0.79 to 2.84). AUTHORS' CONCLUSIONS: This review provides evidence that there is a significant difference in pregnancy and live birth rates in favour of blastocyst transfer with good prognosis patients with high numbers of eight-cell embryos on Day three being the most favoured in subgroup for whom there is no difference in cycle cancellation. There is emerging evidence to suggest that in selected patients, blastocyst culture maybe applicable for single embryo transfer.

Gonadotrophins for idiopathic male factor subfertility.

BACKGROUND: Male factor infertility accounts for 50% of all infertility. The treatment of idiopathic male infertility is empirical. Urinary, purified, and recombinant gonadotrophins have been used to improve sperm parameters in idiopathic male infertility with the goal of increasing pregnancy rates. Research addressing pregnancy rates in partners of men treated with gonadotrophins has had conflicting results and needs to be analysed. OBJECTIVES: To determine the effectiveness of gonadotrophin administration in men with idiopathic subfertility in improving spontaneous pregnancy rate and in assisted reproductive technique cycles. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (31 May 2007), the Cochrane Central Register of Controlled Trials (The Cochrane Library, issue 2, 2007), MEDLINE (1966 to May 2007), EMBASE and Biological Abstracts (1980 to Week 21 2007). Searches were not limited by language. The bibliographies of included, excluded trials and abstracts of major meetings were searched for additional trials. Authors and pharmaceutical companies were contacted for missing and unpublished data. SELECTION CRITERIA: Truly randomised controlled trials where gonadotrophins were administered for the treatment of idiopathic male subfertility with reporting of pregnancy rates were included in the review. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Adverse effects information was collected from the trials. We analysed data regarding pregnancy occurring within three months after gonadotrophin therapy. MAIN RESULTS: Four RCTs with 278 participants were included in the analysis. None of the studies had an adequate sample size and they had variable follow-up periods. None of the studies reported live birth or miscarriage rates. Compared to placebo or no treatment, gonadotrophins showed a significantly higher pregnancy rate per couple randomized within three months of completing therapy ( OR 4.17, 95% CI 1.30 to 7.09). AUTHORS' CONCLUSIONS: The number of trials and participants is insufficient to draw final conclusions. A large multicenter study with adequate power is needed.

Chinese herbal medicine for primary dysmenorrhoea.

BACKGROUND: Conventional treatment for primary dysmenorrhoea (PD) has a failure rate of 20% to 25% and may be contraindicated or not tolerated by some women. Chinese herbal medicine (CHM) may be a suitable alternative. OBJECTIVES: To determine the efficacy and safety of CHM for PD when compared with placebo, no treatment, and other treatment. SEARCH STRATEGY: The Cochrane Menstrual Disorders and Subfertility Group Trials Register (to 2006), MEDLINE (1950 to January 2007), EMBASE (1980 to January 2007), CINAHL (1982 to January 2007), AMED (1985 to January 2007), CENTRAL (The Cochrane Library issue 4, 2006), China National Knowledge Infrastructure (CNKI, 1990 to January 2007), Traditional Chinese Medicine Database System (TCMDS, 1990 to Dec 2006), and the Chinese BioMedicine Database (CBM, 1990 to Dec 2006) were searched. Citation lists of included trials were also reviewed. SELECTION CRITERIA: Any randomised controlled trials (RCTs) involving CHM versus placebo, no treatment, conventional therapy, heat compression, another type of CHM, acupuncture or massage. Exclusion criteria were identifiable pelvic pathology and dysmenorrhoea resulting from the use of an intra-uterine contraceptive device (IUD). DATA COLLECTION AND ANALYSIS: Quality assessment, data extraction and data translation were performed independently by two review authors. Attempts were made to contact study authors for additional information and data. Data were combined for meta-analysis using either Peto odds ratios or relative risk (RR) for dichotomous data or weighted mean difference for continuous data. A fixed-effect statistical model was used, where suitable. If data were not suitable for meta-analysis, any available data from the trial were extracted and presented as descriptive data. MAIN RESULTS: Thirty-nine RCTs involving a total of 3475 women were included in the review. A number of the trials were of small sample size and poor methodological quality. Results for CHM compared to placebo were unclear as data could not be combined (3 RCTs). CHM resulted in significant improvements in pain relief (14 RCTs; RR 1.99, 95% CI 1.52 to 2.60), overall symptoms (6 RCTs; RR 2.17, 95% CI 1.73 to 2.73) and use of additional medication (2 RCTs; RR 1.58, 95% CI 1.30 to 1.93) when compared to use of pharmaceutical drugs. Self-designed CHM resulted in significant improvements in pain relief (18 RCTs; RR 2.06, 95% CI 1.80 to 2.36), overall symptoms (14 RCTs; RR 1.99, 95% CI 1.65 to 2.40) and use of additional medication (5 RCTs; RR 1.58, 95% CI 1.34 to 1.87) after up to three months follow up when compared to commonly used Chinese herbal health products. CHM also resulted in better pain relief than acupuncture (2 RCTs; RR 1.75, 95% CI 1.09 to 2.82) and heat compression (1 RCT; RR 2.08, 95% CI 2.06 to 499.18). AUTHORS' CONCLUSIONS: The review found promising evidence supporting the use of CHM for primary dysmenorrhoea; however, results are limited by the poor methodological quality of the included trials.

Numerical demonstration of fluctuation dynamo at low magnetic Prandtl numbers.

Direct numerical simulations of incompressible nonhelical randomly forced MHD turbulence are used to demonstrate for the first time that the fluctuation dynamo exists in the limit of large magnetic Reynolds number Rm>>1 and small magnetic Prandtl number Pm<<1. The dependence of the critical Rmc for dynamo on the hydrodynamic Reynolds number Re is obtained for 1 less than or similar Re less than or similar 6700. In the limit Pm<<1, Rmc is about 3 times larger than for the previously well-established dynamo at large and moderate Prandtl numbers: Rmc less than or similar 200 for Re greater than or similar 6000 compared to Rmc approximately 60 for Pm>or=1. It is not yet possible to determine numerically whether the growth rate of the magnetic energy is proportional, Rm1/2 in the limit Rm-->infinity, as it should be if the dynamo is driven by the inertial-range motions at the resistive scale.