Implications of the Occurrence of Glitches in Pulsar Free Precession Candidates.

The timing properties of radio pulsars provide a unique probe of neutron star interiors. Recent observations have uncovered quasiperiodicities in the timing and pulse properties of some pulsars, a phenomenon that has often been attributed to free precession of the neutron star, with profound implications for the distribution of superfluidity and superconductivity in the star. We advance this program by developing consistency relations between free precession and pulsars glitches, and we show that there are difficulties in reconciling the two phenomena in some precession candidates. This indicates that the precession model used here needs to be modified or some other phenomenon is at work in producing the quasiperiodicities, or even that there is something missing in terms of our understanding of glitches.

Gravitational waves from color-magnetic "mountains" in neutron stars.

Neutron stars may harbor the true ground state of matter in the form of strange quark matter. If present, this type of matter is expected to be a color superconductor, a consequence of quark pairing with respect to the color and flavor degrees of freedom. The stellar magnetic field threading the quark core becomes a color-magnetic admixture and, in the event that superconductivity is of type II, leads to the formation of color-magnetic vortices. In this Letter, we show that the volume-averaged color-magnetic vortex tension force should naturally lead to a significant degree of nonaxisymmetry in systems such as radio pulsars. We show that gravitational radiation from such color-magnetic "mountains" in young pulsars, such as the Crab and Vela, could be observable by the future Einstein Telescope, thus, becoming a probe of paired quark matter in neutron stars. The detectability threshold can be pushed up toward the sensitivity level of Advanced LIGO if we invoke an interior magnetic field about a factor ten stronger than the surface polar field.

Leucocyte subpopulations in the seminal plasma and their effects on fertilisation rates in an IVF cycle.

Controversy exists on the role of leucocytospermia on fertilisation rates and IVF outcomes. The aim of our study was to identify the effect of leucocytes and leucocyte subpopulations on fertilisation rates in an IVF cycle. A prospective comparative study of the leucocyte subpopulations of seminal fluid of partners of women attending an IVF cycle was conducted. The samples underwent immunocytochemical staining. The monoclonal antibodies used in this study include CD3, CD4, CD8 (T Cells), CD14 (monocytes/macrophages), CD16 (granulocytes), CD20 (B Cells), CD45 (Pan Leucocytes), CD56 (natural killer cells) and CD69 (activated T and B Cells). Of 21 patients who were recruited into the study, seven were identified as poor fertilisers (<35%) and 14 were identified as good fertilisers (>60%). Data were analysed with SPSS version 14. The total leucocyte counts (CD45) between the poor and good fertilisers were not statistically significant. The macrophages and the monocytes (CD14) were significantly elevated in the good fertilisers group in comparison with the poor fertilisers (P < 0.05). We also found that T cells (CD2, CD4, CD8) and CD14 (macrophages) correlated significantly (r = 0.47, P value < 0.01) with the fertilisation rate. Our study confirms that the presence of leucocytes does not adversely affect the fertilisation rates and the outcome of an IVF cycle. However, macrophages and the monocytes (CD14) were significantly elevated in the good fertilisers group. The increased phagocytic activity in these individuals might increase their fertilising potential by removing spermatozoa with abnormal morphology.

Cytokine expression in the seminal plasma and its effects on fertilisation rates in an IVF cycle.

Cytokines are released by various immunocompetent cell subsets in the male urogenital tract and are thought to affect sperm cell function and reproductive process. The aim of the study was to evaluate the levels and a possible role of seven seminal plasma cytokines with fertilisation rates in men attending an in vitro fertilisation (IVF) programme. A total of 36 men of couples who were undergoing traditional IVF in a regional reproductive medicine unit were recruited into this prospective study. Cytokines such as interleukin (IL)-6, IL-8, IL-10, IL-11, IL-12, tumour necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) in the seminal plasma were determined using enzyme linked immunosorbent assay. IL-6, IL-8, IL-10, IL-11 and IFN-γ were detected in all samples. IL-12, and TNF-α were detected in most samples. Levels of IL-11 were significantly higher in the good fertiliser group (P ≤ 0.05). Positive correlation between cytokines such as IL-6 and IL-8 (P < 0.03), IL-10 and IL-11 (P < 0.001) and IFN-γ and IL-10 and IL-11 (P < 0.04 and P < 0.0001 respectively) were found. Our study confirms that the six cytokines other than IL-11 do not affect spermatozoon-oocyte interaction and fertilisation rates in IVF. IL-11 could have a role in the fertilising capacity of the spermatozoa. Significant correlation exists among these cytokines which shows that cytokines rarely act in isolation but rather in a network.

The role of cytokine expression in different subgroups of subfertile men.

PROBLEM: The aim of this study was to evaluate the levels of seminal plasma cytokines interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), interleukin 11 (IL-11), interleukin 12 (IL-12), tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) in male subfertility. METHOD OF STUDY: A total of 73 male partners of an infertile couple attending a regional andrology unit were recruited into this prospective study and subdivided into the various groups based on semen analysis. Concentrations of cytokines such as IL-6, IL-8, IL-10, IL-11, IL-12, TNF-alpha and IFN-gamma in the seminal plasma were determined using enzyme linked immunosorbent assay (ELISA). RESULTS: Significant higher concentrations (P < 0.05) of IL-6 in the mild and severe oligospermic group, IL-8 and IL-10 in the asthenospermic group and IL-6, IL-10, TNF-alpha and IFN-gamma in the obstructed azoospermic group were determined. IL-10 concentrations correlated significantly with other cytokines in the obstructed azoospermic group and the asthenospermic group. CONCLUSION: Our study confirms that cytokines rarely act in isolation, but rather in a network of other cytokines and may affect sperm function directly or indirectly. The presence of increased levels of cytokines in the obstructed azoospermic group suggests that the cytokines may not originate from the testis.

Stability of precessing superfluid neutron stars.

We discuss a new superfluid instability occurring in the interior of mature neutron stars with implications for free precession. This instability is similar to the instability which is responsible for the formation of turbulence in superfluid helium. We demonstrate that the instability is unlikely to affect slowly precessing systems with weak superfluid coupling. In contrast, fast precession in systems with strong coupling appears to be generically unstable. This raises serious questions about our understanding of neutron star precession and complicates attempts to constrain neutron star interiors using such observations.

Are neutron stars with crystalline color-superconducting cores relevant for the LIGO experiment?

We estimate the maximal deformation that can be sustained by a rotating neutron star with a crystalline color-superconducting quark core. Our results suggest that current gravitational-wave data from the Laser Interferometer Gravitational-Wave Observatory have already reached the level where a detection would have been possible over a wide range of the poorly constrained QCD parameters. This leads to the nontrivial conclusion that compact objects do not contain maximally strained color crystalline cores drawn from this range of parameter space. We discuss the uncertainties associated with our simple model and how it can be improved in the future.

Does repeated electro-ejaculation improve sperm quality in spinal cord injured men?

STUDY DESIGN: Retrospective analysis. OBJECTIVES: To assess the effect of repeated electro-ejaculation on the sperm quality in spinal cord injured men. SETTING: Regional Spinal Injuries Unit, Southport, UK and Hewitt Center for Reproductive Medicine, Liverpool, UK. METHOD: Retrospective, observational study of men with spinal cord injuries undergoing repeated electro-ejaculation as a part of fertility treatment. RESULT: There was no improvement in the volume, sperm concentration, motility or the total motile count in the successive antegrade and retrograde samples following repeated electro-ejaculations. CONCLUSION: Electro-ejaculation is an invasive procedure and its use should be restricted to obtaining semen sample for carrying out assisted conception procedures only.

A case of rapid deterioration in sperm quality following spinal cord injury.

STUDY DESIGN: Case report. SETTING: Northwest Regional Spinal Injuries Unit, Southport, UK and Reproductive Medicine Unit, Liverpool Women's Hospital, Liverpool, UK. CASE REPORT: A 28-year-old man suffered from paraplegia on sustaining a fall. Fertility preservation was an important aspect of his treatment and electro-ejaculation and cryopreservation of sperm was possible within days of sustaining the fall. The sperm samples obtained subsequently showed a rapid decline in quality. Frozen sperm from the first normal ejaculate obtained soon after the injury was used for assisted reproduction and has resulted in an ongoing pregnancy. CONCLUSION: This case highlights the importance of collection and freezing of seminal fluid within 2 weeks of spinal cord injury (SCI), or earlier to improve fertility outcomes in spinal cord-injured men, as the clinical stability of the patient may allow.

Growing concern over the safety of using mobile phones and male fertility.

There are growing concerns about the possible hazards of electromagnetic waves emitted by mobile phones on human health. One of the biggest concerns is their possible association with increased risk of cancer and their possible effects on cellular DNA. Electromagnetic waves can inflict their results through both thermal and non-thermal effects. There are many animal studies that show that electromagnetic waves have a wide range of damaging effects on the male reproductive system and sperm parameters. However, similar studies are quite limited in humans, and the results of animal studies should be interpreted with caution when considering their application to humans. Large controlled studies are required before confirming such possible effects on male fertility.

Second to fourth digit ratio (2D:4D) and testosterone in men.

AIM: To investigate the relationship between 2D:4D and testosterone in men attending an infertility clinic and men drawn from the general population. METHODS: Data on 2D:4D and testosterone from two samples were collected: (1) 43 men attending an infertility clinic, and (2) 51 men drawn from the general population without regard to fertility. RESULTS: In sample (1) there were negative associations between 2D:4D and testicular function, and men with lower 2D:4D in their right compared to left hand had higher testosterone levels than men with higher 2D:4D in their right compared to left hand. Sample (2) showed no significant associations between 2D:4D or side differences in 2D:4D and testosterone. CONCLUSION: Adult levels of testosterone may be related to aspects of 2D:4D in samples which contain men with compromised testicular function, but not in men from normative samples. Associations between 2D:4D and fertility-associated traits probably arise from early organisational effects of testosterone rather than from activational effects of current testosterone.

Expression of androgen receptors in upper human fetal reproductive tract.

BACKGROUND: Androgens play a key role in human fetal development. All androgens act through a single intracellular androgen receptor (AR), which is encoded by a single copy gene on the X chromosome. ARs are expressed as early as 9 weeks in the epithelium and mesenchyme of the urogenital sinus, paramesonephric (Müllerian) and mesonephric (Wolffian) ducts. METHODS: Using immunohistochemistry, we investigated the distribution of ARs in the gonads and lower genital tracts of 54 human fetuses at 8-11 weeks of gestation. Gender was determined by PCR. RESULTS: The AR was expressed in a similar pattern in both male and female fetuses. There appears to be no difference in expression in the mesonephros or the mesonephric ducts when male and female pelvises were compared. Expression in the female paramesonephric duct was within the epithelium, whereas, in the male pelvises, expression was in the mesenchyme of the paramesonephric duct. When AR expression was compared in the ovary and testes, both gonads seem to express AR at 9 weeks, but this expression was extended into the 10th week of gestation in the male. CONCLUSION: The specific pattern of AR expression implies a key role in gonadal development. However, the pattern of staining was similar in the gonads at 8 and 9 weeks in both sexes, although staining persisted longer in the testis until the 10th week. AR expression, therefore, is not a key determinant of human gonadal differentiation.

Cystic fibrosis mutation screening before assisted reproduction.

Cystic fibrosis (CF) is the most common autosomal recessive disease in Caucasians, with a reported incidence of one in 2500. In 97-98% of men with CF, a congenital bilateral absence of the vas deferens (CBAVD) blocks the transport of spermatozoa from testicular or epididymal structures to the outer genital tract, resulting in azoospermia. Abnormalities in semen parameters have also been identified in males with CF. Around 10% of obstructive azoospermia is congenital and is due to mutations the CF gene. It is therefore suggested that men who have CBAVD should be considered for CF screening prior to intracytoplasmic sperm injection (ICSI) treatment. Men with azoospermia of unknown origin should also be considered for screening. Couples requesting surgical sperm retrieval/ICSI should therefore be advised and counselled to bear an elevated risk for CF in their offspring. Counselling of these couples is vitally important in order to help them understand and cope with the diagnosis.

Current practice in the management of vasectomy reversal and unobstructive azoospermia in Merseyside & North Wales: a questionnaire-based survey.

OBJECTIVE: To investigate the current incidence of vasectomy reversal procedures, the techniques used and which practitioners use them. PATIENTS AND METHODS: Using a questionnaire, 130 general surgeons and urologists practising in Merseyside and North Wales were surveyed. RESULTS: The response rate was 74%, with 24 urological surgeons and 14 general surgeons undertaking vasectomy reversal. Annually, urological surgeons carried out significantly more procedures than did general surgeons, at 8.5 and 5.3 (P = 0.029), respectively. They were also more likely to use double-layer closure and microsurgical techniques, whilst significantly less likely to use stents. Urologists reported significantly greater patency rates, at 76% and 52% (P = 0.017), respectively, with no significant differences in subsequent pregnancy rates (30% vs 25%). Only one practitioner checked tubal patency in the female partner before vasectomy reversal. CONCLUSIONS: The use of vasectomy reversal is a cost-effective treatment for men wanting paternity after vasectomy. The technique used by the clinician and proper audit of the results require close attention; it would also appear to be obvious that all the partners of men seeking a vasectomy reversal should have their fertility status established before reversal, something that is clearly not done at present.

Endometrial integrin expression in women undergoing IVF and ICSI: a comparison of the two groups and fertile controls.

BACKGROUND: Integrins are thought to play a vital role in implantation. Three integrins in particular (alpha(4)beta(1), alpha(v)beta(3) and alpha(1)beta(1)) are all present during the implantation window. Defects in their expression have been linked to tubal disease, unexplained infertility and endometriosis. Hence, a reduced endometrial integrin expression would be expected in women attending for IVF due to these causes of infertility when compared with those with male factor infertility attending for ICSI. METHODS: Women attending for IVF (n = 25) and ICSI (n = 25) treatment were recruited, and timed endometrial biopsies were taken during the 'implantation window' (cycle day 20-24). A group of fertile women (n = 15) attending for sterilization was used as controls. RESULTS: There was no significant difference in integrin expression between patients undergoing IVF or ICSI. Neither did these groups differ from the control group. CONCLUSIONS: The endometrium in patients undergoing ICSI treatment is sometimes thought to be more receptive, as the infertility might be due to a male factor. This study shows that there is no significant difference in integrin expression between patients attending for IVF or ICSI and the control group. These data add to the increasing uncertainty about the clinical value of assessing the endometrium with only one marker, in this case integrins.

Surgical sperm retrieval after previous vasectomy and failed reversal: clinical implications for in vitro fertilization.

OBJECTIVE: To investigate the effect of the interval between previous vasectomy reversal on retrieval rates of epididymal and testicular spermatozoa using percutaneous epididymal sperm aspiration (PESA), or testicular sperm extraction (TESE), and the subsequent reproductive potential of these gametes in intracytoplasmic sperm injection (ICSI) cycles. PATIENTS AND METHODS: Sixty-six consecutive sperm retrievals were considered in patients who were azoospermic after previous vasectomy, of whom 54 had had a previous failed reversal, the remainder deciding against a reversal. PESA and TESE retrieval rates were noted, as were the time since vasectomy and the interval between vasectomy and unsuccessful reversal. The presence of palpable epididymal cysts was noted, with their effect on sperm retrieval rates. Fertilization and pregnancy rates were analysed in subsequent ICSI cycles using freshly retrieved spermatozoa or frozen-thawed cryopreserved spermatozoa. RESULTS: All 66 patients had sperm retrieved successfully; the success rates for PESA were not significantly affected by previous failed reversal when compared with patients who had not had a reversal, at 14 of 54 (26%) vs five of 12 (P=0.3). The interval since vasectomy did not affect PESA retrieval rates but there was a significantly poorer retrieval rate for PESA in the presence of palpable epididymal cysts, at seven of 35 (20%) vs 12 of 23 (52%) (P=0.012). Fertilization rates were significantly lower using cryopreserved spermatozoa retrieved from either the epididymis or testis (50% vs 70%, P=0.007), although subsequent implantation and pregnancy rates were not significantly different. CONCLUSION: Surgical sperm retrieval is successful in all cases of azoospermia secondary to vasectomy, either by PESA or TESE. There are no clinical markers to indicate which patients will have successful PESA after vasectomy, although the presence of epididymal cysts is associated with significantly lower retrieval rates. The reduction in fertilising ability of cryopreserved spermatozoa does not affect clinical pregnancy rates in ICSI cycles.

The effect of gonadotrophic stimulation on integrin expression in the endometrium.

BACKGROUND: Despite many recent advances in IVF treatment implantation rates per embryo transfer rarely exceed 30%. Three integrins (alpha(1)beta(1),alpha(4)beta(1) and alpha(v)beta(3)) have been shown to be expressed in the endometrium in a cyclically dependent manner and are thought therefore to play a vital role in the process of implantation. METHODS: The effect of gonadotrophin stimulation on the expression of these three integrins within the endometrium was investigated by examining biopsies from oocyte donation patients and comparing them with fertile controls. RESULTS: A delay in the maturation of the glandular epithelium was found in the oocyte donation patients. There was also a reduction in the expression of all three integrins in the glandular epithelium and also a reduced expression of the alpha(v)beta(3) integrin in the luminal epithelium. CONCLUSIONS: As these integrins have been shown to be important in implantation their reduced expression after IVF treatment may have an adverse effect on pregnancy rates.

Fructose concentrations in seminal plasma from men with nonobstructive azoospermia.

Fructose is secreted from the seminal vesicles and the accessory sex glands. It is the major carbohydrate source in seminal plasma and essential for normal sperm motility. The objective of this prospective descriptive study was to measure fructose concentrations in seminal plasma from men with obstructive and non-obstructive azoospermia, as determined by serum FSH, and to compare these with fructose concentrations in seminal plasma from men with normal semen parameters. A higher median fructose concentration was observed in seminal plasma from men with azoospermia and a raised serum FSH (3.22 mg/ml) compared to that from men with azoospermia and normal serum FSH (2.30 mg/ml) (p < 0.0001) and to that from normal controls (2.50 mg/ml) (p < 0.0002). This is the first report of increased seminal plasma concentrations of fructose in samples from men with non-obstructive azoospermia. This is either due to a decreased fructose metabolism associated with the azoospermia or, more likely, an increased fructose production from the seminal vesicles.

Comparison of ovarian response in right and left ovaries in IVF patients.

BACKGROUND: Anatomical and cyclical physiological differences exist between right and left ovaries which may affect their function and response to ovulation induction. Although authors have compared right and left ovarian response during IVF for patients with a unilateral diseased or absent ovary, no study has examined the response of normal ovaries to gonadotrophin stimulation within the same patient. We wished to determine if there were any significant differences between right and left ovarian response in patients with healthy ovaries having standard IVF treatment. METHODS: We performed a prospective observational case--controlled study in 200 consecutive IVF patients. The main outcome measures were the number of oocytes retrieved, fertilization rates, grade of embryos produced, pregnancy rates and live birth rates. RESULTS: Comparison of right versus left ovary revealed: number of oocytes 4.9 versus 4.7, percentage fertilization 61.3 versus 62.5%, percentage of grade 1 embryos 81 versus 83%, chemical pregnancy rate 33 versus 47% and live birth rate 27 versus 32% (all not significant). CONCLUSIONS: We conclude that there are no statistical differences between right and left ovarian response in IVF patients with healthy ovaries.