Charles R. Kingsland

Bio: Charles R. Kingsland is an academic researcher from University of Liverpool. The author has contributed to research in topics: Embryo transfer & Intracytoplasmic sperm injection. The author has an hindex of 23, co-authored 72 publications receiving 2029 citations.

Transvaginal colour flow imaging of the uterine arteries during the ovarian and menstrual cycles

Abstract: Uterine arterial blood flow was studied at defined times during the ovarian or menstrual cycles. Transvaginal colour pulsed ultrasound was used to identify the vessels in 23 healthy women. Blood flow impedance as reflected by the pulsatility index (PI) was determined for both arteries on 132 occasions. There was no significant difference in the PI values between the right and left arteries. The average PI value was used for subsequent analysis (range 0.5-5.6; mean 2.8). Peak mean PI values occurred on day 1 of menses (4.6), the day of the plasma oestradiol peak (3.7) and the day of the LH peak plus 3 (2.9). The lowest mean PI values (indicating the least impedance to blood flow) occurred on the day of the LH peak minus 6 (2.6), and the day of the LH peak plus 9 (1.9). There are complex temporal relationships between uterine blood flow, ovarian morphology, the concentrations of plasma oestradiol and progesterone and the thickness of the endometrium.

Changes in muscle strength in women following the menopause : a longitudinal assessment of the efficacy of hormone replacement therapy

Abstract: The effects of hormone deficiency at the menopause on muscle strength was examined in 10 healthy middle-aged women (1-3 years post-menopause) in a longitudinal trial over 39 weeks. Performance was compared with that of age-matched females (n=11) taking a course of hormone replacement therapy (HRT). Muscle strength of the quadriceps was measured isometrically at 90 degrees of knee flexion and at angular velocities of 1.05, 2.09 and 3.13 rad/s using an isokinetic dynamometer. Hand grip strength was assessed by means of a portable dynamometer. Measurements were taken every 13 weeks for 39 weeks. Significant decreases in isometric strength (-10%) and dynamic leg strength at 1.05 rad/s (-9%) were found in the post-menopausal women over 39 weeks. There was no change in strength in the HRT group. There were also no changes in leg strength at higher angular velocities or in grip strength for either the post-menopausal group or those taking HRT. While HRT preserved muscle strength, there was no evidence of a strengthening effect on skeletal muscle within this short period of treatment. A rapid loss of leg strength occurs post-menopausally in hormone-depleted women. HRT may offer protection against muscle weakness, although the hormone responsible for regulating strength is not evident using this model.

Andrology: Effects of sperm activity on zinc and fructose concentrations in seminal plasma

Abstract: Attempts to correlate zinc and fructose concentrations in seminal plasma with andrological parameters have produced inconsistent results. To assess further this relationship, a prospective study was performed measuring zinc and fructose concentrations in seminal plasma in 1178 patients referred for fertility treatment. Seminal analysis was performed with biochemical measurements of seminal zinc and fructose. The main outcome measures were the correlation between motile sperm concentration and seminal zinc and fructose concentrations. Zinc concentrations were not influenced by the motile sperm concentration (r = 0.039). Fructose concentrations were found to be negatively correlated with motile sperm concentration (r = 0.062). We conclude that seminal plasma zinc is an unreliable marker of spermatogenic activity. While there does appear to be a negative correlation between seminal plasma fructose concentrations and motile sperm concentration this relationship is far from linear. Due to the biochemical complexity of seminal fluid attempts to perform such simple correlations between seminal plasma components and andrological parameters are likely to produce inconsistent results and their role in the assessment of sperm function must therefore be called into question.

Oscillations in intracellular free calcium induced by spermatozoa in human oocytes at fertilization.

Abstract: Calcium has an important role in the events of egg activation and early preimplantation development. We investigated changes in intracellular calcium concentration in human oocytes at fertilization using the calcium-sensitive photoprotein aequorin. Oocytes were donated for research by patients undergoing in-vitro fertilization treatment in the Department of Obstetrics and Gynaecology. Cumulus cells, and in some cases zonae pellucidae, were removed by appropriate enzyme treatment. Single oocytes were micro-injected with aequorin and incubated in a chamber perfused with pre-equilibrated culture medium in a photomultiplier system. Eleven zona-intact and 15 zona-free oocytes were incubated with sperm, and oocytes from each group were incubated without sperm as controls. Dramatic transient increases in intracellular free calcium concentration were recorded in three zona-intact and seven zona-free oocytes, thought to be the first direct measurements of intracellular changes in human oocytes at fertilization. The amplitude (up to 2.5 microM), duration (120 s) and frequency (every 10-35 min) of these transients were similar in zona-intact and zona-free oocytes. They resemble those recorded in mouse oocytes, which may therefore be a suitable model for biochemical events at human fertilization.

Peritoneal fluid concentrations of interleukin-8 in women with endometriosis: relationship to stage of disease.

Abstract: There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.

The evolution of human mating: Trade-offs and strategic pluralism

Abstract: During human evolutionary history, there were "trade-offs" between expending time and energy on child-rearing and mating, so both men and women evolved conditional mating strategies guided by cues signaling the circumstances. Many short-term matings might be successful for some men; others might try to find and keep a single mate, investing their effort in rearing her offspring. Recent evidence suggests that men with features signaling genetic benefits to offspring should be preferred by women as short-term mates, but there are trade-offs between a mate's genetic fitness and his willingness to help in child-rearing. It is these circumstances and the cues that signal them that underlie the variation in short- and long-term mating strategies between and within the sexes.

The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen.

Abstract: The differentiation of the urinogenital system and the appendicular skeleton in vertebrates is under the control of Hox genes. The common control of digit and gonad differentiation raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations. This work was concerned with the ratio between the length of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in right and left hands has a sexually dimorphic pattern; in males mean 2D:4D = 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal length. The dimorphism is present from at least age 2 years and 2D:4D is probably established in utero; (ii) high 2D:4D ratio in right hands was associated with germ cell failure in men (P = 0.04); (iii) sperm number was negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men testosterone concentrations were negatively related to right hand 2D:4D and in women and men LH (right hand), oestrogen (right and left hands) and prolactin (right hand) concentrations were positively correlated with 2D:4D ratio and (v) 2D:4D ratio in right hands remained positively related to luteinizing hormone and oestrogen after controlling for sex, age, height and weight.

Factors associated with

Abstract: Background: The suboptimal compliance to vaccinations continues to be a major public health problem.