Environment and development. Sustainability science.
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Developing Countries↗
Biomedical subjects
P Matson
Publications and source records attributed to P Matson.
Screening standards in assisted reproduction technologies: the screening of semen donors--where do we draw the line?
The most recent British Andrology Society guidelines have certainly stirred up much debate about the exclusion of donors that are seropositive for cytomegalovirus (CMV). Arguments will inevitably go back and forth regarding the statistical risk of donors passing on infection and the point at which that risk becomes unacceptable. As with many of these debates, a number of different opinions will be offered but a consensus will be almost impossible. However, the case of CMV highlights difficulties common to the screening of donors for many infectious and genetic disorders.
Antibodies, Viral↗
Delay in the application of the cover glass is a potential source of error with the Makler Counting Chamber.
OBJECTIVE: To determine the effect of delaying the application of the cover glass of a Makler Counting Chamber (Sefi Medical Instruments, Haifa, Israel) on the apparent concentration of sperm or Dynabeads (Dynal Pty Ltd, Carlton, Victoria, Australia). DESIGN: Systematic alteration of the time taken to apply the cover glass. SETTING: Comprehensive infertility service. PATIENT(S): Fresh semen from a patient or washed sperm from a donor. INTERVENTION(S): For the Makler Counting Chamber, a 5-microL drop of the sperm or bead suspension was placed in the center of the lower platform and the cover glass was applied either immediately (0 seconds) or after a delay of 5, 10, or 30 seconds. MAIN OUTCOME MEASURE(S): The concentration of beads or sperm counted using an Improved Neubauer Hemocytometer or a Makler Counting Chamber. RESULT(S): There was a progressive increase in sperm concentration with a longer delay in applying the cover glass when sperm was suspended in either seminal plasma or culture medium. Repeating the experiments with Dynabeads resuspended in phosphate-buffered saline, serum, or seminal plasma showed the same trend, although the suspension of beads in serum seemed to settle the least over the first 10 seconds. CONCLUSION(S): Delay in the application of the cover glass is a potential source of error with the Makler Counting Chamber and should be avoided.
Female↗
The ratio of X- and Y-bearing sperm in ejaculates of men with three or more children of the same sex.
PURPOSE: The present study evaluated the proportions of X-bearing and Y-bearing sperm within the semen of donors who were the declared fathers of three or more sons or daughters. METHODS: The proportions of sperm were determined using dual-color fluorescence in situ hybridization to identify the X and Y chromosomes. RESULTS: The only difference observed was in semen volume. There was no increase in the proportion of Y-bearing sperm for men with only sons (49.7 +/- 1.3%) or of X-bearing sperm for men with only daughters (44.8 +/- 2.6%). CONCLUSIONS: A preponderance of either sons or daughters in a family cannot be explained simply by an altered ratio of X-bearing and Y-bearing sperm in the father's semen.
Humans↗
The fate of cryopreserved human embryos approaching their legal limit of storage within a West Australian in-vitro fertilization clinic.
Human embryos can only be stored in the first instance for 3 years in Western Australia, according to the West Australian Reproductive Technology Act. Thereafter, an application must be made to the local regulatory body, the Reproductive Technology Council, for an extension. Of the 650 batches of embryos frozen between 8 April 1993 and 31 October 1995, 170 (26.2%) batches were still in storage after 2.5 years. A reminding letter was sent at this time to the couples to whom the embryos belonged, i.e. 6 months before the expiry of the initial storage period, asking for clarification of what was to be done with the embryos. A large proportion of patients (64.7%) chose to either extend the storage period or thaw and transfer the embryos. Curiously, more batches of embryos were discarded (18.8%) than donated to other couples (5.9%). Contact with the patients was lost in a small but significant proportion of cases; more of these had been unsuccessful in their treatment (20.4%) than had achieved a pregnancy (4.3%).
Australia↗
Detection of herpes simplex virus DNA in semen of men with genital HSV-2 infection.
BACKGROUND AND OBJECTIVES: Previous studies, using viral culture, have suggested that herpes simplex virus (HSV) isolation from semen is rare. This study attempts to investigate further the role of semen in sexual transmission of HSV. GOALS OF THIS STUDY: To evaluate semen samples for HSV DNA with a sensitive polymerase chain reaction (PCR) test. STUDY DESIGN: Laboratory examination of 255 stored semen samples collected from 15 healthy men with genital HSV-2 infection during a prospective clinical trial. RESULTS: Herpes simplex virus DNA was detected in 8 (3.1%) semen samples, 6 of which were collected during a herpes recurrence. Herpes simplex virus DNA was not detected in any of the 18 samples collected during acyclovir therapy. CONCLUSION: Herpes simplex DNA can be detected in semen, although it appears closely associated with clinical HSV reactivation. More detailed studies will be needed to assess the role HSV-2 in semen plays in transmission of infection.
Acyclovir↗
Oestradiol and immunoreactive inhibin-like secretory patterns following controlled ovarian hyperstimulation with urinary (Metrodin) or recombinant follicle stimulating hormone (Puregon).
Inhibin (and its alpha-subunit) may be of particular value as a marker for follicular development in in-vitro fertilization (IVF) in comparison with the classic follicle stimulating hormone (FSH)-dependent marker oestradiol in patients following pituitary desensitization and treatment with recombinant FSH (rFSH). This preparation lacks luteinizing hormone (LH), which is essential for thecal cell androgen secretion and thus oestradiol production. Our study has assessed oestradiol and immunoreactive inhibin-like secretion following ovarian stimulation with rFSH or a purified urinary FSH preparation (Metrodin) (uFSH). A randomized, assessor-blind study was initiated using patients receiving a single treatment cycle of IVF (using fresh embryos) following pituitary desensitization with intranasal buserelin (500 microg daily) and the i.m. injection of either rFSH (n = 38) or uFSH (n = 17). Ovarian ultrasound examinations were performed and bloods (10 ml) collected prior to FSH treatment and every 1-2 days until ovulation induction with human chorionic gonadotrophin. LH and FSH concentrations were measured by an immunoradiometric assay, and inhibin-like immunoreactivity by a radioimmunoassay and an enzyme-linked immunosorbent assay, both with alpha-subunit specificity. Oestradiol concentration was measured with a coated tube radioimmunoassay. Following desensitization, basal LH, FSH and oestradiol concentrations were measured, as was that of immunoreactive inhibin. Following treatment with either rFSH or uFSH, LH concentrations remained low while FSH concentrations rose to a plateau of 5.6-6.7 IU/l in both groups. In contrast, the concentration of oestradiol was higher (P < 0.05) with rFSH than with uFSH in the last four days of treatment, a pattern that was repeated for inhibin-like immunoreactivity. The change in oestradiol and inhibin concentrations during treatment was approximately 2-fold higher with rFSH. The total number of follicles obtained with rFSH was similar to that with uFSH. However, the number of follicles with a diameter of >/= 15 mm was higher the rFSH group, and there was a concomitant increase in the number of oocytes recovered. Oestradiol concentration and inhibin-like immunoreactivity (determined by either method) were associated with total follicle number and number of follicles >/= 15 mm in diameter, as well as with each other (P < 0.001). When ovarian hormone output was normalized per follicle produced, oestradiol output was higher for rFSH than for uFSH P = 0.04). Inhibin output was clearly higher using rFSH than uFSH. There were seven pregnancies (one miscarriage) with rFSH and two with uFSH. Despite similar concentrations od FSH in patients, rFSH (Puregon) appears to be more potent in vitro in terms of follicular number, ovarian hormone secretion (both concentration and output/follicle) and oocyte recovery. In both groups, LH concentrations of approximately 1.3 IU/l were sufficient to support oestradiol secretion similar to that normally found in IVF programmes using human menopausal gonadotrophin preparations containing large amounts of LH. Despite known problems of specificity with the assays od inhibin, its measurement was of similar value to oestradiol as a marker of follicular development.
Adult↗
Imported malaria in Montagnard refugees settling in North Carolina: implications for prevention and control.
In the winter of 1992, some 402 Southeast Asian refugees were resettled in North Carolina. They received very limited medical screening before immigration and many arrived in the United States with significant health problems, including several tropical infectious diseases. These refugees had lived for many years in remote areas along the Vietnam-Cambodia border, where there is intense transmission of malaria, including Plasmodium falciparum resistant to most antimalarial drugs available in the United States. Of 322 refugees screened after arrival in North Carolina, 187 (58%) were infected: 33% with P. falciparum, 23.5% with P. vivax, 23.5% with P. malariae, and 2.1% with P. ovale. Most infected persons were asymptomatic and infections with multiple species were common. Because of the documented high infection prevalence and the probable presence of many subpatent infections, all nonpregnant refugees were treated with halofantrine; those with P. vivax or P. ovale infections were given primaquine as well. This group accounted for the largest cluster of malaria cases reported in the United States in the last 50 years. Their rapid relocation, with minimal medical screening prior to arrival, resulted in a significant burden to the refugees and to the health-care system. Coordination between immigration agencies, the public health community, and medical workers in communities where the refugees are settled is critical for U.S.-based management of imported tropical diseases.
Adolescent↗
Insulin-like growth factor binding proteins in serum and follicular fluid from women undergoing ovarian stimulation with and without growth hormone.
The effects of supplementary growth hormone (GH) upon insulin-like growth factor binding proteins (IGFBP) in serum and ovarian follicular fluid were investigated in women undergoing buserelin-human menopausal gonadotrophin (HMG) ovulation induction for in-vitro fertilization. IGFBPs were detected by Western ligand blotting (WLB) or radioimmunoassay (IGFBP-3) and were shown in the present study to increase and decrease in patients with diseases of GH excess or deficiency. In the women undergoing treatment for ovulation induction, radioimmunoassay of IGFBP-3 gave results which were consistent with the well-documented GH dependency of this protein, increasing in the serum when GH was administered at the same time as buserelin-HMG. In contrast there were no consistent patterns in the abundance of the IGFBPs in serum and follicular fluid examined by WLB whether or not the patient was receiving GH, and the IGFBPs varied independently of the result obtained by radioimmunoassay. Other studies have shown that during pregnancy a serum protease can dramatically decrease the detection of the IGFBPs on the WLB. However, there was no evidence for a protease in the serum or follicular fluid from these nonpregnant women undergoing ovulation induction. Tissue availability of IGFs is probably regulated by the BPs, so that data would suggest that in normal women, neither ovarian activity nor GH at pharmacological concentrations is the primary regulator of the IGFBPs, which are likely to be regulated by some other factor(s), e.g. nutrition. These data may account for the lack of consistent clinical improvement in studies investigating the hypothesis that supplementary GH during ovulation induction with gonadotrophins would be beneficial.
Blotting, Western↗
Eosinophilia-myalgia syndrome. Natural history in a population-based cohort.
BACKGROUND: To determine the natural history of eosinophilia-myalgia syndrome, we followed up all patients with eosinophilia-myalgia syndrome reported to the Oregon Health Division, Portland, during the recent epidemic caused by contaminated tryptophan. METHODS: Patients were interviewed by telephone from 1 to 5 months after illness onset and again at least 12 months after onset. Symptoms (type, onset, and duration), overall disability, treatment, and tryptophan lot and dose were assessed for each patient. RESULTS: Information was obtained for 55 (96%) of 57 case-patients: 53 patients completed interviews and two patients had died. For the 53 patients who were interviewed, symptoms with onset more commonly during the first 3 months of illness included severe myalgias, fatigue, generalized weakness, edema, and rash. Symptoms with later onset included paresthesias, muscle cramps, extremity weakness, and alopecia. At 12 months, 41 patients (77%) continued to report fatigue, 36 (68%) weakness, and 34 (64%) myalgias; 26 patients (49%) had difficulty climbing stairs, 23 (43%) had difficulty getting up from a chair, and 15 (28%) had difficulty holding a cup. Higher doses of tryptophan were correlated with more severe disability, both initially (rs = .33) and at follow-up (rs = .42). Although most patients reported improvement in symptoms at 12 months, only 14 (26%) patients reported that they were able to perform all normal daily activities. CONCLUSIONS: Most patients with eosinophilia-myalgia syndrome in this population-based cohort are still symptomatic 1 year after onset, primarily with the complaints reported early in the illness. The association between degree of disability and daily tryptophan dose suggests that ingestion of varying amounts of contaminant may be responsible, in part, for the severity of symptoms experienced by individual patients.
Activities of Daily Living↗
IVF and Goldenhar syndrome.
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Diseases in Twins↗
In-vitro fertilisation for men with obstructive azoospermia.
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Adult↗
A guide to upwardly mobile spermatozoa.
Morphological comparison of sperm in raw ejaculates and swim-ups showed that the swim-up process does not simply increase the proportion of 'normal' sperm. Rather, sperm of specific morphologies have characteristic grades of upward motility.
Humans↗