Biomedical subjects
Publications and source records attributed to J Hewitt.
The desire to control the sex of our offspring prior to conception has been present throughout man's history. In recent years the application of a more scientific approach to the problem has resulted in techniques capable of providing interested couples with an 80% chance of having either a boy or a girl according to their wishes. The medical, ethical, economic and sociological implications of these advances will require close attention in future years.
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The present study was carried out to determine whether children at risk for schizophrenia might exhibit abnormalities in test performance indicative of defective interhemispheric integration and abnormal specialization of language function. Twenty-two high-risk and 22 matched normal children were administered two independent tests of speech comprehension, delivered under monaural and binaural listening conditions, and a standard verbal dichotic listening test. On both comprehension tests the high-risk children exhibited significantly poorer binaural, relative to monaural, recall. On the verbal dichotic test the normal group exhibited a significant right ear advantage whereas for the high-risk group there was no significant difference between right and left ear recall. These results were taken to indicate abnormalities of both interhemispheric integration and language specialization in the high-risk group. Analyses indicate that these two abnormalities may be related in a specific fashion. The implications of these results are discussed within a developmental framework.
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Although lichen sclerosus was first described almost a century ago, a grading system was not devised, and the minimal histologic criteria required for diagnosis were not defined. The present study was based on the sequential sectioning of nine vulvectomy specimens removed for invasive carcinoma. Both epidermal and dermal changes were noted, but only the dermal ones were unique to the disease. Early changes included subtle densification of the basement membrane as well as hyalinization of the papillary dermis and superficial capillaries. Based on these findings, a grading system was developed.
The linked DNA marker for Huntington disease has recently been mapped to the short arm of chromosome 4 by somatic cell hybridization studies. Southern blot analysis of DNA from patients with Wolf-Hirschhorn syndrome (WHS) has suggested that the linked marker maps within the terminal 4p16 band. We have now accomplished subregional assignment of G8 (D4S10) to 4p16.1-16.3 using in situ hybridization techniques on two patients with nonoverlapping interstitial deletions of 4p. The mapping of G8 (D4S10) to a region deleted in patients with WHS will allow the application of new strategies for detecting DNA sequences closer to the locus for Huntington disease.
Healthy adult volunteers (no. = 208), men and women aged 30 to 65 years, participated in a 12-week study on dietary fat modification plus oat product ingestion (60 gm/day) to test whether moderate daily intake of oat bran and oatmeal enhanced serum lipid response. During weeks 0 to 6, all participants followed the American Heart Association fat-modified eating style. At 6 weeks, participants were randomly assigned to one of three groups. All participants continued to follow the fat-modified eating pattern; groups 1 and 2 were asked during weeks 7 to 12 to consume two servings of either oat bran or oatmeal per day, for a total of 60 gm/day isocalorically substituted for other carbohydrates. Group 3 ingested no oat products. At baseline, the group mean cholesterol level was 208.4 mg/dl. After 6 weeks of dietary fat intervention, the level was 197.6--a fall of 10.8 mg/dl (5.2%). At 12 weeks, the mean serum cholesterol level fell further, by 5.6, 6.5, and 1.2 mg/dl for groups 1, 2, and 3, respectively. Group mean weight loss was small--1.9 lb during the first 6 weeks and 0.6 to 0.8 for the three groups during weeks 7 to 12. Reported oat product ingestion was 39 and 35 gm per person per day, respectively, for groups 1 and 2 (2.2 and 1.4 servings per person per day, respectively). Dietary fat composition remained similar among the three groups during weeks 7 to 12. Pooled results indicated that the addition of oat products at a moderate and practical level enhanced serum lipid response (p less than .05) to a fat-modified eating pattern among free-living adults.
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The incidence of pregnancy and abortion was analyzed in 1679 patients having embryos replaced after oocyte recovery and in vitro fertilization in order to alleviate their infertility. In these patients, 364 pregnancies were achieved and 108 abortions occurred. Patients were treated either on their natural cycle, having a spontaneous luteinizing hormone (LH) surge to induce ovulation, or after ovarian stimulation using clomiphene citrate alone or in combination with human menopausal gonadotropin (hMG). The data were assessed in relation to the numbers of embryos replaced, the follicular stimulation and ovulation induction regime used, the dose of gonadotropins and the dose of antiestrogens, and the age of the patient. The most successful treatment for the number of live births per laparoscopy was the use of clomiphene citrate in combination with human menopausal gonadotropin followed by human chorionic gonadotropin (hCG) to induce follicular maturation and ovulation. This treatment produced a significantly higher (P less than 0.001) number of patients with multiple embryos (86.5%). There was no significant effect on pregnancy or abortion with a low (less than 400-mg) or high (greater than or equal to 400-mg) dose of clomiphene. The total dose of gonadotropins used did not influence the incidence of pregnancy or abortion. The use of hCG with hMG induced a significant (P less than 0.01) positive effect on the incidence of pregnancy. The incidence of pregnancy showed a progressive decline with increasing age but there was a highly significant (P less than 0.01) increase in the incidence of abortion with increasing age. With increasing numbers of embryos replaced, up to three, the incidence of deliveries increased.(ABSTRACT TRUNCATED AT 250 WORDS)
Antibodies to Chlamydia trachomatis were detected in 54 (47.4%) of 114 infertile women attending Bourn Hall Clinic. Antibodies were solely of the IgG class and mainly of a low titer, suggesting past infection. Antibodies were found in significantly more patients with tubal damage (54.4%) than in women whose infertility was due to other causes (16.6%). Seventy-two women completed in vitro fertilization, with 52 having three embryos replaced. We found that this treatment offered the optimum chance of a pregnancy being established, and 20 (38.5%) of these women became pregnant. Antibodies to C. trachomatis were present in only six (30.0%) of the women becoming pregnant, whereas antibodies were found in 21 (65.6%) of those who failed to become pregnant. Thus past infection with C. trachomatis halved the success rate of in vitro fertilization in these patients. The implications of these findings are relevant to all aspects of infertility from prevention to in vitro fertilization treatment.
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Semen for cryopreservation was collected in a man with a testicular teratoma after unilateral orchidectomy but before chemotherapy which rendered him azoospermic. After two years artificial insemination using this semen in his wife failed repeatedly. The semen quality on thawing was extremely poor in terms of sperm motility. A pre-freeze motility of 90 per cent was reduced to 2 per cent, and the movement was graded as sluggish. Using the techniques of semen and oocyte preparation and in vitro fertilization, a number of cleaving embryos was produced. A pregnancy was established after four of these embryos were replaced in the wife. The pregnancy aborted spontaneously, but a subsequent course of treatment resulted in an on-going twin pregnancy. The potential of in vitro fertilization for overcoming the poor quality of semen after storage by cryopreservation from men with testicular neoplasms is discussed.
Three-quarters of 41 women whose husbands were the cause of infertility in the couple had one or more embryos replaced after in vitro fertilization. One-third became pregnant despite their long history of infertility; the incidence of pregnancy was 45% after one or more replacements of embryos. In a group of 61 couples where both partners were infertile, 26% became pregnant. These data indicate that the lower chance of fertilization with poor semen is balanced by a higher chance of pregnancy in women with a normally functioning reproductive system. Oligospermia, asthenospermia, teratospermia, and autoimmunity are among the many forms of male infertility which can now be successfully treated by in vitro fertilization. Overall, 57% of the oocytes were fertilized, and almost 50% of men with very low numbers of active spermatozoa (less than or equal to 0.5 X 10(6)/ml motile spermatozoa) were successful in establishing pregnancy. Two semen parameters impaired fertilization most: seminal inflammatory cells and low progressive activity. The collection of split ejaculates and the careful preparation of spermatozoa, by sedimentation and layering methods, proved to be beneficial, improving sperm motility and raising the chance of fertilization.
The incidence of pregnancy after in vitro fertilization (IVF) was studied in a group of 38 couples (55 cycles) where both partners were infertile. Cryopreserved donor semen (IVF-D) was used in all cycles. Results were compared with those in a control group of couples where the husband's semen was considered normal and only the wife was infertile. No significant differences were found between the IVF-D and control groups in the incidence of fertilization (80% versus 72%), pregnancy per cycle (33% versus 29%), and abortion (18% versus 20%), despite the considerably lower percentage of motile spermatozoa in the IVF-D group. Forty percent of patients, each treated unsuccessfully with at least 12 artificial inseminations with donor semen, became pregnant after one or two IVF-D cycles. It is concluded that IVF with frozen donor semen is a beneficial treatment for couples where both partners are infertile.
Couples with male infertility (n = 86), idiopathic infertility (n = 68), and cervical mucus hostility (n = 48) of a long duration were treated either by in vitro fertilization (IVF) or artificial insemination with husband's semen (AIH). The incidence of pregnancy per cycle in couples in whom the male partner was infertile was significantly (P less than 0.01) higher after IVF, compared with AIH (21% versus 5%, respectively). The differences were most apparent in couples with asthenospermia (47% versus 0%, respectively); no significant difference was found when the infertility was caused by oligospermia only (11% versus 9%, respectively). More patients with idiopathic infertility became pregnant after one cycle with IVF, compared with AIH (20% versus 8%, respectively); but, because of intragroup disparity in size, this difference was not significant. A highly significant difference (P less than 0.01) was found after one attempt with IVF, compared with AIH, in patients with cervical mucus hostility (38% versus 3%, respectively).
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