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We have investigated the effect of the long-range Coulomb interaction on the one-particle excitation spectrum of n-type germanium, using tunneling spectroscopy on mechanically controllable break junctions. At low temperatures, the tunnel conductance shows a minimum at zero bias voltage due to the Coulomb gap. Above 1 K, the gap is filled by thermal excitations. This behavior is reflected in the variable-range hopping resistivity measured on the same samples: up to a few degrees Kelvin the Efros-Shklovskii lnR infinity T(-1/2) law is obeyed, whereas at higher temperatures deviations from this law occur. The type of crossover differs from that considered previously in the literature.

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OBJECTIVE: To evaluate the cryopreservation of immature human oocytes obtained from unstimulated ovarian tissue. DESIGN: Immature prophase I oocytes were obtained from unstimulated follicles and were either cryopreserved or cultured as controls. Cryopreservation was performed in a programmable freezing machine using one of two protocols. Method I (n = 133) used a one-step addition of cryoprotectant followed by a slow freeze and thaw protocol. With method II (n = 95), the cryoprotectant was added in a stepwise manner with cryopreservation performed in the presence of 0.2 M sucrose followed by rapid freezing and thawing. SETTING: Basic research center at a medical school. PATIENTS: Patients undergoing oophorectomy for nonovarian pathology. MAIN OUTCOME MEASURES: Rates of survival and maturation to metaphase II were compared between control oocytes and oocytes cryopreserved with methods I and II. RESULTS: With method I, a survival rate of 15.6% was obtained with 58.3% of surviving oocytes reaching metaphase II after culture compared with 50.0% of nonfrozen control oocytes. Method II produced a survival rate of 43.3% with 27.3% maturing to metaphase II. Maturation of control oocytes for method II was 46.4%. Although the survival rate with method II was significantly higher than with method I, the rate of in vitro maturation to metaphase II showed no difference. CONCLUSIONS: These results demonstrate that human prophase I oocytes obtained from unstimulated antral follicles are capable of meiotic maturation after cryopreservation.

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Monoclonal antibodies (mAbs) against sperm cells are currently being used in an effort to define spermatozoal antigens involved in the fertilization process. We have produced a number of anti-human sperm mAbs by immunization of female mice with the 100,000 x g supernatant of octylglycoside-solubilized washed human sperm. From a panel of mAbs, 1 antibody, AG7, was selected and characterized due to its fertilization-inhibiting characteristics. MAb AG7 defines a sperm acrosome antigen-1 (SAA-1) located in the acrosomal region of human sperm as evaluated by indirect immunofluorescence. Staining of life sperm cells indicated that the antigen is present on the sperm surface. SAA-1 was also found on sperm of several other mammalian species, implying evolutionary conservation of the antigen. SAA-1 was first observed on testicular sperm and can be followed through epididymal transit, ejaculation, and capacitation. When applied in a mouse in vitro fertilization assay, mAb AG7 inhibits fertilization by greater than 95%, and inhibition is dose dependent, with half-maximal inhibition at 0.8 micrograms/ml. The block to fertilization could not be attributed to sperm agglutination, inhibition of motility, interference with adhesion to the zona pellucida, or inhibition of fusion with the oocyte membrane. MAb AG7 was demonstrated to inhibit calcium influx in spermatozoa in vitro (measured using the fluorescent indicator fura 2), a prerequisite for the acrosome reaction. Initial biochemical characterization of the antigen suggests it is proteinlike in nature, with a molecular weight of approximately 220 kD. The results suggest that SAA-1, identified by mAb AG7, is a sperm antigen crucially involved in the fertilization process, possibly an atypical steroid receptor or ion channel located within the sperm plasma membrane.

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We have established a monolayer culture system for human fallopian tube epithelial cells. The cells were isolated from tubes using collagenase digestion, and were cultured in Ham's F-10 supplemented with 15% fetal calf serum. The epithelial cells derived from culture were characterized using immunocytochemical staining and electron microscopy. These cells were stained with antikeratin and anti-epithelial membrane antigen, but showed no staining after treatment with antivimentin. Electron microscopy showed many microvilli on the cell surface and tight junctions or desmosomes at areas of cell-cell contact. Cell proliferation was enhanced by epidermal growth factor, but not by fibroblast growth factor, insulin, transferrin, estradiol-17 beta, or progesterone. The 2-cell ICR mouse pre-embryos were co-cultured for 4 days with tubal epithelial cells (A) (n = 98), in cell-conditioned medium (B) (n = 83), or in medium alone (C) (n = 72). During the first 24 h in culture, for groups A and B, the rates of cleavage to the 4-cell stage were 90.9% and 81.9%, respectively. Cleavage rates in these two groups were significantly higher (P = 0.0012, P less than 0.00001) than in group C (56.9%). After 72 h in culture, the rates of development to the blastocyst stage were significantly higher for groups A and B compared to group C (89.6% and 73.5% vs. 54.5%, P less than 0.00001, P = 0.0002). These results suggest that factor(s) from tubal epithelial cells may facilitate the development of mouse pre-embryos throughout the pre-implantation stages.

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OBJECTIVE: To compare the usefulness of three micromanipulative methods at two different stages of pre-embryo development and to assess possible effects on postbiopsy survival and development. DESIGN: Four-cell and eight-cell mouse pre-embryos were biopsied using enucleation, aspiration, or extrusion of single blastomeres. After biopsy, pre-embryos were observed for in vitro and in vivo development. SETTING: Laboratories of The Jones Institute for Reproductive Medicine, Department of Obstetrics and Gynecology, Eastern Virginia Medical School. PATIENTS, PARTICIPANTS: Only mice were used. INTERVENTIONS: Pre-embryo biopsy, developmental normalcy and pre-embryo transfer were studied. MAIN OUTCOME MEASURE(S): Few pre-embryos died as a result of biopsy trauma. High postbiopsy survival rates were associated with normal intrauterine and postnatal development. RESULTS: Expanded blastocyst formation rates from four-cell and eight-cell pre-embryos were 94.6%, 96.7% (controls); 80.7%, 89.1% (enucleation); 90.1%, 91.7% (aspiration); 83.1%, 91.5% (extrusion), respectively. Live birth rates at the four-cell stage were slightly lower in the enucleation group than in the blastomere aspiration and extrusion groups or controls (49.2% versus 58.8%, 56.3% and 66.7%, respectively). For the eight-cell stage, there were no differences between the groups. No developmental abnormalities were found in body or organ weights, in neonates or at 3 weeks of age, or in their subsequent ability to reproduce a second generation. CONCLUSIONS: Biopsy of mouse pre-embryos produces only a small loss of viability because of trauma and permits normal prenatal and postnatal development among surviving pre-embryos.

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Growth factors have been shown to play an important role in the regulation of ovarian function. In this study, we examined the effects of transforming growth factor-alpha (TGF-alpha) on the meiotic maturation of immature mouse oocytes in vitro. Cumulus cell-enclosed oocytes were exposed to TGF-alpha with or without the meiotic inhibitor hypoxanthine (HX), and oocyte maturation was assessed by germinal vesicle breakdown (GVBD). Likewise, mechanically denuded oocytes were examined for GVBD following exposure to HX and TGF-alpha. When cumulus cell-enclosed oocytes were exposed to TGF-alpha (1 microgram/ml) in the presence of HX (4 mM), an increase in GVBD was observed first after 5 hours of culture. Maximal stimulation was reached at 24 hours when 70% of the oocytes underwent maturation in the presence of TGF-alpha and HX as compared to 33% with HX only. Concentrations of TGF-alpha as low as 0.1 ng/ml produced a similar stimulatory response after 24 hours of culture. Spontaneous maturation in the presence of TGF-alpha, but without HX, was also enhanced. The stimulation of GVBD by TGF-alpha showed an increase over time both with and without HX. When denuded oocytes were exposed to TGF-alpha in the presence of HX, no effect was observed. Our results suggest that TGF-alpha is a potent stimulator of mouse oocyte maturation in vitro and that its effect is mediated by the surrounding cumulus cells.(ABSTRACT TRUNCATED AT 250 WORDS)

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Cumulus cell-enclosed immature mouse oocytes were matured in medium supplemented with various combinations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol. FSH or LH alone stimulated oocyte maturation, resulting in a significant increase in the rate of development to blastocysts following fertilization in vitro and embryo culture. There was no significant difference between FSH and LH. The effect of FSH was neutralized by FSH antiserum, while that of LH was not, indicating that the stimulation of maturation by LH was not due to FSH contamination in the LH preparation. When LH was added after 2 hr of culture with FSH (sequential combination), blastocyst development was significantly increased compared with FSH alone, reaching the same level as the in vivo matured oocytes. The addition of estradiol, 0.1 ng/ml, to the sequential combination of FSH and LH had no effect, while 0.01 and 1 ng/ml produced a negative effect. The birth rate of normal live offspring following embryo transfer showed no significant difference between embryos derived from oocytes matured in vivo and in vitro (sequential combination with or without 0.1 ng/ml estradiol) or between the two in vitro treatment groups.

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We attempted to improve the developmental potential of mouse oocytes matured in vitro. First, the effect of gonadotropin supplementation of the oocyte maturation medium was tested. The addition of follicle-stimulating hormone (FSH) or luteinizing hormone (LH) alone significantly increased the rate of development of inseminated oocytes to two-cell embryos, resulting in a twofold increase in blastocyst development. There was no significant difference between FSH and LH supplementation. However, the beneficial effect of FSH or LH was abolished when both were added together. Next, we tested the effect of ethylenediaminetetraacetic acid (EDTA) supplementation of the embryo culture medium. The addition of 10 microM EDTA significantly enhanced the development of embryos derived from oocytes matured in vitro, both to two-cell embryos and to blastocysts. These data suggest that the inadequate development of embryos from oocytes matured in vitro results from a defect similar to that inherent in outbred mouse embryos showing the two-cell block in vitro.

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During the 3 years from 1981 to 1983, 319 consecutive patients in 560 cycles were treated in a program of in vitro fertilization at Norfolk. All patients were stimulated by human menopausal gonadotropin supplemented by human chorionic gonadotropin. There were transfers in 429 cycles, resulting in 105 pregnancies. Over the 3-year span, the pregnancy rate by cycle was 19%; by transfer, 25%; and by patient, 33%.

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Three years of progress of the Vital Initiation of Pregnancy (VIP) Program in Norfolk is reported. No conception resulted from 41 oocyte aspirations during spontaneous menstrual cycles in 1980. An average of 3.7 oocytes per cycle, or a 73.5% recovery rate, resulted in 362 human menopausal gonadotropin/human chorionic gonadotropin-induced cycles from January 1981 to March 1983. Forty percent of the oocytes recovered from these cycles were preovulatory, 35% atretic, and 25% immature. Immature oocytes were often matured in vitro, fertilized, and found to produce pregnancies. A total of 62 pregnancies occurred, which represents a 17 or 23% pregnancy rate, based on laparoscopies or embryo transfers, respectively. There were 11 preclinical and 7 clinical miscarriages. Twenty-nine normal babies have been delivered, including a set of twins. The remainder appears to be normally progressing pregnancies. Polyspermia was observed in 8.8% of the fertilizable oocytes.

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One hundred forty-seven cycles in normal ovulatory patients are reported. All were stimulated with human menopausal/human chorionic gonadotropin. Three estrogen responses were identified: normal, high, and low. Patients who achieved pregnancy formed a fourth category, the pregnancy group. The number of preovulatory and immature oocytes, the preovulatory and immature oocytes that fertilized normally or abnormally, the ones that cleaved in culture, and the ones that were transferred were used as parameters to compare quality of the oocytes in each of the estrogen responders. No significant differences were found in any of them. Abnormal zonae pellucidae are described as possibly due to overmaturation of the follicle. No significant difference in the proportion of abnormal zonae in the different categories was found.

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Pregnancy outcome in studies of normal reproduction and in programs of in vitro fertilization (IVF) is usually classified as "chemical beta-human chorionic gonadotropin (beta-hCG) abortion," "trimester abortion," and "term delivery." The distinction between a chemical beta-hCG abortion and a first-trimester abortion is not clearly stated in the literature, although such terms are commonly used. It is proposed that in programs of IVF pregnancy outcome be classified as "menstrual abortion," "preclinical abortion," "clinical abortion," or "viable pregnancy." Pregnancy outcome of 190 consecutive cycles induced by human menopausal gonadotropin/human chorionic gonadotropin in the program of IVF at Norfolk is compared with contemporary studies of pregnancy outcome in normal reproduction. The in vitro data indicate that the Norfolk program has recorded no menstrual abortions, a 33% preclinical and clinical abortion rate, and a viable pregnancy rate that approaches but does not equal the term delivery rate of normal reproduction. However, these results have been achieved by the transfer of multiple concepti, whereas normal reproduction depends on the fertilization of a single oocyte.

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We sampled the reproductive tracts of 27 cynomolgus macaques during the menstrual cycle and correlated the cytologic changes in the oviductal epithelium with changes in the serum levels of estradiol (E2) and progesterone (P) and with the histology of the ovaries and the endometria. We identified an orderly sequence of changes in the oviductal epithelium from the early follicular to the late luteal phase, and we classified this sequence into eight stages, named as follows: preciliogenic, ciliogenic, ciliogenic-ciliated, ciliated-ciliogenic, ciliated-secretory, early regression, late regression and full regression. The preciliogenic and ciliogenic phases were coincident with menses and the early follicular phase. The ciliogenic-ciliated, ciliated-ciliogenic and ciliated-secretory phases during which the oviductal epithelium became progressively more differentiated were coincident, respectively, with the midfollicular, late follicular and periovulatory phases of the cycle. The early, late and full regression stages during which the epithelium became progressively more atrophied, deciliated and nonsecretory were coincident, respectively, with the early, mid and late luteal phases of the cycle. The cyclic changes in the endometrium of cynomolgus macaques were similar to those reported for the rhesus macaque.

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One hundred seventy-five cycles in patients with irreparable tubal disease were stimulated by human menopausal gonadotropin/human chorionic gonadotropin for the purpose of in vitro fertilization. As judged by the height of the peripheral estradiol response, the patients were classified as high, intermediate, or low responders. In addition, the estradiol pattern of the response was found to be separable into six categories. The pregnancy rate was found to be related to the height and to the pattern of peripheral response. The overall pregnancy rate in this consecutive series was 19% but varied according to the height and pattern of response from 40% to 0%.

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In a program for in vitro fertilization, laparoscopies for oocyte aspiration were performed on 24 patients receiving human menopausal gonadotropin and human chorionic gonadotropin. Of the 40 preovulatory oocytes that were recovered from these patients, 33 (83%) were fertilized and 30 (75%) cleaved and were transferred. Ten immature oocytes were collected, and attempts were made to mature these in vitro prior to insemination. All ten oocytes (100%) did fertilize, and seven (70%) cleaved and were transferred. Morphologic variation was noted between cleaving conceptuses, even in those conceptuses responsible for establishing pregnancies. Five pregnancies resulted from 19 embryo transfers (26%).

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Human granulosa-luteal cells were harvested from preovulatory Graafian follicles at the time of oocyte retrieval for in vitro fertilization after induction of follicle maturation by sequential injections of menopausal gonadotropins and hCG. Such highly differentiated granulosa cells produced large quantities of progesterone basally (6.8 pg/cell X 2 days) in monolayer culture. Human LH significantly increased progesterone biosynthesis after 6, 12, 48, 96, or 144 h in culture, with a maximal increase of 8- to 20-fold occurring at 96 h. The stimulatory effect of LH could be observed under serum-free conditions and was maximal in the presence of 4% serum. Human granulosa-luteal cells also exhibited significant stimulatory responses to hCG, prostaglandin E2, or the cAMP effectors 8-bromo cAMP, choleratoxin, or forskolin in serum-free incubations. Concentrations of 17 beta-estradiol that are attained physiologically in ovarian follicles in vivo markedly suppressed basal and LH (or cAMP)-stimulated progesterone production in vitro (maximal suppression, greater than 90%). The nonaromatizable androgen 5 alpha-dihydrotestosterone also inhibited progesterone production, but by no more than 45-50% even at supraphysiological concentrations. Estradiol's blockade of progesterone synthesis was associated with a corresponding increase in pregnenolone accumulation. The present studies indicate that human granulosa-luteal cells isolated from preovulatory follicles induced with exogenous gonadotropins and hCG secrete large quantities of progesterone in vitro. Such cells retain stimulatory responses to human LH, hCG, prostaglandin E2, and classical cAMP effectors in serum-free incubations. Moreover, physiological concentrations of 17 beta-estradiol suppress progesterone production, probably by inhibiting cellular conversion of pregnenolone to progesterone. Thus, the present in vitro system permits an investigation of hormone action in well differentiated, human granulosa-luteal cells isolated from preovulatory Graafian follicles that have a defined endocrine history of prior gonadotropin exposure in vivo.

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Oocytes of varying stages of maturity were aspirated from follicles primed with either human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG) or a combination of follicle-stimulating hormone (FSH), hMG and hCG. Of the aspirated oocytes from 44 cycles, 74 were considered to be immature by virtue of morphologic characteristics of the oocytes and the degree of intercellular expansion of the associated cumular and membrana granulosa cells. After incubation periods of 22 to 35 hours in a Ham's F-10-based culture medium, these immature oocytes were inseminated with sperm donated by the patient's husband. Ultimately, 44 conceptuses were transferred to the respective uteri of 30 patients. Eight pregnancies were established as a result of these 30 transfers, two of which resulted from the transfer of only developed immature oocytes.

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PIP: Details of the transfer of conceptuses into the uterus after fertilization of oocytes in vitro are supplied. Transfer has usually been carried out at the 3- to 6-cell stage about 44 hours after insemination. When the transfer of more than 1 conceptus is done, the 2nd and 3rd conceptuses may be in a much earlier stage of development. The transfer catheter, of American Wire Gauge number 20 Teflon tubing, has an internal diameter of .8636 mm and an outside diameter of 1.4732 mm. A side notch is cut in the tubing so that a stream of liquid forced from the catheter will eject at a 45 degree angle. Each catheter measures about 30 cm in length. Culture medium and conceptus are drawn into the catheter by a 1 ml tuberculin syringe with a number 18 needle. The catheter is inserted through a carrying tube with a slightly curved tip made from number 12 steel needle tubing with a 2.157 mm internal diameter. The catheter is flushed for about 25 cm once or twice prior to loading the conceptus. The conceptus is transferred to a 60 mm tissue culture dish for convenience in loading and to have a flat surface for photography. The conceptus is drawn into the catheter under the microscope in such a way that it lies about 11 cm from the side opening near the catheter tip, with the entire column of medium including 2 air gaps occupying 22 cm of catheter length. Transfer is carried out in the knee-to-chest position so that patients' uteri are in the normal anterior position. Patients receive 250 mg of tetracycline 4 times daily on the day before and the day of transfer. The tip of the metal catheter is inserted barely into the mucus at the external os, and the transfer catheter is passed through the cervix for a predetermined distance. The entire column of medium is quickly ejected, followed by air to clear the catheter. A moment or 2 later the catheter is withdrawn and examined for presence of conceptus. The patient remains prone in the recovery room for a minimum of 4 hours. The procedure was used 94 times from January 1, 1981-June 30, 1982, resulting in 21 pregnancies. Difficulty was encountered only once in passing the catheter into the uterine cavity, and a conceptus was found remaining in the catheter only once after a transfer.^ieng

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Several aspects of the program of in vitro fertilization (IVF), or, as it is called in Norfolk, the program for the Vital Initiation of Pregnancy (VIP), have been or are in the process of publication. However, because there has been no overall account, it seems appropriate to give a brief report of a general nature covering the period from the beginning of the effort in late February 1980 through December 31, 1981. Although minor changes were constantly made in the protocol, there were two major revisions. Therefore, a discussion of the program during three distinct periods, i.e., 1980, 1981-Phase I, and 1981-Phase II, is necessary. During 1980 and 1981 all patients had either no fallopian tubes or irreparable tubes.

PIP: The general procedures utilized in the 2 major phases of the Norfolk in vitro fertilization program in 1981 are described. When the program began, it was believed desirable to exploit the natural menstrual cycle instead of a stimulated controlled cycle, to aspirate the single dominant follicle at the last possible moment prior to expected ovulation, since it was believed impossible to further mature an oocyte in vitro; to utilize a reliable method to predict the hour of ovulation; to utilize a proven aspiration technique; to take extreme measures to maintain a special environment for the oocyte; and to provide means of inseminating the egg with the least possible delay. The results for 1980 were disappointing; from 41 laparoscopies only 19 fertilizable ova were obtained, and no pregnancies resulted from in vitro and in vivo attempts. For phase I beginning in 1981, a protocol was adopted calling for stimulated controlled ovulation using human menopausal gonadotropin (hMG). Exogenous human chorionic gonadotropin (hCG) was used to substitute for the midcycle luteinizing hormone (LH) surge. Laparoscopy for follicular aspiration was scheduled 36-38 hours after hCG administration. The use of a realtime sector ultrasonograph to monitor follicular growth became routine, quality control in the laboratory was tightened, and supplementary maturation in vitro of oocytes prior to insemination was initiated. In Phase I, 48 fertilizable eggs were obtained in 26 of 31 cycles; cleavage was obtained in eggs from 12 cycles, and 2 pregnancies occurred. In 1981-Phase II, several changes in procedures were made. Serum E2 values became available on a daily basis, so that hMG injections could be controlled. There were further improvements in laboratory quality control, such as measures to insure a toxin-free water supply. It became possible to incubate morphologically immature oocytes which subsequently accepted fertilization. In 1981 Phase II, fertilizable eggs were obtained in 22 of 24 laparoscopic cycles, eggs were fertilized from 21 of the 22 cycles, transfers were made in 19 cycles, and there were 5 pregnancies. The importance of transferring more than 1 conceptus became evident from the 31 cycles with transfers: the pregnancy rate was 13% with transfer of a single conceptus, 31% with 2, and 50% with 3.

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