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Biomedical subjects

R M Winston

Publications and source records attributed to R M Winston.

At least 37 records · Page 2Linked to original sources
PubMed1998

One thousand initiated cycles of in vitro fertilization in women > or = 40 years of age.

OBJECTIVE: To evaluate the results of IVF in women > or = 40 years of age using their own oocytes. DESIGN: Retrospective study. SETTING: Wolfson and Royal Masonic in vitro fertilization units, London, United Kingdom. PATIENT(S): A total of 1,087 IVF cycles were started in women > or = 40 years of age. INTERVENTION(S): Medical records of patient outcomes were reviewed. MAIN OUTCOME MEASURE(S): Clinical pregnancy, miscarriage, and delivery rates. RESULT(S): Of the 1,087 cycles started in 471 women > or = 40 years of age, 842 reached oocyte retrieval (77.5%) and 702 had embryos transferred (64.6%). The pregnancy rate (PR) was significantly lower in women > or = 40 years of age than in a control group of women <40 years of age (11.3% versus 28.2%). It decreased sharply in women >42 years of age, and no women >45 years of age had a child. Women > or = 40 years of age were more likely to miscarry (27% versus 12.7%). When only one embryo was available for transfer, the PR was 3.3%. When >2 embryos were available for transfer, the PR was similar whether 2 or 3 embryos were replaced. No triplet pregnancy occurred. Women > or = 40 years of age achieved a cumulative PR of 30% after three cycles with a cumulative "take home baby" rate of 21%. CONCLUSION(S): In vitro fertilization is a reasonable treatment for women <45 years of age using their own gametes. Those with a "good response" in their first attempt may be encouraged to complete three cycles with an acceptable chance of conception.

Adult↗
PubMed1998

Effect of salpingectomy on ovarian response to superovulation in an in vitro fertilization-embryo transfer program.

OBJECTIVE: To investigate the effect of salpingectomy on the response of each ovary in patients undergoing an IVF-ET treatment cycle and to compare the results with those of patients who had not had surgery and were undergoing IVF-ET during the same period. DESIGN: A prospective study. SETTING: Tertiary referral academic IVF unit. PATIENT(S): Twenty-nine ET cycles were evaluated in 29 patients who previously had undergone unilateral salpingectomy because of ectopic pregnancy (study group). Seventy-three patients with unexplained or male factor infertility served as controls. INTERVENTION(S): Ovulation induction and IVF-ET. MAIN OUTCOME MEASURE(S): In the study group, mean ovarian volume, number of follicles, and number of oocytes recovered from each ovary were assessed and compared. The overall results, cycle characteristics, and pregnancy rates of the two groups were compared. RESULT(S): Among the patients who had undergone salpingectomy, significantly fewer follicles developed and consequently fewer oocytes were retrieved from the ovary on the operated side (4.4 versus 8.2 follicles and 3.8 versus 6.0 oocytes). There were no differences in the total numbers of follicles and oocytes recovered from both ovaries, the cycle characteristics, or the pregnancy rates between study and control groups. CONCLUSION(S): Salpingectomy has no detrimental effect on the total ovarian performance during IVF-ET treatment or on the outcome of IVF-ET. However, the ipsilateral ovary could be adversely affected. This could be detrimental in selected patients undergoing IVF-ET, in whom the second ovary already is compromised or missing.

Adult↗
PubMed1998

In vitro fertilization treatment in genital tuberculosis.

PURPOSE: We describe our experience with in vitro fertilization (IVF) treatment in 13 women with histologically proven genital tuberculosis. METHODS: For IVF treatment the above patients had to meet two criteria: normal uterine cavity and functional ovaries. RESULTS: Six intrauterine pregnancies (28.6% success rate) were achieved after 21 IVF treatment cycles in 13 patients with histologically proven diagnoses of genital tuberculosis. This series represents a comparatively encouraging success rate, but these patients were selected carefully before committing them to IVF treatment. CONCLUSIONS: IVF represents a useful treatment and improves the chances of fertility, in what was considered a desperate situation.

Adult↗
PubMed1998

Preimplantation genetic diagnosis of inherited cancer: familial adenomatous polyposis coli.

PURPOSE: Our purpose was to achieve preimplantation genetic diagnosis (PGD) of the dominant cancer predisposition syndrome, familial adenomatous polyposis coli (FAPC), as an alternative to prenatal diagnosis. METHODS: The affected patient was superovulated and oocytes were retrieved and fertilized by intracytoplasmic sperm injection (ICSI). Two cells were biopsied from each embryo and the whole genome was amplified by primer extension preamplification (PEP). Nested PCR was then used to amplify two APC fragments: one including the APC mutation site and the other an informative intragenic polymorphism. Both were detected by simultaneous single-strand conformation polymorphism and heteroduplex analysis. RESULTS: Four normally fertilized embryos were biopsied on day 3 post ICSI, and two cells were successfully removed from each embryo. Following PEP the APC mutation was successfully amplified in 7 of 8 cells, and the polymorphism in 6 of 8 cells. The APC mutation was detected in three embryos. This result was confirmed by identification of the mutation associated polymorphism in two cases. A single embryo was diagnosed as homozygous normal for the mutation and the polymorphism in both cells sampled. This unaffected embryo was transferred to the mother, but no pregnancy resulted. CONCLUSIONS: We report here the first diagnosis of a cancer predisposition syndrome in human preimplantation embryos. Our results indicate that difficulties associated with single-cell PCR, allele-specific amplification failure in particular, need not prevent preimplantation diagnosis of diseases with a dominant mode of inheritance, provided appropriate strategies are applied.

Adenomatous Polyposis Coli↗
PubMed1998

Routine addition of human insulin-like growth factor-I ligand could benefit clinical in-vitro fertilization culture.

Animal studies suggest that the insulin-like growth factors play an important role in preimplantation embryo development. Human preimplantation embryos express mRNA for insulin-like growth factor-I receptor (IGF-IR) but the ligand, insulin-like growth factor-I (IGF-I), is not expressed by the embryo until after implantation. We tested the hypothesis that IGF-I produced by the female reproductive tract may bind to these receptors, augmenting embryo survival, growth and development. Transcripts of mRNA for IGF1 were detected using reverse transcription-polymerase chain reaction in midcycle human Fallopian tube. Immunohistochemistry localized immunoreactive IGF-I to the cytoplasm of all the major structures of the Fallopian tube, with the most intense staining seen in the tubal epithelial lining. Maternally produced IGF-I was present in the fluid found in the human tube and uterus at concentrations of 8.0 and 10.9 nM respectively. Supplementation of culture medium with IGF-I increased the proportion of embryos developing to the blastocyst stage from 35% in controls to 60% in the presence of IGF-I. In addition the total number of cells in day 6 blastocysts was increased by 19% (64.44 versus 54.08% in control, not significant), due entirely to a statistically significant 59% increase (25 versus 15.75%, P = 0.020) in the number of cells in the inner cell mass. The effect of IGF-I was mediated through the IGF-I receptor. Immunocytochemistry using an alphaIR3 antibody confirmed the presence of IGF-I receptor in human blastocysts and the same antibody completely inhibited the stimulation of blastocyst formation by IGF-I. These data suggest that human preimplantation development is enhanced by maternal IGF-I. Mimicking this in-vivo paracrine relationship may improve clinical in-vitro embryo culture and IVF pregnancy rates.

Blastocyst↗
PubMed1998

Predictive value of the results of a first in-vitro fertilization cycle on the outcome of subsequent cycles.

This study examines the relationship between the first cycle of in-vitro fertilization (IVF) and subsequent cycles. The results of all IVF cycles conducted at The Hammersmith Hospital or The Royal Masonic Hospital between 1988 and 1995 were studied including those cycles where egg recovery was abandoned due to poor ovarian response. All patients underwent a standardized treatment protocol. Of those women who achieved a clinical pregnancy during their first IVF attempt, 33% achieved a pregnancy during their second cycle, statistically significantly different from the 24% of patients conceiving during a second cycle who had failed to conceive during their first. 36% of those who achieved a biochemical pregnancy in their first cycle became pregnant in their second. Age was an important factor in the success of IVF treatment, with pregnancy rates of 48% in the 20-25 year age group falling to 8% in those aged > or =41 years. Cumulative pregnancy rates were 26% after one cycle, increasing to 43% after two cycles and reached 80% after seven cycles. A previous pregnancy significantly improved a couple's probability of conception in a later IVF cycle. Overall pregnancy rates per cycle were constant for the first three attempts. Cumulative pregnancy rates continued to rise to 72% after six cycles. Thus the more cycles a couple undergo (up to six) the greater their chance of a pregnancy.

Adult↗
PubMed1998

Culture of human preimplantation embryos to the blastocyst stage: a comparison of 3 media.

Following culture for 2 days in Earle's balanced salt solution (EBSS), human embryos which remained after transfer were cultured in one of 3 media for 4 days, from the 2- to 4-cell stage to the blastocyst stage. Sibling embryos were divided equally between treatments. Throughout the 4 day culture period, embryos were assessed for morphology and development, as well as uptake and production of energy substrates. Cell numbers in the inner cell mass and trophectoderm were determined for embryos which reached the blastocyst stage. No significant effect was observed in the extent or rate of development to the 8-cell, morula or blastocyst stage between treatments. Uptake of pyruvate was related to concentration in the medium and no differences in glucose uptake were observed between media. Endogenous energy metabolism, as measured by lactate production, was significantly higher in Ham's F12 than in EBSS from day 3.5 onwards. Blastocyst cell numbers were also increased; 79.6+/-7.7 in Ham's F12 (n=17) and 57.8+/-5.2 in EBSS (n=19), p<0.05. Of the embryos which reached the blastocyst stage by day 5, 36% (14/25) had degenerated by day 6 in EBSS compared to only 19% (5/27) in Ham's F12 (p=0.06). Slightly higher rates of embryo survival between day 5 and 6 in Ham's F12 may account for the observed increase in blastocyst cell number. The results do not suggest that improved embryo development can be obtained using human tubal fluid or Ham's F12, in preference to EBSS during early cleavage stages, but the use of Ham's F12 may improve embryo survival at later stages of development.

Blastocyst↗
PubMed1997

Expression of mRNA for the insulin-like growth factors and their receptors in human preimplantation embryos.

Insulin, insulin-like growth factor-I (Igf-I), and insulin-like growth factor-II (Igf-II) are known to enhance growth in mouse preimplantation embryos. The addition of insulin, Igf-I, and Igf-II to mouse embryos in culture results in an increase in protein synthesis, cell number, and the proportion of embryos developing to the blastocyst stage. To study the role of the insulin-like growth factors in early human development, the timing of gene expression of insulin, IGF1, IGF2, and their receptors was analysed. Reverse transcription polymerase chain reaction (RT-PCR) was used to examine the presence of transcripts in preimplantation embryos. Following reverse transcription, strategically designed nested primers were used for amplification from cDNA. Transcripts for all three receptors (insulin receptor, IGF1R, IGF2R) were present in human oocytes and preimplantation embryos. However, of the ligands, only IGF2 transcripts were detected. This is consistent with expressed patterns seen in the mouse. As in the human, mouse Igf2 is the only ligand in the family expressed and has been shown to have an autocrine effect on preimplantation development. It has previously been shown that insulin and Igf-I are produced by the mouse maternal reproductive tract and have a paracrine effect on the preimplantation embryo. We speculate that a similar relationship exists in the human and that preimplantation development may be regulated by IGFs from both embryonic (IGF-II) and maternal (insulin and IGF-I) sources.

Animals↗
PubMed1997

Paternal transcripts for glucose-6-phosphate dehydrogenase and adenosine deaminase are first detectable in the human preimplantation embryo at the three- to four-cell stage.

The transition between dependence on maternal transcripts and proteins inherited in the oocyte and embryonic gene expression in the human preimplantation embryo occurs at the four- to eight-cell stage. Recently, studies using reverse transcriptase polymerase chain reaction (RT-PCR) have detected paternal transcripts for the Y-linked genes, ZFY and SRY, and the myotonic dystrophy associated protein kinase gene, DK, as early as the late pronucleate one-cell stage. However, expression at the protein level has not been demonstrated and its function at these early stages is unknown. Using coding sequence polymorphisms to distinguish maternal and paternal transcripts, we have examined the transcription of two ubiquitously expressed genes: X-linked glucose-6-phosphate dehydrogenase (G6PD) and adenosine deaminase (ADA). Both G6PD and ADA are housekeeping genes with TATA-less promoters which, because of their roles in metabolism and ubiquitous expression, may provide a more reliable indication of the timing of activation of the embryonic genome. They also each have biallelic polymorphisms with a high heterozygosity ratio which can be detected by restriction digestion. Couples undergoing in vitro fertilization (IVF) were screened for these polymorphisms. Individual spare oocytes and embryos at different stages of preimplantation development were analyzed by RT-PCR and appropriate restriction digestion in those cases in which the male partner carried a different allele to the female partner. In addition, since only female embryos inherit the paternal allele of X-linked G6PD, cDNA was also analyzed for ZFX/ZFY transcripts to identify the sex of each embryo. One hundred and twenty three individual oocytes and embryos were analyzed by RT-PCR and restriction digestion to detect the paternal transcripts from the polymorphic alleles. Maternal transcripts for G6PD, ADA, and ZFX were detected in all oocytes and embryos and at all stages. Following restriction digestion, paternal G6PD and ZFY transcripts were first detected at the four-cell stage and paternal ADA transcripts in an embryo at the three-cell stage coinciding with the onset of dependency on transcription from the embryonic genome. This approach should be widely applicable to other genes since similar polymorphisms exist in the coding regions of many genes.

Adenosine Deaminase↗
PubMed1997

Multicolour FISH detects frequent chromosomal mosaicism and chaotic division in normal preimplantation embryos from fertile patients.

We have used multicolour fluorescent in situ hybridisation (FISH) with DNA probes for chromosomes X, Y and l to analyse spare untransferred cleavage-stage embryos after preimplantation diagnosis to avoid X-linked disease. In total, 93 morphologically normal embryos were available from seven patients (six of proven fertility) who had undergone fourteen in vitro fertilisation (IVF) cycles. The chromosome patterns observed were classified into four groups; normal, abnormal (non-mosaic), mosaic and chaotic (uncontrolled division). Approximately half of the embryos were normal for the chromosomes tested. Two embryos only were aneuploid (non-mosaic) throughout but, after excluding those showing chaotic division, 30% were considered to be chromosomal mosaics. Of these, a minority had arisen because of mitotic non-disjunction or chromosome loss or gain, whereas the majority were ploidy mosaics, with haploidy being the most common. The occurrence of chaotically dividing embryos was strongly patient-related, i.e. some patients had 'chaotic' embryos in repeated cycles, whereas other patients were completely free of this type of anomaly. 'Chaotic' embryos are unlikely to progress beyond implantation. These findings have important implications both for routine IVF and preimplantation genetic diagnosis.

Adult↗
PubMed1997

Mechanical isolation and in vitro growth of preantral and small antral human follicles.

OBJECTIVE: To develop a procedure for isolating small human follicles and to determine their growth requirements. DESIGN: Preantral and early antral follicles were isolated manually, allocated randomly to experimental groups, and cultured for a few weeks. SETTING: Patients giving informed consent in hospitals. PATIENT(S): Women undergoing laparotomy or oophorectomy. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Follicular size, E2, histology. RESULT(S): Human FSH (at a dose of 1.5 U/mL) induced antral growth of follicles, and the addition of human LH (2.5 ng/mL) to human FSH stimulated growth and antral development. Histologic studies showed that most of the early antral follicles did not contain an oocyte and already had begun to undergo atresia before culturing. Levels of E2 increased in the incubation medium as the follicles increased in size, but those levels were significantly greater when the follicles contained oocytes. CONCLUSION(S): It is possible to grow small human follicles after they have been isolated manually. To develop successfully, they require a low concentration of human LH in addition to human FSH. The rate of atresia between the preantral and early antral stages in vivo is very high; therefore, it is worthwhile to develop techniques for isolating and culturing the follicles before the antral stages.

Adult↗
PubMed1997

Increased follicular fluid total and free cortisol levels during the luteinizing hormone surge.

OBJECTIVE: To determine the changes in follicular fluid (FF) total and free cortisol during the LH surge in naturally ovulating women. PATIENT(S): Twenty-six women having diagnostic laparoscopy during the follicular phase of normal menstrual cycles were selected. INTERVENTION(S): Blood samples were collected 1 day before, the day of, and 1 day after surgery and the results of serum E2 and LH were used to divide the cycles retrospectively into pre- and post-LH surge groups. Follicular fluid was collected during laparoscopy. MAIN OUTCOME MEASURE(S): Serum P, total and free cortisol, and FF volume, E2, P, total cortisol, and free cortisol were measured on the day of surgery. RESULT(S): Median serum and FF P levels were significantly higher in the post-LH surge group compared with the pre-LH surge group (0.54 versus 1.54 ng/mL [1.7 versus 4.85 nmol/L] and 5.03 versus 28.0 micrograms/mL [15.8 versus 88.0 mumol/L], respectively). Follicular fluid volume also increased significantly after the surge (2.5 versus 4.5 mL). Median serum total and free and percent free cortisol were higher after the surge, although not significantly. In contrast, FF total, free, and percent free levels increased dramatically between pre- and post-LH surge samples (4.41 versus 43.6 ng/mL [16.0 versus 158 nmol/L], 0.138 versus 6.68 ng/mL [0.5 versus 24.2 nmol/L], and 3.3% versus 15.0%, respectively; P < 0.05). CONCLUSION(S): An increase in total and free cortisol occurs in the follicle during the LH surge. Cortisol and its regulation by 11 beta-hydroxysteroid dehydrogenase therefore may exert a physiologic role in oocyte maturation or ovulation.

Estradiol↗
PubMed1997

XIST expression from the maternal X chromosome in human male preimplantation embryos at the blastocyst stage.

In the somatic cells of female mammals, either the maternally or paternally derived X chromosome (X(M) or X(P)) is randomly inactivated to achieve dosage compensation for X-linked genes. In early mouse development, however, selective inactivation of X(P) occurs first in extraembryonic lineages at the blastocyst stage around the time of implantation before later random inactivation in the embryonic ectoderm from which the fetus is derived. Xist, a gene mapping to the X-inactivation centre (Xic), is exclusively expressed from the inactive X-chromosome and is thought to be involved in the initiation of X-inactivation. Consistent with this, Xist is first expressed at the 4-to 8-cell stages, prior to functional inactivation at the blastocyst stage, exclusively from X(P) in female embryos. This also suggests that genomic imprinting may influence the earliest expression of Xist resulting in selective inactivation of X(P) and a candidate methylation site in the promoter region has recently been described. Here we report the expression of the human homologue, XIST, in human preimplantation embryos from the 5- to 10-cell stage onwards consistent with its role in the initiation of inactivation. In contrast to the mouse, however, transcripts were detected in both male and female embryos demonstrating XIST expression from the X(M) in male embryos (X(M)Y).

Animals↗
PubMed1997

Measurement of ovarian volume by transvaginal sonography before ovulation induction with human menopausal gonadotrophin for in-vitro fertilization can predict poor response.

The study tests the hypothesis that small ovaries measured on transvaginal sonography (TVS) are associated with a poor response to ovulation induction by human menopausal gonadotrophin (HMG) for in-vitro fertilization (IVF). A total of 140 infertile patients with morphologically normal ovaries undergoing IVF was studied. The mean ovarian volume of each patient was measured on TVS before starting HMG. Subsequent routine IVF management was conducted without knowledge of the results of TVS. The mean ovarian volume was 6.3 cm3 (range 0.5-18.9, SD= 3.1). Patients (n = 17; group A) with small ovaries of < 3 cm3 (i.e. overall mean volume - 1 SD) were compared to patients (n = 123; group B) with ovaries > or = 3 cm3. Both groups were of similar age (mean 35.8 versus 34.4 years). Early basal FSH concentrations were increased in group A (9.5 versus 7.0 mIU/ml, P = 0.025). The cycle was abandoned before planned oocyte recovery in nine patients (52.8%) from group A and in 11 patients (8.9%) from group B because of poor response to ovulation induction (P < 0.001). Increased age and ovarian volume were associated independently with cancellation of the cycles. The remaining eight patients from group A who had oocytes retrieved required higher doses of HMG (87.5 versus 53.8 ampoules, P < 0.01), yielded fewer follicles (10.3 versus 14.5, P < 0.05) and fewer oocytes were recovered from them (6.8 versus 11.0, P < 0.05) compared with group B. There was no difference in the fertilization or pregnancy rates or the number of embryos available for transfer in either group. Our results indicate a strong association between ovarian volume and ovarian reserve. Small ovaries are associated with poor response to HMG and a very high cancellation rate during IVF. Assessment of ovarian size should be an integral part of infertility evaluation.

Adult↗
PubMed1997

Women with one ovary have decreased response to GnRHa/HMG ovulation protocol in IVF but the same pregnancy rate as women with two ovaries.

The study compares the response after gonadotrophin-releasing hormone agonist (GnRHa) and human menopausal gonadotrophin (HMG) stimulation for in-vitro fertilization (IVF) in patients with either one or two ovaries. The study group (group A) included 73 cycles in women who had unilateral oophorectomy before their IVF treatment and the control group (group B) included 988 cycles in women with two ovaries. Tubal disease was the sole cause for infertility in all cases. The two groups were similar in age and parity. The patients with one ovary required more ampoules of HMG (62.9 versus 48.9, P < 0.001), a longer induction period (13.5 versus 12.7, P < 0.01) and had significantly lower oestradiol concentrations on the day of human chorionic gonadotrophin (HCG) administration (5840 versus 6473 pmol/l, P = 0.035). They yielded fewer follicles (11.2 versus 13.1, P = 0.005), fewer oocytes (7.3 versus 9.1, P = 0.006) and produced fewer embryos (4.4 versus 5.1, P < 0.05). There was no difference in fertilization rate (60 compared with 58%), or pregnancy rate (25.8 compared with 27.1% per oocyte retrieval). Women with only one ovary responded less well to GnRH agonist/HMG stimulation than women who had both ovaries but pregnancy outcome was the same in both groups.

Adult↗
PubMed1997

Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve.

The ageing ovary appears to be characterized by depletion of primordial follicles. The relationship between infertility and the number of follicles in the ovarian cortex is not known. Moreover, there are no accurate markers or clinical methods to predict the decline in ovarian reserve. This study investigates the correlation between early follicular follicle stimulating hormone, ovarian size and follicular density in 60 infertile women aged 19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each patient while performing diagnostic laparoscopy (n = 28) or laparotomy for tubal surgery or myomectomy (n = 32). The median number of follicles was similar in tubal and unexplained infertility patients (9.5 versus 5.5). Increasing age showed a significant negative correlation with follicular density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016, respectively). In women > or = 35 years of age the ovarian volume showed a strong correlation with follicular density (r = 0.71, P < 0.0001). Our results indicate that infertile women in their late thirties and over have a decreased ovarian reserve which could possibly be predicted by ovarian volume measurement. Ovarian biopsy may have a place as part of infertility evaluation in older women.

Adult↗
PubMed1997

Extracellular matrix improves survival of both stored and fresh human primordial and primary ovarian follicles in long-term culture.

Ovarian cortical tissue was obtained during gynaecological operations by biopsy or after oophorectomy from 20 women aged 25-42 years. It was placed in organ culture, either fresh or following thawing after cryopreservation, for 1-4 months. The tissue was cut in slices 0.1-0.3 mm in diameter and transferred to 12 mm inserts in 24-well culture plates. These slices were cultured for 4-21 days in either alpha minimum essential medium (alpha-MEM) or Earle's balanced salt solution with added pyruvate. Both media were supplemented with 10% human serum, insulin, gonadotrophins and antibiotics. Half of the inserts were precoated with extracellular matrix (Matrigel). Histological samples revealed that there were viable, non-atretic, primordial, primary and secondary follicles in all the cultures. Mitoses were seen in the granulosa cells of the secondary follicles. Although the proportion of atretic follicles increased during culture, non-atretic follicles were still present after 21 days. After 4-11 days the proportion of viable follicles was significantly higher when cultured in Earle's solution supplemented with pyruvate, than when cultured in MEM (77 versus 38%, P < 0.001). In cultures with extracellular matrix the proportion of viable follicles was significantly higher after 10-15 days than it was without matrix (85 versus 19%, P < 0.001). Culture after thawing frozen ovarian tissue did not affect the density or the proportion of the viable follicles. Two-thirds of follicles in cryopreserved tissue were viable after 10-15 days in culture. The results indicate that it is possible to culture human primary and primordial follicles in vitro, and follicles in cryopreserved tissue are viable.

Adult↗