P–192 Efficacy of postponement of intracytoplasmic sperm injection timing after spindle visualization for Metaphase I oocytes

Study question

Does postponement of intracytoplasmic sperm injection (ICSI) timing after spindle visualization for Metaphase I (MI) oocytes improve developmental outcomes of embryos?

Summary answer

Postponement of ICSI timing after spindle visualization for MI oocytes improves blastocyst utility rates.

What is known already

Immature oocytes are generally considered poor developmental outcomes. Meanwhile, the timing of ICSI adjusted by using spindle visualization can improve clinically utilized embryos and live birth rates, but these outcomes remain inferior to those of mature oocytes. In in vitro maturation culture, nuclear maturation is thought to occur before the completion of cytoplasmic maturation, and in immature oocytes, synchronization of nuclear and cytoplasmic maturation may be insufficient for ICSI immediately after spindle visualization.

Study design, size, duration

Data for this retrospective cohort study were obtained 672 oocytes retrieved under mild stimulation cycles using letrozole, in patients aged younger than 39 years between April 2017 and October 2020.Written informed consent was obtained from all patients. This study was approved by the institutional review board.

Participants/materials, setting, methods

As a control group, 464 MetaphaseIIoocytes that underwent ICSI immediately after visualization of the spindle were used. In group A, 103 MI oocytes underwent ICSI immediately after the first polar body release and spindle visualization, and in group B, 105 oocytes underwent ICSI 2–3 hours after spindle visualization. The primary outcomes were fertilization rates, degeneration, cleavage, embryo blastocyst formation, and utility rates. Outcomes were compared among the three groups.

Main results and the role of chance

The baseline fertilization rates of each group (control, A, B) were 82.3% (382/464), 73.8% (76/103), and 83.8% (88/105), respectively. The rate was significantly lower in group A than in the control group (P < 0.05), and also tended to be lower in group A than in group B, although the difference was not significant. There was no significant difference in abnormal fertilization rates, oocyte degeneration rates, cleavage rates, and blastocyst formation rates among the three groups. [control, A, B: abnormal fertilization rate: 4.3% (20/464), 8.7% (9/103), 4.8% (5/105); oocyte degeneration rates: 3.0% (14/464), 1.9% (2/103), 3.8% (4/105); cleavage rates: 95.6% (307/321), 93.8% (61/65), 98.7% (74/75); blastocyst formation rates: 58.6% (177/302), 51.7% (31/60), 55.4% (41/74), respectively]. The blastocyst utility rates of control group and group B were significantly higher than in group A [41.7% (126/302), 45.9% (34/74), 26.7% (16/60), respectively] (P < 0.05). There were no significantly different outcomes between the control group and group B.

Limitations, reasons for caution

The optimal timing of ICSI for MI oocyte cannot be determined by the presence or absence of spindles. In addition, the postponement duration we set was based on reports which reported on final oocyte maturation, and further investigation is needed to establish the optimal ICSI timing for MI oocytes.

Wider implications of the findings: In MI oocytes, postponement of ICSI timing after spindle visualization is essential for synchronization of the nucleus and cytoplasmic maturation.

Trial registration number

none

P–609 The chances of one live birth rates after first ART cycle in minimal stimulation cycle IVF with letrozole only and natural cycle IVF

Study question

Are one live birth rates (LBRs) similar in minimal stimulation cycle IVF with letrozole only and natural cycle IVF for the first ART cycle?

Summary answer

LBRs after first ART cycle in minimal stimulation cycle IVF with letrozole only are superior to natural cycle IVF.

What is known already

The addition of letrozole to gonadotropins in ovarian stimulation (OS) may reduce the risk of OHSS, but there is no significant difference were reported in ongoing pregnancy rate or number of oocytes retrieved in the letrozole + FSH group compared to the FSH only. No differences were also reported in clinical pregnancy rates or number of mature oocytes in the additional of letrozole in an GnRH antagonist protocol group compared to the GnRH antagonist group. There are no previous study comparing LBRs after first ART cycle in minimal stimulation cycle IVF with letrozole and natural cycle IVF.

Study design, size, duration

Data for this retrospective cohort study were obtained 643 women, 30–39 years of age started their first ART cycle at one private fertility clinic between January 2016- December 2019.

Participants/materials, setting, methods

A total of 643 women were scheduled their first oocyte retrieval cycle. 118 women started with letrozole (LE) and 525 women started natural cycle (NC). The main strategy for OS in our center is minimal stimulation and natural cycle IVF. Patients consulted with gynecologists to determine their treatment plan based on patients’ preference or their menstrual cycle. All pregnancies generated from oocyte retrieval during the first IVF cycle including fresh and frozen-thaw cycles were registered.

Main results and the role of chance

The number of retrieved oocytes and the normal fertilization rates were significantly higher in the LE than NC (4.4 vs 3.4, 77.6% vs 71.1%), p < 0.05 respectively). There was no significant difference in the clinical pregnancy rates (CPRs) per embryo transfer (ET) (fresh cleavage stage ET: 32.9% vs 28.0%, frozen-thaw blastocyst ET: 39.4% vs 44.9% ns). However, the CPRs and LBRs per oocyte retrieval (OR) were significantly higher in the LE group (39.0% vs 28.6, 33.9% vs 21.9%, p < 0.05 respectively). In a subsequent regression analyses, LBRs per OR of LE was significantly higher than NC as well. (adjusted OR = 1.63 (95% CI: 1.02–2.58, p = 0.041).

Limitations, reasons for caution

The strength of the present study was the use of a large cohort of women who underwent minimal stimulation IVF with letrozole only. Although our results are promising, limited by retrospective cohort study. These interpretations prompted the need for a perspective cohort study to evaluate the efficacy of letrozole.

Wider implications of the findings: When comparing minimal stimulation IVF with letrozole only and natural cycle IVF, we found significantly higher LBRs per OR in minimal stimulation IVF with letrozole only, despite similar CPRs per ET.

Trial registration number

none

Computed tomography of odontogenic myxoma

OBJECTIVES

The purpose of this study was to clarify the CT features of odontogenic myxoma.

METHODS

CT appearances were analysed in 17 patients with histologically verified odontogenic myxoma collected from five dental hospitals in Japan.

RESULTS

On the CT images, tumour borders were generally well defined with a smooth margin both for bony and soft tissue structures in all patients. Cortical status was clearly evaluated using CT and the continuity was interrupted in nine patients. Intralesional trabeculations were observed in 13 patients. Of these 13, 6 patients showed the characteristic appearance of angular or straight trabeculations within the tumour. The trabeculations were frequently observed at the peripheral portion of the tumour. In three maxillary tumours, soft tissue margins were observed beyond the cortical margin and/or intralesional trabeculations. In 10 of the 13 lesions evaluated, the majority of the whole tumour area showed relatively lower density compared with surrounding muscles.

CONCLUSION

CT clearly demonstrated characteristic features of odontogenic myxoma. CT analysis may contribute to establishing a consensus regarding the interpretation of conventional radiographic appearances in odontogenic myxoma.

Gelatin-specific cellular immune responses persist for more than 3 years after priming with gelatin containing DTaP vaccine

BACKGROUND

Gelatin-specific cell-mediated immunity develops in subjects inoculated with gelatin containing DTaP vaccine. However, it is not yet known whether such established sensitization to gelatin disappears or persists with time.

OBJECTIVE

The aim of this study was to follow the patients with gelatin sensitization elicited by DTaP vaccination for their lymphocyte responsiveness and IgE, IgG antibody specific to gelatin over several years and to compare the activities with those at the time of enrollment into the study.

METHODS

We studied 28 subjects who developed positive lymphocyte proliferation test (LPT) after receiving gelatin containing DTaP vaccine and eight subjects who had a negative LPT after inoculation of non-gelatin DTaP. Determination of IgE, IgG antibodies and specific lymphoproliferative response directed against gelatin were performed at enrollment and on follow up.

RESULTS

None of the subjects had antibody to gelatin at enrollment and none developed gelatin IgE or IgG during follow-up. There was no significant difference in the SIs of the subjects receiving gelatin DTaP (P = 0.150, 95% CI, -0.198-0.032), whereas lymphocyte activity to gelatin increased between enrollment and follow-up in the subjects with non-gelatin DTaP (P = 0.011, 95% CI, 0.063-0.338).

CONCLUSION

Gelatin-specific lymphocyte activity persists at comparable levels for more than 3 years in subjects who acquire a positive LPT response to gelatin after receiving primary DTaP vaccine containing gelatin. Furthermore, five out of eight subjects initially with negative LPT to gelatin have been shown to acquire specific LPT with time.

Frequency of ciliary body or retinal breaks and retinal detachment in eyes with atopic cataract

AIM

To determine the frequency of ciliary body or retinal breaks and retinal detachment in eyes with atopic cataract.

METHODS

The records of 106 eyes (74 patients) with atopic cataract that underwent cataract extraction were reviewed. The frequency of ciliary body or retinal breaks and retinal detachment was classified by their presence preoperatively and postoperatively, and by cataract type.

RESULTS

Breaks were detected preoperatively in 27 eyes (25.5%) of 17 patients in the ciliary body (20 eyes, 18.9%), near the ora serrata (five eyes, 4.7%), and in undefined locations (two eyes, 1.9%). Among these, 16 eyes (15.1%) had already developed retinal detachment. After surgery, a ciliary body break occurred in one eye (0.9%) and retinal detachment in four eyes (3.8%) of three patients. The breaks that caused postoperative retinal detachment were in the ciliary body. When classified by cataract type, the highest frequency of breaks was associated with mature cataracts (35.0%), and all eyes with breaks developed retinal detachment.

CONCLUSIONS

One fourth of eyes with atopic cataract had breaks in the ciliary body or ora serrata, or retinal detachment preoperatively. The highest frequency of either breaks or retinal detachment was associated with mature cataract. The frequency of breaks or detachment that occurred postoperatively (approximately 5%) was lower than that present preoperatively.

The lymphoproliferative response to enzymatically digested gelatin in subjects with gelatin hypersensitivity

BACKGROUND

This study was designed to evaluate the immunogenic characteristics of enzymatically digested gelatin, 'FreAlagin', employing the lymphoproliferative response in subjects with gelatin hypersensitivity. Our purpose was to assess the response of primed lymphocytes to the newly developed FreAlagin and compare it to the response to conventional gelatin.

METHODS

A gelatin-specific lymphocyte proliferation test (LPT) was performed in 110 children with adverse reactions to gelatin-containing vaccines, who showed positive gelatin-specific cell-mediated immunity and were thus diagnosed as having gelatin hypersensitivity. Gelatin-specific IgE was measured in all subjects. The antigenic activity of FreAlagin to lymphocytes was compared with that of conventional bovine gelatin. Positive and negative control specimens were obtained from the patients with anaphylaxis and from subjects inoculated with gelatin-free vaccine who showed no adverse reactions in order to establish the fluorometric ELISA system to determine IgE antibody to gelatin and LPT.

RESULTS

The lymphocyte activity against FreAlagin was much less than that to Wako gelatin and more than half of the subjects who reacted positively to Wako gelatin had a negative LPT to FreAlagin. Although 47% of the subjects had positive LPTs to FreAlagin, all but two still had lower SIs to FreAlagin compared with Wako gelatin.

CONCLUSION

We conclude that the antigenic activity of FreAlagin as measured by the cell-mediated immune response is significantly less than that of conventional bovine gelatin. However, it is still necessary to perform clinical trials to show a reduced or absent clinical reactivity to FreAlagin in sensitized patients to conventional gelatin.

Gelatin-containing diphtheria-tetanus-pertussis (DTP) vaccine causes sensitization to gelatin in the recipients

Gelatin-specific T cell response was performed to determine whether a series of vaccinations with gelatin-containing DTP is a primary sensitization process in gelatin allergy. Thirty-seven recipients with gelatin-containing DTP who developed adverse reactions after vaccination and eight recipients of DTP without gelatin who also developed adverse reactions were studied. In addition, 10 subjects receiving gelatin-containing vaccine and 10 subjects inoculated with non-gelatin vaccine who did not show any adverse reactions were also investigated. All subjects inoculated with gelatin-containing DTP vaccine showed positive T cell responses against gelatin, however, occurrence of adverse reactions did not correlate with T cell responses. We conclude that DTP vaccine containing gelatin induces sensitization to gelatin in the recipients, but the mechanism of local reactions remains unknown.

Varicella-zoster virus-specific cellular immunity in subjects given acyclovir after household chickenpox exposure

The time course of primary cell-mediated immune responses to varicella-zoster virus (VZV) among persons receiving acyclovir prophylaxis after exposure to chickenpox has not been well defined. Fifteen children who had household exposure to varicella received prophylactic acyclovir (40 mg/kg/day for 7-14 days after exposure) and were studied for development of both antibody and cell-mediated immunity (CMI) to VZV. Twelve developed antibodies and/or CMI; 10 had no symptoms and 2 manifested mild varicella. Two were already immune to varicella and had booster immune responses. One was not infected and subsequently developed full-blown varicella. Although acyclovir given after exposure to VZV is highly effective and does not appear to attenuate the immune response, it remains necessary to confirm whether, in the absence of clinical varicella, persons acquire specific immunity.

Acute fulminant ulcerative colitis with toxic megacolon

An 11-year-old boy with acute fulminant ulcerative colitis (UC) is presented. He had systemic deterioration with frequent diarrhea and lethargy. Acute fulminant UC associated with toxic megacolon was diagnosed by rectal endoscopy and biopsied specimen. He was treated with intensive intravenous administration of prednisolone and total parenteral nutrition. He recovered completely without any surgical intervention.

High dose of intravenous antithrombin III without heparin in the treatment of disseminated intravascular coagulation and organ failure in four children

In several animal experiments, high doses of antithrombin III concentrates have shown beneficial effects on mortality and reversal of coagulation abnormalities which had resulted from disseminated intravascular coagulation. Other experiments have suggested that antithrombin III infusion without heparin is effective in the treatment of organ failure. We clinically treated children suffering disseminated intravascular coagulation only with antithrombin concentrate. Four patients suffering disseminated intravascular coagulation with organ failure were selected. We started antithrombin III concentrate infusion as soon as the diagnosis was established. The dosage of antithrombin III was 120-250 units/kg/day for 2 or 3 days. Heparin was not used. All 4 patients recovered completely and quickly without any complications within 14 days. We suggest that the high-dose antithrombin III infusion without heparin is an effective and safe therapy for disseminated intravascular coagulation with organ failure.

Diagnosis of renovascular hypertension by echo-Doppler velocimetry

A 13 year old boy suffering hypertension was examined for peripheral plasma renin, angiotensin-I, angiotensin-II and aldosterone. All data were within the normal range. The Captopril test and renal scintigraphy (both with and without Captopril) also showed normal patterns. Echo-Doppler velocimetry of the renal artery revealed that left renal arterial peak flow velocity was fast (3.4 m/s). The patient was therefore diagnosed with left renal arterial stenosis. Angiography demonstrated the duplex of the left renal artery and stenosis of the left lower renal artery. Percutaneous transluminal angioplasty was successfully performed.

Bioavailability of calcium from calcium carbonate, DL-calcium lactate, L-calcium lactate and powdered oyster shell calcium in vitamin D-deficient or -replete rats

The bioavailability of calcium from various calcium sources in humans and animals has been the subject of investigation for many years and there is considerable controversy as to the relative bioavailability of different calcium salts. Most of the studies have used a calcium balance technique which has numerous problems in terms of performance and interpretation. Using a method for evaluating the efficacy of calcium from calcium salts used for plasma calcium metabolism and bone mineralization, we examined the bioavailability of calcium from four commercially available calcium salts, namely calcium carbonate, DL-calcium lactate, L-calcium lactate and powdered oyster shell-calcium in vitamin D-deficient or -replete rats. Among the calcium salts, the differences in bioavailability were small and not statistically significant as tested by analysis of variance in both groups of rats. Thus, we conclude that calcium is utilized to the same extent from calcium carbonate, DL-calcium lactate, L-calcium lactate and powered oyster shell-calcium in both vitamin D-deficient and -replete rats.

WBN/Kob rat: a new model of spontaneous diabetes, osteopenia and systemic hemosiderin deposition

A long-term investigation of bone mineral metabolism in a newly developed strain, the WBN/Kob rat, which spontaneously develops diabetes, possibly due in part to hemosiderin deposition, was conducted. WBN/Kob rats used in this study developed diabetes after 9 months of age. Bone mass peaked at 6 months or 8 months of age, and femoral breaking strength was maximal at 8 months of age, declining rapidly after the development of diabetes. In contrast, both the bone mass and the mechanical strength increased up to 14 months of age in controls. The serum osteocalcin (BGP) levels were lower at 4 months of age and serum 1.25(OH)2D levels were significantly lower throughout the study in WBN/Kob rats than in controls. These results suggest that abnormal bone and mineral metabolism is present in WBN/Kob rats before the onset of diabetes, and that bone strength and BMD decrease simultaneously with the development of diabetes. This strain can serve as a useful model, not only of hemosiderosis and diabetes, but also of osteopenia.

The effect of casein phosphopeptides on calcium utilization in young ovariectomized rats

The effect of casein phosphopeptides (CPPs) on Ca utilization in ovariectomized (OVX) rats was studied. A mixture of CPPs corresponding to the amino acid sequences 1-25 and 1-28 in the beta-casein was isolated from the tryptic digest of beta-casein (beta CPP). After being fed a low Ca diet for 30 days, OVX rats were fed experimental diets of which the Ca level was 0.1%, 0.3% or 0.5% with or without 0.15% beta CPP for 28 days. During days 1-3 of the Ca refeeding period, rats fed beta CPP with 0.5% Ca showed a higher Ca absorption than control rats not supplemented with beta CPP. During days 7-9 and 26-28, there were no significant differences in Ca and P balances between the beta CPP group and the control group for each dietary Ca level. Femoral Ca and P contents from rats fed beta CPP tended to be higher than those from control rats. These results suggest that beta CPP supplementation could have an effect on Ca absorption at a certain degree of Ca deficiency.

Stimulation by 1,25-dihydroxyvitamin D3 of in vitro mineralization induced by osteoblast-like MC3T3-E1 cells

Although vitamin D is essential for mineralization of bone, it is as yet unclear whether vitamin D has a direct stimulatory effect on the bone mineralization process. In the present study, the effect of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on in vitro mineralization mediated by osteoblast-like MC3T3-E1 cells was examined. MC3T3-E1 cells continued to grow after they reached confluency, and DNA content and alkaline phosphatase activity increased linearly until about 16 days of culture, whereas 45Ca accumulation into cell and matrix layer remained low. After this period, DNA content plateaued, and 45Ca accumulation increased sharply. Histological examination by von Kossa staining revealed that calcium was accumulated into extracellular matrix. In addition, needle-shaped mineral crystals similar to hydroxyapatite crystals could be demonstrated in between collagen fibrils by electron microscopy. Thus, MC3T3-E1 cells differentiate in vitro into cells with osteoblastic phenotype and exhibit mineralization. When MC3T3-E1 cells were treated with 1,25(OH)2D3 at this stage of culture, there was a dose-dependent stimulation of 45Ca accumulation by 1,25(OH)2D3, and a significant stimulation of 45Ca accumulation was observed with 3 x 10(-10) M 1,25(OH)2D3. Although 1,25(OH)2D3 enhanced alkaline phosphatase activity and collagen synthesis at the early phase of culture, it did not affect any of these parameters at the late phase when 1,25(OH)2D3 stimulated mineralization. Neither 24,25-dihydroxyvitamin D3 nor human PTH(1-34) affected mineralization in the presence or absence of 1,25(OH)2D3. These results demonstrate that 1,25(OH)2D3 stimulates matrix mineralization induced by osteoblastic MC3T3-E1 cells, and are consistent with the possibility that 1,25(OH)2D3 has a direct stimulatory effect on bone mineralization process.(ABSTRACT TRUNCATED AT 250 WORDS)

Heparan sulfate and dermatan sulfate from the liver of a patient with Hurler syndrome: high performance liquid chromatography of their degradation products after incubation with alpha-L-iduronidase-deficient fibroblasts

Using a high performance liquid chromatography method, degradation products of heparan sulfate (HS) and dermatan sulfate (DS) were investigated after incubation of control and alpha-L-iduronidase-deficient fibroblasts with HS or DS. Characteristic elution profiles of the degradation products were obtained from the respective alpha-L-iduronidase-deficient fibroblasts. Moreover, alpha-L-iduronidase in control fibroblasts was resolved into two distinct components, forms A and B, on DEAE-cellulose column chromatography. Form A alpha-L-iduronidase could degrade HS, but not DS. Conversely, form B alpha-L-iduronidase could not degrade HS, but could degrade DS.

Characterization of keratan sulfate isolated from liver affected by Morquio syndrome

Chemical structures of keratan sulfate (KS) isolated from the liver affected by Morquio syndrome type A (classical type) were investigated. In the KS from Morquio syndrome liver, the molar ratios of hexose, total sulfate, N-sulfate and sialic acid to hexosamine were 5.07, 0.90, 0.18 and 0.08, respectively, and about 10% of hexosamine consisted of galactosamine. The KS resulted in a production of oligosaccharides of relatively larger size after digestion with keratanase, as compared with bovine corneal KS. These findings strongly suggest that KS accumulated in the liver affected by Morquio syndrome may be derived from bony KS.