Effect of adding individualized occupational therapy to standard care on rehospitalization of patients with schizophrenia: A 2-year prospective cohort study.

AIM: We examined the effect of individualized occupational therapy (IOT) compared to the usual group occupational therapy (GOT) on the rehospitalization of patients with schizophrenia. METHODS: A prospective cohort study included patients with schizophrenia who were discharged within 1 year from a psychiatric hospital. Time to rehospitalization by treatment group (GOT + IOT or GOT-alone) was evaluated with Kaplan-Meier survival analysis. The impact of demographics and clinical factors associated with rehospitalization was investigated using Cox proportional hazards models. RESULTS: Of the 111 patients who met the criteria, 54 were in the GOT + IOT group and 57 in the GOT-alone group. Over the 2 years from discharge, the overall rehospitalization rate was 51.376% (56 patients); the GOT + IOT group demonstrated a significantly lower rehospitalization rate with 16 patients rehospitalized compared to 40 patients from the GOT-alone group. Time to rehospitalization was significantly longer for the GOT + IOT group compared to those in the GOT-alone group (P < 0.001). The multivariate Cox proportional hazards models showed that type of occupational therapy (hazard ratio [HR] = 0.543), medication adherence (HR = 0.343), access to resident support persons (HR = 0.450), and executive function at discharge (HR = 0.740) were all significantly associated with rehospitalization. CONCLUSION: Our results provide support for the prolonging effects of IOT in relation to rehospitalization and the reduction of rehospitalization risk compared to patients with schizophrenia who receive GOT alone, in addition to supporting good cognition at discharge and favorable medication adherence.

The Usefulness of Posterior Shiny Corner Lesions in the Early Diagnosis of Medial Meniscus Posterior Root Tears.

INTRODUCTION:  Posterior shiny corner lesions (PSCLs) have been reported to be useful for the early diagnosis of medial meniscus posterior root tears (MMPRTs) in surgical patients. However, the usefulness of PSCLs in outpatients, particularly regarding the optimal timing of magnetic resonance imaging (MRI) examinations after injury, remains unknown. We hypothesized that PSCLs would normally be observed in patients with MMPRTs within one month of injury. MATERIALS AND METHODS:  This study included 144 patients with knee pain who visited our hospital between January 2021 and May 2023. MRI findings within and after one month were examined. Fisher's exact test was performed for PSCLs, cleft signs, ghost signs, radial tear signs, bone cysts, and medial meniscus extrusion (MME), which are findings used for the diagnosis of MMPRTs. Time-dependent receiver operating characteristic (ROC) curve analysis was performed for each MRI finding. A binomial logistic regression analysis was performed for age, sex, PSCL, ghost sign, and MME. RESULTS: PSCLs were observed on 82.6% of the MRI scans within one month, but the positivity rate decreased after one month. After one month, a high percentage of patients had cleft signs and ghost signs. The results of a time-dependent ROC curve analysis showed that the PSCL had better diagnostic ability than the cleft sign, ghost sign, radial tear sign, and MME at a relatively early stage. Additionally, the area under the curve (AUC) of PSCL peaks around 35 days and then declines, reaching 0.8 or less around 40 days. On the other hand, the AUC of the cleft sign and ghost sign began to increase around 30 days after injury, and it exceeded 0.8 after approximately 100 days. The results of the binomial logistic regression analysis revealed significant PSCLs and ghost signs. Independent associations between the PSCL, or ghost sign, and the MMPRT were demonstrated. CONCLUSION:  This study suggests that PSCLs have a superior diagnostic capability for MMPRT during the early stages of injury compared with other MRI findings in outpatients. In particular, PSCLs have a high positivity rate within one month after injury and a high diagnostic capacity up to 40 days after injury.

Effect of individualized occupational therapy on cognition among patients with schizophrenia: A randomized controlled trial.

This study aimed to evaluate the feasibility and efficacy of individualized occupational therapy (IOT) plus group occupational therapy (GOT) as standard care for cognition compared to GOT alone, and to determine which IOT component has the greatest effect on cognitive outcome in patients with schizophrenia. This study was conducted at 14 clinical sites across Japan and enrolled recently hospitalized patients with schizophrenia. The IOT consisted of motivational interview, self-monitoring, individualized visits, craft activities, individualized psychoeducation, and discharge planning. Among the 68 patients who were randomized to the GOT + IOT group (n = 34) and GOT alone group (n = 34), 67 completed the trial (GOT + IOT group, n = 34; GOT alone group, n = 33). There were significant improvements in change from baseline to post-treatment between the groups in verbal memory, working memory, verbal fluency, attention, executive function domains, and the composite score of the Brief Assessment of Cognition in Schizophrenia (BACS). The BACS composite score was significantly associated with the number of craft activity sessions. The addition of IOT to GOT has a favorable feasibility profile and efficacy for cognition in schizophrenia. Craft activity is the most effective IOT component in improving cognition.

Postoperative Medial Tilting of the Joint Line and Preoperative Kinematics Influence Postoperative Medial Pivot Pattern Reproduction in Total Knee Arthroplasty.

Background: Reproducing the medial pivot pattern after total knee arthroplasty (TKA) is known to improve patient satisfaction. However, the factors affecting the postoperative medial pivot pattern in TKA are controversial. The purpose of this study was to examine the factors affecting the postoperative medial pivot pattern in posterior-stabilized TKA. Methods: This study involved 30 cases with knee osteoarthritis who underwent primary posterior-stabilized TKA. The preoperative and postoperative kinematics were measured using a computed tomography-free navigation system, and the patients were divided into the following 2 groups: the medial pivot pattern (MP) group and non-medial pivot pattern (non-MP) group. In addition, we measured each of the following angles on X-ray films (preoperative and postoperative femorotibial angle, hip-knee-ankle angle, mechanical lateral distal femoral angle, medial proximal tibial angle). We examine the factors affecting the postoperative medial pivot pattern. Results: There were 14 cases in the MP group and 16 cases in the non-MP group at the preoperative knee kinematic assessment and 17 cases in the MP group and 13 cases in the non-MP group at the postoperative knee kinematic assessment. The preoperative kinematic pattern was conserved after the surgery at a rate of 76.7%. The postoperative MP-group showed a significantly smaller preoperative femorotibial angle and hip-knee-ankle and a significantly smaller postoperative mechanical lateral distal femoral angle and medial proximal tibial angle in comparison to the postoperative non-MP group. Conclusions: Preoperative kinematics and postoperative mechanical lateral distal femoral angle and medial proximal tibial angle may be important factors that affect the postoperative medial pivot pattern.

Reliability and validity of the Nepean Beliefs Scale for delusions and overvalued ideas in chronic schizophrenia: analysis of a preliminary pilot study.

Introduction: The Nepean Beliefs Scale by Brakoulias et al. is an interview-based multidimensional instrument that measures pathological beliefs in various psychiatric disorders. This study examined the reliability and validity of Nepean Beliefs Scale (NBS) for delusions and overvalued ideas in patients with chronic-phase schizophrenia. Methods: Multiple raters at two healthcare settings examined the beliefs of 28 individuals with schizophrenia using the NBS. Concurrently, PANSS, PDI-21, BCIS, PHQ-9 and GAD-7 were administered. Results: The NBS had high reliability and correlation with relevant scales. Discussion: The NBS was found to have sufficient reliability and validity for assessing the pathological beliefs of patients with chronic schizophrenia. Although NBS is an easy-to-instruct instrument, it should be noted that appropriate explanations and examples should be added to instructions to obtain reliable responses from patients with chronic schizophrenia.

A simplified method to generate serotonergic neurons from mouse embryonic stem and induced pluripotent stem cells.

We have developed a new simple method to induce serotonergic neurons from embryonic stem (ES) and induced pluripotent stem cells. When ES or induced pluripotent stem cells were cultured on a thick gel layer of Matrigel, most colonies extended TuJ1-positive neurites. We found that noggin, a known antagonist of bone morphogenic protein, induces ES cells to express genes involved in serotonergic differentiation, such as Nkx2.2, Pet-1, Sonic hedgehog, tryptophan hydroxylase 2, and serotonin transporter, as well as increases high potassium-induced release of serotonin. To concentrate serotonergic neurons, ES cells carrying Pet-1-enhancer-driven enhanced green fluorescent protein were differentiated and sorted into about 80% pure cultures of serotonergic neurons. Whole cell voltage-clamp recordings showed a voltage-dependent current in dissociated neurons. This simplified method provides an alternative option for serotonergic differentiation of pluripotent stem cells and will likely contribute a deeper understanding regarding the nature of serotonergic neurons and open new therapeutic perspectives for the treatment of psychiatric disorders.

Aerobic exercise and cognitive functioning in schizophrenia: An updated systematic review and meta-analysis.

This study serves as an update to a recent systematic review and meta-analysis to summarize the effect of aerobic exercise on cognition in schizophrenia and determine the most effective method of aerobic exercise. We searched for controlled studies investigating the effect of aerobic exercise on cognition in schizophrenia published until January 2021. Fifteen studies were included. A random-effects model was used to estimate the standardized mean differences (SMDs) between cognitive outcomes of aerobic exercises and controls. Compared with controls, aerobic exercises resulted in significant improvements in global cognition (SMD = 0.21), attention/vigilance (SMD = 0.32), working memory (SMD = 0.27), and verbal learning (SMD = 0.30). Significant improvements in global cognition were observed with group exercise (SMD = 0.28), exercise supervised by exercise professionals (SMD = 0.27), as well as with ≥ 90 min/week (SMD = 0.26) and ≥ 12 weeks duration (SMD = 0.22). Our findings provide information beneficial for determining the most effective aerobic exercise method to improve cognition in schizophrenia.

Effect of individualized occupational therapy on social functioning in patients with schizophrenia: A five-year follow-up of a randomized controlled trial.

This study aimed to evaluate the long-term effects of adding individualized occupational therapy (IOT) to a three-months group occupational therapy (GOT) on social functioning in inpatients with schizophrenia or schizoaffective disorder at a follow-up investigation five-years after discharge. Initially, patients were randomly assigned to GOT + IOT or GOT alone, with 102 patients, 48 in GOT + IOT and 54 in GOT alone, completing the five years follow-up. The primary outcome was change in social functioning assessed by the Social Functioning Scale (SFS) from baseline to five-year follow-up. Other outcomes included Brief Assessment of Cognition in Schizophrenia (BACS), Schizophrenia Cognition Rating Scale (SCoRS), Intrinsic Motivation Inventory (IMI), Global Assessment of Functioning (GAF), Positive and Negative Syndrome Scale (PANSS), and Client Satisfaction Questionnaire-8 (CSQ-8). There were significant improvements for the GOT + IOT group over GOT in the SFS total score, which could be explained by improvements in withdrawal/social engagement, interpersonal communication, pro-social activities, recreation, and independence-competence. Multiple regression analysis showed that the period from hospitalization to commencing occupational therapy, type of occupational therapy, BACS motor speed, BACS executive function, and IMI interest/enjoyment were significantly associated with SFS total score. Our findings suggest that adding IOT to GOT may improve the long-term outcome on social functioning in schizophrenic patients. However, the long time period between intervention and follow-up and the unavailability of treatment information during the follow-up period has to be mentioned as a limiting factor of this study.

Calcium/calmodulin-dependent protein kinase IIα heterozygous knockout mice show electroencephalogram and behavioral changes characteristic of a subpopulation of schizophrenia and intellectual impairment.

Cognitive deficit remains an intractable symptom of schizophrenia, accounting for substantial disability. Despite this, little is known about the cause of cognitive dysfunction in schizophrenia. Recent studies suggest that schizophrenia patients show several changes in dentate gyrus structure and functional characteristic of immaturity. The immature dentate gyrus (iDG) has been replicated in several mouse models, most notably the CaMKIIα heterozygous mouse (CaMKIIα-hKO). The current study characterizes behavioral phenotypes of CaMKIIα-hKO mice and determines their neurophysiological profile using electroencephalogram (EEG) recording from hippocampus. CaMKIIα-hKO mice were hypoactive in home-cage environment; however, they displayed less anxiety-like phenotype, suggestive of impulsivity-like behavior. In addition, severe cognitive dysfunction was evident in CaMKIIα-hKO mice as examined by novel object recognition and contextual fear conditioning. Several EEG phenomena established in both patients and relevant animal models indicate key pathological changes associated with the disease, include auditory event-related potentials and time-frequency EEG oscillations. CaMKIIα-hKO mice showed altered event-related potentials characterized by an increase in amplitude of the N40 and P80, as well as increased P80 latency. These mice also showed increased power in theta range time-frequency measures. Additionally, CaMKIIα-hKO mice showed spontaneous bursts of spike wave activity, possibly indicating absence seizures. The GABAB agonist baclofen increased, while the GABAB antagonist CGP35348 and the T-Type Ca2+ channel blocker Ethosuximide decreased spike wave burst frequency. None of these changes in event-related potentials or EEG oscillations are characteristic of those observed in general population of patients with schizophrenia; yet, CaMKIIα-hKO mice likely model a subpopulation of patients with schizophrenia.

Aerobic exercise and cognitive functioning in schizophrenia: Results of a 1-year follow-up from a randomized controlled trial.

We previously reported that adding combined, individual, and group aerobic exercise (AE) interventions to the treatment as usual (TAU) for schizophrenia showed significant improvements in cognition and other outcomes compared to those with TAU alone in a randomized controlled trial. Following the promising results of our previous study, this 1-year follow-up study evaluated the improvements in cognition and other outcomes with TAU + AE compared to those with TAU alone. Of 41 randomized patients, 40 were included in the intent-to-treat population-20 in the TAU + AE and 20 in the TAU alone; all patients completed the 1-year follow-up. Mixed models were applied to assess changes in outcome measures over time from baseline to 1-year follow-up. At 1-year follow-up, the TAU + AE demonstrated significant group by time interaction effects in several cognitive domains, intrinsic motivation, negative symptom, interpersonal relations, and functional outcome compared with the TAU alone. Our results demonstrate that the improvements in cognition and other outcomes with TAU + AE were maintained and that functional outcome improved over 1-year follow-up. These findings show that the improvements sustained for each outcome over 1 year have the potential to offer opportunities for greater transitions to improvement of functional outcome.

The efficacy of extended metacognitive training for psychosis: A randomized controlled trial.

This study investigated the efficacy of 10-module metacognitive training (MCT) among Japanese patients with schizophrenia by conducting a multicenter randomized controlled trial to test the influence of the most recent and extended version of MCT on positive symptoms. A six-center, randomized, assessor-blind, controlled trial between "treatment as usual" (TAU) and TAU + MCT was conducted. Fifty inpatients and outpatients with schizophrenia, schizotypal, and delusional disorders (ICD 10) were enrolled, then randomly assigned to TAU (n = 26) or TAU + MCT (n = 24). Assessments were made at baseline, after six weeks, immediately posttreatment, and 1-month post-treatment. The primary outcome was positive symptom score, as measured by the Positive and Negative Syndrome Scale (PANSS). General assessment of functioning (GAF) and measures of cognitive biases were secondary outcomes. Completion at post-treatment (10 weeks later) and 1-month follow-up was high-TAU + MCT, n = 22 (91.67%) and TAU, n = 23 (88.46%). The severity of PANSS positive symptoms declined significantly in the TAU + MCT treatment group compared with the TAU group. GAF also showed significantly greater improvement in the TAU + MCT group compared with the TAU group. There was also a trend for greater efficacy of MCT on cognitive biases. In conclusion, this study provides support for the efficacy of 10 module MCT concerning positive symptomatology (especially, delusion) and general functioning.

Aerobic exercise and cognitive functioning in schizophrenia: A pilot randomized controlled trial.

This pilot randomized controlled trial evaluated the combined effect of individual and group aerobic exercises (AEs) on cognition in schizophrenia. Among 32 randomized patients, 31 were included in the intent-to-treat population: 16 in treatment as usual (TAU) + AE and 15 in TAU groups. Over 12 weeks, patients were given a dose of 2 exercise sessions per week, including 1 individual session and 1 group session. TAU + AE patients showed significant improvements in cognition, intrinsic motivation, psychiatric symptoms, and interpersonal relations. These encouraging findings support the promise of integrated individual and group AEs to improve cognition and other outcomes in schizophrenia.

Polymorphisms in the IDE-KIF11-HHEX gene locus are reproducibly associated with type 2 diabetes in a Japanese population.

CONTEXT: A genome-wide association study in the French population has detected that novel single-nucleotide polymorphisms (SNPs) in the IDE-KIF11-HHEX gene locus and the SLC30A8 gene locus are associated with susceptibility to type 2 diabetes. OBJECTIVE: We investigated whether SNPs in these loci were associated with type 2 diabetes in Japanese. DESIGN: Two SNPs, rs7923837 and rs1111875, in the IDE-KIF11-HHEX gene locus and one SNP, rs13266634, in the SLC30A8 gene locus were genotyped in Japanese type 2 diabetic patients (n = 405) and in nondiabetic control subjects (n = 340) using the TaqMan genotyping assay system. RESULTS: The G allele of rs7923837 was associated with type 2 diabetes [odds ratio 1.66, 95% confidence interval (CI) 1.28-2.15; P = 0.00014], following the same tendency as in the French population of the previous report. Heterozygous and homozygous carriers of the risk allele had odds ratios of 1.57 (95% CI 1.15-2.16; P = 0.0050) and 3.16 (95% CI 1.40-7.16; P = 0.0038) relative to noncarriers. Although the G allele was a major allele (66.5%) in the French population, it was a minor allele (23.8%) in Japanese. The G allele of rs1111875 was also associated with type 2 diabetes (odds ratio 1.42, 95% CI 1.13-1.78; P = 0.0024). Heterozygous and homozygous carriers of the risk allele had odds ratios of 1.31 (95% CI 0.97-1.77; P = 0.0810) and 2.40 (95% CI 1.34-4.32; P = 0.0028) relative to noncarriers. A significant association with type 2 diabetes was not observed for rs13266634. CONCLUSIONS: Polymorphisms in the IDE-KIF11-HHEX gene locus are associated with susceptibility to type 2 diabetes across the boundary of race.

Correction: A multicenter, randomized controlled trial of individualized occupational therapy for patients with schizophrenia in Japan.

[This corrects the article DOI: 10.1371/journal.pone.0193869.].

A multicenter, randomized controlled trial of individualized occupational therapy for patients with schizophrenia in Japan.

The individualized occupational therapy (IOT) program is a psychosocial program that we developed to facilitate proactive participation in treatment and improve cognitive functioning and other outcomes for inpatients with acute schizophrenia. The program consists of motivational interviewing, self-monitoring, individualized visits, handicraft activities, individualized psychoeducation, and discharge planning. This multicenter, open-labeled, blinded-endpoint, randomized controlled trial evaluated the impact of adding IOT to a group OT (GOT) program as usual for outcomes in recently hospitalized patients with schizophrenia in Japanese psychiatric hospitals setting compared with GOT alone. Patients with schizophrenia were randomly assigned to the GOT+IOT group or the GOT alone group. Among 136 randomized patients, 129 were included in the intent-to-treat population: 66 in the GOT+IOT and 63 in the GOT alone groups. Outcomes were administered at baseline and discharge or 3 months following hospitalization including the Brief Assessment of Cognition in Schizophrenia Japanese version (BACS-J), the Schizophrenia Cognition Rating Scale Japanese version, the Social Functioning Scale Japanese version, the Global Assessment of Functioning scale, the Intrinsic Motivation Inventory Japanese version (IMI-J), the Morisky Medication Adherence Scale-8 (MMAS-8), the Positive and Negative Syndrome Scale (PANSS), and the Japanese version of Client Satisfaction Questionnaire-8 (CSQ-8J). Results of linear mixed effects models indicated that the IOT+GOT showed significant improvements in verbal memory (p <0.01), working memory (p = 0.02), verbal fluency (p < 0.01), attention (p < 0.01), and composite score (p < 0.01) on the BACS-J; interest/enjoyment (p < 0.01), value/usefulness (p < 0.01), perceived choice (p < 0.01), and IMI-J total (p < 0.01) on the IMI-J; MMAS-8 score (p < 0.01) compared with the GOT alone. Patients in the GOT+IOT demonstrated significant improvements on the CSQ-8J compared with the GOT alone (p < 0.01). The present findings provide support for the feasibility in implementing an IOT program and its effectiveness for improving cognitive impairment and other outcomes in patients with schizophrenia.

Psychostimulant-induced attenuation of hyperactivity and prepulse inhibition deficits in Adcyap1-deficient mice.

Psychostimulants, including amphetamine, act as antihyperkinetic agents in humans with hyperkinetic disorder such as attention-deficit hyperactivity disorder and are known to be effective in enhancing attention-related processes; however, the underlying mechanisms have not been adequately addressed. Mice lacking the Adcyap1 gene encoding the neuropeptide pituitary adenylate cyclase-activating polypeptide (Adcyap1(-/-)) display psychomotor abnormalities, including increased novelty-seeking behavior and hyperactivity. In this study, Adcyap1(-/-) mice showed sensory-motor gating deficits, measured as deficits in prepulse inhibition (PPI), and showed normal PPI in response to amphetamine. Amphetamine also significantly decreased hyperlocomotion in Adcyap1(-/-) mice, and this paradoxical antihyperkinetic effect depended on serotonin 1A (5-HT(1A)) receptor signaling. c-Fos-positive neurons were increased in the prefrontal cortex in amphetamine-treated Adcyap1(-/-) mice, suggesting increased inhibitory control by prefrontal neurons. Additionally, amphetamine produced an antihyperkinetic effect in wild-type mice that received the 5-HT(1A) agonist 8-hydroxy-2-(di-n-propylamino)tetralin. These results indicate that Adcyap1(-/-) mice act as a model of hyperlocomotion and PPI deficits and suggest that 5-HT(1A)-mediated pathways are important determinants of the psychostimulant-elicited, rate-dependent effects that are in a negative function of the baseline rate of activity.

Simple and selective sensing of cysteine using gold nanoparticles conjugated with a thermoresponsive copolymer having carboxyl groups.

We describe a simple, yet selective cysteine sensor based on gold nanoparticles (AuNPs) conjugated with thermoresponsive copolymers, the carboxyl groups of which are incorporated. Copolymer-conjugated AuNPs, used as the cysteine sensor, in a solution form sediment when cysteine is added. Heating followed by cooling the solution induces phase transitions of the thermoresponsive copolymers, resulting in an acceleration of sedimentation of the copolymer-conjugated AuNPs. The absorbance of supernatants at 520 nm, which are ascribed to a surface plasmon band of discrete AuNPs, decays with increasing concentration of cysteine. Sedimentation of the copolymer-conjugated AuNPs is specific to cysteine. The addition of other popular amino acids, or ascorbic acid, causes no sedimentation of the AuNPs. The relationship between the absorbance of the supernatant at 520 nm and the cysteine concentration provides a sigmoidal profile at a concentration range between 1 x 10(-6) to 6 x 10(-6) mol dm(-3). The determination of cysteine in a supplement is achieved using an inflection point on the sigmoidal profiles.

Inhibition of self-renewal and induction of neural differentiation by PACAP in neural progenitor cells.

Several lines of evidence have suggested roles for pituitary adenylate cyclase-activating polypeptide (PACAP) in the developing nervous system. Previously, we showed that mRNA for PACAP, vasoactive intestinal peptide (VIP), and their three receptor subtypes, is differentially expressed in embryonic stem (ES) cells, ES cell-derived, neural stem cell-enriched cultures, and differentiated neurons, by using the five steps of the in vitro neuronal culture model of ES cell differentiation. Here, we examined the effects of PACAP on self-renewal and cell lineage determination of neural progenitor/stem cells. PACAP inhibited the basic fibroblast growth factor-induced proliferation (self-renewal), as assessed by neurosphere formation. PACAP increased microtubule-associated protein 2-positive neurons without affecting the number of cells positive for the neural stem cell marker nestin, astrocyte marker glial fibrillary acidic protein, and oligodendrocyte marker CNPase. These results suggest that PACAP inhibits self-renewal but, instead, induces early neuronal differentiation of neural progenitor cells.

Fourier transform infrared spectroscopic analysis of the intact zona pellucida of the mammalian egg: changes in the secondary structure of bovine zona pellucida proteins during fertilization.

The zona pellucida is the acellular transparent envelope surrounding the mammalian oocyte. An analysis of the changes in the structures of zona pellucida proteins is essential for understanding the molecular mechanisms underlying the important physiological roles of the zona during fertilization and preimplantation. The hardening of the zona caused by the structural changes during fertilization is generally accepted to be responsible for blocking polyspermy. In this study, we analyzed changes in the secondary structure of the zona during fertilization by Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy. The predominance of beta-sheet structure in porcine ovarian egg zona proteins in water was ascertained using FTIR spectra. Alpha-helix structure was also present. The attenuated total reflection (ATR)-FTIR spectrum of intact, unsolubilized porcine zonae pellucidae from ovarian eggs indicated that the zona proteins in the native zona pellucida also have beta-structure as the main constituent. Attenuated total reflection-FTIR spectroscopy of intact bovine zona pellucida obtained from ovarian and fertilized eggs at the blastocyst stage revealed that the beta-structure content increased during fertilization. Furthermore, a reduction of the thickness of the zona during fertilization was observed using transmission electron microscopy. Therefore, the change in the zona architecture that causes hardening of the zona during fertilization is accompanied by changes in the secondary structure of the zona proteins.