Serum undercarboxylated osteocalcin level increases with 48 weeks of teriparatide treatment in pre-treated elderly rheumatoid arthritis patients who use anti-resorptive drugs

AIM

The serum undercarboxylated osteocalcin (ucOC) level, a biochemical bone marker of vitamin K insufficiency, is often affected by anti-osteoporosis drugs. There have been no reports regarding the relationship between ucOC and teriparatide.

SUBJECTS AND METHODS

We conducted a prospective observational study of 26 female rheumatoid arthritis (RA) patients. The patients were divided into 3 groups: those who underwent a direct switch from anti-resorptive drugs to teriparatide (12 cases), those who started teriparatide without pre-treatment (5 cases), and the control patients (9 cases). The median age (interquartile range) of the patients in each group was 75 (67-77), 82 (78-84), and 69 (62-80) yr, respectively. All patients, except controls, received 48-week treatments of teriparatide. We analyzed the median 48-week changes from baseline of the serum ucOC levels with the Steel-Dwass method.

RESULTS

The median change from baseline in the direct switch group was higher than that in other groups (p<0.05).

CONCLUSIONS

The serum ucOC levels increased with treatment of teriparatide in elderly RA patients, especially when the patients received pre-treatment.

Positive outcome of average volume-assured pressure support mode of a Respironics V60 Ventilator in acute exacerbation of chronic obstructive pulmonary disease: a case report

INTRODUCTION

We were able to treat a patient with acute exacerbation of chronic obstructive pulmonary disease who also suffered from sleep-disordered breathing by using the average volume-assured pressure support mode of a Respironics V60 Ventilator (Philips Respironics: United States). This allows a target tidal volume to be set based on automatic changes in inspiratory positive airway pressure. This removed the need to change the noninvasive positive pressure ventilation settings during the day and during sleep. The Respironics V60 Ventilator, in the average volume-assured pressure support mode, was attached to our patient and improved and stabilized his sleep-related hypoventilation by automatically adjusting force to within an acceptable range.

CASE PRESENTATION

Our patient was a 74-year-old Japanese man who was hospitalized for treatment due to worsening of dyspnea and hypoxemia. He was diagnosed with acute exacerbation of chronic obstructive pulmonary disease and full-time biphasic positive airway pressure support ventilation was initiated. Our patient was temporarily provided with portable noninvasive positive pressure ventilation at night-time following an improvement in his condition, but his chronic obstructive pulmonary disease again worsened due to the recurrence of a respiratory infection. During the initial exacerbation, his tidal volume was significantly lower during sleep (378.9 ± 72.9mL) than while awake (446.5 ± 63.3mL). A ventilator that allows ventilation to be maintained by automatically adjusting the inspiratory force to within an acceptable range was attached in average volume-assured pressure support mode, improving his sleep-related hypoventilation, which is often associated with the use of the Respironics V60 Ventilator. Polysomnography performed while our patient was on noninvasive positive pressure ventilation revealed obstructive sleep apnea syndrome (apnea-hypopnea index = 14), suggesting that his chronic obstructive pulmonary disease was complicated by obstructive sleep apnea syndrome.

CONCLUSION

In cases such as this, in which patients with severe acute respiratory failure requiring full-time noninvasive positive pressure ventilation therapy also show sleep-disordered breathing, different ventilator settings must be used for waking and sleeping. On such occasions, the Respironics V60 Ventilator, which is equipped with an average volume-assured pressure support mode, may be useful in improving gas exchange and may achieve good patient compliance, because that mode allows ventilation to be maintained by automatically adjusting the inspiratory force to within an acceptable range whenever ventilation falls below target levels.

Surface Andreev bound states of superfluid 3He and Majorana fermions

Superfluid (3)He is an intensively investigated and well characterized p-wave superfluid. In the bulk Balian-Werthamer state, which is commonly called the (3)He B phase, the superfluid gap is opened isotropically but near a flat boundary such as a wall of a container it can harbor interesting quasi-particle states inside the gap. These states are called surface Andreev bound states, and have not been experimentally explored in detail. Transverse acoustic impedance measurement has revealed their existence and provided spectroscopic details of the dispersion of the bound states. Recent theoretical arguments claim that the surface Andreev bound states of the superfluid (3)He B phase can be recognized as the edge states of the topological superfluid and be regarded as a Majorana fermion, a fancy particle which has not been confirmed in elementary particle physics. In this review, we present up-to-date knowledge on the surface Andreev bound states of the (3)He B phase revealed by acoustic spectroscopy and the possible realization of a Majorana fermion, along with related studies on this topic.

Post-menopausal women with rheumatoid arthritis who are treated with raloxifene or alendronate or glucocorticoids have lower serum undercarboxylated osteocalcin levels

BACKGROUND

Serum undercarboxylated osteocalcin (ucOC) is a biochemical bone marker of vitamin K insufficiency. It had been reported that bone resorption inhibitors tend to decrease the serum ucOC level in patients with primary osteoporosis. In rheumatoid arthritis (RA) patients, these results have never been reported.

AIM

We investigated risk factors which could change serum ucOC level in post-menopausal women with RA (no.=100).

SUBJECTS AND METHODS

Twenty patients received no bone resorption inhibitor (control), 30 received raloxifene (RLX), while 50 received alendronate (ALN). This cross-sectional study was limited to patients with low RA disease activity (Disease Activity Score-28 ≤3.2). We measured serum ucOC, and the data were analyzed by multivariable analysis, including ucOC and the other variables.

RESULTS

Scheffe's F test demonstrated a significant difference in serum ucOC levels between controls and the RLX group (p<0.01), and between controls and the ALN group (p<0.01). Serum ucOC levels were low in both treated groups. An adjusted multivariate analysis was performed for the variables: bone resorption inhibitor use, serum alkaline phosphatase, glucocorticoid dose, age, estimated glomerular filtration rate and matrix metalloproteinase 3. As a result, serum ucOC inversely correlated with bone resorption inhibitor use (p<0.01) and oral glucocorticoid dose (p<0.01), which were independent risk factors of lowering ucOC.

CONCLUSIONS

Bone resorption inhibitors and glucocorticoids were independent risk factors for lowering serum ucOC levels in post-menopausal RA patients.

Strong suppression of the Kosterlitz-Thouless transition in a 4He film under high pressure

We have found that the surface specularity for 3He quasiparticle scattering is closely related to the superfluidity and the Kosterlitz-Thouless (KT) transition of 4He film adsorbed on the surface. The specularity is determined by measurements of the transverse acoustic impedance of bulk liquid 3He. The unique point of our system is that we can control the correlation among 4He atoms in the film by changing the pressure of the bulk 3He. The observed KT transition temperature is significantly suppressed by increasing the pressure, which suggests a strong correlation effect on KT transition.

Porcine circovirus type 2 potentiates morbidity of Salmonella enterica serovar Choleraesuis in Cesarean-derived, colostrum-deprived pigs

PROBLEM ADDRESSED

Porcine circovirus type 2 (PCV2) and Salmonella enterica subspecies enterica serovar Choleraesuis (S. Choleraesuis) are two leading causes of economic loss in the swine industry. Although S. Choleraesuis infection occurs concurrently with PCV2-associated disease in many swine herds, the pathogenesis of concurrent infection with PCV2 and S. Choleraesuis remains largely undefined.

OBJECTIVE

We investigated the interactions between PCV2 and S. Choleraesuis in 20 Cesarean-derived, colostrum-deprived (CDCD) pigs randomly assigned to 4 groups (n=5 per group).

METHODS AND APPROACH

Pigs in the dual-infected and PCV2-infected groups were inoculated intranasally with PCV2 at 5 weeks of age, and pigs in the dual-infected and S. Choleraesuis-infected groups were inoculated intranasally with S. Choleraesuis at 7 weeks of age. Pigs in the control group served as uninfected controls.

RESULTS

After S. Choleraesuis inoculation, severe clinical signs, reduction of weight gain, and severe microscopic lung lesions were observed in dual-infected pigs compared to those in other groups. In addition, the pigs in the dual-infected group shed significantly (P=0.002) higher quantities of S. Choleraesuis in feces 12 days after S. Choleraesuis inoculation, and S. Choleraesuis was recovered from more tissues in this group 14 days after S. Choleraesuis inoculation.

CONCLUSIONS

These results indicate that prior PCV2 infection potentiates the severity of clinical signs, lung lesions, and fecal shedding and tissue dissemination of S. Choleraesuis in infected pigs. Therefore, dual infection of pigs with PCV2 and S. Choleraesuis may increase clinical effects of salmonellosis in the field.

Activity of retreatment with sorafenib for metastatic renal cell carcinoma

404

Background: Treatment options for metastatic renal cell carcinoma (mRCC) have increased. Complete remission is, however, rarely seen and patients are treated with multiple sequential therapies. We assessed clinical activity of sorafenib rechallenge after progressing on other therapies.

Methods: Patients with mRCC who received a second course of sorafenib therapy after failure of prior sorafenib and other agents were retrospectively identified. RECIST-defined objective response rate and progression-free survival (PFS) and toxicity were analyzed.

Results: Fourteen patients with mRCC who were retreated with sorafenib were identified and twelve patients were assessable for this study. 92% were male. Median age at first systemic therapy was 63 years. Prior nephrectomy was performed in 92% of patients. 42% of patients had favorable or intermediate risk, 17% poor, and the rest not available per MSKCC criteria. Eighty-three percent of patients were treated with other agents before initial sorafenib therapy, including 75% interferon-alpha (IFN-alpha), 50% interleukin-2 (IL-2), and 17% sunitinib. First sorafenib therapy began a median of 9.0 months after the diagnosis of mRCC and produced a clinical benefit (PR + SD) rate of 75% and a median PFS of 5.0 months. 67% of patients discontinued initial sorafenib for disease progression and 33% for adverse events. Interval between discontinuation of initial sorafenib and rechallenge was a median of 7.6 months. During the intervening period, 50% of patients were treated with sunitinib, 33% with everolimus, 25% with VEGFR1 vaccine, and others. Clinical benefit rate of 67% and a median PFS of 4.3 months were obtained on sorafenib rechallenge. There was no significant difference in outcome to sorafenib rechallenge based on duration between sorafenib treatments or number or type of intervening treatments. No new severe toxicity was observed during rechallenge.

Conclusions: Sorafenib rechallenge has potential to achieve clinical benefits, is well-tolerated, and may be considered after multiple sequential therapies in select mRCC patients.

No significant financial relationships to disclose.

Increases in discontinuous rib cartilage and fused carpal bone in rat fetuses exposed to the teratogens, busulfan, acetazolamide, vitamin A, and ketoconazole

Skeletal changes induced by treatment of pregnant rats with four potent teratogens, busulfan, acetazolamide, vitamin A palmitate, and ketoconazole, were evaluated using Alizarin Red S and Alcian Blue double-staining to investigate the relationship between drug-induced skeletal malformations and cartilaginous changes in the fetuses. Pregnant rats (N = 8/group) were treated once or twice between gestation days (GDs) 10 to 13 with busulfan at doses of 3, 10, or 30 mg/kg; acetazolamide at 200, 400, or 800 mg/kg; vitamin A palmitate at 100,000, 300,000, or 1,000,000 IU/kg; or ketoconazole at doses of 10, 30, or 100 mg/kg. Uterine evaluations and fetal external and skeletal examinations were conducted on GD 20. Marked skeletal abnormalities in ribs and hand/forelimb bones such as absent/ short/bent ribs, fused rib cartilage, absent/fused forepaw phalanx, and misshapen carpal bones were induced at the mid- and high-doses of busulfan and acetazolamide and at the high-dose of vitamin A palmitate and ketoconazole. Increased incidences of discontinuous rib cartilage (DRC) and fused carpal bone (FCB) were observed from the low- or mid-dose in the busulfan and acetazolamide groups, and incidences of FCB were increased from the mid-dose in the vitamin A palmitate and ketoconazole groups. Therefore, DRC and FCB were detected at lower doses than those at which ribs and hand/forelimb malformations were observed in the four potent teratogens.

New anomaly in the transverse acoustic impedance of superfluid 3He-B with a wall coated by several layers of 4He

We measured the transverse acoustic impedance of superfluid 3He-B with a wall coated by several layers of 4He. The coating is known to enhance the specularity in quasiparticle scattering by the wall. We found a new anomaly, a bump and a peak, in the temperature dependence of the transverse acoustic impedance. This agrees with a theoretical calculation using a partially specular wall boundary condition. The new anomaly is shown to arise from a change in the surface density of states by coating and the scattering of thermally occupied surface bound states to other states. The change is towards the density of states of Majorana cone in the specular limit.

A new formulation for orally disintegrating tablets using a suspension spray-coating method

The aim of this study was to design a new orally disintegrating tablet (ODT) that has high tablet hardness and a fast oral disintegration rate using a new preparation method. To obtain rapid disintegration granules (RDGs), a saccharide, such as trehalose, mannitol, or lactose, was spray-coated with a suspension of corn starch using a fluidized-bed granulator (suspension method). As an additional disintegrant, crospovidone, light anhydrous silicic acid, or hydroxypropyl starch was also included in the suspension. The RDGs obtained possessed extremely large surface areas, narrow particle size distribution, and numerous micro-pores. When tabletting these RDGs, it was found that the RDGs increased tablet hardness by decreasing plastic deformation and increasing the contact frequency between granules. In all tablets, a linear relationship was observed between tablet hardness and oral disintegration time. From each linear correlation line, a slope (D/H value) and an intercept (D/H(0) value) were calculated. Tablets with small D/H and D/H(0) values could disintegrate immediately in the oral cavity regardless of the tablet hardness and were considered to be appropriate for ODTs. Therefore, these values were used as key parameters to select better ODTs. Of all the RDGs prepared in this study, mannitol spray-coated with a suspension of corn starch and crospovidone (2.5:1 w/w ratio) showed most appropriate properties for ODTs; fast in vivo oral disintegration time, and high tablet hardness. In conclusion, this simple method to prepare superior formulations for new ODTs was established by spray-coating mannitol with a suspension of appropriate disintegrants.

Rapid improvement of massive bloody pleural effusion after splenectomy for splenic marginal zone lymphoma

Splenic marginal zone lymphoma (SMZL) is a rare malignant lymphoma involving marginal zone B cells, accounting for only 1% of non-Hodgkin lymphomas. No previous reports have documented SMZL accompanied by massive bloody pleural effusion. Herein, the case of a patient with SMZL that was only diagnosed after splenectomy and thoracoscopic pleural biopsy is presented. SMZL in this patient was accompanied by massive bloody pleural effusion. The characteristics of the patient's pleural effusion changed from bloody to transudative after splenectomy, and rapid improvement was observed. It was considered that the splenectomy was valid for treatment of unidentified pleural effusion with enlarged spleen.

Enhancement of superconducting transition temperature due to the strong antiferromagnetic spin fluctuations in the noncentrosymmetric heavy-fermion superconductor CeIrSi3: A 29Si NMR study under pressure

We report a (29)Si NMR study on the pressure-induced superconductivity (SC) in an antiferromagnetic (AFM) heavy-fermion compound CeIrSi(3) without inversion symmetry. In the SC state at P = 2.7-2.8 GPa, the temperature (T) dependence of the nuclear-spin lattice relaxation rate 1/T(1) below T(c) exhibits a T(3) behavior without any coherence peak just below T(c), revealing the presence of line nodes in the SC gap. In the normal state, 1/T(1) follows a square root T-like behavior, suggesting that the SC emerges under the non-Fermi-liquid state dominated by AFM spin fluctuations enhanced around a quantum critical point. The reason why the maximum T(c) in CeIrSi(3) is relatively high among the Ce-based heavy-fermion superconductors may be the existence of the strong AFM spin fluctuations. We discuss the comparison with the other Ce-based heavy-fermion superconductors.

Pentax-AWS, a new videolaryngoscope, is more effective than the Macintosh laryngoscope for tracheal intubation in patients with restricted neck movements: a randomized comparative study

BACKGROUND

We studied whether laryngoscopy and tracheal intubation were easier when using the Pentax-AWS (Tokyo, Japan), a new videolaryngoscope, than when applying the Macintosh laryngoscope, during manual in-line neck stabilization.

METHODS

In 203 anaesthetized patients with manual in-line neck stabilization, we inserted the Pentax-AWS and a Macintosh laryngoscope, in turn, and recorded the view of the glottis and time taken to laryngoscopy. The success rate of tracheal intubation (within 120 s) and time to intubation were also recorded.

RESULTS

The view of the glottis was significantly better with the Pentax-AWS than with the Macintosh laryngoscope (P<0.001). For the Macintosh laryngoscope, the view was obscured in 22 of 203 patients (11%) (Grade 3 in 21 patients and Grade 4 in one patient), whereas for the Pentax-AWS, the glottis was always clearly seen (Grade 1). Time taken to see the glottis with the Pentax-AWS [mean (sd): 6.0 (3.1) s] was significantly shorter than with the Macintosh laryngoscope [11.0 (5.0) s] (95% CI for difference: 4-6 s). The success rate of tracheal intubation with the Pentax-AWS (all of 99 patients) was significantly higher than with the Macintosh laryngoscope (93 of 104 patients) (P=0.001). Time taken for intubation was similar between the Macintosh laryngoscope [51 (27) s] and the Pentax-AWS [54 (14) s] (95% CI for difference: -9 to 3 s).

CONCLUSIONS

In patients with stabilized neck, the Pentax-AWS provided a better view of the glottis and a higher success rate of tracheal intubation, compared with the conventional Macintosh laryngoscope.

273 REMOVAL OF ACROSOME FROM SPERM HEADS IMPROVES DEVELOPMENT OF RAT ZYGOTES THROUGH INTRACYTOPLASMIC SPERM INJECTION

In intracytoplasmic sperm injection (ICSI), sperm chromatin is introduced into the oocyte together with acrosome, which does not enter cytoplasm of oocytes during normal fertilization. In mice, acrosome of sperm head has a detrimental effect on embryonic development of the ICSI oocytes (Morozumi et al. 2006 Proc. Natl. Acad. Sci. USA 103, 17 661–17 666). We examined the effect of acrosome removal of frozen/thawed (F/T) rat sperm on development to term of the ICSI oocytes in order to improve production efficiency of live offspring from F/T rat spermatozoa through ICSI. In experiment 1, epididymal spermatozoa of the Wistar rats were frozen as described previously (Seita et al. 2005 Reprod. Fertil. Dev. 18, 256 abst). The F/T spermatozoa were sonicated to separate sperm heads. The sperm heads were divided into 3 treatment groups; nontreated sperm head (control), sperm heads exposed in 0.02% of Triton X-100 solution for 1 min (TX), sperm heads exposed in 0.02% lysolectin solution for 1 min (LL). Acrosomal status of the sperm heads was then examined by FITC-peanut agglutinin stain. In experiment 2, sperm heads of the control, TX, and LL treatments were microinjected into denuded oocytes obtained from superovulated females (Hirabayashi et al. 2002 Transgenic Res. 11, 221–228). The ICSI oocytes were cultured and observed for the formation of pronuclei (2PN) for 6 h and blastocyst formation at 120 h of culture. In experiment 3, the ICSI oocytes cultured for 6 h were transferred to recipient females to examine development to term. Statistical analyses of the results were carried out by 1-way ANOVA. In experiment 1, the TX (76%) and LL (89%) treatments showed higher rates of acrosome removal than that of the control (24%) group (P < 0.05). In experiment 2, the percentage of 2PN formation at 6 h after ICSI was not significantly different among sperm-treated groups, although the TX (76%) and LL (70%) groups were higher than the control (24%) group at 4 h (P < 0.05). The percentages of blastocyst formation were not significantly different among sperm-treated groups (control: 10%; TX: 25%; and LL: 25%). In experiment 3, the efficiency of development to term of the TX treatment group (21%: 12/57) was significantly higher than the control (5%: 3/55; P < 0.05), although the LL treatment group (16%: 12/75) was not significantly different from the control and TX treatment groups. These results indicate that acrosome removal using TX of F/T rat sperm heads before ICSI improves development to term of the ICSI oocytes. This benefical effect of acrosome removal may be due to the quick release of sperm-activating factors from sperm heads after ICSI in the rat.

313 IMPROVEMENT OF FERTILIZATION IN VITRO BY PRE-INCUBATION OF FROZEN - THAWED RAT SPERMATOZOA WITH CAFFEINE-SUPPLEMENTED MEDIUM

We previously reported the successful production of live offspring from cryopreserved rat spermatozoa through IVF (2006 Reprod. Fertil. Dev. 18, 256). The objective of the present study was to improve the IVF system with frozen–thawed spermatozoa for more efficient reproduction of live offspring. We examined the effect of caffeine-supplemented medium on post-thaw sperm fertility in vitro. Epididymal spermatozoa of Wistar rats were cryopreserved in 2.0 mL of freezing medium containing 23% (v/v) egg yolk, 8.0% (w/v) lactose monohydrate, and 0.7% (v/v) Equex STM. Post-thaw spermatozoa were diluted to 0.5 to 1.5 � 106 sperm mL-1 in a droplet of 200 �L of R1ECM as the pre-incubation medium. In Experiment 1, the effect of caffeine-supplemented medium on fertility in vitro was examined. The post-thaw spermatozoa were incubated for 5 h in pre-incubation medium with added caffeine at concentrations of 0, 1, 2, and 4 mM. Ovulated oocytes were introduced into droplets of the pre-incubation medium and co-cultured for 10 h. The oocytes were denuded and fixed to examine for 2 pronuclei formation (2PNF). In Experiment 2, the effect of caffeine-supplemented medium on post-thaw sperm function was examined using the chlortetracycline (CTC) fluorescence assessment. The post-thaw spermatozoa were incubated in pre-incubation medium with added caffeine at concentrations of 0 (Caf+) and 2 mM (Caf-), and CTC patterns were examined hourly until 6 h later. Statistical analyses of the results were carried out by one-way ANOVA. In Experiment 1, the percentages of 2PNF were 14 � 6, 32 � 8, 42 � 4, and 27 � 5% for the 0, 1, 2, and 4-mM groups, respectively, and only the 2-mM group was different from the 0-mM group (P &lt; 0.05). In Experiment 2, the rate of capacitated spermatozoa was not significantly different (P &gt; 0.05) among incubation times in the Caf+ group, but the rates at 5 and 6 h were lower (P &lt; 0.05) than the rate at 1 h in the Caf- group. Although the rates of acrosome-reacted spermatozoa were not significantly different (P &gt; 0.05) in the Caf+ group after 3 h of incubation, the accelerated trend of the acrosome reaction was observed in the Caf- group with increasing incubation time. The results demonstrated that frozen–thawed rat spermatozoa pre-incubated in medium containing 2 mM caffeine could improve in vitro fertility. This positive effect of caffeine would be provided to induce and keep sperm capacitation, and to inhibit the spontaneous sperm acrosome reaction in frozen–thawed rat spermatozoa.

Shedding of porcine circovirus into colostrum of sows

The purpose of the present study was to investigate porcine circovirus (PCV) shedding into the milk of sows. Colostrum was collected from 33 sows. PCV1 was isolated from four of 33 milk whey samples. PCV1 DNA was detected by polymerase chain reaction in three of these samples and in three of 10 milk cell samples. PCV2 was also isolated and detected from every single milk whey sample. These results showed that PCV1 and PCV2 were shed into the milk of sows and suggest that PCV can be transmitted to offspring by an oral route through milk.

Dynamics of capillary condensation in aerogels

Dynamics of capillary condensation of liquid 4He in various density silica aerogels was investigated systematically. Interfaces were clearly visible when bulk liquid was rapidly sucked into the aerogel. Time evolution of the interface positions was consistent with the Washburn model and their effective pore radii were obtained. Condensation was a single step in a dense aerogel and two steps in a low density aerogel. Crossover between the two types of condensation was observed in an intermediate density aerogel. Variety of the dynamics may be the manifestation of the fractal nature of aerogels which had a wide range of distribution of pore radii.

297 BIRTH OF LIVE RATS THROUGH IN VITRO FERTILIZATION USING CRYOPRESERVED SPERMATOZOA: SPERM FERTILITY IMPROVED BY FREEZING AT - 150°C

We previously reported that damages to spermatozoa by cold shock can be avoided by cooling slowly at 0.5�C/min to 5.0�C (Seita et al. 2005 Reprod. Fertil. Dev. 17, 277-278). The objective of the present study was to develop an in vitro fertilization (IVF) system with frozen-thawed rat spermatozoa for more efficient reproduction of live offspring. We examined the effect of freezing temperatures (cooling 5.0�C to pre-plunging) on post-thaw sperm motility, plasma membrane integrity, and fertility in vitro. Epididymal spermatozoa of Wistar rats were collected in 2.0 mL of freezing medium containing 23% (v/v) egg yolk, 8.0% (w/v) lactose monohydrate, and 0.7% (v/v) Equex STM (Nova Animal Sales, Inc., Scituate, MA, USA) at room temperature. Samples were loaded into 0.25-mL straws and cooled to 5.0�C at 0.5�C/min in a programmable freezer. Next, the samples were exposed to liquid nitrogen (LN) vapor at various freezing temperatures (-120�C, -150�C or -180�C) above the LN level for 15 min and then plunged into LN. Straws were thawed in a 37�C water bath for 10 min. The thawed samples were diluted to 0.5-1.5 � 106 sperm/mL in a droplet of 200 �L of R1ECM and then pre-incubated for 5 h. Ovulated oocytes were introduced into the droplet and co-cultured for 10 h. The oocytes were denuded, fixed, and/or examined for two pronuclei (2PN) formation microscopically. The denuded oocytes, which were fertilized with spermatozoa frozen at -150�C and were microscopically confirmed to have 2PN formation, were transferred to pseudo-pregnant recipient females. IVF was also performed by the same method using fresh spermatozoa as the control. Differences in the sperm motility and plasma membrane integrity were analyzed by ANOVA, and the IVF data were analyzed by chi-square test. At 2 h after thawing the motility of spermatozoa frozen at -150�C was significantly higher than that of spermatozoa frozen at -180�C (19.8% and 11.1%; P < 0.05), although the sperm plasma membrane integrity was not significantly different among different freezing temperatures, -120�C, -150�C, and -180�C (18.2%, 23.5%, and 17.9%; P > 0.05). The percentage of oocytes with 2PN was not significantly different between the -150�C frozen and the control (fresh spermatozoa) groups [59% (131/221) and 62% (155/251); P > 0.05], although that of frozen spermatozoa at -120�C and -180�C [20% (38/188) and 23% (35/153)] were significantly lower than that of frozen spermatozoa at -150�C (P < 0.05). A total of 168 putative fertilized zygotes with 2PN were transferred to eleven recipients, and 87 live young were born. In conclusion, our results indicated that post-thaw motility of cryopreserved rat spermatozoa was improved by using a suitable cooling protocol, and the IVF system used in the present study would effectively produce offspring from the cryopreserved epididymal rat spermatozoa. To our knowledge, this procedure is the first successful production of live offspring from cryopreserved rat spermatozoa through in vitro fertilization.