[The multisystem deformities features of Klippel-Feil syndrome patients combined with congenital scoliosis].

Objective: To summarize the characteristics of multisystem deformities in patients with Klippel-Feil syndrome (KFS) combined with congenital scoliosis (CS). Methods: Within the framework of the "Deciphering Disorders Involving Scoliosis and Comorbidities (DISCO)" research collaboration, a retrospective analysis was conducted on patients diagnosed with KFS and CS at Peking Union Medical College Hospital between April 2005 and August 2022. Patient data, including imaging examinations and medical records, were collected to summarize the spinal and associated deformities. Results: A total of 82 KFS patients with concurrent CS were included, comprising 42 males and 40 females. The average age was (12.8±8.9) years. Among the KFS patients, there were 31 cases of Type Ⅰ, 12 cases of Type Ⅱ, and 39 cases of Type Ⅲ. The most common location for the major curve of scoliosis was the mid-thoracic segment (42 cases, 51.2%). Hemivertebrae deformities were most frequently observed in the upper thoracic segment (31 cases, 60.8%). There were no statistically significant differences in age, gender, major curve Cobb angle, or region of hemivertebrae occurrence among the different types of KFS (all P>0.05). Apart from spinal vertebral deformities, intraspinal deformities had the highest comorbidity rate (33 cases, 40.2%). The subjects were divided into two groups based on the presence or absence of intraspinal deformity (absence as group G0, presence as group G1), there was a statistically significant difference in the main Cobb angle [M(Q1, Q3)] between the two groups, which was 45.0° (27.5°, 62.0°) and 60.0° (37.5°, 83.5°), respectively (P=0.044). Additionally, a portion of the patients had concurrent cardiovascular system abnormalities (13 cases, 15.9%), craniofacial-ocular-auricular abnormalities (8 cases, 9.8%), genitourinary system abnormalities (7 cases, 8.5%), and gastrointestinal abnormalities (2 cases, 2.4%). Conclusions: Patients with KFS combined with CS commonly present with a major curve of spinal deformity in the mid-thoracic segment and often have comorbidities involving multiple systems. When combined with intraspinal anomalies, the major curve exhibits a greater degree of curvature.

[Influencing factors of hypertension and diabetes care cascade: a qualitative study].

Objective: Employing the cascade care model, this qualitative study explores determinants influencing the cascading care stages of hypertension and diabetes by interviewing various stakeholders. Methods: In July 2023, purposive sampling was employed to recruit participants from Gongyi and Wugang cities in Henan Province, and Linqu County in Weifang City, Shandong Province. Semi-structured in-depth interviews were conducted with representatives of policymakers, healthcare institution managers, providers, and patients with hypertension and diabetes.And thematic analysis was performed using both inductive and deductive approaches. Results: A total of 82 individuals were interviewed, with an age range of (53.8±12.0) years, among which 48 (58.5%) were male; including 5 policymakers, 10 institutional managers, 20 healthcare providers, and 47 patients with hypertension and diabetes. The study identified both barriers and facilitating factors at the patient, healthcare provider, and system levels across various stages: awareness, screening, diagnosis, treatment, long-term management, and control of hypertension and diabetes. Conclusion: By delineating and analyzing the barriers and facilitators at each stage of hypertension and diabetes care, this study lays the groundwork for the development of effective, feasible, and sustainable implementation pathways, with significant implications for the enhanced management of hypertension and diabetes in China.

[Integrated management and prognosis analysis of fetus with complete transposition of the great arteries during pregnancy and perinatal period].

Objective: To investigate the prenatal diagnosis, integrated management and prognosis of fetal complete transposition of the great arteries (D-TGA) detected by ultrasonography. Methods: The prenatal diagnosis, integrated management and prognosis of 19 D-TGA fetuses found by ultrasound during pregnancy in Peking University People's Hospital from January 2014 to June 2019 were analyzed retrospectively. Results: The incidence of D-TGA was 0.12% (19/16 028) among fetuses diagnosed by ultrasound during 5 years. Among the 19 cases, there were 7 cases (7/19) of D-TGA alone, 7 cases (7/19) of D-TGA combined with ventricular septal defect (VSD), 5 cases (5/19) of D-TGA combined with other cardiac malformations; 2 cases (2/19) of D-TGA combined with extra cardiac malformations, and 1 case (1/19) of fetal growth restriction. Nuchal translucency (NT) thickening was found in 3 cases (3/19) at the first trimester of pregnancy. Among the 19 D-TGA fetuses found by ultrasound examination, 18 (18/19) had chromosome karyotype analysis of fetuses or newborns, and chromosomal abnormalities were found in 2 cases, all of which were terminated in the second trimester of pregnancy. The integrated management and multidisciplinary diagnosis and treatment of D-TGA fetuses during pregnancy and perinatal period were carried out. Nine cases (9/19) had induction in the second trimester of pregnancy, 10 cases (10/19) were delivered at term, and the gestational week of delivery was (38.3±0.7) weeks, among which 6 cases (6/10) were delivered by caesarean section due to obstetric factors, and 4 cases (4/10) were delivered by vaginal birth. The oxygen saturation was (69.2±11.3)% at birth and (77.8±6.7)% when transferred to the department of pediatrics. Except for one case lost to follow-up, the other 9 newborns received operation. The average operation time was (21.8±22.1) days after birth, 8 cases (8/9) completed one operation and 1 case (1/9) performed two operations. All of the 9 cases treated by surgery were followed up well. Conclusions: Prenatal diagnosis, individualized evaluation and integrated management during pregnancy and perinatal period should be carried out for the patients with fetal D-TGA detected by ultrasound. Fetal D-TGA is not an indication of cesarean section. The open of ductus arteriosus can be maintained with drugs when necessary after birth, and a good prognosis could be obtained through surgery.

The correlation between CT findings of diffuse axonal injury and the expression of neuronal aquaporin in patients with craniocerebral injury.

OBJECTIVE: The paper aimed at exploring the correlation between CT findings of diffuse axonal injury and the expression of neuronal aquaporin in patients with craniocerebral injury. PATIENTS AND METHODS: 150 patients with diffuse axonal injury diagnosed by CT and 50 healthy physical examinators were selected as the study objects. According to the craniocerebral CT and GCS scale scores, the patients were divided into DAI light group, medium group, and heavy group. The general conditions of patients were observed and recorded, and the brain pathological morphology, craniocerebral edema and CT imaging results of the patients in each group were compared. Changes in serum and brain AQP-4 levels were detected by RT-PCR and Western blot, and the correlation between CT manifestations of DAI and the expression of neuronal aquaporin was investigated. RESULTS: The results of DAI's pathological morphology, cerebral edema and CT imaging showed that the brain tissue of each group of DAI had a certain degree of injury. With the increase of the injury degree, the degree of edema and the number of axonal injuries sharply increased, and the difference was significant (p-value < 0.05). Therefore, CT could be used as an effective basis for the rapid and efficient diagnosis of DAI. RT-PCR, Western blot and Spearman correlation analysis showed that the levels of AQP-4 in the serum and brain tissue of DAI patients were significantly increased. With the increase of the degree of diffuse axonal injury, the expression level of AQP-4 was further increased, and the difference was significant (p-value < 0. 05). The CT manifestations of patients in each group were positively correlated with the expression level of AQP-4 protein. CONCLUSIONS: AQP-4 can be used as an important molecular index to judge the condition and prognosis of DAI, providing a new non-invasive detection method for the clinical diagnosis and treatment of DAI, which has high clinical application value.

[Prevalence of osteoporosis and related factors in postmenopausal women aged 40 and above in China].

Objective: To understand the prevalence of osteoporosis and related factors in postmenopausal women aged ≥40 years in China and provide scientific evidence for osteoporosis prevention and control. Methods: Data of this study were from the 2018 China Osteoporosis Epidemiological Survey, covering 44 counties (districts) in 11 provinces in China. Related variables were collected by questionnaire survey and physical measurement, and the BMD of lumbar spine and proximal femur was measured by dual-energy X-ray absorption method. The prevalence of osteoporosis and its 95%CI in postmenopausal women aged ≥40 years were estimated with complex sampling weights. Results: A total of 5 728 postmenopausal women aged ≥40 years were included in the analysis and the prevalence of osteoporosis was 32.5% (95%CI: 30.3%-34.7%). The prevalence of osteoporosis in postmenopausal women aged 40-49 years, 50-59 years, 60-69 years, 70-79 years, and ≥80 years were 16.0% (95%CI:4.5%-27.5%), 18.4% (95%CI:15.9%-20.8%), 37.5% (95%CI:34.5%-40.4%), 52.9% (95%CI: 47.5%-58.3%), and 68.0% (95%CI:55.9%-80.1%) respectively. The prevalence of osteoporosis was higher (P<0.001) in those with education level of primary school or below (47.2%, 95%CI: 43.0%-51.3%) and in those with individual annual income less than 10 000 Yuan, (40.3%, 95%CI: 36.9%-43.7%). The prevalence of osteoporosis was 35.1% in rural areas (95%CI: 32.0%-38.1%), which was higher than that in urban areas (P<0.001). The prevalence of osteoporosis in low weight, normal weight, overweight and obese groups were 69.9% (95%CI: 59.0%-80.8%), 42.2% (95%CI: 38.7%-45.7%), 24.2% (95%CI: 21.3%-27.1%) and 14.6% (95%CI: 11.1%-18.0%), respectively. The prevalence of osteoporosis in those with menstrual maintenance years ≤30 years and in those with menopause years ≥11 years were 46.1% (95%CI:40.8%-51.3%) and 48.2% (95%CI:45.0%-51.3%), respectively. Multivariate logistic analysis showed that age ≥60 years, education level of primary school or below, annual household income per capita less than 10 000 Yuan, low body weight, menstrual maintenance years ≤30 years, menopause years ≥11 years were risk factors of osteoporosis in postmenopausal women in China. Conclusions: The prevalence of osteoporosis was high in postmenopausal women aged ≥40 years in China, and there were differences in osteoporosis prevalence among different socioeconomic groups. Effective interventions should be taken for the prevention and control of osteoporosis in key groups in the future.

Skeletal muscle-secreted myokine interleukin-6 induces white adipose tissue conversion into beige adipose tissue in myostatin gene knockout pigs.

Myostatin (MSTN) is primarily expressed in skeletal muscle and plays an important role in the regulation of muscle growth and development as well as fat deposition; however, little is known about the molecular mechanism through which MSTN regulates body fat deposition. Therefore, in this study, we sought to identify the signaling pathways through which MSTN regulates fat accumulation in pigs. MSTN knockout (MSTN-/-) pigs showed increased muscle mass, decreased fat mass, and a leaner body composition. In this study, we found that the adipose tissue of MSTN-/- pigs exhibits the characteristics of beige adipose tissue, and the mRNA expression levels of beige adipose marker genes, including UCP3, Cidea, and CD137, were significantly increased. Remarkably, the observed beige phenotype was not adipocyte autonomous but rather caused by muscle-secreted myokine interleukin (IL)-6. This occurrence results in increased AMP-activated protein kinase (AMPK) phosphorylation in adipose tissue, which subsequently activates peroxisome proliferator-activated receptor gamma coactivator 1α and the conversion of white adipocytes to beige in pigs. Therefore, we concluded that MSTN deficiency leads to increased IL-6 secretion in skeletal muscle and activates AMPK in adipocytes, thereby increasing the beige adipose tissue in MSTN-/- pigs.

Germinal vesicle chromatin configuration and meiotic competence is related to the oocyte source in canine.

This study investigated the effect of deriving oocytes from different stages of the estrous cycle on oocyte diameter, germinal vesicle (GV) chromatin configuration, and in vitro meiotic competence in canine oocytes. Cumulus oocyte complexes (COCs) were recovered from both ovaries during anestrous, follicular, and luteal phases and in vivo ovulated oocytes. The diameter of canine oocyte was compared with or without the zona pellucida (ZP) before in vitro maturation (IVM). Also, GV chromatin configuration was evaluated before (0 h) or 72 h after IVM by fixation with 3.7% formaldehyde supplemented with 10 microg/ml Hoechst 33342 for 30 min. COCs were matured in TCM199 supplemented with 10% fetal bovine serum (FBS), 0.6 mM cysteine, 0.2 mM pyruvic acid, 50 microg/ml gentamycin sulfate, and 20 microg/ml 17beta-estradiol (E(2)) at 39 degrees C and 5% CO(2) in air for 72 h. The diameter of in vivo ovulated oocytes with the ZP (167.5+/-12.7 microm) or without ZP (133.9+/-5.3 microm) was significantly greater (p<0.05) than those of anestrous, follicular, and luteal oocytes (with ZP, 151.2+/-7.4, 153.1+/-8.8 and 152.8+/-5.4 microm, respectively; without ZP, 115.3+/-7.6, 122.1+/-4.9 and 114.3+/-6.6 microm, respectively). At 0 h, the GV-II configuration was more prevalent in oocytes from anestrual ovaries than from follicular or luteal ovaries or in vivo ovulated oocytes (63.6% versus 14.8%, 33.0%, and 0.0%; p<0.05), whereas the proportion of oocytes with the GV-V configuration was higher in follicular phase and ovulated oocytes than in oocytes from anestrus and luteal phase (57.4% and 100% versus 2.0% and 22.7%; p<0.05). However, oocytes in luteal phase exhibited diverse GV configurations (10.3%, 33.0%, 16.5%, 13.4%, and 22.7% in GV-I, GV-II, GV-III, GV-IV, and GV-V, respectively). After 72 h post-IVM, a greater percentage of in vivo ovulated oocytes progressed to MII than those oocytes collected during anestrous, follicular, and luteal phases (50.0% versus 5.5%, 11.5%, and 9.1%; p<0.05). In conclusion, the oocyte diameter, GV chromatin configuration, and meiotic maturation of canine COCs are related to the oocyte source. These results indicated that the oocyte source could be critical to nuclear progression to MII stage in canines.

Production of second-generation cloned cats by somatic cell nuclear transfer.

We successfully produced second-generation cloned cats by somatic cell nuclear transfer (SCNT) using skin cells from a cloned cat. Skin cells from an odd-eyed, all-white male cat (G0 donor cat) were used to generate a cloned cat (G1 cloned cat). At 6 months of age, skin cells from the G1 cloned cat were used for SCNT to produce second-generation cloned cats. We compared the in vitro and in vivo development of SCNT embryos that were derived from the G0 donor and G1 cloned donor cat's skin fibroblasts. The nuclei from the G0 donor and G1 cloned donor cat's skin fibroblasts fused with enucleated oocytes with equal rates of fusion (60.7% vs. 58.8%, respectively) and cleavage (66.3% vs. 63.4%). The 2-4-cell SCNT embryos were then transferred into recipients. One of the five recipients of G0 donor derived NT embryos (20%) delivered one live male cloned kitten, whereas 4 of 15 recipients of the G1 cloned donor cat derived NT embryos (26%) delivered a total of seven male second-generation cloned kittens (four live kittens from one surrogate, plus two stillborn kittens, and one live kitten that died 2d after birth from three other surrogate mothers). The four second-generation cloned kittens from the same surrogate all had a white coat color; three of the four second-generation cloned kittens had two blue eyes, and one of the second-generation cloned kittens had an odd-eye color. Despite low cloning efficiency, cloned cats can be used as donor cats to produce second-generation cloned cats.

Histone deacetylase inhibitor M344 significantly improves nuclear reprogramming, blastocyst quality, and in vitro developmental capacity of cloned pig embryos.

M344 is a novel histone deacetylase inhibitor. There is no report on the effect of M344 treatment on the development of pig embryos after somatic cell nuclear transfer (SCNT). In the present study, we investigated the effect of M344 on the blastocyst formation rate in cloned embryos, acetylation level of histone H4 lysine 12 (AcH4K12), and the expression of pluripotency-related genes , , and . Our results indicated that treatment with 5 µ M344 for 6 h improved the development of porcine embryos, in comparison with the untreated group (25.1% ± 5.0 vs. 10.9% ± 2.4; < 0.05). Moreover, M344-treated embryos had increased average fluorescence intensity of AcH4K12 at the pseudo-pronuclear stage ( < 0.05). However, no differences exist in Oct4, NANOG, and SOX2 expression in M344-treated and untreated SCNT blastocysts. In evaluating the effect of M344 on in vivo development, 845 M344-treated embryos were transferred into 3 surrogates, 1 of whom became pregnant and developed 3 fetuses. These findings suggested that M344 elevated the level of histone acetylation, facilitated the nuclear programming, and subsequently improved the developmental competence of pig SCNT embryos.

Tunable fly's-eye lens made of patterned polymer-dispersed liquid crystal.

A fly's-eye lens was fabricated using polymer-dispersed liquid crystals and its optical properties were evaluated. The morphologies were examined under an optical microscope. The forming process has been simulated based on a patterned photo-polymerization technique in which the spatially modulated reaction rate has been coupled with the time-dependent Ginzburg-Landau (TDGL) equations with the free energies relating to isotropic mixing, nematic ordering, and network elasticity incorporated. The simulated results are in good agreement with the experimental results. The beam profile was tested using a CCD. The results showed that this fly's-eye lens could modulate a Gaussian beam into a mesa-like beam. Such device is potentially useful in beam shaping and many illumination systems that require uniform beam profile.

Nuclear and microtubule remodeling and in vitro development of nuclear transferred cat oocytes with skin fibroblasts of the domestic cat (Felis silvestris catus) and leopard cat (Prionailurus bengalensis).

The leopard cat (Prionailurus bengalensis), a member of the felidae family, is a threatened animal in South Korea. In terms of protecting endangered felids, nuclear transfer (NT) is a potentially valuable technique for assuring the continuation of species with dwindling numbers. In the present experiment, nuclear and microtubule remodeling and the in vitro developmental potential of enucleated domestic cat oocytes reconstructed with nuclei of somatic cells from either domestic cat fibroblast (DCF) or leopard cat fibroblast (LCF) were evaluated. Microtubule aster is allocated to de-condensed chromatin following nuclear transfer (3h after activation) of fibroblast cells from both domestic and leopard cats, suggesting the introduction of a somatic cell centrosome. The transferred fibroblast nuclei formed a large, swollen, pronuclear-like structure in most reconstructed oocytes, in the cat or leopard cat. At 18h following nuclear transfer, mitosis occurred, and according to the photo (F) it appears that spindle microtubules and two asters were observed. The percentages of blastocyst formation from nuclear transfer embryos derived from domestic cat fibroblasts (4/46, 8.6%) were not significantly different than those for nuclear transfer embryos constructed with leopard cat fibroblasts (4/52, 7.6%). These results indicate that nuclear and microtubule remodeling processes and in vitro developmental ability are similar in reconstructed cat oocytes following transfer of nuclei from either domestic or leopard cats.

Sensitivity of canine oocytes to low temperature.

This study compared the viability of canine oocytes after storage for 5 h at 4 or 38 degrees C. The ovaries were collected after ovariohysterectomy of bitches and transported to the laboratory within 5 h at 4 or 38 degrees C. The collected oocytes were matured in DMEM supplemented with 10% FBS, 0.6 mM/mL cysteine, 0.2 mM pyruvic acid, 20 ng/mL E2 and 1 microg/mL rbST, and incubated for 0, 24 and 48 h, at 38 degrees C and in 95% air with 5% CO2. The viability of the oocytes after 0 h did not differ significantly between 4 and 38 degrees C group (79.6% versus 83.9%), but after 24 and 48 h, significant differences were apparent (13.2% versus 77.8% after 24 h and 0.0% versus 72.9% after 48 h; P < 0.05). Therefore, canine oocytes were remarkably sensitive to low temperatures.

Dynamic switching of optical vortices with dynamic gamma-correction liquid crystal spiral phase plate.

Generation and dynamic switching of optical vortices from charge 1 up to charge 6 at wavelength of 0.6328-microm by one dynamic gamma-correction liquid crystal spiral phase plate are reported. The liquid crystal spiral phase plate comprises 46 slices, which are driven by a 16- channel voltage output card. The spiral phase plate was designed based on the relationship between the topological charge purity of an optical vortex generated by the spiral phase plate and the total number of slices. The calculation results show that a minimum slice number of 44 is required for generating optical vortices up to charge 6 with charge purity above 94%.

The histone deacetylase SIRT6 inhibits ovarian cancer cell proliferation via down-regulation of Notch 3 expression.

OBJECTIVE: SIRT6 belongs to the NAD+-dependent class III deacetylase sirtuin family. Accumulating evidences have supported the critical role of SIRT6 in the proliferation, differentiation, cell cycle progression and apoptosis of cancer cells. The present study aims to determine the expression of SIRT6 in human ovarian cancer tissues and further investigate its the biological effect in ovarian cancer. MATERIALS AND METHODS: Real time PCR and western blot were performed to examine the mRNA and protein levels SIRT6 in human ovarian cancer tissues and normal tissues. The proliferation of ovarian cancer cells was determined using MTT methods. Small interfering RNA (siRNA) technology was used to down-regulate the expression of SIRT6 and Notch 3. RESULTS: We found that the SIRT6 expression was significantly reduced in human ovarian cancer tissues compared to the normal tissues. Furthermore, our data showed that overexpression of SIRT6 inhibited the proliferation of ovarian cancer cells SKOV3 and OVCAR3. By contrast, down-regulation of SIRT6 enhanced ovarian cancer cells growth. In addition, our study showed that SIRT6 suppressed the expression of Notch 3 both at the mRNA and protein levels in ovarian cancer cells. CONCLUSIONS: Our findings indicated that SIRT6 inhibited the proliferation of ovarian cancer cells through down-regulation of Notch 3 expression, and might provide novel therapeutic targets for ovarian cancer therapy.

A study on the mutagenicity of 102 raw pharmaceuticals used in Chinese traditional medicine.

The mutagenic potential of traditional Chinese drugs was studied. After extraction with boiling water and frozen vacuum drying, preparations from 102 raw drugs were tested with the Ames test, and the micronucleus and chromosomal aberration assays in mice in vivo. Astragalus mongholicus Bunge (+S9), Sophora japonica L. (+/- S9) and Eucommia ulmoides Oliv. (+/- S9) were found to significantly induce His+ revertants in Salmonella typhimurium TA98 and/or TA100. Besides these 3, 10 other extracts were positive in the chromosomal aberration and micronucleus assays in mice. They are Datura metal L., Artemisia capillaris Thunb., Carthamus tinctorius L., Forsythia suspensa Thumb., Rehmannia glutinosa f. Hueichingensis (fermented), Paeonia suffruticosa Andr., Platycodon grandiflorum Jacq. DC., Cinnamomum mairei Levl., Notopterygium incisium Ting., and Sophora flavescens Ait. The relevance of these findings is discussed.

Effects of paving asphalt fume exposure on genotoxic and mutagenic activities in the rat lung.

Asphalt fumes are complex mixtures of aerosols and vapors containing various organic compounds, including polycyclic aromatic hydrocarbons (PAHs). Previously, we have demonstrated that inhalation exposure of rats to asphalt fumes resulted in dose-dependent induction of CYP1A1 with concomitant down-regulation of CYP2B1 and increased phase II enzyme quinone reductase activity in the rat lung. In the present study, the potential genotoxic effects of asphalt fume exposure due to altered lung microsomal enzymes were studied. Rats were exposed to air or asphalt fume generated under road paving conditions at various concentrations and sacrificed the next day. Alveolar macrophages (AM) were obtained by bronchoalveolar lavage and examined for DNA damage using the comet assay. To evaluate the systemic genotoxic effect of asphalt fume, micronuclei formation in bone marrow polychromatic erythrocytes (PCEs) was monitored. Lung S9 from various exposure groups was isolated from tissue homogenates and characterized for metabolic activity in activating 2-aminoanthracene (2-AA) and benzo[a]pyrene (BaP) mutagenicity using the Ames test with Salmonella typhimurium YG1024 and YG1029. This study showed that the paving asphalt fumes significantly induced DNA damage in AM, as revealed by DNA migration in the comet assay, in a dose-dependent manner, whereas the micronuclei formation in bone marrow PCEs was not detected even at a very high exposure level (1733 mg h/m3). The conversion of 2-AA to mutagens in the Ames test required lung S9-mediated metabolic activation in a dose-dependent manner. In comparison to the controls, lung S9 from rats exposed to asphalt fume at a total exposure level of 479+/-33 mg h/m3 did not significantly enhance 2-AA mutagenicity with either S. typhimurium YG1024 or YG1029. At a higher total asphalt fume exposure level (1150+/-63 mg h/m3), S9 significantly increased the mutagenicity of 2-AA as compared to the control. However, S9 from asphalt fume-exposed rats did not significantly activate the mutagenicity of BaP in the Ames test. These results show that asphalt fume exposure, which significantly altered both phases I and II metabolic enzymes in lung microsomes, is genotoxic to AM and enhances the metabolic activation of certain mutagens through altered S9 content.

Development of rabbit parthenogenetic oocytes and nuclear-transferred oocytes receiving cultured cumulus cells.

The present study determined a suitable parthenogenetic activation procedure for rabbit oocytes and examined the developmental potential of enucleated oocytes receiving cultured cumulus cells. Unfertilized oocytes recovered from superovulated rabbits were activated with one or two sets of electrical pulses, with or without subsequent administration of 6-dimethylaminopurine (6-DMAP). The proportion of oocytes treated with one or two sets of electrical pulses and 6-DMAP that cleaved (87% and 98%, respectively) and developed into blastocysts (77% and 85%, respectively) was significantly higher (P < 0.05) than those activated with electrical pulses alone (30% and 42% for cleavage, 7% and 17% for blastocysts). Cumulus cells separated from ovulated oocytes obtained from mature rabbits were cultured for three to five passages and then induced to quiescence by serum starvation before nuclear transfer. The enucleated oocytes receiving cumulus cells were activated with electrical pulses followed by the addition of 6-DMAP, and cultured in vitro for 5 to 6 d or transferred to pseudopregnant recipient females 1 d after activation. Of 186 nuclear-transferred oocytes, 123 (66%) cleaved and 42 (23%) developed into blastocysts. After transfer of 174 nuclear-transferred oocytes to 8 recipient females, a total of 3 implantation sites were observed in 3 recipient females but no fetuses were obtained.

Mutagenicity and induction of drug-metabolizing enzyme activity by LPG combustion particulates in rats.

Methylene chloride extracts of particulates from liquefied petroleum gas (LPG) combustion appliance were studied by using Ames test, micronucleus test and inducibility of pulmonary and hepatic aryl hydrocarbon hydroxylase (AHH) and glutathione S-transferase (GST) in rats. The extracts showed mutagenicity for Salmonella typhimurium strain TA98 and its derivatives TA98NR and TA98/1,8-DNP6 with or without S9 mix. The revertants in strains TA98NR and TA98/1,8-DNP6 were less than 40% and 50% of that in strain TA98 without S9 mix, respectively. Positive results were obtained in mouse bone marrow micronucleus assay. Intratracheal instillation of the extracts led to increase in pulmonary (but not hepatic) AHH and GST activities in rats. It was seen that AHH was more sensitive than GST to induction by the extracts.

Mutagenicity of urine from individuals exposed to LPG combustion products.

The mutagenicity of urine from individuals exposed to the combustion products of liquefied petroleum gas (LPG) was detected with Salmonella typhimurium TA98 and its newly developed derivatives YG1021 (nitroreductase overproducing) and YG1024 (O-acetyltransferase overproducing). The detection showed significantly increased mutagenicity for the two YG strains and increased positive rates for all three strains in the presence of both rat liver S9 and beta-glucuronidase. Further analysis demonstrated that urine samples taken from smoking and non-smoking exposed individuals exhibited significantly higher mutagenic potency (revertants/10 microliters urine concentrate) than their corresponding controls. These results indicate that the increased urine mutagenicity is caused by the exposure to LPG combustion products or smoking. The mutagenic potency of urine samples of all exposed individuals tested with YG1024 was found to be about 7 times higher than with TA98. The difference in mutagenic potency was smaller for the same samples when comparison was made between YG1021 and TA98. This suggests that the mutagenic compounds present in the urine samples contain mainly aromatic compounds as glucuronide conjugates. Our results demonstrate that YG1024 is more sensitive than TA98 in detecting the mutagenicity of these samples. In addition, no significant difference in the mutagenic potency between the 'pure' exposed (non-smokers') and the 'pure' smokers' (unexposed) samples was found in all three tester strains. This might mean that the exposure extent of mutagens/carcinogens in LPG combustion products for exposed individuals roughly corresponds to the smoking level of smokers who smoke 20-40 cigarettes per day. Furthermore, the results also suggest that synergism might exist in the mutagenic effects of exposure to LPG combustion products and cigarette smoking.

Newly developed initial-flow cell filtrometer and the comparison with viscometry and ektacytometry on erythrocyte deformability.

According to Hanss's initial-flow rate method, F. Liao designed a new cell filtrometer in the early 1990s. The parameters, cell initial transit time (Tc) and membrane clogging rate (CR), can be determined by a single measurement with timing accuracy of 1 ms. The new cell filtrometer has two valuable features: a button-pushing operation to control electromagnetic valves; and an autocirculation of fluid in the cell filtrometer resulting in the same volume of leading fluid. A series of comparisons of the new filtrometry with viscometry or ektacytometry shows that the instrument seems to be more sensitive in detecting subpopulations of glutaraldehyde-hardened cells and the shift of deformability for all the cells. The reproducibility of the filtrometer for different membranes made in China and the USA is reasonable (CV < 5% for Tc). Preliminary application of the filtrometer indicates that it might be useful for trial study and routine clinical application.