A study of application effects of next-generation sequencing based preimplantation genetic testing for aneuploidies in advanced maternal age women

OBJECTIVE

To investigate if next-generation sequencing-based preimplantation genetic testing for aneuploidies could improve pregnancy outcomes in women of advanced maternal age.

MATERIALS AND METHODS

A retrospective analysis. The clinical data of 1099 couples treated in the First Medical Center of the Chinese PLA General Hospital from January 2019 to December 2021 were analyzed. They were divided into two groups based on whether they underwent a Next-generation sequencing-based preimplantation genetic test for aneuploidies. We analyzed and compared the biochemical pregnancy rate, clinical pregnancy rate, abortion rate, and live birth rate between the two groups.

RESULTS

The Preimplantation genetic testing for aneuploidies (PGT-A) group was associated with higher rate of biochemical pregnancy and clinical pregnancy than the non-PGT-A group, which were 63.9% vs. 56.4% (P = 0.009) and 54.4% vs. 45.6% (P < 0.001), respectively. The abortion rate was significantly lower in the PGT-A group compared to the non-PGT-A group (2.3% vs. 14.7%, P < 0.001). In addition, the live birth rate was significantly higher in the PGT-A group compared to the non-PGT-A group (52.1% and 30.9%, respectively, P < 0.001).

CONCLUSION

Next-generation sequencing-based preimplantation genetic testing for aneuploidies significantly improved the pregnancy outcomes in women of advanced maternal age.

Integrating EM and Patch-seq data: Synaptic connectivity and target specificity of predicted Sst transcriptomic types

Neural circuit function is shaped both by the cell types that comprise the circuit and the connections between those cell types ¹ . Neural cell types have previously been defined by morphology ^{2, 3} , electrophysiology ^{4, 5} , transcriptomic expression ^6-8 , connectivity ^9-13 , or even a combination of such modalities ^14-16 . More recently, the Patch-seq technique has enabled the characterization of morphology (M), electrophysiology (E), and transcriptomic (T) properties from individual cells ^17-20 . Using this technique, these properties were integrated to define 28, inhibitory multimodal, MET-types in mouse primary visual cortex ²¹ . It is unknown how these MET-types connect within the broader cortical circuitry however. Here we show that we can predict the MET-type identity of inhibitory cells within a large-scale electron microscopy (EM) dataset and these MET-types have distinct ultrastructural features and synapse connectivity patterns. We found that EM Martinotti cells, a well defined morphological cell type ^{22, 23} known to be Somatostatin positive (Sst+) ^{24, 25} , were successfully predicted to belong to Sst+ MET-types. Each identified MET-type had distinct axon myelination patterns and synapsed onto specific excitatory targets. Our results demonstrate that morphological features can be used to link cell type identities across imaging modalities, which enables further comparison of connectivity in relation to transcriptomic or electrophysiological properties. Furthermore, our results show that MET-types have distinct connectivity patterns, supporting the use of MET-types and connectivity to meaningfully define cell types.

Clinical Characteristics and Influence Factor Analysis of ABO Typing Discrepancy Among Patients in a Tertiary Hospital

BACKGROUND

An accurate interpretation of the ABO blood group of an individual is of utmost importance to ensure patient safety and good transfusion practices. The aim of the study was to determine the incidence and causes of ABO typing discrepancies among patients and analysis of the clinical characteristics as well.

METHODS

A retrospective observational study was carried out in the Department of Laboratory Medicine in the General Hospital of Chinese PLA from March 2018 to December 2020. Records of patients were collected and analyzed for frequency, clinical characteristics, and influencing factors of ABO typing discrepancies.

RESULTS

There were 132 ABO typing discrepancies patients (57 females, 75 males), aged from 3 to 84 (50.3 ± 19.3) years, with history of operation 89 cases (67.42%) and blood transfusion 23 cases (17.42%). In the control group, there were 142 cases (63 females and 79 males), aged 10 - 78 years (50.5 ± 15.55), with operation history 68 cases (47.88%) and blood transfusion history 2 cases (1.40%). Among the inconsistent blood types group, there were 59 cases (44.7%) type B, 38 cases (28.8%) type A, 28 cases (21.2%) type AB, and 7 cases (5.3%) type O. There were 21 cases (15.9%) in the department of hematology, 15 cases (11.36%) in the department of orthopedics, 14 cases (10.6%) in the department of hepatobiliary surgery, 11 cases (8.33%) in the department of general surgery, 11 cases (8.33%) in the department of vascular surgery, and less than 5% in other departments. The common cause of ABO typing discrepancies was due to low/weak affinity antibody (3.79%), low/weak affinity antibody B (18.18%), weak A antigen (3.03%), weak B antigen (12.12%), hematopoietic stem cell transplantation (10.60%), irregular antibody (46.70%), subtype (3.79%), and cold agglutination (1.51%). The diseases in the ABO discrepancy group mainly included hematological disorders, malignant tumors, osteoarthritis and so on. Binary logistic regression showed that hematological disorders, malignant tumors, history of operation (p = 0.01), and history of blood transfusion (p = 0.017) were the influencing factors of ABO typing discrepancies.

CONCLUSIONS

It is possible that the antibody of ABO blood group system could not be detected. The independent influence factors were hematological disorders, malignant tumor, blood transfusion history and operation history for ABO typing discrepancies. It was necessary to analyze the causes correctly and judge the correct blood group by serological methods.

Plasma miR-146a and miR-365 expression and inflammatory factors in patients with osteoarthritis

OBJECTIVE

To investigate the expression levels of micro-ribonucleic acid (miR)-146a and miR-365 in the plasma of osteoarthritis (OA) patients, to study their expression with the inflammatory factors and the severity of disease in patients and to analyse their diagnostic significance.

MATERIALS AND METHODS

A total of 42 OA patients diagnosed with OA and treated in our hospital from January 2017 to January 2018 were selected as the subjects, and 28 healthy people were enrolled as controls. The expressions of interleukin-1 beta (IL-1β) and IL-6 in the plasma of OA patients were detected via immunohistochemical staining. Moreover, the knee joint function of OA patients was evaluated by Lysholm score, Western Ontario and McMaster Universities (WOMAC) score and Visual Analogue Scale (VAS) score. The expression levels of plasma miR-146a and miR-365 in OA patients were measured through RT-PCR. Besides, the significance of the expression levels of miR-146a and miR-365 for the diagnosis of OA was analysed by ROC curves.

RESULTS

As compared with healthy people, OA patients had elevated expression levels of plasma IL-1β and IL-6, decreased Lysholm score, increased WOMAC and VAS scores as well as significantly up-regulated levels of plasma miR-146a and miR-365, which were of important significance for diagnosis.

CONCLUSION

The expression levels of plasma miR-146a, miR-365 and inflammatory factors are notably higher, the disease is more severe, and the function of knee joint movement is weaker in OA patients than those in healthy controls. It can be concluded that the levels of both miR-146a and miR-365 can serve as biomarkers of OA diagnosis.

SUN-021 Age-Specific Multiples of the Median Level of Serum Anti-Mullerian Hormone Is a Potential Marker for Diagnosis of Polycystic Ovary Syndrome

Serum anti-Mullerian hormone (AMH) levels are significantly higher in women with polycystic ovary syndrome (PCOS) than in normal ovulatory women. Different diagnostic cut-off values of AMH for discriminating women with PCOS from normal controls have been proposed. This is attributed partly to the different assay methods used with different calibration, as well as the age-related changes in serum AMH levels. We propose that it may be more appropriate to use age-specific multiples of the median (MoM) of AMH value instead of a “one for all ages” cut-off as a diagnostic threshold. Hence, we conducted a retrospective study to validate the performance of age-specific MoM of AMH value in the diagnosis of PCOS. We studied on a cohort of 751 women presented to the clinic for menstrual disorders or fertility treatment, including 473 women diagnosed with polycystic ovary syndrome by the Rotterdam criteria and 278 normal ovulatory controls. Their archived serum samples, collected at the early follicular phase, were retrieved and assayed for AMH by the automated Access AMH assay. The MOM AMH of each subject was calculated based on the age-specific reference ranges recently established by our group. Our results showed that MOM AMH was significantly higher in women with PCOS compared to controls (p<0.0001). When stratified into five-yearly age groups, there was no significant difference in MOM AMH (p>0.05) among women with PCOS aged 21-25, 26-30 and 31-35 years, but those aged 36-40 years had significantly higher MOM AMH (p<0.05) compared to the other younger age groups. Among the ovulatory controls, no significant difference was observed in MOM AMH among all the age groups (p>0.05). The area under the receiver-operator characteristic curve was 0.852 (95% CI 0.825-0.877) (p<0.0001) for discriminating women with PCOS from ovulatory controls by MOM AMH. The best cut-off value of MOM AMH was 1.44, and the corresponding sensitivity and specificity were 76% and 79% respectively. At the fixed specificity of 80% and the corresponding sensitivity of 73% (with positive and negative likelihood ratios of 3.8 and 0.33 respectively), the cut-off value of MOM AMH was 1.5. In conclusion, age-specific MOM AMH is a promising surrogate of antral follicle count in the diagnosis of PCOS.

Age-specific reference ranges of serum anti-müllerian hormone in healthy women and its application in diagnosis of polycystic ovary syndrome: a population study

OBJECTIVE

To establish the age-specific centiles of serum anti-müllerian hormone (AMH) levels in Chinese women, and to explore the use of multiples of median (MoM) AMH levels for the diagnosis of polycystic ovary syndrome (PCOS).

DESIGN

An observational study.

SETTING

University-affiliated hospitals and community clinics.

POPULATION

We included 3137 healthy women aged 20-44 years recruited prospectively or who had archived serum samples from previous research projects. Another validation cohort of 751 women with PCOS as well as ovulatory controls, which was a convenient sample of women attending for infertility or menstrual disorders, was also studied.

METHODS

The serum samples were assayed for AMH by the automated Access AMH assay.

MAIN OUTCOME MEASURES

Age-specific reference ranges were constructed on the primary cohort with the Lambda-Mu-Sigma method. The MoM AMH of each subject in the validation cohort was calculated.

RESULTS

Centile curves of serum AMH level against age were established. MoM AMH was significantly higher in women with PCOS than in controls (P < 0.05). The area under the ROC curve was 0.852 (95% confidence interval [CI] 0.825-0.877) (P < 0.0001) for discriminating women with PCOS from ovulatory controls by MoM AMH.

CONCLUSIONS

We established a set of year-by-year age-specific reference ranges of serum AMH levels in Chinese women. The MoM AMH derived from this set of reference ranges is a promising tool to replace antral follicle count in the diagnosis of PCOS.

TWEETABLE ABSTRACT

A set of age-specific reference ranges of AMH levels was established in Chinese women. Multiples of median AMH may be used to diagnose PCOS.

Intention of having a second child among infertile and fertile women attending outpatient gynecology clinics in three major cities in China: a cross-sectional study

STUDY QUESTION

What is the intention to have a second child among women attending outpatient gynecology clinics in three major cities in China?

SUMMARY ANSWER

In total, 69.3% of the participants expressed the intention to have a second child and this was related to infertility status, pronatalist attitudes, and sociodemographic factors.

WHAT IS KNOWN ALREADY

In 2016, the new universal two-child policy was introduced in China enabling all Chinese couples to have a second child. A government-led national survey revealed that the majority of women included under the policy would be 35 years old and older and thus would be at higher risk of infertility. Previous studies found that fertility intention differs by infertility status.

STUDY DESIGN, SIZE, DURATION

A cross-sectional survey was performed to examine the intention of having a second child and its associated factors among infertile and fertile women attending gynecology outpatient clinics in three major cities in China. Clinical nurses approached eligible women in person while waiting for their consultations. Recruitment and data collection were conducted from April to August 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The survey involved four gynecology outpatient clinics in Beijing, Shenzhen, and Hohhot. Married women aged 20–45 years who were seeking outpatient gynecology care for non-malignant problems were invited to participate.

MAIN RESULTS AND THE ROLE OF CHANCE

Data from 974 women were included in the analysis. A total of 69.3% of the women expressed the intention to have a second child, and infertile women were more likely to want a second child compared to fertile women (76.6% vs 61.9%, respectively; P < 0.001). Greater ideal parity facilitated the intention for a second child in both groups, while pronatalist attitudes (meaning that they preferred to have their first childbirth at a younger age and attached greater significance to traditional childbearing beliefs), unexplained infertility, presence of a living child and religious affiliation were associated with greater intention among infertile women. In contrast, in the fertile group, older age, full-time work and lower confidence in achieving parity goals diminished the intention for a second child. Although infertile women displayed greater agreement with pronatalist attitudes and desired a higher ideal parity, they had less confidence in achieving their parity goals than their fertile counterparts.

LIMITATIONS REASONS FOR CAUTION

In addition to self-report and self-selection bias, our participants were recruited from urbanized areas and were more educated than the general population. Owing to the extremely busy environment in the clinics, difficulties were encountered in keeping track of the number of women whom the nurses approached, and the response rate was therefore unavailable.

WIDER IMPLICATIONS OF THE FINDINGS

With the introduction of the universal two-child policy, there is a need to enhance fertility awareness and to encourage reproductive life planning, as well as to lower the cost of childcare, in order to increase the birth rate in China. Effort is required to make childbearing more compatible with current employment, career and educational development, the burdens of family care (e.g. for elderly parents), social environments and cultural expectations. This is particularly relevant for families who already have a child, as our findings show that their hesitation toward a second child was largely related to difficulties with extra childcare within the woman’s current work and family life.

STUDY FUNDING/COMPETING INTEREST(s)

This study did not receive any funding. The authors declared no competing interests.

TRIAL REGISTRATION NUMBER

Not applicable.

Whole‑exome sequencing analysis of products of conception identifies novel mutations associated with missed abortion

Missed abortion (MA) refers to a pregnancy in which there is fetal demise without outside intervention, and additionally no uterine activity that may expel the product of conception (POC) prior to 20 weeks of gestation. Chromosomal abnormalities are the primary cause of MA and single gene defects in the POC may additionally be associated with MA; however, few studies have been conducted on the identification of mutations by whole-exome sequencing. In the present study, 19 unrelated MA POCs were collected and whole-exome sequencing was performed on the POC. Bioinformatics analysis was performed on sequence variants from a list of 286 selected candidate genes that were associated with early embryonic lethality and MA. A total of 36 sequence variants in 32 genes potentially associated with MA were identified in 15 out of 19 patients. Gene Ontology analysis suggested that these genes were enriched in biological processes in early embryonic development, including ‘chordate embryonic development’, ‘cell proliferation’ and ‘forebrain development’. Further strict in silico bioinformatics analysis predicted that the LIM domain-binding protein 1 (c.662C>T; p.S221L) variant was a highly pathogenic variant. In conclusion, the results of the present study provide researchers and clinicians with a better understanding of the etiology and molecular mechanism of human embryonic lethality and MA.

A RHAG point mutation selectively disrupts Rh antigen expression

OBJECTIVES

The aim of this study was to characterise a novel mutation in the gene encoding RhAG in order to elucidate a molecular mechanism for Rh antigen expression and spherocytosis.

BACKGROUND

Rhesus-associated glycoprotein (RhAG) is critical for maintaining the structure and stability of erythrocytes. Single missense mutations in the gene encoding RhAG are sufficient to induce spherocytosis and deficiencies in Rh complex formation. We report a novel missense mutation that incompletely disrupts Rh antigen expression and selectively knocks out RhD antigen expression.

METHODS

Blood samples were taken from a 38-year-old male, his brother, his wife and his daughter in Xi'an, China. To detect the proband's RhAG and D antigen expression, the RBC were stained with anti-D and anti-RhAG and analysed by flow cytometry. Red blood cell morphology was detected with atomic force microscopy (AFM). Genomic DNA was isolated from whole blood samples, and the RHD, RHCE and RHAG alleles were sequenced and analysed. The mutation was mapped onto a predicted crystal structure of RhAG by the I-TASSER server and visualised using PyMOL.

RESULTS

Morphological testing by AFM found clear evidence of spherocytosis in the proband's erythrocytes. RHAG gene sequencing identified the mutation at sequence 236G > A, resulting in a serine to asparagine substitution at residue 79 (S79N). Family survey indicated that inheriting this allele is necessary and sufficient to cause the condition. Mapping the mutation onto a predicted crystal structure of RhAG revealed the proximity of the mutation to the critical structural elements of the protein.

CONCLUSIONS

A novel RHAG mutation significantly lowers RhAG antigen expression and antigen-mediated agglutination intensity.

Surface-induced spin state locking of the [Fe(H2B(pz)2)2(bipy)] spin crossover complex

Temperature- and coverage-dependent studies of the Au(1 1 1)-supported spin crossover Fe(II) complex (SCO) of the type [Fe(H2B(pz)2)2(bipy)] with a suite of surface-sensitive spectroscopy and microscopy tools show that the substrate inhibits thermally induced transitions of the molecular spin state, so that both high-spin and low-spin states are preserved far beyond the spin transition temperature of free molecules. Scanning tunneling microscopy confirms that [Fe(H2B(pz)2)2(bipy)] grows as ordered, molecular bilayer islands at sub-monolayer coverage and as disordered film at higher coverage. The temperature dependence of the electronic structure suggest that the SCO films exhibit a mixture of spin states at room temperature, but upon cooling below the spin crossover transition the film spin state is best described as a mix of high-spin and low-spin state molecules of a ratio that is constant. This locking of the spin state is most likely the result of a substrate-induced conformational change of the interfacial molecules, but it is estimated that also the intra-atomic electron-electron Coulomb correlation energy, or Hubbard correlation energy U, could be an additional contributing factor.

First Report of Gray Mold of Rhizoma paridis Caused by Botrytis cinerea in China

Rhizoma paridis is a perennial, traditional Chinese medicinal herb. In May 2013, a disease was observed in an approximately 10 ha cultivated field in Enshi, Hubei Province, China. Approximately 80% of plants in the field were affected. Symptoms were visible on the basal leaves of affected plants. Chlorosis followed by necrosis started at the leaf tips and margins and gradually spread inward until the entire leaf was necrotic. Thick, gray mycelium and conidia were visible on both sides surface of leaves under wet, humid conditions. The leading edge of the chlorotic leaves was excised from 20 plant samples surface disinfested with 1% NaOCl solution for 1 min, rinsed in sterile water, air dried, and placed on potato dextrose agar (PDA). Plates were incubated at 22°C in the dark. Mycelia were initially hyaline and white, and became dark gray after 72 h. Mycelia were septate with dark branched conidiophores. Conidia were smooth, hyaline, ovoid, aseptate, and ranged from 8 to 14.5 × 7 to 8.5 μm. Numerous hard, small, irregular, and black sclerotia that were 1 to 3 × 2 to 5 mm were visible on PDA plates after 12 days. The fungus was identified as Botrytis cinerea on the basis of these characters (1). The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS1 and ITS4 primer and sequenced (GenBank Accession No. KF265499). BLAST analysis of the PCR product showed 99% identity to Botryotinia fuckeliana (perfect stage of B. cinerea) (EF207415.1, EF207414.1). The pathogen was further identified to the species level as B. cinerea using gene sequences from glyceraldehyde-3-phosphate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60), and DNA-dependent RNA polymerase subunit II (RPB2) (2) (KJ638600, KJ638602, and KJ638601). Pathogenicity was tested by spraying the foliage of 40 two-year-old plants with a suspension of 10⁶ conidia per ml of sterile distilled water. Each plant received 30 ml of the inoculum. Ten healthy potted plants were inoculated with sterilized water as control. All plants were covered with plastic bags for 5 days after inoculation to maintain high relative humidity and were placed in a growth chamber at 22°C. The first foliar lesions developed on leaves 7 days after inoculation and were similar to those observed in the field. No symptoms developed on the control plants. B. cinerea was consistently re-isolated from all artificially inoculated plants. The pathogenicity test was completed twice. To our knowledge, this is the first report of gray mold of R. paridis caused by B. cinerea in China. The root of R. paridis is the most commonly used Chinese herbal medicine to treat viper bites. In recent years, cultivation of this herb has increased in China because of its high value. Consequently, the economic importance of this disease is likely to increase with the greater prevalence of this host species. References: (1) H. L. Barnett and B. B. Hunter. Illustrated Genera of Imperfect Fungi. Burgess Publishing Company, Minneapolis, MN, 1972. (2) M. Staats et al. Mol. Biol. Evol. 22:333, 2005.

Comparison of static and dynamic knee kinematics during squatting

BACKGROUND

there long has been debate whether static knee kinematics measured using magnetic resonance imaging are the same as knee kinematics in dynamic weight-bearing motion. Magnetic resonance imaging provides excellent volumetric detail but is static. Fluoroscopic imaging provides for dynamic observation of knee kinematics but provides no direct observation of the soft-tissue structures. We attempted to answer the question 'Are knee kinematics the same during static and dynamic squatting?'

METHODS

knee kinematics data from two previously reported studies of healthy knee kinematics during squatting from 0° to 120° were obtained. The results of the dynamic fluoroscopic study were reformatted to perform a direct comparison of femoral anteroposterior translation and internal-external rotation with the static magnetic resonance imaging study.

FINDINGS

comparison of internal-external rotations and lateral femoral condyle anteroposterior translations did not reveal significant differences between static and dynamic data. The medial femoral condyle demonstrated 0 (SD=3) mm posterior translation during dynamic squatting from 0° to 120° flexion compared to 5 (SD=3) mm posterior translation during static squatting (P=0.01, Cohen's d=1.7).

INTERPRETATION

for squatting types of motions, static and dynamic study protocols appear to produce equivalent knee kinematics with no functionally important differences. Differences in medial condyle translations can be attributed to differences in foot position during the study. Investigators can choose the modality that best fits their goals and resources with the knowledge that the results for squatting activities are comparable.

Endovascular treatment of huge dissecting aneurysms involving the basilar artery. Experience and lessons from two cases

SUMMARY

Dissecting aneurysms involving the basilar artery (BA) are lesions with significant morbidity and mortality. Their management is controversial and often difficult. There is no generally approved strategy. Two cases of huge dissections involving the BA presented with subarachnoid hemorrhage in one case and mass effect in both cases. The dissection of case 1 involved the upper two thirds of the BA distal to the anterior inferior cerebellar arteries (AICA). Another dissection of case 2 involved the bilateral vertebral arteries (VA) distal to bilateral PICA and extended to upper third of the BA. After making a basket with coils inside the pseudoaneursym, proximal dissection was totally occluded in case 1. Dissection on the bilateral VA distal to the bilateral PICA and proximal BA was occluded in case 2 with a small residual dissection on the left VA. Case 1 had an excellent recovery with a durable image and clinical result. But recanalization and regrowth occurred in case 2, which might have originated from the residual dissection on the left VA, induced acute mass effect and sudden coma six weeks after the initial treatment. The residual and regrown dissection had to be occluded in a second intervention. The patient died two days later. BA occlusion is safe and efficient for dissections involving the BA as in our case and the literature. Proximal occlusion might be enough for huge and long lesions like ours. It seems that completely dense packing of proximal dissection is the key point to prevent recanalization.

Bidirectional on/off switch for controlled targeting of proteins to subcellular compartments

A regulatable fusion protein was constructed for controlling the localization of plasmid products. A ligand-inducible nuclear localization signal, nuclear export signal (NES) and a truncated form of the ligand binding domain of the progesterone receptor were attached to the desired protein. Enhanced green fluorescent protein (EGFP) was used as a model protein and its trafficking between the nucleus and cytoplasm was studied using fluorescence microscopy in response to the ligand, mifepristone. It was found that the protein trafficking into the nucleus was dose dependent with ligand concentration. Increasing the ligand dose from 1 to 100 nM enhanced import and reduced the rate of export of the fusion protein from the nucleus to the cytoplasm. This study demonstrates the feasibility of using an export signal and a ligand-inducible nuclear import signal as a bi-directional on/off switch with potential use for controlled targeting of therapeutic proteins to subcellular compartments.

Asbestos related diseases from environmental exposure to crocidolite in Da-yao, China. I. Review of exposure and epidemiological data

BACKGROUND

Scattered patches of crocidolite, one form of asbestos, were found in the surface soil in the rural county of Da-yao in southwestern China. In 1983, researchers from the West China University of Medical Sciences (WCUMS) discovered that residents of two villages in Da-yao had hyperendemic pleural plaques and excessive numbers of pleural mesotheliomas.

AIMS

To review and summarise epidemiological studies, along with other relevant data, and to discuss the potential contribution to environmental risk assessment.

METHODS

This report is based on a review of several clinical/epidemiological studies conducted by WCUMS researchers since 1984, which included one cross sectional medical examination survey, one clinical/pathological analysis of 46 cases of mesothelioma, and three retrospective cohort mortality studies. Additional information acquired from reviewing original data first hand during a personal visit along with an interview of medical specialists from Da-yao County Hospital was also incorporated.

RESULTS

The prevalence of pleural plaque was 20% among peasants in Da-yao over 40 years of age in the cross sectional survey. The average number of mesothelioma cases was 6.6 per year in the 1984-95 period and 22 per year in the 1996-99 period, in a population of 68 000. For those mesothelioma cases that were histology confirmed, there were 3.8 cases/year in the first period and 9 cases/year in the second. Of the 2175 peasants in this survey, 16 had asbestosis. Lung cancer deaths were significantly increased in all three cohort studies. The annual mortality rate for mesothelioma was 85 per million, 178 per million, and 365 per million for the three cohort studies, respectively. The higher exposed peasants had a fivefold increased mesothelioma mortality compared to their lower exposed counterparts. There were no cases of mesothelioma in the comparison groups where no crocidolite was known to exist in the environment. In the third cohort study, almost one of five cancer deaths (22%) was from mesothelioma. The ratio of lung cancer to mesothelioma deaths was low for all three studies (1.3, 3.0, and 1.2, respectively).

CONCLUSIONS

The observation of numerous mesothelioma cases at Da-yao was a unique finding, due mainly to their lifetime exposure to crocidolite asbestos. The finding of cases dying at a younger age and the relatively high ratio of mesothelioma cases to lung cancer could also be another unique result of lifetime environmental exposure to crocidolite asbestos. Although the commercial use of crocidolite has been officially banned since 1984, the incidence of mesothelioma has continued to show a steady increase, particularly among peasants. Since the latency of mesothelioma is approximately 30-40 years, the ban had little effect in the 1990s. The increased awareness and changes in diagnosis over time may also contribute to the increase. Furthermore, exposure to asbestos stoves and walls continued. The government implemented reduction of these exposures. However, from a public health standpoint, the most important issue is the complete avoidance of further exposure to asbestos.

WSX-1 is required for the initiation of Th1 responses and resistance to L. major infection

WSX-1 is a class I cytokine receptor with homology to the IL-12 receptors. The physiological role of WSX-1, which is expressed mainly in T cells, was investigated in gene-targeted WSX-1-deficient mice. IFN-gamma production was reduced in isolated WSX-1(-/-) T cells subjected to primary stimulation in vitro to induce Th1 differentiation but was normal in fully differentiated and activated WSX-1(-/-) Th1 cells that had received secondary stimulation. WSX-1(-/-) mice were remarkably susceptible to Leishmania major infection, showing impaired IFN-gamma production early in the infection. However, IFN-gamma production during the later phases of the infection was not impaired in the knockout. WSX-1(-/-) mice also showed poorly differentiated granulomas with dispersed accumulations of mononuclear cells when infected with bacillus Calmette-Guerin (BCG). Thus, WSX-1 is essential for the initial mounting of Th1 responses but dispensable for their maintenance.

[Effects on fiber regeneration following facial nerve transection treated with NOS antagonist]

OBJECTIVE

To elucidate the role of nitric oxide synthase antagonist, N-Nitro-L-Arginine Methyl Ester (L-NAME) in the regeneration of facial nerve following facial nerve transection.

METHOD

The facial nerves of 40 guinea pigs were exposed and a segment of the nerve at 3 mm length were excided. The two ends of the transected nerve were sutured and enveloped in a silicone tubule to form a regeneration chamber. L-NAME and saline were respectively injected into the regeneration chambers just after transection. The experiments were observed quantificational by the means of axon and myelin staining under light microscope.

RESULT

The findings in the work indicate that inhibition of NOS with L-NAME substantially better myelinated facial nerve regeneration than that associated with administration of saline.

CONCLUSION

L-NAME improve the regeneration of myelinated fibers. The mechanism seems to be related to the blockade of NO's neurotoxicity.

[Acoustic densitometry for quantification of renal allografts microcirculation and microstructure]

OBJECTIVE

To establish a new method for observing renal allografts microcirculation and microstructure with acoustic densitometry (integrated backscatter, contrast, second harmonics).

METHODS

27 patients with renal allografts were investigated by Doppler, IBS, contrast and second harmonics. Renal allografts failed age in 5 patients 20-61 years. Intravenous injection of SHU-508A was given, compared with pre-injection by quantitative assessment of acoustic densitometry (AD) of renal microstructure.

RESULTS

There was a significant difference in the peak intensity, the area under the curve and the half-time of wash-out between pre-injection and injection contrast agent. The wish-in and wish-out curve was shown in a peak shape. The renal allografts with acute rejection were significantly lower than the control group in AD (P < 0.05). No contrast opacification of renal microstructure was present in 5 failed renal allografts and the wish-in and wish-out curve appeared in a straight line shape.

CONCLUSION

AD is safe, and efficient in assessing renal allografts microstructure. It more sensitive in detecting allograft complication such as rejection than Doppler.

Ectopic overexpression of c-mpl by retroviral-mediated gene transfer suppressed megakaryopoiesis but enhanced erythropoiesis in mice

In this report, we tested whether ectopic overexpression of a cell surface receptor cDNA could be used to explore the physiological roles of that receptor. We generated c-mpl overexpressing animals by reconstituting mice with retroviral vector-transduced bone marrow (BM) cells. We observed that platelet counts in the c-mpl overexpressing mice failed to recover to normal levels and remained at <200 x 10(6)/mL post-transplantation, while platelet numbers in the control mice returned to > 800 x 10(6)/mL by 4 weeks post-transplantation. However, platelet counts in the c-mpl overexpressing mice could be stimulated to normal levels after administration of rhMGDF. No significant changes in peripheral leukocyte counts were observed, although the number of CFU-E, GM-CFC, and CFC-multi were reduced two- to threefold in the BM of the c-mpl overexpressing mice. In addition, enhanced erythropoiesis was observed in the c-mpl overexpressing mice. The mpl receptors on erythroid cells were functional as demonstrated by tyrosine-phosphorylation of mpl receptor on RBC and by in vitro erythroid colony-formation in response to MGDF stimulation, respectively. These results suggested that ectopically expressed mpl receptors competed for ligand in vivo leading to an insufficient amount of circulating thrombopoietin (Tpo) for the development of megakaryocytic lineage. These results further suggest that, in addition to sequestering circulating Tpo, overexpression of the mpl receptor on erythroid progenitors may directly contribute to enhanced erythropoiesis in vivo. Our studies demonstrate that ectopic overexpression of a receptor by retroviral-mediated gene transfer provides an approach to explore the biological roles of novel receptors.

[Investigation and analysis of the diagnostic status of bronchial asthma]

OBJECTIVE

The aim of this study was to investigate the rate of delayed diagnosis of the bronchial asthma and related factors.

METHOD

57 asthmatic outpatients were investigated randomly by questionnaire including main symptoms of asthmatic attack, the date of initial attack, the date of initial visit physician, and initial diagnosis, the basis of diagnosis and the names of misdiagnosed diseases. Then according to the above-mentioned data the duration of delayed diagnosis, the rate of delayed diagnosis were calculated.

RESULT

96% of outpatients saw physician within 1 yr. after initial attack. The duration from initial visit to making diagnosis were 11.1 +/- 2.3, and 1.5 +/- 0.3 yr. before and after 1980, respectively, and their rate of delayed diagnosis were 75%, 15%, respectively. Both of their differences were statistically significant (P < 0.01). Only 20% of diagnosis of asthma was by pulmonary function test.

CONCLUSION

The majority of the delayed diagnosis should be due to making the mis-understanding and underattention of physician to the asthma, and their diagnostic levels should need further improving.

[The risk of lung cancer and mesothelioma in farmers exposed to crocidolite in environment]

To assess the risk of lung cancer and mesothelioma after environmental exposure to crocidolite for 20-30 years, a retrospective cohort study was carried out in farmers who had been exposed to crocidolite in environment. 1610 subjects were followed up for 9 years (Jan. 1, 1987 Dec. 31, 1995). The control group consisted of 7646 farmers who resided in the noncrocidolite pollution rural area in the same province. The results showed that the annual mortality rate was 43.75 per 100,000 population for lung cancer, and 36.46 per 100,000 for mesothelioma. Significantly high risks of lung cancer (RR 5.67) and mesothelioma (RR 182.3) were noted. These results demonstrate a strong causal association between lung cancer, mesothelioma and exposure to crocidolite.

Chronic exposure to retroviral vector encoded MGDF (mpl-ligand) induces lineage-specific growth and differentiation of megakaryocytes in mice

Megakaryocyte growth and development factor (MGDF) has recently been identified as a ligand for the c-mpl receptor. Using retroviral-mediated gene transfer, MGDF has been overexpressed in mice to evaluate the systematic effects due to chronic exposure to this growth factor. MGDF overexpressing mice had more rapid platelet recovery than control mice after transplantation. Following this recovery, the platelet levels continued increasing to fourfold to eightfold above normal baseline levels and remained elevated (five-fold above control mice) in these animals, which are alive and well at more than 4 months posttransplantation. Increased megakaryocyte numbers were detected in a number of organs in these mice including bone marrow, spleen, liver, and lymph nodes. Prolonged overexpression of MGDF led to decreased marrow hematopoiesis, especially erythropoiesis, with a shift to extramedullary hematopoiesis in the spleen and liver. All the MGDF overexpressing mice analyzed to date developed myelofibrosis and osteosclerosis, possibly induced by megakaryocyte and platelet produced cytokines. No significant effect on other hematopoietic lineages was seen in the MGDF overexpressing mice, showing that the stimulatory effect of MGDF in vivo is restricted to the megakaryocyte lineage.

The tsA58 simian virus 40 large tumor antigen disrupts megakaryocyte differentiation in transgenic mice

Thrombocytopenia is a condition of multiple etiologies affecting the megakaryocyte lineage. To perturb this lineage in transgenic mice, the tsA58 mutation of the simian virus 40 large tumor antigen was targeted to megakaryocytes using the platelet factor 4 promoter. Ten of 17 transgenic lines generated exhibited low platelet levels, each line displaying a distinct, heritable level of thrombocytopenia. Within a line, the degree of the platelet reduction correlated directly with transgene zygosity. The platelet level could be further reduced by the inactivation of one copy of the endogenous retinoblastoma gene. Western blot analysis detected large tumor antigen protein in the most severely affected lines; less affected lines were below the level of detection. Platelets and megakaryocytes from thrombocytopenic mice exhibited morphological abnormalities. Mice with either normal or reduced platelet levels developed megakaryocytic malignancies with a mean age of onset of about 8 months. There was no correlation between severity of thrombocytopenia and onset of malignancy. These mice provide a defined genetic model for thrombocytopenia, and for megakaryocytic neoplasia, and implicate the retinoblastoma protein in the process of megakaryocyte differentiation.

Purification and properties of a diisopropyl-fluorophosphatase from squid Todarodes pacificus steenstrup

A diisopropyl-fluorophosphatase (DFPase) was purified from brain and ganglia of squid Todarodes pacificus steenstrup. The DFPase had a preference in hydrolysis toward diisopropylphosphorofluoridate (DFP). It also was able to hydrolyze O-1,2,2-trimethylpropyl methylphosphofluoridate (soman) and O-isopropyl methylphosphonofluoridate (sarin) at nearly equal hydrolytic rates but only 1/10 that of DFP. The hydrolytic activity toward diethyl-p-nitrophenylphosphate (paraoxon) was very low compared with DFP, soman, and sarin. The DFPase was purified 330-fold to a specific activity of 18,300 n mol/min/mg protein. Its molecular weight was 34,000 dalton determined by gel-filtration chromatography. Mn2+ stimulation of the DFPase was not observed when DFP and soman were the substrates, but with sarin, the rate increased onefold in the presence of 1.0 mM of Mn2+. Ethylenediamine tetraacetic acid disodium (EDTA-Na2) at 0.05 M inhibited the DFPase activity about 30%. It could be concluded that this DFPase belongs to the squid-type DFPase.

[Study on relationship between human ABO blood groups and type A behavior pattern]

Investigation of the relationship between ABO blood groups (ABO BG) and Type A behavior pattern (TABP) was performed. No significant correlation was found between human ABO BG and TABP (P less than 0.05). However, CH and TH + CH scores in individuals with blood type A and type A personality were significantly lower (P less than 0.05). The values of TH-CH scores among tested people were of no statistical significance (P greater than 0.05). Moreover, nearly half of the examinees (41.32%) had higher CH score and the distribution of the individuals was obviously different in statistics (P less than 0.005). In addition, L score of examinees with blood type A and type B personality was relatively lower.