High-peak-power optically pumped passively mode-locked semiconductor laser with minimal components.

A high-peak-power sub-500-fs mode-locked optically pumped semiconductor laser is innovatively developed with only three components of a semiconductor gain chip, a semiconductor saturable absorber, and a focusing lens. The developed laser near the threshold pump power of 3.9 W can be operated with stable fundamental mode locking. The laser output can be naturally turned into the stable harmonic mode locking (HML) with the order gradually changing from 2nd to 8th by increasing the pump power from 4.0 W to 5.0 W. Due to the onset of the high-order transverse modes, the order of HML is fixed at 8th for a pump power greater than 5.0 W. For the HML with order less than 8th, the overall peak power and pulse width in the HML are approximately 0.36 kW and 550 fs, respectively. In the operation of 8th-order HML, the minimum pulse width and maximum peak power can reach 480 fs and 0.95 kW, respectively.

Association between the Lymphocyte-to-C-Reactive Protein Ratio and Survival Outcomes in Cancer Patients with GLIM-Defined Malnutrition: A Multicenter Study.

BACKGROUND AND AIMS: This study assessed the prognostic value of LCR in patients with cancer-associated malnutrition (CAM). Systemic inflammatory markers, particularly the lymphocyte-to-C-reactive protein ratio (LCR), are related to the survival of patients with CAM. The present retrospective analysis based on a prospective multicenter cohort study, which involved 1,437 hospitalized patients with CAM. METHODS: The area under the receiver operating characteristic curve (AUC) of ten inflammatory indicators-LCR, advanced lung cancer inflammation index, neutrophil-to-lymphocyte ratio, prognostic nutritional index, modified Glasgow prognostic score, systemic immune-inflammation index, albumin-to-globulin ratio, LCR score, glucose-to-lymphocyte ratio, and platelet-to-lymphocyte ratio-were constructed. Nutritional status, blood markers, and quality of life (QoL) were evaluated within 48 h of admission. The overall survival (OS) was evaluated from September 1 to December 29, 2021. RESULTS: A total of 1,431 cancer patients diagnosed with malnutrition based on the Global Leadership Initiative on Malnutrition (GLIM) criteria. Male patients were 62.8% of all, and the mean age was 60.66 years old. The AUC of LCR was higher than that of other inflammatory markers. The restricted cubic spline (RCS) of the Hazard ratios (HRs) showed an inverse L-shaped relationship with LCR. In addition, patients with low LCR had significantly poorer OS than those with high LCR. The addition of LCR to the model increased the predictive ability of 1-year mortality (AUC increase of 0.036), 3-year mortality (AUC increase of 0.038), and 5-year mortality (AUC increase of 0.031). CONCLUSIONS: Assessing the LCR can help the medical staff identify cancer patients with nutritional deficiency at high risk of oncological outcomes and develop individualized therapeutic strategies.

[Trends of the disease burden of intellectual disability among children and adolescents from 1990 to 2019 in China].

Objective: This study aims to analyze the disease burden of intellectual disability among Chinese children and adolescents aged 0-19 years in 2019 and its trends from 1990 to 2019. Methods: Data were gathered from the Global Burden of Disease study. The prevalence and years lived with disability (YLDs) of intellectual disability among Chinese children and adolescents were compared with the global average by gender, age group, and severity of disability in 2019. Joinpoint regression model was used to analyze the trends in the prevalence and YLDs of intellectual disability among Chinese children and adolescents from 1990 to 2019. Results: The prevalence and YLDs of intellectual disability among Chinese children and adolescents in 2019 were 1 522.65 per 100 000 (95%UI: 1 228.62 per 100 000-1 817.55 per 100 000) and 109.81 per 100 000 (95%UI: 72.15 per 100 000-158.09 per 100 000), respectively, which were lower than the global average. The prevalence and YLDs of severe intellectual disability in China were slightly higher than the global average. The average annual percent changes in the prevalence and YLDs of intellectual disability among Chinese children and adolescents were -0.23% (95%CI: -0.26%--0.21%, P<0.001) and 0.74% (95%CI: 0.66%-0.81%, P<0.001) from 1990 to 2019, respectively. The prevalence and YLDs of severe intellectual disability showed continuously increasing trends over the past 30 years. Conclusions: The disease burden of intellectual disability among Chinese children and adolescents was lower than the global average in 2019, but severe intellectual disability was higher than the global average. The prevalence of intellectual disability among Chinese children and adolescents showed an overall decrease, while YLDs showed an increasing trend from 1990 to 2019.

[Effects of menopause on depressive and anxiety symptoms in community women in Beijing].

Objective: To determine the effects of menopausal stage, age and other associated risk factors on symptoms of anxiety and depression among women in a community in Beijing. Methods: This study was a community-based prospective cohort. Participants who had transitioned through natural menopause, completed two or more depressive and anxiety symptoms evaluations, aged 35 to 64 years, and did not use hormone therapy were selected from the Peking Union Medical College Hospital aging longitudinal cohort of women in midlife to this analysis. The primary outcome variables were depressive and anxiety symptoms, assessed by hospital anxiety and depression scale (HADS). The generalized estimation equation was used in the statistical analysis. Results: Followed up from 2006 to 2014, 430 women and 2 533 HADS assessments were retained in the cohort. Depressive symptoms were more common than anxiety symptoms during all menopausal stages. The incidences of depressive and anxiety symptoms were 14.5% (19/191) and 3.1% (4/191) in the premenopausal -3 stage, respectively. The incidence increased in both menopausal transition and postmenopausal stage, with the highest incidence in the +1c stage [20.6% (155/751) and 8.8% (66/751), respectively]. However, these differences were not statistically significant (all P>0.05). Depressive symptoms were highest in the ≥60-<65 age group [20.8% (74/355)], and anxiety symptoms were highest in the ≥50-<55 age group [8.2% (62/754)]; but there were no statistical significances between different age groups and depressive and anxiety symptoms (all P>0.05). Multivariable analysis showed that high body mass index, low education status, and poor health status were independently associated with depressive symptoms (all P<0.05), and that poor health status, trouble falling asleep, and early awakening were independently associated with anxiety symptoms (all P<0.01). Conclusions: Depressive and anxiety symptoms are more common during menopausal transition and postmenopausal stage compared with reproductive stage. Depressive symptoms are more common than anxiety symptoms. To screen and assess depressive and anxiety symptoms in perimenopausal women is essential, especially for women with high risk factors.

[A cohort study on the influence of the chronic diseases on falls among middle-aged and older Chinese].

Objective: To analyze the influence of chronic diseases on falls among middle-aged and older Chinese. Methods: Baseline data of 13 670 middle-aged and older adults recruited from China Health and Retirement Longitudinal Study (CHARLS) in 2011 were used and followed up to 2018, among those were 7 443 (54.45%) middle-aged people aged 45-59 and 6 227 (45.55%) older adults aged 60 and above. The Cox proportional hazards model was used to analyze the effects of different types, the number of chronic diseases and the interaction between chronic illness and other factors on the fall risk of middle-aged and older people. Results: After adjusting for confounding factors, respiratory diseases increased the risk of falls by 21% (HR=1.21, 95%CI:1.02-1.45), and arthritis increased the risk of falls by 27% (HR=1.27,95%CI: 1.12-1.43) in the group aged 45-59, kidney disease increased the risk of falls by 26% (HR=1.26, 95%CI: 1.03-1.53) in the group aged 60 and above. A linear dose-response relationship between the number of chronic diseases and fall risk (χ2=133.61, P<0.001) was found in all the age groups. The interaction between having chronic diseases and the factors of females (HR=1.64, 95%CI: 1.43-1.89), impaired activities of daily living (ADL) (HR=1.66, 95%CI: 1.39-1.99), and having a fall history (HR=2.58, 95%CI: 2.24-2.97) increased the risk of falls. Conclusions: There is a positive linear relationship between the number of chronic diseases and the fall risk among Chinese aged 45 and above. The female middle-aged and elderly patients with chronic diseases and the middle-aged and elderly patients with impaired ADL or a history of falls are the high-risk groups for falls that need to be focused on intervention. The window of fall injury prevention should be moved forward to the middle-aged stage in time.

[A retrospective cohort study of the effects of the adverse childhood experience on chronic diseases of middle-aged and elderly].

Objective: To investigate the adverse childhood experience (ACE) effects on the risk of chronic diseases among middle-aged and elderly. Methods: A retrospective cohort study was conducted using the China Health and Retirement Longitudinal Study data. We used life history study data in 2014 as baseline data and data of chronic diseases of middle-aged and elderly in 2015 as outcomes. A zero-inflated negative-binominal model was used to estimate the incidence rate ratio (IRR) for the association between ACE and chronic diseases. Results: Compared with the less than 4 points of ACE exposure in childhood, individuals with ACE exposure 4-, 6- and ≥9 were associated an increased risk of chronic disease, adjusted IRR (95%CI), 1.10(1.04-1.16), 1.18 (1.13-1.25), 1.34 (1.27-1.42), respectively, with a significant dose-response relationship that chronic diseases risks increase parallel with the increase of ACE exposure. Conclusions: ACE might serve as one of the critical risk factors of chronic diseases in middle-aged elderly. It's of public health significance for early screening and intervention of ACE, reducing the incidence of chronic diseases, and improving middle-aged and older adults' quality of life and health.

[Clinical experience in transoral endoscopic thyroidectomy via sublingual and vestibular approach: a report of 98 cases].

Objective: To summarize the clinical experience in transoral endoscopic thyroidectomy via sublingual and vestibular approach (TOETSLVA). Methods: We retrospectively reviewed the medical record of patients who underwent TOETSLVA in our department from November 2011 to May 2020, including 3 males and 95 females, aged from 18 to 57 years old. Initial 81 cases were categorized in "Period A (November 2011-November 2015)" and subsequent 17 cases in "Period B (August 2019-May 2020)" . Data about demographics, operation time and complications were collected. SPSS 22.0 software was used for statistical analysis. Results: In Period A, the average age of patients was (34.2±9.4) years old; the mean tumor diameter was (2.33±0.80) cm; postoperative pathology showed benign nodules in 76 cases and malignant carcinoma in 5 cases; there were 65 cases of unilateral subtotal thyroid lobectomy, 6 cases of isthmus lobectomy, and 5 cases of bilateral subtotal thyroid lobectomy, with the mean operation time of (132.70±47.22) min; in 5 cases of unilateral thyroid lobectomy with central lymph node dissection, the mean operation time was (185.4±31.40) min; postoperative neck infections occurred in 6 cases; temporary vocal cord paralysis occurred in 1 case, which it recovered within two months; and CO(2) gas embolism occurred in 2 cases. In Period B, the average age of patients was (35.1±8.5) years old; mean tumor diameter was (1.32±0.67) cm; postoperative pathology indicated malignant nodules in 15 cases and benign nodules in 2 cases; in 2 cases of unilateral thyroid lobectomy, the mean operation time was (153.5±34.64) min; in 15 cases of unilateral thyroid lobectomy with central lymph node dissection, the mean operation time was (123.73±14.26) min; and none of patients developed postoperative neck infections or CO(2) gas embolism. All patients had different degree of cutaneous numbness in the submandibular region after surgery, which recovered within 1-2 weeks. There were no complications such as postoperative secondary hemorrhage, permanent vocal cord paralysis, hypoparathyroidism in both the periods. The median follow-up time was 86 months (57-105 months) in Peroid A and 5 months (3-12 months) in Peroid B. During the follow-up periods, there were no obvious abnormalities in swallowing, chewing, oral sensory function and neck activity, and also no tumor recurrence or metastasis. Conclusions: TOETSLVA is a safe and feasible surgery method, with a good cosmetic result. This approach will not lead to a postoperative cutaneous numbness of the submandibular region for a long time.

[Spatial distribution of low birth weight and association with chemical fertilizer application in rural areas of Shanxi province].

Objective: To explore the spatial distribution of low birth weight (LBW) and the potential environmental risk factors and provide the evidence for the prevention and intervention of LBW. Methods: Data were from a surveillance system for newly born population and adverse pregnancy outcome between 2007 and 2012 in Pingding county, Shanxi province. The data from 313 villages were analyzed. Spatial hierarchical Bayesian model was used to adjust the risk of LBW at village level, Moran's I and Getis-Ord Gi* were used to analyze the difference in distribution of LBW risk area. Spatial negative binomial model was used to evaluate the association between the risk of LBW and chemical fertilizer application. Results: A total of 18 749 new births were recorded between 2007 and 2012, including 911 LBW cases, the total incidence of LBW was 4.86%. The result of the spatial hierarchical Bayesian model showed that high-risk area of LBW was in the southeast of Pingding and low-risk area was in the middle west of Pingding. The result of Moran's I showed that there was a clustering pattern of LBW risk, and Getis-Ord Gi* found a high risk (hot spot) area in the south area. Moreover, the findings of association analysis showed that the risk of LBW increased with the increased chemical fertilizer application at village level. Conclusions: There were area specific differences in the risk of LBW, and dose-response relationship between chemical fertilizer application and the risk of LBW. Our findings suggest that maternal exposure to chemical fertilizer during pregnancy might be a potential risk factor for LBW in rural area.

[Associations between maternal exposure to chemical fertilizers during pregnancy and the risk of offspring's low birth weights].

Objective: To explore the association between the consumption of chemical fertilizers and the risk of low birth weight (LBW), to provide references for prevention programs on LBW and to improve the birth outcomes. Methods: Stratified multivariate logistic regression method was used in this study involving 153 preterm LBW infants, 179 term LBW infants and 204 normal control infants that were randomly selected from the birth monitoring data between October 2007 and September 2012 in Pingding county, Shanxi province. Associations between the risk of LBW and maternal exposure to chemical fertilizers during pregnancy were identified. A normal control group was set up to compare results between preterm and term LBW groups. Results: Totally, 18 749 infants were born between 2007 and 2012, with the total incidence rates of LBW as 48.5‰, preterm LBW as 19.4‰, and term LBW as 29.1‰. Concerning the case control study on preterm LBW, after adjustment for confounding factors, the risk of preterm LBW appeared 2.51 (95%CI: 1.05-5.99) times higher in villages with annual consumption of chemical fertilizer ≥100 tons than those villages that using chemical fertilizer less than 50 tons. No significant statistical associations were found between the amounts of household chemical fertilizer consumption and the risks of preterm LBW. Regarding the case control study on term LBW, after adjustment for confounding factors, in villages with ≥100 tons annual consumption of chemical fertilizers, the risk of term LBW was 4.03 (95%CI: 1.63-9.92) times of the risk in villages where the annal use of chemical fertilizers was less than 50 tons. There was no significant association between household consumption of chemical fertilizers and the risk of term LBW. Conclusions: Maternal exposure to chemical fertilizers during pregnancy was associated with the risk of LBW. Our findings suggested that the amount of chemical fertilizer consumption in rural areas seemed also associated with the risks of other adverse pregnancy outcomes. Women should avoid the chance of exposure to chemical fertilizers during pregnancy and the consumption of chemical fertilizers should be carefully managed.

Prevention of postmenopausal osteoporosis in Chinese women: a 5-year, double-blind, randomized, parallel placebo-controlled study.

OBJECTIVES: To observe the effectiveness and safety of menopause-related hormone therapy (MHT) to prevent bone loss in Chinese women during the menopausal transition and early menopause, as well as to evaluate the effects of 5-year MHT on overall health to add Level I evidence for the prevention of osteoporosis using MHT. DESIGN: This clinical study was a prospective, double-blind, randomized, parallel placebo-controlled study. Chinese women in the menopausal transition and early menopause were randomly allocated to the MHT group or the placebo group. All subjects received a 5-year intervention. The effectiveness of MHT for bone mineral density (BMD) and bone metabolism and the safety of MHT in relation to glycolipid metabolism, breast cancer, and cardiovascular disease were studied. RESULTS: In the MHT group, women in both transition and early menopause showed a significant increase in lumbar and femoral neck BMD after the 1st year of therapy; BMD tended to decrease in the 3rd year but ultimately was sustained at stable levels that were near the baseline levels. In the placebo group, BMD decreased at both sites. Metabolism indexes and breast ultrasound examination findings did not differ significantly between the MHT and placebo groups. Three cases of breast cancer and three cases of cardiovascular disease were diagnosed during follow-up. One breast cancer case and two cardiovascular disease cases occurred in the MHT group. CONCLUSIONS: Five-year sequential therapy with estrogen and progesterone can increase or maintain the BMD of women in their menopausal transition and early menopause. This regimen had no negative effect on glycolipid metabolism and did not increase the risk of breast cancer or cardiovascular events.

Inhibitory effect of ursolic acid and oleanolic acid from Eriobotrya fragrans on A549 cell viability in vivo.

Loquat [Eriobotrya japonica (Lindl.)] is a traditional Chinese medicine, which has been used as an anti-inflammatory and for curing chronic bronchitis among other potential applications. Extracted ursolic acid (UA) and oleanolic acid (OA) from wild loquat were previously found capable of suppressing the proliferation of A549 cells in vitro. In the current study, nude mice were used to determine the inhibitory effect of UA and OA on tumor formation in vivo. The results demonstrate that UA and OA reduced the proliferation of A549 cells in nude mice, and increased the expression of Bid while decreasing the protein levels of MMP-2, Ki-67, and CD34. In this study, we identified potential antitumor activity in a wild loquat extract containing UA and OA, which demonstrates that traditional Chinese medicine may have a role in treating certain types of cancer.

The response of meat ducks from 15 to 35 d of age to gossypol from cottonseed meal.

The objective of this study was to investigate the responses of meat ducks of 15 to 35 d of age to free gossypol (FG) from cottonseed meal (CSM) and to establish the maximum limits of dietary FG concentration based on growth performance, blood parameters, and tissue residues of gossypol. Nine hundred 15-d-old ducks were randomly allocated to 5 treatments with 10 cages/treatment and 18 ducks/cage on the basis of BW. Five isonitrogenous and isocaloric experimental diets were formulated on a digestible amino acid basis to produce diets in which 0% (without FG), 25% (36 mg FG/kg), 50% (75 mg FG/kg), 75% (111 mg FG/kg), and 100% (153 mg FG/kg) of protein from soybean meal were replaced by that from CSM. Increasing dietary FG content, BW, and ADG decreased (linearly, P<0.05, except for ADG of days 29 to 35), and F/G linearly increased (P<0.05). At 35 d, blood hemoglobin, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration linearly decreased (P<0.05), while serum total protein, albumin, and globulin content linearly decreased (P<0.05), and the residue of gossypol in liver, kidney, heart, breast, and leg muscle linearly increased (P<0.001) with increases in dietary FG concentration. Ducks fed 36 mg FG/kg (5.83% CSM of diet) diet had a normal histological structure of liver, and muscle (breast and leg) had no residue of gossypol. The maximum limit of dietary FG concentration was estimated to range from a low of 36 mg/kg to maximize serum globulin concentration to a high of 124 mg/kg to minimize feed intake for 22 to 28 d on the basis of a quadratic broken-line model.

The effect of age and menopausal status on musculoskeletal symptoms in Chinese women aged 35-64 years.

OBJECTIVE: To assess the prevalence of musculoskeletal symptoms at four different anatomical sites and the impact of menopause, age, and other factors on musculoskeletal symptoms. METHODS: Generally healthy women aged 35-64 years were recruited from a general community in Beijing, People's Republic of China. Data were collected with a questionnaire including the basic conditions, menopausal status, and frequency of musculoskeletal symptoms (rarely, occasionally or frequently) during the previous 2 weeks at the neck, lower back, knee and other sites. The prevalences of frequent symptoms were calculated for each site. RESULTS: A total of 743 women were enrolled in the study; 33.4% complained of frequent lower back pain, 31.0% of frequent knee pain, 29.7% of frequent neck pain, 25.6% of joint pain at other sites, 23.6% of joint stiffness and 21.1% of hand joint swelling. Postmenopausal women experienced a significantly higher prevalence of musculoskeletal symptoms compared with premenopausal women. There was a peak in prevalence of musculoskeletal symptoms at early postmenopause. The prevalences of neck pain and lower back pain were not associated with age, but did increase during the perimenopausal stage. The prevalences of knee pain, joint stiffness and hand joint swelling increased significantly with age. Higher body mass index (BMI) was related to increased prevalences of knee pain, joint stiffness and hand joint swelling. Logistic regression analysis showed odds ratios for knee pain, joint stiffness and hand joint swelling of 2.256, 1.865 and 1.955, respectively, in the obese women (BMI ≥ 28 kg/m(2)), compared with women with normal BMI (< 24 kg/m(2)). CONCLUSION: Menopause is known to be a time of increased musculoskeletal symptoms, but the association of musculoskeletal symptoms with age and BMI also should be considered.

Estradiol 1 mg and drospirenone 2 mg as hormone replacement therapy in postmenopausal Chinese women.

OBJECTIVES: Drospirenone is a novel progestogen that, combined with 17ß-estradiol, reduces the frequency and severity of menopausal vasomotor symptoms (VMS) in different populations. This double-blind, multicenter study compared the efficacy, safety and tolerability of 2 mg drospirenone/1 mg estradiol (DRSP/E2) vs. placebo in Chinese postmenopausal women with moderate to severe VMS. METHODS: Women, aged 45-65 years, were randomized to DRSP/E2 (n=183) or placebo (n=61) once daily for four 28-day cycles. Changes in the frequency and severity of hot flushes were analyzed as primary variables, together with other climacteric and urogenital symptoms, clinical global improvement, adverse events and physical/gynecological parameters. RESULTS: Relative changes in numbers of hot flushes/week were -80.4% for DRSP/E2 vs. -51.9% for placebo (treatment difference -28.5%, p<0.0001). There were trends toward a greater reduction in severity of hot flushes with DRSP/E2 treatment. Patients treated with DRSP/E2 were more often free from sweating episodes (p<0.0001) and vaginal dryness (p=0.0008). Other climacteric symptoms, including nervousness and pollakisuria, followed a trend of greater response with DRSP/E2. Similar to other combination HRT regimens, DRSP/E2 increased occurrences of bleeding, but these decreased over time. Adverse events in patients treated with DRSP/E2 were mostly mild to moderate and withdrawal rates were low. CONCLUSIONS: Daily treatment of postmenopausal Chinese women with DRSP/E2 for 16 weeks significantly reduced the incidence of hot flushes and demonstrated advantages vs. placebo for other climacteric symptoms. These results indicate that DRSP/E2 is effective, safe and well tolerated in postmenopausal Chinese women.

Effect of polysaccharides from Ganoderma lucidum on streptozotocin-induced diabetic nephropathy in mice.

The effects of Ganoderma lucidum polysaccharides (GL-PS) on renal complication in streptozotocin-induced diabetic mice have been investigated in the present study. C57BL/6J mice were made diabetic by injection of streptozotocin and GL-PS (125 and 250 mg kg-1) was administered for 8 weeks. Body weight was monitored every week. Serum glucose, creatinine (Cr), blood urea nitrogen (BUN), triglyceride (TG) and urinary albumin excretion (UAE) were measured after 8 weeks of treatment. Glomerular size and mesangial matrix index were assayed by morphometric analysis. Renal expression of transforming growth factor-beta1 (TGF-beta1) were determined by immunochemistry. Renal malondialdehyde (MDA) level and superoxide dismutase (SOD) activities were also evaluated. GL-PS was able to reduce the serum Cr and BUN levels and UAE compared with diabetic model mice in a dose-dependent manner. Increasing serum glucose and triglyceride levels in diabetic mice could also be lowered by GL-PS. Moreover, GL-PS had the capacity to improve the renal morphometric changes and oxidative stress state of diabetic mice. In summary, GL-PS can improve the metabolic abnormalities of diabetic mice and prevent or delay the progression of diabetic renal complications.

Guidelines for hormone replacement therapy of Asian women during the menopausal transition and thereafter.

These Guidelines summarize the position of an Expert Panel on Menopause in Asian Women regarding the use of hormone replacement therapy (HRT) during the menopausal transition and thereafter. They are intended to aid gynecologists, family physicians and other health-care professionals in providing optimal care to menopausal Asian women who desire HRT.

Comparative analyses of multi-species sequences from targeted genomic regions.

The systematic comparison of genomic sequences from different organisms represents a central focus of contemporary genome analysis. Comparative analyses of vertebrate sequences can identify coding and conserved non-coding regions, including regulatory elements, and provide insight into the forces that have rendered modern-day genomes. As a complement to whole-genome sequencing efforts, we are sequencing and comparing targeted genomic regions in multiple, evolutionarily diverse vertebrates. Here we report the generation and analysis of over 12 megabases (Mb) of sequence from 12 species, all derived from the genomic region orthologous to a segment of about 1.8 Mb on human chromosome 7 containing ten genes, including the gene mutated in cystic fibrosis. These sequences show conservation reflecting both functional constraints and the neutral mutational events that shaped this genomic region. In particular, we identify substantial numbers of conserved non-coding segments beyond those previously identified experimentally, most of which are not detectable by pair-wise sequence comparisons alone. Analysis of transposable element insertions highlights the variation in genome dynamics among these species and confirms the placement of rodents as a sister group to the primates.

Comparative physical mapping of targeted regions of the rat genome.

The comparative mapping and sequencing of vertebrate genomes is now a key priority for the Human Genome Project. In addition to finishing the human genome sequence and generating a 'working draft' of the mouse genome sequence, significant attention is rapidly turning to the analysis of other model organisms, such as the laboratory rat (Rattus norvegicus). As a complement to genome-wide mapping and sequencing efforts, it is often important to generate detailed maps and sequence data for specific regions of interest. Using an adaptation of our previously described approach for constructing mouse comparative and physical maps, we have established a general strategy for targeted mapping of the rat genome. Specifically, we constructed a framework comparative map of human Chromosome (Chr) 7 and the orthologous regions of the rat genome, as well as two large (>1-Mb) P1-derived artificial chromosome (PAC)-based physical maps. Generation of these physical maps involved the use of mouse-derived probes that cross-hybridized with rat PAC clones. The first PAC map encompasses the cystic fibrosis transmembrane conductance regulator gene (Cftr), while the second map allows a three-species comparison of a genomic region containing intra- and inter-chromosomal evolutionary rearrangements. The studies reported here further demonstrate that cross-species hybridization between related animals, such as rat and mouse, can be readily used for the targeted construction of clone-based physical maps, thereby accelerating the analysis of biologically interesting regions of vertebrate genomes.

[Features of breast ultrasound image and its correlation with estradiol and progesterone level in different phases of menstrual cycle in normal women].

OBJECTIVE: To determine the features of the breast ultrasound image and its correlation with estrogen and progestogen level during different phases of menstrual cycle in normal women. METHODS: Breast ultrasound was performed during luteal phase and late follicular phase in 50 women aged 25-45, with normal menstrual cycle and no distinct breast disease. Breast section thickness, ductal width, breast structure and blood flow were measured. Initial time and persistent days of the cyclic breast pain were recorded. Serum estradiol (E2) and progesterone (P) levels were measured by enzyme immunoassay on the day of ultrasound performed. RESULTS: Breast glandular section was thicker (increasing by 7.3%) in luteal phase than that in late follicular phase and breast ductal was wider (increasing by 13%) in late follicular phase than that in luteal phase. However, both of them had no significant difference. Thirty women (60%) experienced cyclic premenstrual mastalgia, lasting 4 days. Twenty four women (48%) had breast structure changes, nineteen (63.3%) of 30 women with cyclic mastalgia, but only 5 (25%) of 20 women without breast pain had breast structure change (chi 2, P < 0.01). Average serum E2 level of women with or without cyclic breast pain in luteal phase were 365.0 pmol/L and 335.3 pmol/L respectively (P > 0.05), serum progesterone level were 73.3 nmol/L and 66.1 nmol/L respectively (P > 0.05). Serum E2 levels of women with or without cyclic breast pain in late follicular phase were 299.9 pmol/L and 385.8 pmol/L respectively (P = 0.05). Average serum E2 levels of women with or without breast structure change in luteal phase were 368.1 pmol/L and 322.7 pmol/L respectively (P < 0.05). Serum P levels were 78.8 nmol/L and 62.2 nmol/L respectively (P = 0.05); Estradiol levels in late follicular phase were 301.9 pmol/L and 364.2 pmol/L respectively (P > 0.05). CONCLUSIONS: Image of breast ultrasound changed following menstrual cycle in normal menstrual women. Breast structure changes is related to breast pain. Breast pain and breast structure changes may be caused by higher E2 and P level in luteal phase and lower E2/P ratio in late follicular phase.

[Advances in genetic epidemiology].

We have discussed some advances in genetic epidemiology, which include the effect of gene-environment interaction on diseases. The developing genetic tests and genetic information will benefit the health care and disease prevention.