[Epidemiological analysis of the current prevalence of hepatitis B virus infection among pregnant and postpartum women in China from 2021 to 2023].

Objective: To analyze hepatitis B serologic tests and the current prevalence of hepatitis B virus (HBV) infection among pregnant and postpartum women in China from 2021 to 2023. Methods: Data on managing the prevention of mother-to-child transmission of HIV, syphilis, and hepatitis were retrieved from the National Information System. A positive serum HBsAg test was used to define HBV infection. The χ(2) test was used to compare the coverage rate of the hepatitis B serologic test across different years, in early-stage pregnancy, and the current HBV infection in pregnant and postpartum women. A two-sided P value of <0.05 was considered a statistically significant difference. Results: The coverage rate for hepatitis B serological detection in pregnant (including intrapartum) and postpartum women and early-stage pregnancy rose from 99.68% (10 463 059/10 496 883) and 82.96% (8 707 765/10 496 883) to 99.94% (8 678 777/8 684 387, P < 0.001) and 88.87% (7 717 857/8 684 387, P < 0.001) in China between 2021 and 2023. The current prevalence rate of HBV infection decreased from 4.98% (521 479/10 463 059) in 2021 to 4.56% (396 148/8 678 777) in 2023 among pregnant and postpartum women (P < 0.001). The current prevalence rate of HBV infection ranged from 1.53% to 10.39% among pregnant and postpartum women in various provinces of China in 2023. Conclusion: The coverage rate for hepatitis B serologic tests in China increased significantly between 2021 and 2023 in pregnant and postpartum women. Therefore, the current prevalence rate of HBV infection has decreased significantly in pregnant and postpartum women, but a regional difference still exists.

[Incidence and related factors of antiviral drug resistance in HIV-infected pregnant and postpartum women in some areas of three western provinces of China from 2017 to 2019].

Objective: To analyze the incidence and related factors of drug resistance in HIV-infected pregnant and postpartum women in some areas of three western provinces of China from 2017 to 2019. Methods: From April 2017 to April 2019, face-to-face questionnaires and blood sample testing were conducted in all health care institutions providing maternal and perinatal care and midwifery-assisted services in 7 prevention of mother-to-child transmissi project areas in Xinjiang, Yunnan and Guangxi provinces/autonomous regions. Information was collected during the perinatal period and viral load, CD4+T lymphocytes and drug resistance genes were detected at the same time. The multivariate logistic regression model was used to analyze the relationship between different factors and drug resistance in HIV-infected pregnant and postpartum women. Results: A total of 655 HIV-infected pregnant and postpartum women were included in this study. The incidence of drug resistance was 3.4% (22/655), all of whom were cross-drug resistant. The rate of low, moderate and high drug resistance was 2.1% (14/655), 1.2% (8/655) and 0.8% (5/655), respectively. The drug resistance rate in the people who had previously used antiviral drugs was 1.9% (8/418), and the drug resistance rate in the people who had not used drugs was 5.9% (14/237). The NNRTI drug resistance accounted for 2.8% (18/655) and the NRTI drug resistance rate was 2.5% (16/655). The multivariate logistic regression model showed that the risk of HIV resistance was lower in pregnant women who had previously used antiviral drugs (OR=0.32, 95%CI: 0.11-0.76). Conclusion: Strengthening the management of antiviral drug use and focusing on pregnant and postpartum women who have not previously used antiviral drugs can help reduce the occurrence of drug-resistant mutations. Personalized antiviral therapy should be considered to achieve viral inhibition effects in clinical practice.

[Analysis of the catastrophic health expenditure of HIV-positive maternal households in high AIDS endemic areas in Liangshan prefecture].

Objective: To analysis the income and expenditure of HIV-positive pregnant women and the catastrophic health expenditure of their households in high AIDS endemic areas in Liangshan prefecture. Methods: From December 2018 to January 2019, a total of 250 pregnant women were recruited from 2 of 17 counties in Liangshan Prefecture, including 133 HIV-positive pregnant women and 117 HIV-negative pregnant women. The data, including basic information of pregnant women, basic information of the family, annual family income in 2017, annual family health expenditure in 2017, and maternal and child-related expenditure in 2017, were collected for analyzing the incidence of catastrophic health expenditure in the family. Results: The average annual income and average annual health expenditure of HIV-positive pregnant women households were 7 000 CNY and 2 000 CNY, while those of HIV-negative pregnant women households were 10 000 CNY and 3 000 CNY, respectively. Based on the criteria of 15%, 25% and 40%, the incidence of catastrophic health expenditure of HIV-positive pregnant households was 39.10%, 33.83% and 27.82%, with average differences of 34.84%, 31.17% and 26.65%, respectively, while that of HIV-negative pregnant women households was 38.46%, 33.33% and 23.93%, with average differences of 31.68%, 28.35% and 24.22%, respectively. Conclusion: The incidence of catastrophic health expenditure of pregnant households in high AIDS endemic areas in Liangshan prefecture is high. The incidence of HIV-positive families is slightly higher than that of HIV-negative families. We suggest that medical insurance compensation in Liangshan prefecture should be improved to reduce the impact of catastrophic health expenditure.

Suppression of αvß6 downregulates P-glycoprotein and sensitizes multidrug-resistant breast cancer cells to anticancer drugs.

Multidrug resistance (MDR) in breast cancer treatment is the major cause leading to the failure of chemotherapy. P-glycoprotein (P-gp), the product of the human MDR1 gene, plays a key role in resistance to chemotherapy and confers cross-resistance to many structurally unrelated anticancer drugs. We have previously reported that integrin αvß6 plays a critical role in breast cancer invasion and metastasis. However, whether and how αvß6 is associated with P-gp and regulated by potential genetic mechanisms in breast cancer remains unclear. In the present study, we further investigated the reversal effect and underlying mechanisms of MDR in breast cancer. Two small interfering RNA constructs (pSUPER-ß6shRNAs) targeting two different regions of the ß6 gene have been designed to inhibit αvß6 expression by transfecting them into adriamycin-resistant MCF-7/ADR cell lines. Suppression of αvß6 dramatically downregulated the levels of MDR1 gene mRNA and P-gp. In particular, ß6shRNA-mediated silencing of αvß6 gene increased significantly the cellular accumulation of Rhodamine 123 and markedly decreased drug efflux ability, suggesting that ß6shRNAs indeed inhibit P-gp mediated drug efflux and effectively overcome drug resistance. In addition, inhibition of integrin αvß6 suppressed the expression of ERK1/2. Interestingly, our data demonstrate that suppression of integrin αvß6 caused significant downregulation of Bcl-2, Bcl-xL and upregulation of caspase 3, Bad, accompanied by increasing activity of cytochrome C. A possible connection between αvß6 and P-gp in drug resistance biology is suggested. Taken together, ß6shRNA could efficiently inhibit αvß6 and MDR1 expression in vitro and these findings may offer specifically useful means to reverse MDR in breast cancer therapy.

[Epidemic trend of COVID-19 in Chinese mainland].

Objective: In order to understand the epidemic trend of COVID-19 and evaluate the effect of prevention and control, this study aims to evaluate the epidemic dynamics of COVID-19 in Chinese mainland from January 16 to February 14, 2020. Methods: The daily number of new confirmed COVID-19 cases detected by nucleic acid was collected from the National Health Commission from January 16, 2020 to February 14, 2020. The analysis included the epidemic curve of the new confirmed cases, multiple of the new confirmed cases for period-over-period, multiple of the new confirmed cases for fixed-base, and the period-over-period growth rate of the new confirmed cases. Results: From January 16 to February 14, 2020, the cumulative number of new confirmed cases of COVID-19 in Chinese mainland was 50 031, including 37 930 in Hubei Province, 22 883 in Wuhan city and 12 101 in other provinces outside Hubei. The peak of new confirmed cases in other provinces outside Hubei was from January 31 to February 4, 2020, and the peak of new confirmed cases in Wuhan city and Hubei Province was from February 5 to February 9, 2020. The number of new confirmed cases in other provinces outside Hubei showed a significant decline (23% compared with the peak) from February 5 to February 9, 2020, while the number of new confirmed cases in Wuhan city (30% compared with the peak) and Hubei Province (37% compared with the peak) decreased significantly from February 10 to February 14, 2020. Conclusion: The epidemic prevention and control measures taken by the state and governments at all levels have effectively curbed the spread of the COVID-19 epidemic in Chinese mainland.

Laser Cooling of Radium Ions.

The unstable radium nucleus is appealing for probing new physics due to its high mass, octupole deformation, and energy level structure. Ion traps, with long hold times and low particle numbers, are excellent for work with radioactive species, such as radium and radium-based molecular ions, where low activity, and hence low total numbers, is desirable. We address the challenges associated with the lack of stable isotopes in a tabletop experiment with a low-activity (∼10 µCi) source where we laser-cool trapped radium ions. With a laser-cooled radium ion we measured the 7p^{2}P_{1/2}^{o} state's branching fractions to the ground state, 7s^{2}S_{1/2}, and a metastable excited state, 6d^{2}D_{3/2}, to be p=0.9104(7) and 0.0896(7), respectively. With a nearby tellurium reference line we measured the 7s^{2}S_{1/2}→7p^{2}P_{1/2}^{o} transition frequency, 640.096 63(6) THz.

[Serologic surveillance indicators analysis among syphilis-infected pregnant women in East China].

Objective: To analyze serologic surveillance indicators during pregnancy among syphilis-infected women who delivered in 2013 in East China. Methods: Data were from national 'Information System of Prevention of Mother-to-child Transmission of HIV, syphilis and HBV Management' and in total 5 206 syphilis-infected pregnant women who delivered in 2013 and in East China were involved in the analysis. Information on demographic characters, laboratory tests, and treatment regimens were collected. The maternal non-treponemal testing surveillance and titer distribution were described and compare the proportions between pregnant women receiving standard testing and non-standard testing, taking baseline testing and testing before delivery or at the third trimester. Multivariate logistic regression model was analyzed using maternal titer control as dependent variable, using prior history of syphilis infection, syphilis stages, titer, gestational weeks of treatment initiation and treatment regimens as independent variables in 3 940 pregnant women with both baseline testing results and testing results before delivery or at the third trimester. Results: The ages of the 5 206 syphilis infected pregnant women were (28.1±5.8) years old. The numbers of women received penicillin treatment, other treatment regimens and no treatment were 2 967 (57.0%), 281 (5.4%), and 1 958 (37.6%), respectively. The number of women with maternal seroconversion, 4-fold or greater titer decline, or titer increase were 349 (6.7%), 251 (4.8%) and 28 (0.5%). Multivariate analysis results showed that compared with pregnant women with prior history of syphilis, the OR(95%CI) for maternal titer control was 1.49 (1.18-1.88) among those with syphilis-infection history. Compared with pregnant women initiated treatment at 28 gestational weeks or before, the OR (95%CI) for maternal titer control was 4.09 (3.19-5.24) among those who initiated treatment after 28 gestational weeks. Compared with pregnant women initiated treatment at 28 gestational weeks or before, the OR (95%CI) for maternal titer control was 4.09 (3.19-5.24) among those who initiated treatment after 28 gestational weeks or received no treatment. Compared with pregnant women received penicillin treatment, the OR (95%CI) for maternal titer control among those received non-penicillin treatment and those received no treatment were 2.35 (1.46-3.76) and 1.55 (1.13-2.12), respectively. Conclusion: In East China, the proportion of women achieved seroconversion or 4-fold or greater titer decline during pregnancy was very low. Pregnant women with no prior history of syphilis infection, early maternal initiation of treatment, and penicillin treatment were more likely to reach maternal titer control.

Association between killer cell immunoglobulin-like receptor 2DS5 gene with essential hypertension in the Chinese Han patients.

Hypertension has been suggested to be mediated by immunity and inflammation. As immune system genes, killer cell immunoglobulin-like receptors (KIRs) genes play an important role in the pathogenesis of autoimmune diseases. We conducted a community population-based case-control study to analyse associations between KIR genes and hypertension. KIR genes were genotyped using sequence-specific primer polymerase chain reaction in 380 unrelated essential hypertensives and 527 normotensives. The frequencies of KIR2DS5 gene were significantly decreased in participants with high high-sensitivity C-reactive protein (hsCRP) compared with participants with low hsCRP (17.02% vs 34.08%, p = .016). The presence of KIR2DS5 gene was independently associated with decreased risk of hypertension (odds ratio = 0.62; 95% confidence interval: 0.43-0.89), after adjusted for conventional risk factors, hsCRP and other KIR genes. We found that participants with KIR2DS5 gene had a decreased risk of hypertension compared with participants without KIR2DS5 gene. Our findings suggested that KIR2DS5 gene may be protective against hypertension.

Ineffectiveness of the Tobacco Hazards Prevention Act in patients with severe and persistent mental illness.

OBJECTIVES: The effect of the Tobacco Hazards Prevention Act (THPA) on the reduction of tobacco use in the general population in Taiwan is understood. However, there has been little research on how these policies affect people with severe and persistent mental illness (SPMI). Hence, the influence of the THPA on daily cigarette use by patients with SPMI was investigated in a 3-year follow-up. The risk and protective factors in smoking behavior and cessation were investigated. STUDY DESIGN: This is an observational study. METHODS: A total of 144 participants (78 of whom had smoked >100 cigarettes throughout their lifetime) were randomly selected from a healthcare network. Then, 100 of 144 patients with SPMI, included 50 smokers and 50 non-smokers, have agreed with 1st year follow-up. Eighty-two patients with SPMI, consisted of 44 smokers and 38 non-smokers, have agreed with 2nd year follow-up. RESULTS: Although women were less likely to smoke than men, those who did smoke reduced the number of cigarettes less than men over the 3-year period. Less-educated patients were more likely to smoke than those who were more educated but reduced the number of daily cigarettes more after implementation of the THPA. Maternal overprotection was a risk factor and paternal care a protective factor for smoking. Addiction, a perception of pleasure, interpersonal relationships, and self-destructive behavior increased cigarette smoking. Patients perceived that smoking alleviated their depressive symptoms. CONCLUSIONS: The THPA was ineffective for patients with SPMI. Some factors had different effects on the development of smoking behavior and the cessation process. Understanding the etiology of smoking can help policymakers establish more effective programs for smoking prevention and cessation.

[Comprehensive review of factors and preventions of mother to child transmission of hepatitis B virus].

Mother-to-child transmission of hepatitis B virus (HBV) is one of major public health issues. Difference is found on effect of preventions of mother to child transmission of HBV such as Hepatitis B vaccine, Hepatitis B immunoglobulin and antiretroviral drugs. Based on the risks of hepatitis B virus on children, influencing factors and interventions of HBV mother-to-child transmission were explored to improve prevention mother-to-child transmission of hepatitis B and to search appropriate strategies reducing mother-to-child transmission of HBV.

Association between matrix metalloproteinase-9 rs3918242 polymorphism and development of coronary artery disease in a Chinese population.

We conducted a case-control study to investigate the role of one single nucleotide polymorphism of MMP-9 rs3918242 in the development of coronary artery disease. The rs3918242 was amplified with 435-bp DNA fragments using polymerase chain reaction coupled with restriction fragment length polymorphism. When compared with control subjects, patients with coronary artery disease had higher systolic and diastolic blood pressure, as well as higher triglycerides (P < 0.05), were more likely to suffer from diabetes mellitus, and had lower total cholesterol and high-density lipopolysaccharides. Using unconditional logistic analysis, we found that individuals with CT and TT genotypes were associated with increased risk of coronary artery disease in a co-dominant model, and the ORs (95%CI) were 1.50 (1.02-2.20) and 6.89 (2.51-23.41) for CT and TT, respectively. We observed that the T allele of rs3918242 was correlated with increased risk of coronary artery disease (OR = 1.88, 95%CI = 1.39-2.55). In conclusion, we suggest that the TT and CT genotypes and T allele of MMP-9 rs3918242 polymorphism is correlated with an increased risk of coronary artery disease in a Chinese population.

[Mode of delivery among HIV-positive pregnant women in areas with high prevalence of HIV in China, 2007-2013].

OBJECTIVE: To describe the changing demographic profile over time of pregnant women diagnosed with HIV infection, and trends in mode of delivery and pregnancy outcome. METHODS: An observational investigation was conducted based on a population of 1 128 HIV-positive pregnant women at eight sites in China in provinces with high prevalence of HIV among pregnant women and children between 2007 and 2013. The study area included Shangcai and Weishi counties in Henan province; Ruili and Longchuan counties and Linxiang prefecture in Yunnan province; Yining County in Xinjiang; and Lingshan county and Babu district in Guangxi province. Main outcome measures were maternal characteristics, mode of delivery, and related trends over time by Cochram-Mantel-Haenszel(CMH) χ(2)-test. RESULTS: A total hospital delivery rate of 96.4% was reported. For each year during the period 2007-2013, hospital delivery rates were 95.1% (253/266), 94.8% (188/198), 93.7% (164/175), 98.8% (159/161), 98.6% (141/143), 97.4% (114/117), and 100.0% (68/68), respectively (χ(2)CMH=7.68, P=0.006). The neonatal survival rate increased by 0.7% incrementally from 2007 to 2013, with 98.5% (262/266), 99.0% (196/198), 99.4% (174/175), 99.4% (160/161), 100.0% (143/143), 100.0% (117/117), and 100.0% (68/68), respectively (χ(2)CMH=4.58, P=0.030). The proportions of vaginal deliveries in those years were 62.2% (166/266), 54.8% (109/198), 59.9% (105/175), 61.7% (100/161), 66.7% (96/143), 58.8% (69/117), and 66.7% (46/68), respectively (χ(2)CMH=1.19, P= 0.276). The average rate for midwives skilled in procedures such as artificial rupture of membranes and episiotomy was 37.8% (261/691), with proportions decreasing during the study period at 39.2% (65/166), 47.4% (52/109), 35.9% (38/105), 46.0% (46/100), 25.5% (25/96), 31.2% (22/69), and 28.3% (13/46), respectively (χ(2CMH)=6.76, P=0.009). CONCLUSION: The annual rate of reported hospital delivery increased between 2007 and 2013, with a declining rate of skilled midwifery over the same period. Survival of neonates born to HIV-infected mothers in China has increased to nearly equivalent levels as those of developed countries.

Dopamine in the nucleus accumbens core, but not shell, increases during signaled food reward and decreases during delayed extinction.

UNLABELLED: Microdialysis studies in rat have generally shown that appetitive stimuli release dopamine (DA) in the nucleus accumbens (NAc) shell and core. Here we examined the release of DA in the NAc during delivery of reward (food) and during extinction of food reward in the freely moving animal by use of in vivo microdialysis and HPLC. Fifty-two male Wistar rats were trained to receive food reward associated with appearance of cue-lights in a Skinner-box during in vivo microdialysis. Different behavioral protocols were used to assess the effects of extinction on DA and its metabolites. Results Exp. 1: (a) During a 20-min period of cued reward delivery, DA increased significantly in the NAc core, but not shell subregion; (b) for the next 60min period half of the rats underwent immediate extinction (with the CS light presented during non-reward) and the other half did not undergo extinction to the cue lights (CS was not presented during non-reward). DA remained significantly increased in both groups, providing no evidence for a decrease in DA during extinction in either NAc core or shell regions. (c) In half of the animals of the group that was not subjected to extinction, the cue lights were turned on for 30min, thus, initiating extinction to cue CS at a 1h delay from the period of reward. In this group DA in the NAc core, but not shell, significantly decreased. Behavioral analysis showed that while grooming is an indicator of extinction-induced behavior, glances toward the cue-lights (sign tracking) are an index of resistance to extinction. Results Exp. 2: (a) As in Exp. 1, during a 30-min period of cued reward delivery, DA levels again increased significantly in the NAc core but not in the NAc shell. (b) When extinction (the absence of reward with the cue lights presented) was administered 24h after the last reward session, DA again significantly decreased in the NAc core, but not in the NAc shell. CONCLUSIONS: (a) These results confirm the importance of DA release in the NAc for reward-related states, with DA increasing in the core, but not shell subregion. (b) They provide first evidence that during the withholding of expected reward, DA decreases in the NAc core, but not shell region. (c) This decrease in DA appears only after a delay between delivery of reward and extinction likely due to it being masked by persisting DA release. We hypothesize the decrease in extinction-induced release of DA in the NAc core to be a marker for the despair/depression that is known to accompany the failure to obtain expected rewards/reinforcers.

Association between a functional single nucleotide polymorphism in the brain-derived neurotrophic factor gene and risk of child asthma.

Brain-derived neurotrophic factor (BDNF) promotes synaptic remodeling and modulates the function of other neurotransmitters. Allergic inflammation triggers neuronal dysfunction and structural changes in the airways. Genetic polymorphisms in functional regions of the BDNF gene have a plausible role in modulating the risk of child asthma (CA). This study examined the potential association between CA and three single nucleotide polymorphisms (SNPs) in BDNF (rs2030323, rs6265, and rs16917204 in the promoter, exon 4, and 3'-untranslated regions, respectively). The study was conducted in 350 children with asthma and 356 healthy controls. The genotype and allele frequencies and difference between groups were analyzed using HaploView 4.0 and SPSS 20.0 software platforms. The analysis revealed a strong association between the rs6265 genotype distribution and CA. The frequency of the G allele was significantly higher in CA patients than in healthy controls (P = 0.0007, odds ratio = 1.323, 95% confidence interval = 1.073-1.632). Strong linkage disequilibrium was observed between rs16917204 and rs6265. A significantly higher number of G-G haplotypes were observed in CA patients than in controls (P = 0.024 after Bonferroni correction), while the G-A haplotypes were more significant in controls (P = 0.013 after Bonferroni correction). This suggested that BDNF gene polymorphisms confer susceptibility to CA, and also support the notion that BDNF dysfunction is involved in the pathophysiological process of CA.

Neurobehavioural analysis of developmental iron deficiency in Oreochromis aureus × Oreochromis niloticus.

The objective of this study was to examine the association between brain iron measurements of monoamine function and behavioural measurements of learning and memory. Male hybrid tilapias Oreochromis aureus × Oreochromis niloticus were fed either an iron-deficient (ID) diet or an iron-adequate (IA) diet for 8 weeks. The ID fishes showed significantly lower iron content in brain and decreasing learning and memory capacity. The fishes that showed increased learning and memory capacity had higher levels of iron and monoamine oxidase activity in brain. In addition, the results showed that learning and memory behaviours were related to monoamine (dopamine and noradrenaline) concentration in the brain. This suggests that iron can enhance learning and memory capacity in fishes and that the effect may have monoaminergic mediation in discrimination learning and memory tasks. The experimental data suggest that the properties and neural basis of learning and memory of teleosts are notably similar to those of land vertebrates.

[Analysis of loss to follow-up status and influencing factors of children born to pregnant women with HIV infection in China in 2019].

Objective: To understand the loss to follow-up of children born to pregnant women with HIV infection (HIV-exposed children) and analyze its influencing factors in China in 2019. Methods: The data were collected from the follow-up records of pregnant women with HIV infection and their children reported by the national "Management Information System for the Prevention of HIV, syphilis and Hepatitis B Mother-to-Child Transmission" in 2019. HIV-exposed children were defined as those who were not followed up after birth or who were not followed up at 18 months of age and who were not followed up at 21 months of age. The univariate and multivariate influencing factors of loss to follow-up of children born to HIV-infected pregnant women were analyzed by χ2 test and logistic regression model. SPSS 25.0 software was used for statistical analysis. Results: The number of HIV-infected pregnant women was 5 039, the number of live-born children was 5 035, the number of loss to follow-up children within 18 months of age was 283, and the loss to follow-up rate children was 5.62%(283/5 035). The results of multivariate logistic regression analysis showed that the rate of loss to follow-up of exposed children born to pregnant women who worked as farmers (animal husbandry and fishery) (aOR=0.34, 95%CI: 0.22-0.53), unmarried (aOR=0.47, 95%CI: 0.24-0.93), first marriage (aOR=0.38, 95%CI: 0.22-0.67), remarriage (aOR=0.36, 95%CI: 0.20-0.67) and cohabiting (aOR=0.47, 95%CI: 0.23-0.97), and knew they had HIV infection before this pregnancy (aOR=0.53, 95%CI: 0.40-0.70) was lower. Han nationality (aOR=1.52, 95%CI: 1.09-2.13), primary school (aOR=2.06, 95%CI: 1.10-3.89) and junior middle school (aOR=1.81, 95%CI: 1.03-3.17) educational level, non-use of antiviral drugs (aOR=6.21, 95%CI: 4.32-8.93) and delivery in township (street) level midwifery institutions (aOR=5.72, 95%CI: 1.61-20.27) had higher rates of loss to follow-up among infants born to HIV-infected pregnant women. Conclusions: HIV-exposed children still have a specific rate of loss to follow-up in China in 2019. In order to further reduce the rate of loss to follow-up, it is of great significance to improve the detection rate of HIV before pregnancy and the rate of antiviral drugs used in pregnant women with HIV infection, which is of great significance for the effective implementation of comprehensive intervention measures of prevention of mother-to-child transmission of HIV.

Jet or intensive care unit ventilator during simulated percutaneous transtracheal ventilation: a lung model study.

BACKGROUND: Percutaneous transtracheal ventilation (PTV) via a jet ventilator (PTJV) is considered a rescue technique in difficult airway management. However, whether a conventional ventilator can generate adequate ventilation via PTV is not known. Our goal was to evaluate the tidal volume (V(T)) generated by a conventional ventilator during simulated PTV compared with PTJV in a lung model. METHODS: A lung model simulating an adult lung was used. A catheter was inserted through the artificial trachea and connected to either a jet ventilator or a conventional ventilator. The direction of catheter insertion was perpendicular to the trachea, pointing towards the lung and away from the lung. The jet ventilator was operated at 344.7 kPa. The conventional ventilator was operated in the pressure mode at peak inspiratory pressures of 40-90 cm H(2)O. RESULTS: The jet ventilator generated larger V(T) [817 (336) ml] when the catheter was pointing towards the lung than when pointing away from the lung or perpendicular to the trachea [121 (41) and 69 (24) ml, respectively, P<0.01]. With the conventional ventilator, changes in V(T) at different direction of catheter insertion were much less [222 (81) ml catheter pointing towards the lung, 229 (121) ml perpendicular to the trachea, and 187 (97) ml away from the lung]. CONCLUSIONS: Our result demonstrated that PTJV was effective only when the catheter was pointing towards the lung and requires high operating pressure. A conventional ventilator can generate reasonable minute ventilation through the transtracheal catheter less dependent on directions of catheter insertion and should be considered during emergent PTV.

Neuropeptide Y in black seabream Acanthopagrus schlegelii: identification, distribution and mRNA expression responses to ghrelin.

The coding region of neuropeptide Y (NPY) complementary (c)DNA was cloned from the hypothalamus RNA of black seabream Acanthopagrus schlegelii, including 297 bp coding for prepro-NPY of 98 amino acids. Real-time reverse transcriptase-polymerase chain reaction was performed to determine A. schlegelii npy gene expression; NPY messenger RNA (mRNA) was expressed highly in the brain and stomach. Treatment with acylated ghrelin significantly up-regulated NPY mRNA level in the hypothalamus, suggesting that NPY may be involved in regulating food intake of A. schlegelii.

Stimulus novelty, and not neural refractoriness, explains the repetition suppression of laser-evoked potentials.

Brief radiant laser pulses selectively activate skin nociceptors and elicit transient brain responses (laser-evoked potentials [LEPs]). When LEPs are elicited by pairs of stimuli (S1-S2) delivered at different interstimulus intervals (ISIs), the S2-LEP is strongly reduced at short ISIs (250 ms) and progressively recovers at longer ISIs (2,000 ms). This finding has been interpreted in terms of order of arrival of nociceptive volleys and refractoriness of neural generators of LEPs. However, an alternative explanation is the modulation of another experimental factor: the novelty of the eliciting stimulus. To test this alternative hypothesis, we recorded LEPs elicited by pairs of nociceptive stimuli delivered at four ISIs (250, 500, 1,000, 2,000 ms), using two different conditions. In the constant condition, the ISI was identical across the trials of each block, whereas in the variable condition, the ISI was varied randomly across trials and single-stimulus trials were intermixed with paired trials. Therefore the time of occurrence of S2 was both less novel and more predictable in the constant than in the variable condition. In the constant condition, we observed a significant ISI-dependent suppression of the biphasic negative-positive wave (N2-P2) complex of the S2-LEP. In contrast, in the variable condition, the S2-LEP was completely unaffected by stimulus repetition. The pain ratings elicited by S2 were not different in the two conditions. These results indicate that the repetition-suppression of the S2-LEP is not due to refractoriness in nociceptive afferent pathways, but to a modulation of novelty and/or temporal predictability of the eliciting stimulus. This provides further support to the notion that stimulus saliency constitutes a crucial determinant of LEP magnitude and that a significant fraction of the brain activity time-locked to a brief and transient sensory stimulus is not directly related to the quality and the intensity of the corresponding sensation, but to bottom-up attentional processes.

Quantitative investigations of idiotypic antibodies. VI. Idiotypic specificity as a potential genetic marker for the variable regions of mouse immunoglobulin polypeptide chains.

Antisera were prepared in rabbits against anti-p-azobenzoate antibodies of an A/J and a BALB/c mouse and anti-p-azophenylarsonate antibodies of an A/J mouse. After appropriate absorption the antisera reacted with the anti-hapten antibody of the donor mouse but, by sensitive quantitative tests, not at all with other components of the hyperimmune serum or with preimmune serum of the donor mouse. The absorbed antiserum therefore appeared to be specific for idiotypic determinants. Nearly all idiotypic specificities identified in the serum of the donor were also present in the serum of other mice of the same strain, immunized against the same hapten group, but not in mice immunized with a different hapten. In each case the antibodies of the donor mouse reacted most effectively on a weight basis with antiidiotypic antiserum. Cross-reactions were observed among different strains of mice but homologous anti-bodies reacted most effectively with antiidiotypic antisera. C57/BL and DBA antisera contained very low concentrations of specificities present in the A/J and BALB/c antibody populations; antibodies of A/J and BALB/c antisera are more closely related to one another. The results indicate that idiotypic specificity may provide a genetic marker for the variable regions of immunoglobulin polypeptide chains.