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1.

Background

BCG vaccination is administered in infancy in most countries with the aim of providing protection against tuberculosis. There is increasing interest in the role of vitamin D in immunity to tuberculosis. This study objective was to determine if there was an association between circulating 25(OH)D concentrations and BCG vaccination status and cytokine responses following BCG vaccination in infants.

Methods

Blood samples were collected from UK infants who were vaccinated with BCG at 3 (n = 47) and 12 (n = 37) months post BCG vaccination. These two time-points are denoted as time-point 1 and time-point 2. Two blood samples were also collected from age-matched unvaccinated infants (n = 32 and 28 respectively), as a control group. Plasma vitamin D concentrations (25(OH)D) were measured by radio-immunoassay. The cytokine IFNγ was measured in supernatants from diluted whole blood stimulated with M.tuberculosis (M.tb) PPD for 6 days.

Results

58% of infants had some level of hypovitaminosis (25(OH)D <30ng/ml) at time-point 1, and this increased to 97% 9 months later. BCG vaccinated infants were almost 6 times (CI: 1.8–18.6) more likely to have sufficient vitamin D concentrations than unvaccinated infants at time-point 1, and the association remained strong after controlling for season of blood collection, ethnic group and sex. Among vaccinees, there was also a strong inverse association between IFNγ response to M.tb PPD and vitamin D concentration, with infants with higher vitamin D concentrations having lower IFNγ responses.

Conclusions

Vitamin D may play an immuno-regulatory role following BCG vaccination. The increased vitamin D concentrations in BCG vaccinated infants could have important implications: vitamin D may play a role in immunity induced by BCG vaccination and may contribute to non-specific effects observed following BCG vaccination.  相似文献   

2.
The immaturity of the immune system increases the susceptibility of young infants to infectious diseases and prevents the induction of protective immune responses by vaccines. We previously reported that Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccination induces a potent Th1 response to mycobacterial Ags in newborns. In this study, we evaluated the influence of BCG on the response to unrelated vaccines given in early life. Newborns were randomly allocated to one of three study groups receiving BCG at birth, when infants received their first dose of hepatitis B and oral polio vaccines; at 2 mo of age, when infants received their first dose of diphtheria and tetanus vaccines; or at 4.5 mo of age, when immune responses to vaccines were measured. Administration of BCG at the time of priming markedly increased the cellular and Ab responses to the hepatitis B vaccine, but had only a limited influence on the cytokine response to tetanus toxoid and no effect on the Ab responses to tetanus and diphtheria toxoids. Although BCG induced a potent Th1-type response to mycobacterial Ags, it promoted the production of both Th1- and Th2-type cytokines in response to unrelated vaccines. The effect of BCG was apparent at the systemic level, as it increased the Ab response to oral polio vaccine. These results demonstrate that BCG influences the immune response to unrelated Ags in early life, likely through its influence on the maturation of dendritic cells.  相似文献   

3.
To gain further insight into the problem of infant sudden death, a study was undertaken to investigate a complete series of cases of infant sudden unexplained death that occurred during a seven-year period in Sacramento County. Needed information was abstracted from autopsy records, Medical Examiner''s records and death certificates. The average death rate for the seven-year period was 1.7 for 1,000 live births. Average age at time of death was 2.8 months. There were no records of sudden death among infants over the age of eight months.Higher than average death rates were observed within many of the low socioeconomic areas of Sacramento County. Also, sudden unexplained deaths appeared to occur more frequently in the winter months than in the spring, summer or fall. In over half the cases the infants had a cold, the sniffles, or other respiratory tract congestion within two weeks of the date of death, which seems to support the oft-quoted contention concerning the possibility of nasal obstruction which could initiate the fatal apnea. An additional notable finding was the very frequent occurrence of petechial hemorrhage in the thymus, heart, and lung tissues.The unique age distribution of these deaths in combination with the high frequency of low socioeconomic groups and the frequency of minor respiratory ailment would suggest approaches that can be taken to identify infants at high risk and thus initiate effective community health programs for prevention.  相似文献   

4.
A total of 199 patients with stage I malignant melanoma at Clark''s level 3 to 5 of invasion were entered into a prospectively controlled randomized clinical trial that attempted to assess the value of local and systemic immunotherapy with BCG (bacille Calmette-Guérin) after surgery. The patients were randomly assigned, with stratification by Clark''s level, to receive either routine follow-up or immunotherapy with BCG, administered intradermally with a Heaf gun around the site of wide excision and then given orally for 2 years. Intradermal administration of BCG was repeated after 1 year''s oral therapy with BCG. Of the 99 patients in the treatment group 66 had Clark''s level 3, 28 had level 4, and 5 had level 5 invasion. Of the 100 patients in the control group, 61 had level 3, 36 had level 4, and 3 had level 5 invasion. Other prognostic factors, such as sex, depth of invasion, histologic features, site of disease and type of surgery, were evenly distributed. There were 57 recurrences of the melanoma, 24 in the treatment group and 33 in the control group. However, this trend was not statistically significant (p = 0.194). The suggestion that BCG may reduce the likelihood of local/regional recurrence has not been confirmed with longer follow-up. There were 13 such recurrences in the BCG group, compared with 21 in the control group; the proportions of patients in each group who had such a recurrence were not significantly different. Of the 199 patients 41 died, 24 in the control group and 17 in the treatment group; again, this difference was not significant. While there may be minor activity in selected patients, there appeared to be no benefit from this form of adjuvant BCG therapy in patients with malignant melanoma.  相似文献   

5.
Viruses were shown to be present in the respiratory tract in 200 of 763 cases of the sudden infant death syndrome studied in the nine years 1974-82. Epidemiological and pathological evidence suggested that the distribution of viruses in the sudden infant death syndrome differs between infants aged 3 months or less and those aged over 3 months: the incidence of detection of virus was 14% in the younger group compared with 39% in the older group. The distribution of the viruses in these two groups was compared with that in 1341 live infants with respiratory virus infections. Adenovirus, influenza virus, parainfluenza virus, and rhinovirus had similar distribution among the victims of the sudden infant death syndrome and live controls. The incidence of detection of respiratory syncytial virus was increased in the older infants dying of the sudden infant death syndrome (90% of the cases detected) compared with the older group of live infants (53%). Antibody studies, detection of virus, and epidemiological data suggest that respiratory syncytial virus may be a precipitating factor of sudden death in older infants.  相似文献   

6.
The common bacterial toxins hypothesis of sudden infant death syndrome (SIDS) is that nasopharyngeal bacterial toxins can trigger events leading to death in infants with absent/low levels of antibody that can neutralise the toxins. The aim of this study was to investigate nasopharyngeal carriage of Staphylococcus aureus and determine levels of immunity in the first year of life to toxic shock syndrome toxin (TSST-1) and staphylococcal enterotoxin C (SEC). Both toxins have been implicated in SIDS cases. Seventy-three mothers and their infants (39 males and 34 females) were enrolled onto the study. The infants had birth dates spread evenly throughout the year. In infants, S. aureus carriage decreased significantly with age (P<0.001). Between 40% and 50% of infants were colonised with S. aureus in the first three months of life and 49% of the isolates produced one or both of the staphylococcal toxins. There was a significant correlation between nasopharyngeal carriage of S. aureus in mothers and infants in the three months following the birth (P<0.001). Carriage of S. aureus in infants and their mothers was not significantly associated with levels of antibody to TSST-1 or SEC in cord blood, adult saliva or breast milk. Infants colonised by S. aureus had higher levels of salivary IgA to TSST-1 than infants who were culture negative. Analysis of cord blood samples by a quantitative ELISA detected IgG bound to TSST-1 and SEC in 95.5% and 91.8% of cases respectively. There was a marked variation in levels of maternal IgG to both TSST-1 and SEC among cord blood samples. Maternal age, birth weight, and seasonality significantly affected the levels of IgG binding to TSST-1 or SEC. Analysis of infant saliva samples detected IgA to TSST-1 and SEC in the first month after birth; 11% of samples tested positive for salivary IgA to TSST-1 and 5% for salivary IgA to SEC. By the age of two months these proportions had increased to 36% and 33% respectively. More infants who used a dummy tested positive for salivary IgA to TSST-1 compared to infants who did not use a dummy. Levels of IgA to TSST-1 and SEC detected in the breast-milk samples varied greatly among mothers. There was a trend for infants receiving breast milk with low levels of antibody to TSST-1 or SEC to have higher levels of salivary antibody to the toxins. In conclusion, passive immunity to toxins implicated in SIDS cases varies greatly among infants. Infants are able to mount an active mucosal immune response to TSST-1 and SEC in the first month of life.  相似文献   

7.
The reported numbers of Covid-19 cases and deaths were compared for 18 countries (14 in Western Europe, plus Australia, Brazil, Israel and the USA) to assess the effect of historic and current national BCG immunizations. In view of the high death rate for Covid-19 patients over 70 years of age, and given the fact that BCG vaccination is typically given early in life, we compared countries that had introduced BCG in the 1950s with those that had not. No effect on Covid-19 case fatality rate (CFR) or number of deaths per population could be demonstrated. Since some countries test for Covid-19 more than others, the effect of tests performed per million population on reported deaths per million was also assessed, but again did not demonstrate an effect of BCG vaccination in the 1950s. Whether countries had never used the vaccine, had historically used it but since ceased to do so, or were presently vaccinating with BCG did not correlate with national total number of deaths or CFR. We conclude that there is currently no evidence for a beneficial effect of BCG vaccination on Covid-19 reported cases or fatalities.  相似文献   

8.
mpt64-卡介苗重组疫苗的构建、免疫原性及抗结核作用   总被引:1,自引:0,他引:1  
通过基因工程重组技术将结核分枝杆菌保护性抗原MPT64的编码基因与穿梭质粒载体pYUB295重组,采用电穿孔技术将重组质粒导入到卡介苗中,应用聚合酶链反应(PCR)扩增、聚丙烯酰胺凝胶电泳(PAGE)对mpt64-卡介苗重组疫苗鉴定:成功地构建了MPT64基因pYUB295重组质粒,MPT64蛋白在卡介苗中能分泌表达....  相似文献   

9.
OBJECTIVE--To compare the thermal environment of infants who died of the sudden infant death syndrome with that of age matched control infants. DESIGN--Case-control study. Infants who died were matched with two controls, one for age and one for age and birth weight. Thermal measurements were conducted at the death scene for cases and at the scene of last sleep for control infants, who were visited unexpectedly within four weeks of the index infant''s death on a day of similar climatic conditions. A follow up questionnaire was administered to parents of cases and controls. SETTING--The geographical area served by the professional Tasmanian state ambulance service, which includes 94% of the Tasmanian population. SUBJECTS--41 infants died of the sudden infant death syndrome at home; thermal observations at death scene were available for 28 (68%), parental questionnaire data were available for 40 (96%). 38 controls matched for age and 41 matched for age and birth weight. RESULTS--Cases had more excess thermal insulation for their given room temperature (2.3 togs) than matched controls (0.6 togs) (p = 0.009). For every excess thermal insulation unit (tog) the relative risk of the sudden infant death syndrome was 1.26 (95% confidence interval 1.05 to 1.52). The average thermal bedding value calculated from parental recall was similar to that observed by attendant ambulance officers (mean difference = 0.4 tog, p = 0.39). Cases were more likely to have been found prone (odds ratio 4.58; 1.48 to 14.11). Prone sleeping position was not a confounder or effect modifier of the relation between excess thermal insulation and the syndrome. CONCLUSIONS--Overheating and the prone sleeping position are independently associated with an increased risk of the sudden infant death syndrome. Further work on infant thermal balance and sudden infant death is required and guidelines for appropriate infant thermal care need to be developed.  相似文献   

10.
OBJECTIVE--To determine the relation between sleeping position and quantity of bedding and the risk of sudden unexpected infant death. DESIGN--A study of all infants dying suddenly and unexpectedly and of two controls matched for age and date with each index case. The parents of control infants were interviewed within 72 hours of the index infant''s death. Information was collected on bedding, sleeping position, heating, and recent signs of illness for index and control infants. SETTING--A defined geographical area comprising most of the county of Avon and part of Somerset. SUBJECTS--72 Infants who had died suddenly and unexpectedly (of whom 67 had died from the sudden infant death syndrome) and 144 control infants. RESULTS--Compared with the control infants the infants who had died from the sudden infant death syndrome were more likely to have been sleeping prone (relative risk 8.8; 95% confidence interval 7.0 to 11.0; p less than 0.001), to have been more heavily wrapped (relative risk 1.14 per tog above 8 tog; 1.03 to 1.28; p less than 0.05), and to have had the heating on all night (relative risk 2.7; 1.4 to 5.2; p less than 0.01). These differences were less pronounced in the younger infants (less than 70 days) than the older ones. The risk of sudden unexpected death among infants older than 70 days, nursed prone, and with clothing and bedding of total thermal resistance greater than 10 tog was increased by factors of 15.1 (2.6 to 89.6) and 25.2 (3.7 to 169.0) respectively compared with the risk in infants of the same age nursed supine or on their side and under less than 6 tog of bedding. CONCLUSIONS--Overheating and the prone position are independently associated with an increased risk of sudden unexpected infant death, particularly in infants aged more than 70 days. Educating parents about appropriate thermal care and sleeping position of infants may help to reduce the incidence of the sudden infant death syndrome.  相似文献   

11.

Background

There is a need for new vaccines for tuberculosis (TB) that protect against adult pulmonary disease in regions where BCG is not effective. However, BCG could remain integral to TB control programmes because neonatal BCG protects against disseminated forms of childhood TB and many new vaccines rely on BCG to prime immunity or are recombinant strains of BCG. Interferon-gamma (IFN-γ) is required for immunity to mycobacteria and used as a marker of immunity when new vaccines are tested. Although BCG is widely given to neonates IFN-γ responses to BCG in this age group are poorly described. Characterisation of IFN-γ responses to BCG is required for interpretation of vaccine immunogenicity study data where BCG is part of the vaccination strategy.

Methodology/Principal Findings

236 healthy Gambian babies were vaccinated with M. bovis BCG at birth. IFN-γ, interleukin (IL)-5 and IL-13 responses to purified protein derivative (PPD), killed Mycobacterium tuberculosis (KMTB), M. tuberculosis short term culture filtrate (STCF) and M. bovis BCG antigen 85 complex (Ag85) were measured in a whole blood assay two months after vaccination. Cytokine responses varied up to 10 log-fold within this population. The majority of infants (89–98% depending on the antigen) made IFN-γ responses and there was significant correlation between IFN-γ responses to the different mycobacterial antigens (Spearman''s coefficient ranged from 0.340 to 0.675, p = 10−6–10−22). IL-13 and IL-5 responses were generally low and there were more non-responders (33–75%) for these cytokines. Nonetheless, significant correlations were observed for IL-13 and IL-5 responses to different mycobacterial antigens

Conclusions/Significance

Cytokine responses to mycobacterial antigens in BCG-vaccinated infants are heterogeneous and there is significant inter-individual variation. Further studies in large populations of infants are required to identify the factors that determine variation in IFN-γ responses.  相似文献   

12.

Background

Although the number of newly detected leprosy cases has decreased globally, a quarter of a million new cases are detected annually and eradication remains far away. Current options for leprosy prevention are contact tracing and BCG vaccination of infants. Future options may include chemoprophylaxis and early diagnosis of subclinical infections. This study compared the predicted trends in leprosy case detection of future intervention strategies.

Methods

Seven leprosy intervention scenarios were investigated with a microsimulation model (SIMCOLEP) to predict future leprosy trends. The baseline scenario consisted of passive case detection, multidrug therapy, contact tracing, and BCG vaccination of infants. The other six scenarios were modifications of the baseline, as follows: no contact tracing; with chemoprophylaxis; with early diagnosis of subclinical infections; replacement of the BCG vaccine with a new tuberculosis vaccine ineffective against Mycobacterium leprae (“no BCG”); no BCG with chemoprophylaxis; and no BCG with early diagnosis.

Findings

Without contact tracing, the model predicted an initial drop in the new case detection rate due to a delay in detecting clinical cases among contacts. Eventually, this scenario would lead to new case detection rates higher than the baseline program. Both chemoprophylaxis and early diagnosis would prevent new cases due to a reduction of the infectious period of subclinical cases by detection and cure of these cases. Also, replacing BCG would increase the new case detection rate of leprosy, but this effect could be offset with either chemoprophylaxis or early diagnosis.

Conclusions

This study showed that the leprosy incidence would be reduced substantially by good BCG vaccine coverage and the combined strategies of contact tracing, early diagnosis, and treatment of infection and/or chemoprophylaxis among household contacts. To effectively interrupt the transmission of M. leprae, it is crucial to continue developing immuno- and chemoprophylaxis strategies and an effective test for diagnosing subclinical infections.  相似文献   

13.
Summary A previous paper has demonstrated that enhanced tumor-specific immunity could be induced by priming mice with Bacillus Calmette Guerin (BCG) and subsequently immunizing them with syngeneic tumor cells modified with BCG-cross-reactive muramyl dipeptide (MDP) hapten [15]. The present study establishes a tumorspecific immunotherapy protocol for a murine chronic leukemia based on the above T-T cell collaboration between antitumor effector T cells and anti-MDP hapten helper T cells induced by BCG priming. BALB/c mice which had been primed to BCG were injected intravenously (i.v.) with viable, syngeneic BCL1 leukemia cells. One week later, these mice were immunized intraperitoneally (i.p.) with unmodified or MDP hapten-modified, 10,000 R X-irradiated BCL1 cells, followed by 4 booster immunizations at 5-day intervals. The administration of unmodified BCL1 tumor cells into BCG-primed mice failed to prevent them from tumor death due to the persistent growth of preinjected BCL1 cells. In contrast, the immunization of BCG-primed, BCL1 leukemia-cell-bearing mice with MDP-modified BCL1 cells resulted in a high growth inhibition of leukemia cells and protection of these mice from death by leukemia. It was also revealed that potent tumorspecific, T-cell-mediated immunity was generated in mice which survived in this immunotherapy model. Thus, these results indicate that administration of MDP hapten-modified, syngeneic leukemia cells into leukemia-bearing mice which have been primed with BCG results in potent tumor-specific, T-cell-mediated immunity attributable to preventing the growth of disseminated leukemic cells.This work was supported by a Grant-in-Aid for the Special Project Cancer-Bioscience from the Ministry of Education, Science, and Culture, Japan Abbreviations used: TATA, tumor-associated transplantation antigens; MDP, muramyl dipeptide; MTP, muramyl tripeptide; BCG, Bacillus Calmette Guerin  相似文献   

14.
Tuberculosis is a major cause of death in mankind and BCG vaccine protects against childhood but not adult tuberculosis. BCG avoids lysosomal fusion in macrophages decreasing peptides required for activating CD4 T cells and Th1 immunity while suppressing the expression of MHC-II by antigen presenting cells (APCs). An in vitro model of antigen presentation showed that ligands for TLR-9, 7, 4 and 1/2 increased the ability of APCs to present antigen-85B of BCG to CD4 T cells, which correlated with an increase in MHC-II expression. TLR-activation led to a down-regulation of MARCH1 ubiquitin ligase which prevents the degradation of MHC-II and decreased IL-10 also contributed to an increase in MHC-II. TLR-activation induced up-regulation of MHC-II was inhibited by the blockade of IRAK, NF-kB, and MAPKs. TLR-7 and TLR-9 ligands had the most effective adjuvant like effect on MHC-II of APCs which allowed BCG vaccine mediated activation of CD4 T cells.  相似文献   

15.
Mother-infant cannibalism in species of galagos as in several other species of non-human primates is a common phenomenon. In non-human primates kept in laboratory conditions many of the observed cases of cannibalism were not associated with starvation and with infanticide. Cannibalism in galagos was observed in at least five different species. In several laboratories, like the Duke University Primate Center, the frequencies of cannibalism in galagos species in captivity have been reduced by the isolation of pregnant female before the parturition from her companions, especially adult males. At the Primate Behaviour Research Group (University of Witwatersrand, Johannesburg, South Africa) three cases of cannibalism were observed in twoGalago crassicaudatus umbrosus' mothers before the end of the third day after birth. To understand the reasons why the mothers cannibalize their own infants, it was decided to analyze the mother-infant interaction which preceded the death of the infants. InGalago crassicaudatus twin and triplet births are very common. In one of our two observed mothers who cannibalized their infants, there was one triplet birth. In this study the two pregnant females were isolated in two separated cages ten days before giving birth. One of the two observed mothers gave birth to triplets, the other had a single birth. At the end all four infants were cannibalized. In all cases the cannibalization started after the infant's death. The infants' deaths were caused by lack of maternal care which caused them to starve. The results show that the triplet's mother differed in some of her behaviour towards her infants. In one of the cannibalized infants behaviours such asNipple andMother Passive Prevent were never seen before death. In our cases it seems that cannibalism was probably due to the laboratory condition that for generation to generation caused stress to the mothers and changed their maternal behaviours, which lead to the death of the offspring which after death became a consumable resource.  相似文献   

16.
Following complete remission of non-Hodgkin''s lymphoma by chemotherapy, irradiation or both, 44 patients were studied to assess the value of bacille Calmette-Guérin (BCG) as maintenance therapy. Patients with stage LI, EI or EII disease were allocated at random to receive BCG or no further maintenance therapy, and those with stage LII, LIII, EIII or IV disease received BCG therapy or orally administered cyclophosphamide. BCG had no effect on the duration of remission or the overall survival from the time of randomization. However, after the first recurrence there was a significant improvement in survival in the patients who had received BCG maintenance therapy.  相似文献   

17.
OBJECTIVES--To examine the factors which might explain the higher mortality from sudden infant death syndrome in Maori infants (7.4/1000 live births in 1986 compared with 3.6 in non-Maori children). DESIGN--A large nationwide case control study. SETTING--New Zealand. 485 infants who died of sudden infant death syndrome were compared with 1800 control infants. There were 229 Maori and 240 non-Maori cases of sudden infant death syndrome (16 cases unassigned) and 353 Maori and 1410 non-Maori controls (37 unassigned). RESULTS--Maori infants had 3.81 times the risk (95% confidence interval 3.06 to 4.76) of sudden infant death syndrome compared with non-Maori infants. The risk factors for sudden infant death syndrome within groups were remarkably similar. When Maori and non-Maori controls were compared the prevalence of many of the known risk factors was higher in Maori infants. In particular, mothers were socioeconomically disadvantaged, younger, and more likely to smoke and their infants were of lower birth weight and more likely to share a bed with another person. Multivariate analysis controlling for potential confounders found that simply being Maori increased the risk of sudden infant death syndrome by only 1.37 (95% CI = 0.95 to 2.01), not statistically significantly different from 1. Population attributable risk was calculated for prone sleeping position, maternal smoking, not breast feeding, and infants sharing a bed with another person. In total these four risk factors accounted for 89% of deaths from sudden infant death syndrome in Maori infants and 79% in non-Maori infants. CONCLUSION--The high rate of sudden infant death syndrome among Maori infants is based largely on the high prevalence in the Maori population of the major risk factors. Other risk factors, not related to ethnicity, probably explain remaining differences between Maori and non-Maori children.  相似文献   

18.
Young AKR mice grafted i.v. with 10(1) or 10(3) cells from spontaneous AKR thymomas were treated with repeated i.v. injections of BCG or subcutaneous injections of irradiated AKR thymoma cells. BCG often cured mice from graft leukemia, whereas the effect of irradiated thymoma cells was less effective. Mice that did not develop graft-leukemia after graft of 10(1) leukemia cells and BCG treatment showed a spontaneous leukemia in 30% of the cases later. Ninety percent of nongrafted mice developed spontaneous leukemia whether BCG-treated or not. General immune reactivity as assessed in individual mice by T and B lymphocyte mitogen tests as well as the hemolytic plaque-forming cell assay had no clear correlation to the effects of immune adjuvants in respect to survival. In contrast, occurrence of self-directed immune reactions were clearly correlated to survival and cure of grafted and BCG-treated mice as revealed by assays both in vitro and in vivo. However, 13 to 25% of the mice apparently cured of leukemia developed a wasting-like syndrome that sometimes terminated in death. The immplications of self-directed immune reactions as mediators of the anti-neoplastic effects of immunoadjuvants.  相似文献   

19.
Postmortem Human Brain pH and Lactate in Sudden Infant Death Syndrome   总被引:3,自引:3,他引:0  
Lactate and pH were measured in frontal and temporal cortex, cingulate gyrus, and caudate nucleus in brains from sudden infant death syndrome (SIDS) cases, control infants, and control adults. Both the lactate levels and the pH values were significantly correlated (p less than 0.001) between the four brain areas, whereas lactate and pH values were significantly correlated within each brain area (p less than 0.001) with a value of pH 7.2 for zero lactate. The lactate concentration in heart blood was significantly correlated with brain lactate (p less than 0.001). Adult sudden death cases (heart attacks) had low lactate and high pH values, whereas agonal state cases had high lactate and low pH values. Control infants who had died because of accidents also had low lactate and high pH values, but infants who might have been exposed to hypoxia before death had high lactate and low pH values. SIDS cases fell into two groups: the first, consisting of all victims over 30 weeks of age and about one-half to two-thirds of those aged less than 30 weeks, had low lactate and high pH values; the second group, consisting of about one-third to one-half of those less than 30 weeks old, had high lactate and low pH values. The changes in lactate levels and pH values indicate that the majority of SIDS cases had died suddenly, but that a sizeable minority had been exposed to hypoxia prior to death.  相似文献   

20.

Background

Monochorionic (MC) twins are at increased risk for perinatal mortality and serious morbidity due to the presence of placental vascular anastomoses. Cerebral injury can be secondary to haemodynamic and hematological disorders during pregnancy (especially twin-to-twin transfusion syndrome (TTTS) or intrauterine co-twin death) or from postnatal injury associated with prematurity and low birth weight, common complications in twin pregnancies. We investigated neurodevelopmental outcome in MC and dichorionic (DC) twins at the age of two years.

Methods

This was a prospective cohort study. Cerebral palsy (CP) was studied in 182 MC infants and 189 DC infants matched for weight and age at delivery, gender, ethnicity of the mother and study center. After losses to follow-up, 282 of the 366 infants without CP were available to be tested with the Griffiths Mental Developmental Scales at 22 months corrected age, all born between January 2005 and January 2006 in nine perinatal centers in The Netherlands. Due to phenotypic (un)alikeness in mono-or dizygosity, the principal investigator was not blinded to chorionic status; perinatal outcome, with exception of co-twin death, was not known to the examiner.

Findings

Four out of 182 MC infants had CP (2.2%) - two of the four CP-cases were due to complications specific to MC twin pregnancies (TTTS and co-twin death) and the other two cases of CP were the result of cystic PVL after preterm birth - compared to one sibling of a DC twin (0.5%; OR 4.2, 95% CI 0.5–38.2) of unknown origin. Follow-up rate of neurodevelopmental outcome by Griffith''s test was 76%. The majority of 2-year-old twins had normal developmental status. There were no significant differences between MC and DC twins. One MC infant (0.7%) had a developmental delay compared to 6 DC infants (4.2%; OR 0.2, 95% 0.0–1.4). Birth weight discordancy did not influence long-term outcome, though the smaller twin had slightly lower developmental scores than its larger co-twin.

Conclusions

There were no significant differences in occurrence of cerebral palsy as well as neurodevelopmental outcome between MC and DC twins. Outcome of MC twins seems favourable in the absence of TTTS or co-twin death.  相似文献   

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