Maximising the potential of Chinese birth cohort studies: a systematic review of mother-baby cohorts in mainland China.

OBJECTIVES: There is now a growing interest in early-life influences on adult diseases in China. A number of birth cohorts have been established. This systematic review provided a better understanding of the development of mother-baby cohorts in China. STUDY DESIGN: Systematic review. METHODS: We conducted a systematic review for research or profile papers in English/Chinese that reported data from mother-baby cohorts in mainland China, with ≥1y follow-up after birth. We identified 315 papers, corresponding to 31 cohorts from 19 provinces/megacities. RESULTS: All cohorts started in 1999-2017 (21 after 2010) and were set up with broad objectives or specific scientific focus. The baseline sample size varied, from <500 to >300,000 mothers. A majority of cohorts were initiated during pregnancy and followed children to <10y, only six to adolescence and none into adulthood. These cohorts mostly collected samples from mothers and babies, in addition to using interviews/questionnaires to collect information about pregnancy, birth and child health. Most cohorts were recruited from a single province/city. The large western region was understudied. CONCLUSIONS: Mother-baby cohorts have developed rapidly in China, but usually with a short follow-up duration. Extending the follow-up of children and developing cross-cohort collaboration will increase the diversity, size and coverage of the sample, allow studying early influences on life-course health and identify targets for early intervention in the Chinese population.

Impact of Swiss needle-cast on growth of Douglas-fir.

Phaeocryptopus gaeumannii, the cause of Swiss needle-cast, is widely distributed in plantations of Douglas-fir in many parts of the world. Nevertheless, information remains limited on its precise effect on stand growth, particularly in relation to regional climate, and on its consequent economic cost. In New Zealand, the spread of P. gaeumannii over a period of ≈30 years following its discovery in 1959 was closely monitored, and the timing of its arrival in different forests is known. This information was coupled with data from permanent sample plots in order to quantify the associated historical growth increment loss. Analyses revealed a steady decline in growth rate over the period from the first appearance of P. gaeumannii to a point when it stabilized at a lower increment level 14 to 20 years later. The cumulative mean reduction was 25% for mean top height, 27% for basal area, and 32% for stem volume. Volume growth rate decline was greater in the North Island (35%) than the South Island (23%) of New Zealand. These reductions in volume growth are estimated to equate to a loss in net present value of $NZ2,620 ha(-1) and $NZ1,470 ha(-1) for the North and South Islands, respectively, using a discount rate of 6%. Mortality did not increase as a result of infection by P. gaeumannii. The disease had less effect on cooler sites, especially those with low spring minimum temperatures (P < 0.001). Negligible growth decline occurred on sites with daily minimum October temperatures averaging <3.2°C.

Increased risk of cancer mortality after vagotomy for peptic ulcer: a preliminary analysis.

Patients (1,643) undergoing vagotomy for peptic ulcer at York District Hospital were traced through the Office of Populations Censuses and Surveys (OPCS) and cause of mortality obtained for the 577 who had died. Expected mortality for the cohort was calculated using a years at risk calculation in 5 year bands. There was an excess risk of mortality from cancer of all sites (1.5-fold), stomach (1.6-fold), colorectum (1.7-fold), biliary tract (4.1-fold) and lung (1.6-fold). There was no excess risk or mortality from cancer of the oesophagus, pancreas and female breast. The numbers of deaths have been too few and length of follow-up too short to investigate latency. The findings are consistent with the production of carcinogens as a result of the hypoacidity following vagotomy.

The association between typhoid carriage, typhoid infection and subsequent cancer at a number of sites.

It has been demonstrated that bacteria can produce the very potent carcinogens (N-nitroso compounds), from nitrite and suitable amines. It has been hypothesized that this can happen whenever a body site which is normally sterile becomes colonized by bacteria. If this is so then such chronic infections should result in an increased incidence of local cancers and also of cancers at some distant sites. To test this we studied the risk of cancer at various sites in a cohort of chronic carriers of Salmonella typhi/paratyphi. We have observed a greatly increased risk of cancers of the biliary tract and also of cancers of the colorectum, pancreas, lung and all sites. The results are discussed in terms of the hypothesis being tested.

Near-ultraviolet mutagenesis in superoxide dismutase-deficient strains of Escherichia coli.

We compared mutagenic spectra induced by polychromatic near-ultraviolet radiation (near-UV; 300-400 nm) with superoxide anion (O2-) -dependent mutagenesis using a set of Escherichia coli tester strains. Near-UV radiation produced increased frequencies of G:C to A:T transitions, G:C to T:A and A:T to T:A transversions, and small increases in frameshift mutations in wild-type cells. Tester strains lacking superoxide dismutase (SOD) activity (sodAsodB double mutants) demonstrated high spontaneous mutation frequencies and increased near-UV sensitivity. The double mutants also showed increased mutations induced by near-UV compared to either isogenic wild type, sodA or sodB single mutants. Furthermore, these mutants had an unusual spontaneous mutation spectrum, with a predominance of A:T to T:A transversions, followed by G:C to T:A transversions and frameshifts generated in runs of adenines in both the +1 and -1 direction. Other frameshifts were detected to a lesser degree. The oxygen dependency and the type of mutations spontaneously induced in SOD-deficient cells indicated that this mutagenic spectrum was caused by oxidative DNA damage. However, no apparent synergistic action between near-UV radiation and an increased flux of O2- could be detected. From the frequency and types of mutations induced by the two agents, we speculate that near-UV-induced mutagenesis and O2--dependent mutagenesis involve, in part, different lesion(s) and/or mechanism(s). The nature and possible mutagenic pathways of each are discussed.

Treatment of poorly controlled non-insulin-dependent diabetic patients with Acarbose.

Acarbose, 300 mg/day, was administered over one month in a cross-over trial to 18 hyperglycemic patients aged 41-66 years with non-insulin-dependent diabetes mellitus (NIDDM). All showed "normal" or exaggerated insulin release after a glucose challenge and remained in poor control (random glucose levels greater than or equal to 13 mmol/l) despite involvement in a diabetes intervention programme and prior use of oral hypoglycemic agents. During the one month treatment with Acarbose, fasting glucose and % HbAl concentrations were not different from those observed during placebo therapy. Furthermore, glucose tolerance was unchanged by Acarbose treatment. Glucose concentrations after a 1.6 MJ test meal were reduced by Acarbose from peak values of 17.3 +/- 1.0 to 15.0 +/- 1.1 mmol/l and were associated with lower post-prandial C-peptide (CPR) and insulin responses. Nevertheless, daily insulin production, as assessed by CPR excretion rates and plasma CPR and insulin concentrations, was not reduced by Acarbose. In fact, fasting plasma insulin and CPR levels were significantly higher during Acarbose then placebo therapy. Acarbose (100-400 mg/day) was continued for six months in 12 of these patients. During treatment, post-prandial glucose levels remained lower but monthly MBG values, determined by self-measurement of blood glucose, were unchanged except for small reductions in the 4th and 5th treatment months. % HbAl levels did not change. These data show that Acarbose treatment of a defined group of patients with poorly controlled NIDDM: resulted in small but sustained reductions of post-prandial glucose levels but without improving glucose tolerance, and reduced the circulating concentrations of insulin and CPR postprandially, but overall did not reduce daily production.

Patient equipment management: integrating a flexible alternative to purchase or lease.

As hospital CSS and OR departments work together to manage patient equipment, alternatives to purchase are available that can provide them with needed flexibility and responsiveness. A rental equipment provider that can meet the standards demanded for quality health care can become a valuable asset when developing and refining a hospitalwide equipment management program. But in order to receive the level of quality and service they should expect, hospitals must continually communicate their changing needs while holding their providers accountable to established standards.

Occupational and socioeconomic factors associated with peptic ulcer and with cancers following consequent gastric surgery.

Over 3000 patients, treated surgically for peptic ulcers, were assigned to a Social Class and Occupation Group using information obtained either from their death certificates or from their hospital notes. An analysis of the relationship of socioeconomic status and occupation with the site of original ulcer and the risk of cancer is reported. The major observations were: (a) an association of gastric ulcer with manual and of duodenal ulcer with non-manual Social Class; (b) an association of gastric cancer with dusty occupation and colorectal cancer with professional and managerial workers; and (c) no association between post-surgery gastric cancer risk and social class. This implies that the early stages of gastric carcinogenesis are related to poor socioeconomic conditions but the progression from the precursor lesion (in this case gastric ulcer) to gastric cancer is not, and is consistent with the multistage hypothesis of gastric carcinogenesis proposed by Correa [Diet and Human Carcinogenesis (Edited by Joosens, J. V., Hill, M. J. and Geboers, J.), pp. 109-115. Excerpta Medica, Amsterdam (1985)].