[Investigation and analysis on the detection of IgG antibodies against the rubella virus among rural childbearing-age women in preconception period in Yunnan Province from 2013 to 2019]

A study was conducted on rural women of childbearing age aged 20-49 who underwent the National Free Preconception Health Examination Project (NFPHEP)in Yunnan Province from 2013 to 2019. Descriptive analysis was conducted to determine the negative rate of IgG antibodies against the rubella virus and its differences among various socio-demographic characteristics. Among the 1 511 203 study subjects, the negative rate of IgG antibodies against the rubella virus was 24.36%. Only 2.64% of the population had received rubella virus vaccine. The negative rate of IgG antibodies among rural childbearing-age women in the preconception period in Yunnan Province decreased with age and educational level (Ptrend<0.001). The negative rate of IgG antibodies in ethnic minority women of childbearing age in the preconception period (25.19%) was higher than that of Han women (23.88%). Among the 22 ethnic groups with over 1 000 participants, the negative rates of IgG antibodies in women of childbearing age from the Blang (32.85%), Bouyei (31.03%), Zhuang (31.01%), and Miao (30.70%) ethnic groups were higher than those of women from other ethnic groups. Among the 16 states (cities) in Yunnan Province, the negative rate of IgG antibodies in pregnant women of childbearing age in Wenshan Zhuang and Miao Autonomous Prefecture (38.06%) and Lincang City (32.63%) was higher than that in other states (cities). The negative rate of serum IgG antibodies in women who reported having received rubella virus vaccine (18.60%) was lower than that in other non-vaccinated populations (24.52%). The proportion of rural women of childbearing age in Yunnan Province who were susceptible to the rubella virus before pregnancy was still high. It is necessary to promote rubella vaccination among people susceptible to rubella, especially pregnant women, to prevent rubella virus infection and reduce the incidence rate and disease burden of rubella people.

Identification of Critical Amino Acids of Coxsackievirus A10 Associated with Cell Tropism and Viral RNA Release during Uncoating

Coxsackievirus A10 (CV-A10) is a prevailing causative agent of hand-foot-mouth disease, necessitating the isolation and adaptation of appropriate strains in cells allowed for human vaccine development. In this study, amino acid sequences of CV-A10 strains with different cell tropism on RD and Vero cells were compared. Various amino acids on the structural and non-structural proteins related to cell tropism were identified. The reverse genetic systems of several CV-A10 strains with RD+/Vero- and RD+/Vero+ cell tropism were developed, and a set of CV-A10 recombinants were produced. The binding, entry, uncoating, and proliferation steps in the life cycle of these viruses were evaluated. P1 replacement of CV-A10 strains with different cell tropism revealed the pivotal role of the structural proteins in cell tropism. Further, seven amino acid substitutions in VP2 and VP1 were introduced to further investigate their roles played in cell tropism. These mutations cooperated in the growth of CV-A10 in Vero cells. Particularly, the valine to isoleucine mutation at the position VP1-236 (V1236I) was found to significantly restrict viral uncoating in Vero cells. Co-immunoprecipitation assays showed that the release of viral RNA from the KREMEN1 receptor-binding virions was restricted in r0195-V1236I compared with the parental strain r0195 (a RD+/Vero+ strain). Overall, this study highlights the dominant effect of structural proteins in CV-A10 adaption in Vero cells and the importance of V1236 in viral uncoating, providing a foundation for the mechanism study of CV-A10 cell tropism, and facilitating the development of vaccine candidates.

[Effect of transcranial direct current stimulation on neurological injury markers and prognosis in patients with acute and severe carbon monoxide poisoning]

Objective: To observe the effects of transcranial direct current stimulation (tDCS) on nerve injury markers and prognosis in patients with acute severe carbon monoxide poisoning (ASCOP) . Methods: In May 2021, 103 ASCOP patients were treated in the emergency department of Harrison International Peace Hospital of Hebei Medical University from November 2020 to January 2021. The patients were divided into two groups according to whether they received tDCS treatment. The control group (50 cases) were given oxygen therapy (hyperbaric oxygen and oxygen inhalation) , reducing cranial pressure, improving brain circulation and cell metabolism, removing oxygen free radicals and symptomatic support, and the observation group (53 cases) was treated with 2 weeks of tDCS intensive treatment on the basis of conventional treatment. All patients underwent at least 24 h bispectral index (BIS) monitoring, BIS value was recorded at the hour and the 24 h mean value was calculated. Neuron-specific enolase (NSE) and serum S100B calcium-binding protein (S100B) were detected after admission, 3 d, 7 d and discharge. Follow-up for 60 days, the incidence and time of onset of delayed encephalopathy (DEACMP) with acute carbon monoxide poisoning in the two groups were recorded. Results: The NSE and S100B proteins of ASCOP patients were significantly increased at admission, but there was no significant difference between the two groups (P=0.711, 0.326) . The NSE and S100B proteins were further increased at 3 and 7 days after admission. The increase in the observation group was slower than that in the control group, and the difference was statistically significant (P(3 d)=0.045, 0.032, P(7 d)=0.021, 0.000) ; After 14 days, it gradually decreased, but the observation group decreased rapidly compared with the control group, with a statistically significant difference (P=0.009, 0.025) . The 60 day follow-up results showed that the incidence of DEACMP in the observation group was 18.87% (10/53) , compared with 38.00% (19/50) in the control group (P=0.048) ; The time of DEACMP in the observation group[ (16.79±5.28) d] was later than that in the control group[ (22.30±5.42) d], and the difference was statistically significant (P=0.013) . Conclusion: The early administration of tDCS in ASCOP patients can prevent the production of NSE and S100B proteins, which are markers of nerve damage. and can improve the incidence and time of DEACMP.

[Postoperative care of a retrograde cuff avulsion injury of finger skin treated by microsurgical reimplantation]

Sheath avulsion of finger skin is a serious acute occupational hand injury. Most of them are mechanical injuries, which are difficult to deal with clinically, have many complications, and can lead to serious hand deformities and dysfunction. Microsurgical replantation is the main treatment for finger skin retrograde sleeve avulsion injury, but postoperative fine nursing and scientific personalized vocational rehabilitation are the key to affect the surgical effect and patients' return to society and work. In this paper, 16 patients with retrograde sheath avulsion of finger skin were followed up for 6-12 months. The motor function of the injured finger was evaluated by total active motion of patient finger (TAM) , and the effect of postoperative fine nursing measures was analyzed.

[Analysis of EGFR mutation and clinical features of lung cancer in Yunnan]

Objective: To analyze the EGFR mutation profile of lung cancer patients in Yunnan, and to provide evidence for clinical personalized treatment. Methods: Demographic and clinical data of 2 967 lung cancer patients undergoing EGFR identification were collected and analyzed from January 2014 to August 2019 in Yunnan Cancer Hospital. Results: The proportion of EGFR mutation in 2 967 patients with lung cancer was 46.2%. Univariate analysis showed that the proportion of EGFR mutation in women was higher than that in men (P<0.001) and displayed a downward trend with age (P=0.03). The mutation rate of ethnic minorities was higher than Han (P=0.012). Mutation rate in patients without smoking history was higher than those with smoking history (P<0.001), and patients without drinking history was higher than patients with drinking history (P<0.001). Mutation rate in patients without family history of lung cancer was higher than those with family history (P=0.008). The mutation rate of adenocarcinoma was higher than other pathological types (P<0.001). The mutation rate was different among stages, and it was higher in early patients than that in advanced patients (P<0.001). The mutation rate of tissue specimens was higher than those of cytology and peripheral blood samples (P<0.001). The mutation rate of Xuanwei area was lower than that in non-Xuanwei area (P<0.001). Multivariate analysis showed that gender (P<0.001), age (P=0.036), smoking history (P<0.001), pathological type (P<0.001), specimen type (P<0.001), and whether or not Xuanwei area (P<0.001) were the independent factors of EGFR mutation.The EGFR mutation was more common in female, non-smokers, adenocarcinoma, non-Xuanwei area, tissue specimen and young lung cancer patients.The mutation types of EGFR in 1 370 cases mainly included 19-Del and L858R. The predominant mutation of EGFR in Xuanwei area was L858R, while in non-Xuanwei area was 19-Del.The mutation rates of G719X, G719X+ L861Q, G719X+ S768I, and S768I in Xuanwei were higher while the mutation rates of 19-Del, L858R, and 20-ins were lower than non-Xuanwei area (P<0.05). The 19-Del mutation rate of ethnic minorities is higher than that of Han (P<0.001). The combined mutation rate of G719X, L861Q in Han was higher than that of ethnic minorities (P=0.005). Conclusions: The EGFR mutation rate in lung cancer patients in Yunnan is similar to Asian and Chinese, and higher in female, non-smokers, adenocarcinomas, young and non-Xuanwei area patients. The most common types of EGFR mutation in Yunnan are 19-Del and L858R. The predominant mutation of EGFR in Xuanwei area is L858R, while in non-Xuanwei area is 19-Del. The mutation rates of G719X, G719X+ L861Q, G719X+ S768I and S768I are higher in Xuanwei patients than those in non-Xuanwei patients. The combined mutation rate of G719X and L861Q in Han nationality is higher than that of ethnic minorities.

[Assessment of sleep-disordered breathing using hypoxia index]

Objective: To analyze the clinical significance of hypoxia index (HI) in assessing the severity of hypoxemia in obstructive sleep apnoea hypopnea syndrome(OSAHS). Methods: A total of 127 patients with a complaint of snoring visiting our hospital were recruited from February 2014 to January 2016. All patients received polysomnography (PSG) test. The PSG results were analyzed by a technician and the SpO(2) data were analyzed by a pre-designed computer software. The patients were grouped according to apnea hypopnea index (AHI) and lowest oxygen saturation (LSpO(2)) respectively. Receiver operating characteristic (ROC) curve was used to evaluate the best HI diagnostic value. Results: The HI (median) of the simple snoring, mild, moderate and severe OSAHS groups (according to AHI) were 0.027(0.004, 0.554), 0.281(0.045, 0.353), 0.429(0.099, 1.677), 21.714(2.737, 95.473), respectively. There were statistically significant correlation between HI and AHI, LSpO(2), ≥3% oxygen desaturation index(ODI(3)), the correlation coefficient being 0.78, -0.92, 0.87(U value were 8.76, -10.34, 9.72, all P<0.01). Grouped according to LSpO(2), the HI was significantly different between groups (H value were 7.62-14.39, all P<0.05). Conclusion: If the HI diagnostic value was set reasonably, it might be used as an effective index for evaluating the severity of OSAHS.

[Clinical outcomes of cervical disc herniation treated by posterior percutaneous endoscopic cervical discectomy]

Objective: To evaluate the clinical outcomes of posterior percutaneous endoscopic cervical discectomy (PPECD) for cervical disc herniation. Methods: A total of 23 patients who underwent PPECD for cervical disc herniation at Department of Spine Surgery, Guangdong Provincial Hospital of Chinese Medicine from August 2014 to April 2016 were reviewed. The mean age of the 17 males and 6 females was 49.5 years (range from 31 to 61 years). All patients had unilateral upper limb radiating symptoms, 13 patients with right upper limb radiating pain and 10 patients with left upper limb radiation pain, 17 patients with neck pain symptoms. Responsible segment: left C(4-5) 1 case, right C(4-5) 2 cases, left C(5-6) 4 cases, right C(5-6) 8 cases, left C(6-7) 5 cases, right C(6-7) 3 example.Operating time, length of hospitalization, complications, neck and arm Visual analog scale(VAS), and Neck Disability Index(NDI) were evaluated. The excellent and good rate of surgery was evaluated by using the Odom criteria. Harrison method was used to measure cervical curvature. The Cobb angle of the surgical segment was measured on the X-ray, and the range of motion (ROM) was calculated. The changes of the cervical curvature and the surgical segment ROM were compared pre- and post-operation. Results: The operation time was 94.1 min (range from 80 to 150 min). The average length of hospital stay was 4.8 days. The mean follow-up period was 23.5 months (range from 15 to 35 months). The preoperative arm VAS score was 6.95±0.88, 1-week postoperative arm VAS score was 2.09±0.67, the last follow-up arm VAS score was 1.04±0.98. The preoperative neck VAS score was 3.04±0.77, 1-week postoperative neck VAS score was 1.52±0.51 and the last follow-up neck VAS score was 0.61±0.78. The 1-week postoperative and last follow-up arm and neck VAS scores were significantly reduced compared with pre-operation (P<0.01). Compared with 1 week after surgery, the last follow-up of the arm and neck VAS score further reduced, the difference was statistically significant (P<0.01). The preoperative NDI was (58.52±4.98)%, the 1-week postoperative NDI was (33.74±4.72)%, the last follow-up NDI was (19.22±3.23)%. The 1-week postoperative and last follow-up NDI was significantly improved compared with pre-operation (P<0.01). Compared with 1 week after surgery, the last follow-up of the NDI further improved, the difference was statistically significant (P<0.01). The 1-week postoperative cervical curvature was (14.65±2.89)°, and it was improved compared with preoperative(14.23±3.06)°, the difference was statistically significant (P<0.05) . The last follow-up was cervical curvature(14.64±2.68)°, there was no significant difference compared with preoperative (P> 0.05). The preoperative surgical ROM was(5.37±1.83)°, 1-week postoperative was(5.53±1.52)°, and the last follow-up was (5.62±1.48)°, there was no significant difference pre-operative and post-operation (P> 0.05). The excellent and good rate was 91.3% (excellent in 16 cases, good in 5 cases, 2 cases). There was no nerve root injury, cerebrospinal fluid leakage, wound infection, and other complications. Conclusions: PPECD is a sufficient and safe supplement for cervical disc herniation, its recent clinical efficacy was good. And it has no significant effect on cervical stability.

[Clinical effectiveness of salvianolic acid B and triamcinolone acetonide in treatment of oral submucous fibrosis]

Objective: To evaluate the clinical effectiveness of salvianolic acid B (SA-B) and triamcinolone acetonide (TA) by means of combined intralesional injection in the treatment of oral submucous fibrosis (OSF). Methods: According to clinical findings and symptoms, TA combined with SA-B were consecutively applied intralesionally 1 time weekly for 30 times. Mouth opening degree, color change of the buccal mucosae and numeral increase of the capillary vessels were determined by degree Ⅰ-Ⅳ visual analog scale were evaluated at 12, 24, and 36 months, respectively. Results: One hundred and fourteen subjects fulfilled the study without obvious adverse reactions. After treatment for 1 year, the net gain in mouth opening of the early stage group was (5.5 ± 1.5) mm at 12 months, (8.8 ± 1.6) mm at 24 months and (12.0±1.2) mm at 36 months. The net gain in mouth opening of the middle stage group were (5.3±1.7) mm at 12 months, (10.5±1.5) mm at 24 months and (14.5±2.4) mm at 36 months. The net gain in mouth opening of the advanced stage group were (5.7±1.3) mm at 12 months, (13.7±1.3) mm at 24 months and (15.5±1.5) mm at 36 months. The effective rates of color change of the buccal mucosae and numeral increase of the capillary vessels after treatment for 36 months were 100% in early stage group, 93% (51/55) in middle stage group and 90% (36/40) in advanced stage group. Conclusions: TA and SA-B combined intralesional injection in the treatment of oral submucous fibrosis is effective.

[Expression of nucleolar protein 14 and CD31 in pancreatic cancer mouse model and its correlation with tumor progression]

Objective: To investigate expression of nucleolar protein 14(NOP14) and CD31 in pancreatic cancer mouse model and its correlation with tumor progression. Methods: Clinicopathological data of 5 patients with pathologically confirmed pancreatic ductal adenocarcinoma(PDAC) and hepatic metastasis between January 2013 and December 2015 was collected in Department of General Surgery, Peking Union Medical College Hospital. Immunohistochemistry staining was employed to detect the expression of NOP14 in matched primary PDAC and relevant metastasis.Pancreatic cancer cells with NOP14 stably knocked down were established by transfecting lentivirus with NOP14 targeted silencing RNA.The inhibition efficacy was detected by quantitative real time PCR and western blot.Microvascular density(MVD) in pancreatic cancer transplantation mouse model was determined by CD31 immunohistochemistry staining analysis and correlated with NOP14 expression and tumor progression. Results: NOP14 had a significant higher expression in liver metastasis than primary pancreatic adenocarcinoma (2.09±0.45 vs. 1.31±0.27, P=0.028). NOP14 was knocked down 86 percent on mRNA level determined by qPCR and 78 percents on protein level detected by western blot. MVD was significantly decreased in NOP14-inhibited tumor from both pancreatic cancer cells subcutaneously and orthotopically grafted tumor mouse model with the value of 61.40±13.85 vs. 85.53±14.59 (P=0.041) and 38.33±10.91 vs. 59.33±15.37(P =0.037), respectively. Besides, MVD was positively associated with tumor volume(r=0.842, P<0.01) and metastasis (r=0.726, P=0.008). Conclusion: NOP14 presents higher expression in hepatic metastasis of pancreatic adenocarcinoma and might promote tumor progression by increasing microvascular density.

[Clinical analysis of delayed epistaxis after craniofacial trauma in 16 patients]

Objective:To investigate the etiology,clinical presentations,diagnosis and treatment of delayed epistaxis after craniocerebral trauma.Method:A retrospective analysis was made including 16 cases who had the traumatic carotid artery injury with massive delayed epistaxis.All of them were finally diagnosed by digital substraction angiography(DSA).Final clinical outcome,radiographic data and follow-up data were analyzed.Result:Two cases of traumatic pesudoaneurysm from internal maxillary artery were embolized with polyvinyl alcohol particles and gelatin sponge.Fourteen cases of traumatic pesudoaneurysm located in ICA cavernous segment was embolized by covered stent.The covered stent placement was successful in all 14 pseudoaneurysms.No procedure-related complications or deaths occurred during follow-up except one of the case with visual field defects and another case with vision loss.Conclusion:Patients with delayed massive epistaxis or recurrent epistaxis after craniofacial trauma which cause pesudoaneurysm should undergo CTA,MRA or DSA examination,and it is would help to get proper diagnosis and treatment as early as possible.No recurrence was found after successful endovascular techniques.

Direct measurement of precipitate induced strain in an Al-Zn-Mg-Cu alloy with aberration corrected transmission electron microscopy

Precipitates and their associated strain fields significantly influence mechanical properties and, consequently, the industrial performance of aluminum alloys. In this work, we present a direct measurement of strains induced by η' and η precipitates in an Al-Zn-Mg-Cu alloy using aberration-corrected high-resolution transmission electron microscopy and quantitative strain analysis. The results demonstrate that the strain induced by precipitates in the Al-Zn-Mg-Cu alloy shows significant tensile strains perpendicular to the longitudinal direction of the precipitate discs on the side of the discs and along the longitudinal direction at both ends of the η' and η precipitates. This strain field can be described by an equivalent dislocation model, in which the lattice mismatch between the precipitate and the matrix is equivalent to a series of dislocation pairs along the precipitate/matrix interfaces.

Edaravone protects endotoxin-induced liver injury by inhibiting apoptosis and reducing proinflammatory cytokines

Studies have shown that edaravone may prevent liver injury. This study aimed to investigate the effects of edaravone on the liver injury induced by D-galactosamine (GalN) and lipopolysaccharide (LPS) in female BALB/c mice. Edaravone was injected into mice 30 min before and 4 h after GalN/LPS injection. The survival rate was determined within the first 24 h. Animals were killed 8 h after GalN/LPS injection, and liver injury was biochemically and histologically assessed. Hepatocyte apoptosis was measured by TUNEL staining; proinflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)] in the liver were assayed by ELISA; expression of caspase-8 and caspase-3 proteins was detected by Western blot assay; and caspase-3 activity was also determined. Results showed that GalN/LPS induced marked elevations in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Edaravone significantly inhibited elevation of serum AST and ALT, accompanied by an improvement in histological findings. Edaravone lowered the levels of TNF-α and IL-6 and reduced the number of TUNEL-positive cells. In addition, 24 h after edaravone treatment, caspase-3 activity and mortality were reduced. Edaravone may effectively ameliorate GalN/LPS-induced liver injury in mice by reducing proinflammatory cytokines and inhibiting apoptosis.

Syntheses, Thermal Stability, and Structure Determination of the Novel Isostructural RBa3B9O18 (R = Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb)

A novel borate compound YBa(3)B(9)O(18) has crystallized in a melt of BaYB(9)O(16). Single-crystal X-ray diffraction measurements reveal that YBa(3)B(9)O(18) adopts a hexagonal space group P6(3)/m with cell parameters of a = 7.1761(6) A and c = 16.9657(6) A. The structure is made up of the planar B(3)O(6) groups parallel to each other along the (001) direction, regular YO(6) octahedra, and irregular BaO(6) and BaO(9) polyhedra to form an analogue structure of beta-BaB(2)O(4). A series of isostructural borate compounds RBa(3)B(9)O(18) (R = Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb) were prepared by powder solid-state reactions. The DTA and TGA curves of YBaB(9)O(16) show an obvious weight loss at about 955 degrees C associated with a decomposition into YBO(3), B(2)O(3), and YBa(3)B(9)O(18) due to its incongruent melting behavior. The DTA and TGA curves of YBa(3)B(9)O(18) show that it is chemically stable and a congruent melting compound. A comparison of the structures of YBa(3)B(9)O(18) and beta-BaB(2)O(4) is presented.

Lifestyle factors and human lung cancer: an overview of recent advances (review)

This article presents a review on the association between certain lifestyle characteristics and the risk for lung cancer in humans, using information derived primarily from epidemiological studies. Emphasis will be placed on more recently identified risk factors such as exposure to indoor air pollutants, psychosocial and behavioral influences, diet preferences, and fat intake. More traditional lifestyle factors such as cigarette smoking, occupation, and exposure to outdoor air pollutants will not be reviewed since their association with an increased risk for human lung cancer has been relatively well characterized and extensively reported. Evidence to date suggests that the indoor environment, life's events, and food choices may play a potentially important, albeit varying, role in the etiology of human lung cancer.

Combined intramuscular-intradermal protocol of universal neonate HB vaccination irrespective of mother's status of HBsAg

To evaluate a protocol of combined intramuscular-intradermal (i.m.-i.d.) universal hepatitis B (HB) vaccination of neonates regardless of the mothers' HB surface antigen HBsAg status, 160 full-term newborn babies were sequentially divided into groups A and B (test and control groups). The group A babies were immunized by giving 30 micrograms HB vaccine i.m. within 24 h after birth and 2 micrograms i.d. twice at 1 and 6 months of age. Group B babies were immunized by giving one initial dose of 30 micrograms i.m. and two booster doses of 10 micrograms i.m. after same 0, 1, 6-month schedule. Blood samples were collected at birth before the first dose of the HB vaccine, at 6 months of age before the third dose and at 12 months. The blood samples were tested for HBsAg and anti-HBs by using Abbott RIA reagents. All of the 160 newborns received three doses of vaccine, but in only 96 of them was the blood examination completed. The positive rate of anti-HBs > 10 IU l-1 was 76.27 and 83.08% in groups A and B, respectively at 6 months, and 83.72 and 92.45%, respectively at 12 months. The geometric mean titres (GMT) of anti-HBs was 42.25 and 60.25 IU l-1 in groups A and B, respectively at 6 months, and 74.45 and 87.1 IU l-1, respectively at 12 months. HBsAg was negative in the two groups 6 and 12 months after birth. The chi 2 and t-tests showed there were no significant differences in these data between the two groups. Thus was it demonstrated that the combined i.m.-i.d. protocol using 34 micrograms of HB vaccine can produce a protection similar to that of the conventional 50 micrograms i.m. regimen, while ca on-third of the vaccine can be saved. The new protocol is theoretically rational and may be ideal according to the cost-effectiveness principle.

Some lifestyle factors in human lung cancer: a case-control study of 792 lung cancer cases

In order to investigate the relationship between some lifestyle factors and lung cancer, a case-control study involving all lung cancer deaths registered in 1986 was performed. The results show that among males, 92.5% of the cases and 75.5% of controls were smokers, implying that cigarette smoking is a primary risk factor for lung cancer in males. By contrast, among females only 60.6% of the cases and 30.8% of the controls were smokers, implying factors other than cigarette smoking must be involved in the development of lung cancer in females. The risk of lung cancer in nonsmoking females was found to be unaffected by exposure to environmental tobacco smoke (ETS). A study of diet and eating habits showed that in males the risk of lung cancer was reduced by the intake of vegetables and fruits, but was significantly increased by a frequent intake of fried foods. The positive association between the intake of fried food and the risk of lung cancer could result from cooking practices and from inappropriate methods used in food preparation. No association can be demonstrated between the consumption of high protein or high fat diets, salty and smoked food items and the incidence of lung cancer. Thus, it is not likely that sufficient lung cancer inducing carcinogens can be generated through the intake of food. In addition, the positive association found to exist between the living index and the risk of lung cancer in females is consistent with the notion that coal smoke or cooking practices may generate sufficient indoor air pollutants to significantly increase the risk of lung cancer in females.

Summary of papers and research recommendations presented at the International Symposium on Lifestyle Factors and Human Lung Cancer, Guangzhou, China

This paper summarizes the themes and recommendations that emerged from the papers presented at the "International Symposium on Lifestyle Factors and Human Lung Cancer". In terms of our current knowledge, the following are considered important: (1) recognition and confirmation of lung cancer as a multifactorial disease; (2) the strong association known to exist between cigarette smoking and lung cancer does not explain the observation that the lung cancer death rate is lower than the smoking rate in certain groups of individuals, e.g. Chinese farmers; (3) the high incidence of adenocarcinoma in non-smoking women, e.g. Chinese housewives, suggests that factors other than cigarette smoking are involved for the development of lung cancer; (4) indoor air pollution is a significant risk factor for lung cancer in China; (5) there is incomplete information on the chemical nature and exposure assessment of indoor air pollutants; and (6) the need to better define the role of diet and nutrients as confounding factors for lung cancer. Based on the above, several recommendations were offered for continuing research to further our understanding of the etiology and pathogenesis of lung cancer.

An epidemiological study of risk factors for lung cancer in Guangzhou, China

Lung cancer has been on a rapid rise worldwide during the last three or four decades, in part due to modern social habits and unhealthy lifestyles. Although smoking, air pollution, and certain types of occupational exposure have been recognized as the major risk factors for lung cancer, the significance of each of these factors appears to vary with sex, country, and with region within a given country. In the case of nonsmoking females, some risk factors for lung cancer remain to be identified. In the city of Guangzhou, lung cancer is one of the five leading tumors and the rate has been increasing steadily in both males and females since the 1970s. In this report, more than 6000 cases of lung cancer deaths, accumulated over the past 9 years, were analyzed. The severity of air pollution and cigarette smoking were positively correlated with the incidence of lung cancer deaths. Analysis of levels of SO2 and NOx suggests that the major source of indoor air pollution came from cooking. Two studies were performed in order to determine the relative contribution and importance of smoking, indoor air pollution and occupational exposure as risk factors for the rising incidence of lung cancer. The first was a population-based case-control study involving 849 subjects (566 males and 283 females). The second study was based on the data made available by the Third National Census survey, in which the standardized mortality rate (SMR) and population attributable risk (PAR) for lung cancer due to occupational exposure for the population in Guangzhou were analyzed. Results of these two studies show that: in females, indoor air pollution, derived primarily from burning coal, was found to be a highly significant risk factor for lung cancer. In males, however, cigarette smoking and occupational exposure were significantly associated with lung cancer. To further elucidate the contribution of indoor air pollution as a risk factor for lung cancer in nonsmoking females, two additional case-control studies were performed in 1985 and 1986. The 1985 study involved 120 nonsmokers (28 males, 92 females) in which the influence of such lifestyle factors as: personal history of nonmalignant respiratory diseases, fresh vegetable consumption, lifetime occupation and occupational exposure histories, exposure to environmental tobacco smoke (ETS), degree of indoor air pollution, general conditions of home residence, cooking practices and environments, and family history of cancer were first individually assessed and then collectively subjected to multiple conditional regression analysis for evaluation as risk factors for lung cancer. The 1986 study involved 75 cases of never-smoking females in which the aim was to investigate the influence of exposure to spousal smoke as a risk factor for lung cancer. These studies suggest that consumption of fresh vegetables was a "protective" factor for lung cancer in both males and females. In females, indoor air pollution and size of the kitchen were risk factors for lung cancer, whereas ETS exposure, respiratory disease history, family history of cancer, living conditions, use of cooking fuel, and participation in cooking, were not statistically associated with female lung cancer deaths. Occupational exposure was also correlated with the incidence of female lung cancer deaths. In males, chemists had the highest SMR, whereas in females, homemakers had the highest SMR. In males, the most common lung cancer cell type was squamous cell carcinoma, whereas in females adenocarcinoma was the most predominant type. The factors affecting the distribution of histologic lung cancer cell types were also investigated and discussed.

The observation of some biological characteristics of transformed cells induced by MNNG in vitro

The early passage diploid Syrian hamster embryo (SHE) cells were treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The treated cells proliferated rapidly; the doubling times shortened; colonies appeared in solid agar medium and transformed foci formed in tissue culture. All of these phenomena suggest that malignant transformation of SHE cell has occurred. Faster cell division rate and multipolar mitosis were demonstrated by time-lapse cinemicrography and scanning electron microscopy. Multipolar mitosis can occur in two forms: direct division and indirect division. The transformed cells were more abundant in microvilli, the number of which increased in accordance with the degree of malignancy. In comparison with the controls, the transformed cells expressed a greater tritiated thymidine incorporation, greater DNA contents and more chromosomes, but no difference in nuclear area. The determination of amino acid changes in media due to the growth of transformed cells showed that the decrease in arginine and increase in ornithine are significant. The results of allogenic animal inoculation suggest that the transformed cells can be characterized into several different stages in the process of transformation.