[An epidemiologic survey of blindness and low vision in persons over 45 years old in Doumen County]

An epidemiologic survey of blindness and low vision in persons over 45 years old in Doumen County, Guangdong Province was carried out in 1991. The sample size was 932 subjects. We found that the impairment of vision < 0.3 accounted for 10.94%. The prevalences of bilateral blindness and low vision were 1.61% and 3.22%, respectively. Both the prevalences of blindness and low vision were increased with age. The leading cause of blindness was cataract (45.20%) and the second, corneal opacity (16.70%).

[An epidemiologic survey on lens opacities in Doumen County]

Age-related lens opacity is the main cause of vision disability in elderly all over the world. A longitudinal study was designed to investigate the prevalence of lens opacity. 1,817 eyes of 932 adults over 45 year-old were sampled randomly. The lens opacities were graded according to a standardized photo of the Lens Opacities Classification System II (LOCS-II). The prevalence of lens opacities in nuclear color, nuclear opacity, cortical opacity and subcapsular opacity was 16.1%, 28.6%, 30.3% and 8.7% respectively. The frequency of all four types of opacities increased with age. The prevalence of lens opacities in four types were higher in female than that in male. The color of nuclear was related to the degree of myopia, the deeper the higher. These results are important information in eye care project.

[An epidemiological survey and treatment of blindness in Kaipin County of Guangdong Province]

An epidemiological survey of blindness was carried out in Kaipin County of Guangdong Province during October 1989 to May 1990, by stratified random cluster sampling. The sample population was 11,588, and the rate of blindness was 0.216%. The prevalence of blindness in persons aged 60 years and over was 48 times those of all other age groups combined. Since cataract accounted for 64% of the total blind cases, hence it was the key objective for surgical restoration of vision. Among 109 patients who were operated on for cataract, 83 cases were re-examined a half year later, and 78 cases (94%) had vision over 0.05.

[Observation on the early development of inoculated Brugia malayi microfilariae in mosquitoes]

This paper reports the early development and variation of inoculated Brugia malayi microfilariae in 3 groups of mosquitoes, i. e. young Anopheles sinensis, young Culex quinquefasciatus and old Cx. quinquefasciatus. Significant differences were observed among these groups. Sixty hours after inoculation, the percentage of normally developing filarial larvae in young An. sinensis was 72.3%; the percentage of melanized microfilariae in young Cx. quinquefasciatus was 75.4% and the percentage of filarial larvae which developed abnormally or remained in diapause status in old Cx. quinquefasciatus was 67.1%, each being much higher than that in the other groups. It was suggested that the immune competence of the mosquitoes had influence upon the filarial development. The intensity of the immune response not only varied with the species, but also diminished with the aging of mosquitoes.

Transferrin subtypes in 11 south China minority populations

Transferrin subtypes were determined by isoelectric focussing (IEF) in a total of 2,121 individuals from 11 South China minority populations. The C1, C2 and DCHI alleles were present in all the populations; B alleles were lacking, C4 was found in 3 populations and C3 in 6. C2 and C4 allele frequencies are notable in these minority groups. The frequency of the C2 allele was higher (0.25-0.38) than that of Han Chinese (0.18-0.25). In Bai the C2 frequency was as high as 0.38. The C4 allele was present at a low frequency (less than 0.01), which suggests that this allele probably existed in the ancestral Mongoloid population at a low frequency and increased in frequency in Amerindians due to genetic drift or other factors.

Clinical studies in the use of BCG and levamisole in the treatment of glomerulonephritis

Sixty patients with primary glomerulonephritis and nephrotic range proteinuria (most resistant to corticosteroid therapy) were given killed BCG inoculations as a major part of combined therapy with levamisole, 3 of every 7 days, and corticosteroids in 53 patients. Following treatment 80% of patients showed complete or partial remission of proteinuria with significant improvement in urinary protein excretion, serum albumin, blood urea, and serum creatinine. Thirteen of 15 patients followed up for 1-2 years and more had complete remission at the latest review, as did five of six patients followed for less than 1 year. The longer the course of the combined immunostimulant treatment, the lower the recurrence rate. The beneficial effects of retreatment in recurrent cases were much more rapid in onset than on initial treatment. The phagocytic function of monocytes was examined in a separate group of 24 patients with primary glomerulonephritis. Function was found to be significantly depressed but could be returned to normal following BCG inoculation. Associated with the improved monocyte phagocytic function there was a significant decrease in urinary protein excretion.

Protective role of BCG in the rabbit model of mesangial proliferative glomerulonephritis

A study was designed to investigate whether BCG could play a protective role in a rabbit model of mesangial proliferative glomerulonephritis. Fifteen rabbits were immunised with multiple injections of bovine serum albumin and their mononuclear phagocytic system was depressed by endotoxin from E. coli. The rabbits were divided into two groups: Group 1 (n = 7) received intravenous BCG from 3 weeks prior to the pathogenic immunisation and until the end of this period; Group 2 (n = 8) acted as a control and received normal saline. In the BCG group circulating immune complex (CIC) titres were significantly reduced, rabbit IgG deposition in glomeruli was significantly less, and mean glomerular cell counts were significantly less than those in the control group. We conclude that BCG stimulates the mononuclear phagocytic system to remove CIC and reduce the deposition of immune complexes in glomeruli, thereby mitigating the inflammatory response.

Quantitative studies on the development of inoculated Brugia malayi microfilariae in Anopheles sinensis and Culex quinquefasciatus

Definite numbers of B. malayi mf were inoculated into An. sinensis and Cx. quinquefasciatus, and their subsequent development was observed. The relationships between the dosage and the L3 positive rate on the one hand and the average filarial maturity rate on the other were defined. At the same dosages of 4 and 10 mf/mosquito, the L3 positive rates and the average filarial maturity rates in An. sinensis were much higher than those in Cx. quinquefasciatus (p less than 0.01). It was demonstrated that the immune response to filariae of the mosquitos was the main factor resulting in these differences. The intensity of the immune response not only varied with the species, but also declined with the aging of mosquitos. The results of our experiment might be useful to studies on the dynamics of filariasis transmission and the interaction between filariae and their insect hosts.

[Clinical observations and studies of BCG in the treatment of primary glomerulonephritis]

Sixty cases of nephrotic type of primary glomerulonephritis (PGN), who were mostly insensitive to the corticosteroids, received killed BCG inoculation as a main measure of combined therapy. After this treatment the complete and approximate remissions accounted for 80% in all. The urinary protein, serum albumin, BUN and SCr all had very significant improvement. As to those with similar pathologic and clinical findings, the therapeutic effects were much better in the BCG group than in the control. 13/15 cases followed up over 1-2 years had complete remission at the latest follow up and 5/6 followed below 1 year did so. The longer the courses of BCG, the lower the recurrence rates. The therapeutic effects of retreatment to those recurrent cases were much more rapid than those of initial treatment. The phagocytic function of the monocyte in another 24 PGN cases was studied. This function was found to be significantly depressed and could be normalized through BCG inoculation.

Optical properties of extremely thin films: studies using ATR techniques

The optical constants and optical properties of extremely thin ZnS, SiO(2), Al, and Ag films are studied and compared by attenuated total reflection (ATR) techniques. The optical constants and optical absorptance as a function of film thickness are measured. The experimental results agree well with theoretical prediction. It is found that there is no discontinuity in optical constants and absorptance when an extremely thin layer changes from isolated islands to a continuous film for all the measured materials. The critical thicknesses at which they form continuous films show great differences for the various materials and deposition methods. The dependence of absorptance on thickness of extremely thin layers is studied experimentally and theoretically.

Isolation and characterization of the cDNA for pulmonary surfactant-associated protein-B (SP-B) in the rabbit

Pulmonary surfactant contains phospholipids including dipalmitoyl-phosphatidylcholine and three surfactant-associated proteins designated SP-A, SP-B and SP-C. A cDNA for rabbit SP-B has been isolated from a fetal (30 days gestation) rabbit lung cDNA library constructed in lambda gt11. The cDNA and deduced amino acid sequences show strong homology with the cDNAs and predicted 40 kDa proproteins for human and canine SP-B. Strong homology is also observed with the amino acid sequences directly determined for the mature 8 kDa bovine and porcine SP-B isolated from lung lavage. SP-B is remarkable for its high cysteine and proline content and for the hydrophobic nature of the organic solvent-soluble, mature protein. In vitro translation of sense but not antisense RNA transcribed from the cDNA led to the production of 40 kDa and 32 kDa proteins. These proteins were immunoprecipitated by an antibody raised against bovine SP-B. Northern blot analysis revealed the mRNA for rabbit SP-B appears in fetal rabbit lung late in gestation and falls slightly in the neonate.

Polymorphisms of Pi, Hp, ADA and AK in Mongolian, Korean and Zhuang populations of China

Three minority ethnic groups from China, Mongolian, Koreans, and Zhuangs were studied for the genetic markers AK, ADA, Hp, and Pi. AK was monomorphic in Koreans and Zhuangs. Significant differences were observed in the Hp system between Mongolians and Zhuangs.

Distribution of eight blood-group systems and ABH secretion in Mongolian, Korean, and Zhuang nationalities in China

Among different blood-group systems investigated here, the distribution of the ABO system varies most of all, followed by MNSs and P. Although there are differences in ABH secretion in the different populations, no striking regularity has been found. No significant difference has been found in the distribution of the blood-group systems Rhesus, Diego, Duffy, Kell and Kidd in these Chinese populations: the Rh (-) rate is less than 1%, the frequency of Dia is about 0.04, the frequency of Fya is rather high, the frequency of K extremely low and Jka is about 0.4. In the three nationalities under study, Mongolians are characterized by a high frequency of IB, M higher than 0.5 and a relatively high frequency of P1. Koreans are characterized by a high frequency of IA, slightly more M than N and rather high CDE in the Rh system. The peculiarities of the Zhuangs are a rather high frequency of IO and M and the lowest frequency of P1.

Population genetic studies in three Chinese minorities

Three minority ethnic groups from China (Mongolians, Koreans, Zhuang) were examined with respect to the genetic markers GLO, GPT, ACP, ESD, 6-PGD, PGM1 subtypes, C3, and TF. Significant variations were noted for the gene frequencies of GLO, GPT, ESD, sub PGM1 between Zhuang and Mongolians; for GPT, ACP, ESD, sub PGM1 between Zhuang and Koreans; and for GLO between Mongolians and Koreans.

Prevalence of primary adult lactose malabsorption in three populations of northern China

Lactose absorption capacity was examined in 641 apparently healthy adolescents and adults (447 males and 194 females with an average age of 22.9 years and an age range of 16-46 years) using a field version of the lactose tolerance test with breath hydrogen determination. In the total sample, 89 lactose absorbers and 552 lactose malabsorbers were identified. Lactose malabsorption was most frequent in a subgroup of Han (Chinese) from northeastern China (229 of 248 subjects, 92.3%). Among 198 Mongols from Inner Mongolia, there were 174 lactose malabsorbers (87.9%). The frequency of lactose malabsorption was lowest in a group of Kazakhs, traditional herders from the northwestern region of Xinjiang (149 of 195 subjects, 76.4%). Reported symptoms of lactose intolerance were significantly more frequent in lactose malabsorbers. The findings in northern Han are similar to the reported lactose malabsorption frequency in southern (mainly overseas) Chinese, and correspond with the absence of animal milk from traditional Chinese diets. The relatively low prevalence of lactose malabsorption among the Kazakhs suggests that lactose persistence may be frequent in herding pastoralist populations of southwest Asia.