Volume 100  ·   Issue 03  ·  1987

Of 105 employees investigated, 53 (50.5%) cases of occupational contact dermatitis were observed. Most of the patients work at nitrition-condensation (NC) and packing sections. The clinical feature was the same as non occupational contact dermatitis. The results of the survey and patch tests on human show ed that the p-nitri-dimethylaniline hydrochloride (p-NDMAH), sodium nitrite (SN) and the mechanical irritation of vanillin dust were attributable factors for the dermatitis at the NC and the packing sections. Guinea pig tests showed that p-NDMAH and SN were the skin sensitizers. The former was also a skin irritant at >10 concentration. Vanillions was neither irritant nor sensitizer. Cross-sensitization exists between SN and p-NDMAH. It appears that nitroso group (-NO) plays a major role in inducing sensitization of p-NDMAH and SN.

Six selected Chinese families which had HLA-B16 related specificities B38, B39, Bw67 and ST-16 were typed using 9th International Histocompatibility Workshop sera to identify the relationship between the specificities. The results clearly show the existence of ST-16 in this Chinese population.

Polysaccharic acid salt, a component derived from Drynaria fortunei (Kunze) J, Sm, was reported. Animal experiment with rabbits showed that it is effective in preventing hypercholesterolemia and atherosclerosis.

Tissue typing was performed on lymphocytes of 74 unrelated patients and 12 families with multiple affected siblings. HLA-B13, Aw19, B17 (Bw57), Cwl, DR1 were found increased. The analysis of haplotype showed that one or two haplotype sharing among affected siblings occurred more frequently than expected (p<0.0001). The result of lods score for 4 families was 1.940. These findings suggest that there may be at least one disease gene linked with MHC involved in this disease.

86 patients with carcinoma of the lip were admitted to our hospital from March 1964 to December 1980. 63 (73%) were male and 23 female, the sex ratio being 2.7:1. The majority (74%) of the lesions were located on the lower lip, only 24% on the upper lip. 72 (84%) cases were squamous cell carcinoma while 9 (11%) were basal cell carcinoma in nature. There was one each of cylindroma, papilloma and leukoplakia with malignant change. Only one case of basal cell carcinoma was treated by radiotherapy and the rest by surgery. 64 cases had been followed for more than 5 years, yielding a 5-year survival rate of 72% (46/64).

A. dirus were reared by natural mating successively in large and small cages. The natural mating rate of the large cage colony reached 68% at the 14th generation and that of the small cage colony was 69%. This stabilized around 80% in the large cage colony and 60% in the small cage colony. The mosquitoes propagated continuously for 52 generations in the large cage colony and 38 generations in the small cage colony as of this writing. A sex ratio of 1:1.5 (female: male) is the best proportion for natural mating. Mating took place at least 48 hours after emergence and might continue for 21 days. Egg laying might continue for 51-61 days with an average number of 127.25 eggs deposited per female. There were two peaks of egg laying in each 24 hour period, the main peak occurred at 16:00-22:00 and the second peak at 2:00-4:00. When the eggs were stored at room temperature (13-20C) for 20 days the egg hatch rate was 72.7%.

The bilirubin in the gall stones is identified chemically and by infrared spectroscopy and gel electrophoresis as a polymer in structure. Its precipitation is closely related to the activity of β-glucuronidase, yet it is not the sole factor in conjugated bilirubin hydrolysis resulting in bilirubin precipitation. The quantitative determination of hexoamine with modified Boas-Morgan method shows glycoprotein suggesting that the greater the amount of glycoprotein in the bile, the stronger the lithogenicity. Atomic emission and absorption spectroscopy analysis lead us to believe that any elements appearing in the plasma should also be found in the bile or gallstone. The precipitation of solid substances in bile is strongly influenced by the alteration of Ca++ concentration, therefore the metal ions play an essential role in the formation of socalled insoluble components of the pigment gallstone. Dissolution tests reveal that increase of bile salt or glucuronic acid concentration in bile can reduce bilirubin precipitation. Chelating agents deprive the metal ions of the stone, leading to breakage and partial dissolution of the stone. CDTA may be a promising drug for dissolution of pigment gallstones.

A combination of levonorgestrel 0.15mg and ethinyl estradiol 0.03mg, an ultra-low dose oral contraceptive in pellet form, was tried out in 9 Beijing clinics. A total of 1,035 healthy women of reproductive age participated in 9,413 cycles of treatment. Only one pregnancy was attributed to medication failure which resulted in a corrected Pearl index of 0.13/100 women-year. The incidence of breakthrough bleeding and amenorrhea was 0.12% and 0.05% respectively. Using the life-table method, the net cumulative rate of termination due to medical-related reasons at one year was only 5.93/100 women. The incidence of side effects was low. The most frequent complaints were nausea and drowsiness, which reduced with the increase of treatment cycles. Some metabolic changes were studied. In comparison with other OCs used in China, this formula has the advantages of ultra-low-dose steroids with higher contraceptive efficacy, better cycle control and fewer side effects.

This article reports the cyclic AMP and cyclic GMP content of psoriatic epidermis and dermis and compares them with those of normal human skin. Cyclic AMP content of involved and uninvolved epidermis of psoriatic patients were found to be significantly decreased by 41% and 46% respectively (DNA data basis) as compared with normal human skin. But cyclic AMP content of psoriatic dermis was increased by 103% (wet weight), as compared to uninvolved and normal human dermis. Cyclic GMP content of psoriatic epidermis was significantly increased by 124% and 150% (wet weight) as com pared with uninvolved and normal human epidermis. These changes may play an important role in causing psoriatic lesions.

To examine the relative importance of serum thyroxine (T4), free thyroxine (fT4) and triiodothyronine (T3) in monitoring adequate T4 dose in patients on T4-replacement therapy, the effect of T4 dose on total T4, fT4 and T3, basal thyroid stimulating hormone (TSH) and TSH-response to thyrotropin releasing hormone (TRH) were investigated in 33 patients taking T4 doses of 50-200μg/day. The T4-treated patients had highly elevated mean T4 (total and free) and lower basal TSH levels compared to the mean values in normal subjects. But serum T3 was not significantly different. The patients on T4 doses greater than 150μg/day frequently had more suppressed TSH response to TRH than those on T4 doses less than 150µg/day. Total T4 and fT4, but not serum T3 levels, cerrelated significantly with T4 dosage. Changes in T4 dosage led to concomitant changes in total T4 and fT4 and inverse changes in TSH-response to TRH. The study also revealed a high incidence (33%) of elevated serum fT4 (hyperthyroxinemia) during therapy. The hyperthyroxinemic group was characterised by clevated serum T4 (total and free), T3 and T4 dose, and suppressed TSH-response to TRH compared to the T4-treated group with normal serum T4 levels. These findings may be indicative of excessive T4 treatment in these patients and suggest serum T4 may be more useful than T3 in monitoring T4 dosage in T4-replacement therapy. The discrepancy between normal serum T4 levels and TSH-response to TRH may reflect heterogeneity in returning normal function of the pituitary-thyroid axis. Clearly, measurement of TSH or TRH test can not be used alone in assessing thyroid status in these patients, particularly when serum T4 is in normal range.