[Study on the antitumor activity of CBMC activated by IL-12 alone or in combination with IL-2]

OBJECTIVE

To investigate the efficacy of cord blood mononuclear cells (CBMC) activated by interleukin-12 (IL-12) alone or in combination with interleukin-2 (IL-2) in tumor cells.

METHODS

The cytotoxicity of CBMC and peripheral blood mononuclear cells (PBMC) activated by IL-12 and/or IL-2 was measured with (3)H-TdR release assay, and the morphological change of K562 cells incubated with activated CBMC was observed.

RESULTS

(1) CBMC activated by 10 IU/ml IL-12 produced significant cytotoxic activities which were (27.23 +/- 4.92)% and (29.12 +/- 3.46)% against K562 and Raji cells, respectively; moreover, 10 IU/ml IL-12 could be synergized with the same dose of IL-2 in enhancing the cytotoxicities which were (47.60 +/- 4.60)% and (38.69 +/- 4.86)% against the two target cells, respectively. (2) Short-term incubation with IL-12 activated CBMC increased the cytotoxicity to K562 cells, and long-term incubation increased the cytotoxicity to Raji cells. (3) No NK lytic activity of CBMC could be detected before cytokines stimulation. After stimulated by 10 IU/ml IL-12, NK lytic activity of CBMC was similar to that of PBMC. (4) K562 cells demonstrated obvious apoptosis after cultured with activated CBMC.

CONCLUSION

CBMC activated by IL-12 had evident antitumor activity, which was further increased when IL-12 in combination with IL-2. These results showed the potential value to improve the graft-versus-leukemia (GVL) response after cord blood progenitor cell transplantation.

[Mapping the gene responsible for Smith-Fineman-Myers syndrome to Xq25]

OBJECTIVE

To map and eventually identify the gene responsible for Smith-Fineman-Myers syndrome.

METHODS

The short tandem repeat markers(STRs) distributed on X chromosome at 8-10cM interval were used in the initial mapping to look for the candidate region for Smith-Fineman-Myers syndrome locus and the linked marker. The additional STRs flanking the linked marker were tested to confirm the candidate region and decide the interval of disease gene.

RESULTS

Thirteen DNA samples from a Chinese family with Smith-Fineman-Myers syndrome were genotyped using 20 polymorphic STRs which cover the whole X chromosome. Of 20 STRs, DXS1001 on Xq25 suggested linkage and yielded a lod score of 3.01 at straight theta = 0 additional STRs flanking DXS1001 were tested. Fourteen polymorphic STRs out of 27 confirmed that Smith-Fineman-Myers syndrome locus is linked to several markers on Xq25. Haplotype analysis placed the disease locus within a 14.6cM interval bounded by DXS8064 and DXS8050.

CONCLUSION

The gene responsible for Smith-Fineman-Myers syndrome is mapped to a 14.6cM interval between DXS8064 and DXS8050 on Xq25. This result will be helpful for the identification of disease gene.

Mitotic recombination produces the majority of recessive fibroblast variants in heterozygous mice

Mice heterozygous at Aprt (adenine phosphoribosyltransferase) were used as a model to study in vivo loss of heterozygosity (LOH) in normal fibroblasts. Somatic cell variants that exhibited functional loss of the wild-type Aprt in vivo were recovered as APRT-deficient cell colonies after culturing in selection medium containing 2, 6-diaminopurine (DAP), an adenine analog that is toxic only to cells with APRT enzyme activity. DAP-resistant (DAP(r)) fibroblast variants were recovered at a median frequency of 12 x 10(-5) from individual ears from progeny of crosses between mouse strains 129/Sv and C3H/HeJ. The frequency of DAP(r) variants varied greatly among individual ears, suggesting that they preexisted in vivo and arose at various times during development. Polymorphic molecular markers and a cytological marker on the centromere of chromosome 8 made it possible to discriminate between each of six possible mechanistic pathways of LOH. The majority (about 80%) of the DAP(r) variants were a consequence of mitotic recombination. The prevalence of mitotic recombination in regions proximal to Aprt did not correlate with meiotic map distances. In particular, there was a higher than expected frequency of crossovers within the interval 59 cM to 67 cM. The high spontaneous frequency of Aprt LOH, mediated primarily by mitotic recombination, is fully consistent with our previous results with human peripheral T cells from individuals known to be heterozygous at APRT. Thus, this Aprt heterozygote mouse is a valid model for studying somatic mutagenesis and mitotic recombination in vivo.

Clinical analysis of 69 patients with familial benign chronic pemphigus

OBJECTIVE

To analyze the clinical feature, efficacy of treatment and prognosis in familial benign chronic pemphigus (FBCP).

METHODS

Sixty-nine cases of FBCP were retrospectively analyzed.

RESULTS

The ratio of male to female is 3.93:1 in 69 patients (55 males, 14 females). The mean age at the onset was 29.09 years (3-60 years). There was familial history in 27 families in all of the cases. The lesion usually involved in genital area, neck, axillae and popliteal fossa. Erythemas and vesicles on the soles were seen only in 1 case. Histopathologically 44 cases had special features of FBCP, and immunopathologically 8 cases were direct immunofluorescence (DIF) negative, in which one case had C3 linear deposition along dermoepidermal junction. The combined regimen was more effective. The low-dose X-ray could improve the effect.

CONCLUSION

The disease is transmitted as an irregular autosomal dominant trait. The condition in males is more frequent than that in females, probably owing to the different level of female hormone in both sexes. Our patients have the same clinical features as those reported in the literature, but the erythema, vesicle lesions on sole have not been documented in the literature. The combined therapy should be adopted in this condition.

Formation of single- and double-strand breaks of pBR322 plasmid irradiated in the presence of scavengers

By the method of gel electrophoresis, radiation-induced DNA single- and double-strand breaks (SSB, DSB) were studied with a model system of pBR322 solution in vitro in the presence of 'OH radical scavengers, mannitol and TE (10(-2) mol dm(-3) Tris and 10(-3) mol dm(-3) ethylene diamine tetra-acetic acid). Experiments showed that SSB resulted from one-hit events of radiation energy deposition and DSB resulted from both one-hit and two-hit energy deposition events and so were distinguished into two classes of alphaDSB and betaDSB. Moreover, alpha/beta, where alpha is the number of DSB per unit dose induced in one irradiation event and beta the number of DSB per unit squared dose induced by the combination of two independent SSB, was related to the scavenging capacity, sigma, and for sigma > 10(8) s(-1), alphaDSB predominate over DSB. On the other hand, if sigma<2x10(8)s(-1), the measured G(alphaDSB) decreased in parallel with G(SSB), i.e., G(alphaDSB)/G(SSB) was a constant. When sigma>2x10(8) s(-1). G(alphaDSB) decreased slightly so that the ratio of alphaDSB to SSB evidently increased. Therefore, alphaDSB could be induced by the radical transfer mechanism for sigma<2x10(8) s(-1) and contrarily produced by the local multiply damaged sites (LMDS) mechanism for sigma larger than this value. In addition, the distance for two independent complementary SSB forming a DSB was deduced, but no apparent variation of it was found in the wide sigma range from approximately 10(5) to approximately 10(9) s(-)1, which shows that the DNA steric structure was not influenced by mannitol.

[Perioperative management of open-chest surgery for cancer patients in advanced stage in aged and with respiratory insufficiency]

For patients with chest cancer who are in advanced stage, aged, or/and with respiratory insufficiency, the key to the success of open-chest surgery is intensive management of the respiratory tract and proper treatment of complications in perioperative period. From May 1984 to November 1995, 1661 patients with esophageal and lung cancer underwent thoracotomy in our hospital. 198 of the 1661 patients fit in with the standards of advanced, aged or respiratory insufficiency. The patients were aged over 70 years, with the length of esophageal cancer over 10 cm and, the MVV less than 50% (least 24.3%). The results the patients were satisfactory because a series of the effective measures of perioperative management were tahen. They incladed thyrocrico-puncture and use of a fine tube through which drugs were injected to irritate cough sputum out; examination and suction with bronchofiberoscope; tracheo-bronchial lavage through bronchofiberoscope with antibiotics solution; and tracheotomy using ventilator appropriately. Perioperative intensive management is very important for extending operation indication and tiding over critical period.

High frequency in vivo loss of heterozygosity is primarily a consequence of mitotic recombination

We have used the adenine phosphoribosyltransferase gene (APRT; 16q24) to investigate the mechanisms of loss of heterozygosity (LOH) in normal human somatic cells in vivo. APRT-deficient (APRT-/-, APRT-/0) T lymphocytes from the peripheral blood of four obligate APRT heterozygotes (APRT+/-) with characterized germ-line mutations were selected in medium containing 100 microM 2,6-diaminopurine. A total of 80 2,6-diaminopurine-resistant T-cell clones from 2 of the heterozygotes were analyzed for this study. The presence or absence of LOH of proximal linked microsatellite repeat markers was used to divide the clones into two groups: (a) those in which LOH was likely due to localized changes in APRT (e.g., point mutations); and (b) those with LOH at additional loci. A total of 61 clones (76%) exhibited LOH of linked microsatellite repeat markers at different locations on 16q, which extended from the smallest measured region (<5.5 cM) to the entire 16q arm. The remaining 19 clones (24%) had point mutations in APRT or other relatively minor alterations. Ten clones with LOH encompassing different regions of 16q were examined by conventional cytogenetics and by fluorescence in situ hybridization using an APRT cosmid probe. All clones exhibited a normal diploid karyotype, and nine exhibited two copies of APRT. The one clone that was hemizygous for APRT had the smallest observed region of LOH in clones from that individual. These results indicate that mitotic recombination and, to a much lesser extent, deletion may be the primary mechanisms for the relatively high frequency of in vivo LOH observed in normal human T cells. Because LOH leads to the expression of recessive tumor suppressor genes in many cancers, these data have significant implications for the role of LOH in the early stages of tumor development, especially in breast cancer.

Localization of group IIc low molecular weight phospholipase A2 mRNA to meiotic cells in the mouse

We use in situ hybridization to demonstrate that the testicular expression of a novel, mouse, low molecular weight phospholipase A2 (PLA2 Group IIc) mRNA is specific to cells undergoing meiosis. A complete cDNA (1421 bp) encoding the mouse Pla2g2c gene was generated with reverse transcription-PCR (RT-PCR) and 5' and 3' RACE (rapid amplification of cDNA ends) RT-PCR, and its nucleotide sequence was determined. Northern blots of RNA from different tissues revealed a single 1.6 kb transcript only in testis. In situ hybridization indicated that this mouse gene is transcribed mainly in pachytene spermatocytes, secondary spermatocytes, and round spermatids. Expression of the gene is seen in all stages of the seminiferous epithelium, especially in stages VI-VII.

Loss of heterozygosity analysis in a human fibrosarcoma cell line

Loss of heterozygosity (LOH) is an important event in tumor formation. We have used polymorphic microsatellite repeat markers to identify and characterize LOH in spontaneous mutants of a human cell line, MR12-1, that is heterozygous for the adenine phosphoribosyltransferase gene (APRT+/-) located on chromosome 16q24.3. Initially, clones without extensive LOH (which are likely derived as a consequence of intragenic point mutations) and clones with multilocus LOH (which are likely due to major chromosome alterations) were identified. Clones with major regions of LOH were further characterized by assaying additional informative microsatellite markers. Analysis of 20 spontaneously-arising, independent APRT-/- clones from MR12-1 demonstrated that nine of the mutants retained both copies of APRT and 11 had undergone multilocus genetic alterations. The nature of LOH in four of the latter clones has been examined in detail by karyotype and fluorescence in situ hybridization analysis (Shao et al., 1996). These data demonstrate that LOH of chromosome 16 may be due to mitotic recombination, interstitial or partial deletion, or to more complex mechanisms. LOH in these clones may be a consequence of events similar to those observed in many tumors.

Sexually transmitted disease control in China (1949-1994)

This paper summarizes the historical experiences in venereal disease control in China during the 1950s. Venereal diseases had been all but eliminated in the whole country till 1964. However, along with the implementation of open-door policy and economic reform in the 1980s, the social environment was changed to a great extent in this country. Sexually transmitted diseases (STDs) were re-introduced in the Chinese mainland and new foci of infection established themselves in some cities. During the recent 8 years the national STD case-reporting and sentinel surveillance systems have been set up. The results of surveillance show that the annual incidence of STD has been on the increase. The existing factors associated with the increasing incidence of STD mainly are; population movement, increasing affluence in a part of population, the availability of multiple sexual partners (including the prostitution) and asymptomatic STD increased. Finally, the strategies for STD control are discussed in detail.

APRT: a versatile in vivo resident reporter of local mutation and loss of heterozygosity

We describe an in vivo mutagenesis model that utilizes reverse mutation and forward mutation at the endogenous Aprt locus. Reverse mutation provides an in situ method for detecting environments or agents that cause point mutations. Forward mutation detects large chromosomal events, including mitotic recombination, chromosome loss, and large multilocus deletion, all of which can lead to loss of heterozygosity. Detection of reverse mutation in vivo is based on the differential capacity of Aprt and Aprt cells to sequester radiolabeled adenine by catalyzing its conversion to adenosine monophosphate with subsequent incorporation into nucleic acids. Cells lacking APRT activity cannot accumulate exogenously administered, tagged adenine, whereas Aprt+ cells can and will thereby become marked. Thus, genetically modified mice with mutant but revertible Aprt alleles should be a useful vehicle for in situ detection of mutagenic activity in the whole animal. the feasibility of this model has been illustrated, first, by showing that APRT-deficient mice are viable and, second, by demonstrating that the minority of Aprt+ cells within a chimeric tumor growing in an Aprt+ mouse can be selectively labeled following IP injection of [14C]-adenine and can be identified by autoradiography. Forward mutation, detected by growth in selective medium of primary cells derived from Aprt+/- heterozygous mice, provides on independent estimate of in vivo mutation frequency. The frequency with which Aprt colonies arise provides a measure of the frequency of Aprt(-)-negative cells in the tissue at that point in time. Culture of skin fibroblasts in 2,6-diaminopurine (DAP) produced Aprt+ colonies with a frequency of about 10(-4). This frequency is similar to that found for human T lymphocytes from individuals heterozygous at the Aprt locus. In both cases, the majority of mutagenic events involved allele loss. Polymerase chain reaction with linked polymorphic microsatellites on mouse chromosome 8 demonstrated that allele loss was mediated mostly by mitotic recombination, as was the case for human T lymphocytes. The high frequency of mitotic recombination and allele loss at a neutral locus has significant implications for the process of tumorigenesis and argues that spontaneous or induced mitotic recombination may play a causal role in the progression to cancer.

Complex chromosomal mechanisms lead to APRT loss of heterozygosity in heteroploid cells

Loss of the wild-type allele of a tumor suppressor gene, or loss of heterozygosity (LOH), is one of the most important mechanisms of carcinogenesis. Adenine phosphoribosyltransferase (APRT) has been used as a surrogate marker for tumor suppressor genes. We have previously shown that APRT deficiency in an APRT heterozygous human cell line, MR12-1, was predominantly caused by the loss of the remaining wild-type allele. Here we report the characterization of the chromosomal pathways leading to LOH in four clones derived from this heteroploid cell line. We performed karyotype analysis, chromosome 16-specific painting, and fluorescence in situ hybridization with an APRT-containing cosmid on these clones and their heteroploid parental cells. Our findings suggest that LOH occurs in tetraploid as well as diploid cells, and that diploid cells with LOH may undergo endoreduplication to attain tetraploidy. Our results also suggest that, in addition to LOH being caused by a single event (such as mitotic recombination or deletion), LOH may be caused by a combination of sequential events, such as mitotic recombination or translocation followed by chromosome loss. The instability of the genomes of the parental cells may have provided a greater diversity of options for genetic evolution. Similar karyotypic evolution may occur at late stages of carcinogenesis in vivo.

[The application of the pattern visual-evoked potential in the diagnosis and treatment of amblyopia]

PURPOSE

To research into the value of the application in the diagnosis and treatment of amblyopia, and to discuss the mechanism of amblyopia.

METHODS

The subjects were divided into three groups: 108 amblyopia eyes; 180 normal eyes and 26 amblyopia eyes during the treatment with Madopar. PVEP was observed with black-white checks pattern-reversal stimulation at several spatial frequencies (30', 60', 90').

RESULTS

P1 latency of the amblyopia eyes prolongs at the high frequency (30' angle of view), in which the occurrence rate of abnormal PVEP is 68.5%. Through detecting PVEP during the treatment of amblyopia with Madopar, we found P1 latency shortened and amplitude increased (P < 0.05).

CONCLUSION

It is better to use P1 latency to observe the visual function of patients with amslyopia with stimulation at 30' angle of view. PVEP is an important objective index in diagnosis and evaluating the curative effect of amblyopia.

Genetic study of indirect inguinal hernia

We performed a genetic analysis of 280 families with congenital indirect inguinal hernia ascertained in Shandong province. The multifactorial threshold model and segregation analysis were applied to these families to investigate the mode of inheritance of congenital indirect inguinal hernia. Our results indicate that congenital indirect inguinal hernia is not compatible with a multifactorial threshold model, and the frequent vertical transmission and high segregation ratio suggest autosomal dominant inheritance with incomplete penetrance and sex influence. Through further pedigree analysis of the multiple case families with at least two closely related affected members, we noted preferential paternal transmission of the disease gene, which might suggest the role of genomic imprinting in the aetiology of this condition.

Prevalence and epidemiologic correlates of sexually transmitted Chlamydia trachomatis infection in a selected population

The incidence of Chlamydia trachomatis genitourinary infection was found by enzyme immunoassay antigen detection to be 10.0% in patients attending a sexually transmitted disease (STD) clinic, 3.0% in clients visiting an obstetrics-gynecology clinic, 20.8% in female prostitutes, and 1.3% in sexually active men. Predisposing factors for chlamydial infection were young age, multiple sexual partners, history of STDs, and coinfection with other STDs. Abnormal vaginal discharge and cervices in women, but not urethral manifestations in men, were significantly associated with chlamydial infection. Urethral gram stain had a certain value in identifying men infected with C. trachomatis.

STD epidemiologic analysis at national surveillance spots in the period 1987-1990

This article summarizes surveillance data of STDs at 16 urban monitoring centers in 1987-1990. During the four year period, 125,493 STD cases were reported. The average annual incidence was 77.80/100,000. Because the rate of increase in females (65.85% per year) was greater than that in males (36.81% per year), the male-to-female ratio fell from 2.39:1 (1987) to 1.34:1 (1990). The number of STD cases reported from all centers tended to increase, and the overall rate of increase was 46.61% per year. The major disease was gonorrhea, with a constituent ratio of 59.22% (1990). However, condyloma acuminatum and nongonococcal urethritis had greater rates of increase (105.03% and 85.14% per year, respectively). The 20-39 year age group accounted for 82.10% of total cases, for STD patients were mostly in the sexually active population. The STD incidence among self-employed businessmen (1206.06/100,000, in 1990) was highest among professional populations. According to analysis of different regions, STD incidence was highest in the southern cities (203.00/100,000, 1990). The greatest rate of increase of STDs was in Yangtze River Valley cities, where the average annual rate of increase was 71.41%.

[Ca2+ channel blocking effect of panaxadiol saponins and panaxatriol saponins of cultured cardiac cells]

It was found that PDS and PTS decreased the action potential parameters of the cultured myocardiocytes in a dosage-dependent way. The effects of PDS 1000 micrograms/ml, PTS 200 micrograms/ml were in correspondence with the known Ca2+ channel blocker Mn2+ 0.05 micrograms/ml. Washing out, administration of epinephrine 10 micrograms/ml or Ca2+ 80 micrograms/ml were able to reverse the action potential from inhibition. The above results indicate that both PDS and PTS have Ca2+ channel blockade action.