Natural history of Crohn's disease in patients who underwent intentional restorative proctocolectomy with ileal pouch-anal anastomosis

BACKGROUND

Crohn's disease is generally considered a relative contraindication for restorative proctocolectomy with ileal pouch anastomosis (IPAA). The natural history of IPAA in these patients has not well been defined.

AIM

To evaluate the natural history of IPAA in patients with a well-defined preoperative Crohn's disease.

METHODS

All patients from the Pouchitis Clinic who had a preoperative diagnosis of Crohn's disease were screened and 11 patients met the inclusion criteria. The control group (with a 1:4 ratio) consisted of IPAA patients with a preoperative diagnosis of UC.

RESULTS

During the follow-up period of 5.0 years, 7 of 11 (63.6%) with a preoperative diagnosis of Crohn's disease developed Crohn's disease of the pouch. Crohn's disease of the pouch developed 0.2-15 years after ileostomy closure. The remaining four patients with a preoperative diagnosis of Crohn's disease did not demonstrate signs of Crohn's disease in 2, 11, 11 and 24 years after pouch surgery, respectively.

CONCLUSIONS

Post-operative development of Crohn's disease of the pouch was common in patients with a preoperative diagnosis of Crohn's disease who underwent IPAA. Long-term medical therapy was often required. Large multi-centre studies are warranted to delineate further the natural history of the disease, before Crohn's disease is considered an indication for IPAA.

Pyloric gland metaplasia and pouchitis in patients with ileal pouch-anal anastomoses

BACKGROUND

Diagnosis and management of chronic antibiotic-refractory pouchitis and Crohn's disease of the pouch can be challenging. Pyloric gland metaplasia is a histological feature indicative of chronic mucosal inflammation. Its value in diagnosis and prognosis of pouch disorders has not been investigated.

AIM

To assess the prevalence, diagnostic and prognostic value, and risk factors of pyloric gland metaplasia in pouch patients.

METHODS

Patients were identified from our prospectively maintained Pouchitis Database. Pouch biopsy specimens were re-reviewed for pyloric gland metaplasia and other histological features. Two cohorts of patients were studied: a historical cohort (n = 111) and the second, a validation cohort (n = 100). Univariate and multivariate analyses were performed to assess risk factors for pyloric gland metaplasia.

RESULTS

The prevalence of pyloric gland metaplasia in the historical cohort and validation cohort was 45 (40.1%) and 24 (24.0%), respectively. The sensitivity and specificity of pyloric gland metaplasia for the diagnosis of chronic antibiotic-refractory pouchitis or Crohn's disease were 70.7% and 92.5%, respectively, for the first cohort and 39.0% and 86.4%, respectively, for the 2nd validation cohort. In multivariate analysis of the first cohort, patients with refractory pouchitis or Crohn's disease were 28 times (95% CI, 7.3-107.1) more likely to have pyloric gland metaplasia than those with a normal pouch or irritable pouch syndrome. The factor of refractory pouchitis or Crohn's disease remained in the model for the 2nd validation cohort with odds ratio of 4.58 (95% CI, 1.6-13.4).

CONCLUSIONS

Pyloric gland metaplasia is associated with diagnosis of chronic antibiotic-refractory pouchitis or Crohn's disease of the pouch and appears to be a specific marker for both disease entities.

Endoscopic treatment for pill bezoars after continent ileostomy

Difficulty intubation is the most common long-term complication after continent ileostomy, which can be associated with nipple valve slippage, parastomal hernia, stenosis. Diagnosis and management of a patient with nipple valve stricture and partial bowel obstruction associated with dietary supplement retention in the pouch reservoir is described. A 50-year-old female patient with ulcerative colitis and a 15-year history of continent ileostomy after total proctocolectomy reported 5-week symptoms of abdominal pain and difficulty in intubating the pouch. Pill bezoar composed of dietary supplement was found in diagnostic pouch endoscopy. Therapeutic pouch endoscopy was performed with balloon dilation of a nipple valve stenosis and retrieval of 224 dietary supplement tablets. Pill bezoar in the pouch is rare. However, patients with continent ileostomy should be advised to avoid taking hard-to-dissolve foods and medications.

101 DEVELOPMENTAL ARREST AND CYTOSKELETAL ANOMALIES OF RAT EMBRYOS RECONSTRUCTED BY SOMATIC CELL NUCLEAR TRANSFER

Many factors influence success rates in animal cloning by somatic cell nuclear transfer (SCNT), including cell cycle stage of the donor cells and recipient oocyte, the procedure of micromanipulation, and the activation protocol. It has been reported that the development of rat embryos is inhibited at the 2-cell stage during in vitro culture and that microtubule (MT) distribution is involved in the developmental arrest. This study was conducted to determine the effects of oocyte activation methods and the cell cycle coordination for cloning rats from fetal fibroblasts (FF). Recipient oocytes were activated with cycloheximide, 6-dimethylaminopurine, and roscovitine and used either before (metaphase-II, MII) or after (telophase-II, TII) activation for fusion with FF at the G0/G1-phase, metaphase, and S/G2-phase. Moreover, enucleated zygotic and parthenogenetic ooplasts were used for serial cloning with pronuclear and 2-cell-stage blastomeres derived from SCNT. There was no significant difference in the first cleavage rate in the 3 activation groups after SCNT. Metaphase donor cells (85.2%) had a significantly higher cleavage rate than G0/G1-phase FF with MII oocytes (70.4%) and G2-phase FF with TII oocytes (72.2%). However, reconstructed embryos were unable to develop beyond the 2-cell stage either in vitro or in vivo. Moreover, serial cloning with zygotic and parthenogenetic recipients was also unable to overcome the developmental arrest at the 2-cell-stage. To assess the cytoskeleton after SCNT, reconstructed 2-cell-stage embryos were harvested at different times after cleavage for immunostaining (anti alpha-tubulin) and mRNA abundance (beta-actin and alpha-tubulin). Reconstructed 2-cell embryos showed much thicker fibrous or disconnected MT distribution concomitant with a reduction in cytoskeletal transcripts at the late 2-cell stage. In summary, our results indicate that the developmental arrest of rat SCNT embryos was a result of abnormal MT distribution caused by improper transcription of cytoskeleton genes; however, further studies are needed to understand the early developmental block of rat SCNT-derived embryos.

The clinical spectrum of Bruton's agammaglobulinemia

X-linked, or Bruton's, agammaglobulinemia (XLA) was described in 1952 as the congenital inability to form antibodies. Patients were typically infants or young children with recurrent, severe bacterial infections. Other, milder cases of hypogammaglobulinemia were considered "acquired," and often presented later in life. Since the discovery of the defective gene in XLA in 1993, it has been shown that a significant number of male patients with sporadic or acquired hypogammaglobulinemia actually have XLA. We present here a case of atypical XLA and discuss similar cases in the literature. We conclude that any male with hypogammaglobulinemia, regardless of age of presentation, might have XLA. Males with low B-cell numbers are particularly likely to have XLA and should have Bruton's tyrosine kinase levels assessed.

[The hygienic examination and quality research of Chinese crude drug scorpion]

We selected the method of hygienic test to determinate the infection of colibacilli, salmonelli, mixed bacteria, mould fungus and yeasts on Chinese crude drug scorpion from 29 commerical samples in different storaged period, habitats and commerical standard. The results showed there were not colibacilli and salmonelli in all 29 samples, but infectious mixed bacteria rate is 100%, which is 2.1 times more than salty scorpion in 29 tested samples, and the infectious fungi rate is 72.4%. The fungi of salty scorpion is 15% more than fresh scorpion. The quantity of infected yeasts on salty scorpion is much more than scorpion. There are 4 species of fungi such as Alternaria neesex Wallroth, Aspergillus fumigatus Fresenius, Nocarcia sp. and Tricophyton violaceum Sabouraud. Because of infectious pathogenic bacteria rate is so high, we suggest to increase the item of hygienic test to control the quality of crude drug scorpion and strengthen the administration of commerical drugs, so as to reduce the contaminative condition.

[Surgical procedure of gynecologic malignances in patients over 70 years]

OBJECTIVE

To assess the viability of performing surgical procedure on gynecologic malignances patients over 70 years old.

METHODS

A retrospective study of all patients 70 years of age and older treated by surgical procedure for gynecologic malignances was performed between September 1, 1983, and June 30, 1999.

RESULTS

Fifty-seven patients were older than 70 years of age at the time of the diagnosis. Mean age of the patients was 73.5 years. In thirty-four patients a extensive surgical procedure was carried out, while in twenty-three patients a conservative surgery was done. Seventy-one percent of patients had one or more preexisting medical illnesses. Minor surgical morbidity occurred in 31.6% of the patients, while major surgical morbidity occurred in 10.5% of the patients. There were no differences in the type of surgical procedure, mean hospital stay, preexisting medical illness and postoperative complication between patients 70 to 75 and over age 75. The total major postoperative complications occurred in extensive surgical procedure group and postoperative mean stay was also significantly length.

CONCLUSIONS

The extensive surgical procedure is a safe treatment for elderly patients with gynecologic malignances. Careful preoperative assessment, monitoring, and meticulous postoperative care are vital to the success.

Maturation of the reconstructed oocytes by germinal vesicle transfer in rabbits and mice

The present study was designed to evaluate the feasibility of germinal vesicle (GV) transfer in rabbits and mice. The GV oocytes were collected from ovaries and cultured in 20 microg/mL 3-isobutyl-1-methylxanthin (IBMX) in TCM199 medium, which caused oocytes to shrink, enlarging the perivitelline space to facilitate the GV removal and transfer. Pairs of GV-cytoplast complexes were fused with electric pulses, and the fused, reconstructed oocytes were cultured in TCM199 for 24 h. Results are as follows: 1) The exposure time of rabbit GV oocytes to IBMX medium affected the success of GV removal. For oocytes cultured for 2 and 3 h in IBMX medium, removed rates were 56% and 44, respectively, significantly higher (P < 0.05) than removal rates of GV oocytes cultured for 1 and 4 h (27% and 27%, respectively); 2) There was no significant difference (P > 0.1) in fusion and maturation rates of rabbit reconstructed oocytes collected at 72 and 84 h after initiation of FSH injection to donors; 3) eCG in the maturation media improved development of rabbit-to-rabbit GV transferred oocytes but had no positive effect on mouse-to-rabbit GV transferred oocytes; 4) When mouse GV-karyoplasts were injected into enucleated rabbit oocytes, fusion rates of GV-karyoplasts measuring 40- to 50-microm and 80- to 90-microm in diameters obtained were 84% and 93%, respectively. The rates were significantly higher (P < 0.05) than fusion rates after transferring GV-karyoplasts measuring 30- to 35-microm in diameter (63%). The maturation rate (89%) of reconstructed oocytes composed of 80- to 90-microm mouse GV-karyoplasts and rabbit GV-enucleated cytoplasts was higher than that seen for oocytes composed of 40- to 50-microm (77%, P<0.05) or 30- to 35-microm (59%, P<0.01) mouse karyoplasts. Thirty-five of the 63 (56%) mature mouse-to-rabbit reconstructed oocytes had the normal complement of 20 chromosomes.

Pharmacokinetic profile of the anti-sickling hydroxyurea in wild-type and transgenic sickle cell mice

The pharmacokinetic profile of hydroxyurea (HU) was investigated by measuring the rate of drug disappearance from the plasma in wild-type and transgenic (Tg) sickle cell mice. The absorption and elimination processes of HU exhibited first-order kinetics after intraperitoneal administration of HU at 10, 50, 100 or 200 mg/kg body weight (BW). The dosage had a marked effect on the pharmacokinetics of HU in the Tg sickle cell mice. Although the area under the plasma concentration curve (AUC) increased in direct proportion with the HU dose in the wild-type mice, the AUC increased to a much greater extent at higher doses in the Tg sickle cell mice. In the Tg sickle cell mice, there was a considerable increase in the mean residence time (MRT) and a significant reduction in the apparent clearance (CL/F) at HU dose > or =100 mg/kg BW, when compared to the lower doses. At an HU dose of 200 mg/kg BW, the CL/F in the Tg sickle cell mice was reduced by about 50% of the value obtained at a dose of 10 mg/kg BW. This phenomenon was not noticeable in the wild-type mice. The MRT value in the wild-type mice at all doses was relatively constant. The steady-state distribution volume of HU in both the wild-type and Tg sickle cell mice was relatively constant at all doses of the drug. The AUC, CL/F, MRT, and terminal half-life values at any given HU dose showed significant differences between the wild-type and Tg sickle cell mice. Following intraperitoneal administration of HU at a dose of 10, 50, 100, or 200 mg/kg BW, the mean percentage of HU excreted in the urine of the wild-type and Tg sickle cell mice over 120 min was 84 +/- 6.4% and 50 +/- 8.2%, respectively, indicating a significant difference in the amount of HU excreted in urine in the two kinds of mice. The results obtained in this study may be useful in establishing an optimal dose of HU in the treatment and management of patients with sickle cell disease and other hemoglobinopathies.

Mutation analyses of 268 candidate genes in human tumor cell lines

We have performed a homozygous deletion screen on 268 candidate genes in 90 human tumor cell lines derived from multiple types of cancers. Most of the candidate genes investigated have been proposed to be involved in cellular processes that are germane to cancer progression, such as cell cycle control, genome maintenance, chromatin remodeling, cell adhesion, and apoptosis. We have detected novel homozygous deletions affecting four independent loci: Brahma-related gene (SMARCA4) on chromosome 19p in the TSU-Pr1 prostate and A427 lung carcinoma lines, Map Kinase Kinase 3 (MAP2K3) on 17q in the NCI-H774 lung tumor cell line, TMPRSS2 on 21q in the Bx PC-3 pancreatic carcinoma line, and Cadherin 6 (CDH6) on 5p in the SK-LU-1 lung carcinoma line. Subsequent analyses of the coding sequences of these four genes using cDNAs from a panel of tumor cell lines revealed multiple sequence variants. The results of this mutation study serve to demonstrate the feasibility of performing high-throughput screens of candidate genes in tumor cell lines to identify genes that may be targeted for mutation during the development of cancer.

Characteristics, diagnosis and treatment of hepatic metastasis of pure immature ovarian teratoma

OBJECTIVE

To analyze the characteristics of hepatic metastasis of pure immature ovarian teratoma and explore its proper diagnosis and treatment.

METHODS

Eighteen cases of hepatic metastasis of pure immature ovarian teratoma were included in this study. The clinical stage, operation, chemotherapy and histopathology of primary and secondary tumors as well as the data from long term follow-ups were analyzed retrospectively.

RESULTS

All of the hepatic metastatic tumors were located on the surface of the liver. 61.1% (11/18) of them were clinical stage III and 44.4% (8/18) were grade 1 at first operation. The hepatic metastatic rate was 16.7% (3/18) in the standard adjuvant chemotherapy group but increased markedly to 31.2% (15/48) in the irregular chemotherapy group. Auxiliary diagnostic methods could not indicate the correct results. The surgical resection rate of hepatic metastasis of pure immature ovarian teratoma was 94.4% (17/18). There were less complications in the group with tumor diameter less than 15 cm. The follow-up time ranged from 3 to 205 months with a mean of 20.9 months. The 3-year-survival rate was 77.8% (14/18), and mortality rate was 22.2%. The 5- and 10-year-survival rate was 55.6% (10/18) and 38.9% (7/18), respectively. The rate of loss in follow-up was 22.2% (4/18) and 38.9% (7/18), respectively, and one patient has survived for more than 17 years.

CONCLUSIONS

The hepatic metastatic rate of pure immature ovarian teratoma could be decreased using standard adjuvant chemotherapy. Suitable surgical treatment could reduce complications and improve the prognosis for patients.

Mouse-rabbit germinal vesicle transfer reveals that factors regulating oocyte meiotic progression are not species-specific in mammals

A series of experiments were designed to evaluate the meiotic competence of mouse oocyte germinal vesicle (GV) in rabbit ooplasm. In experiment 1, an isolated mouse GV was transferred into rabbit GV-stage cytoplast by electrofusion. It was shown that 71.8% and 63.3% of the reconstructed oocytes completed the first meiosis as indicated by the first polar body (PB1) emission when cultured in M199 and M199 + PMSG, respectively. Chromosomal analysis showed that 75% of matured oocytes contained the normal 20 mouse chromosomes. When mouse spermatozoa were microinjected into the cytoplasm of oocytes matured in M199 + PMSG and M199, as many as 59.4% and 48% finished the second meiosis as revealed by the second polar body (PB2) emission and a few fertilized eggs developed to the eight-cell stage. In experiment 2, a mouse GV was transferred into rabbit MII-stage cytoplast. Only 13.0-14.3% of the reconstructed oocytes underwent germinal vesicle breakdown (GVBD) and none proceeded past the MI stage. When two mouse GVs were transferred into an enucleated rabbit oocyte, only 8.7% went through GVBD. In experiment 3, a whole zona-free mouse GV oocyte was fused with a rabbit MII cytoplast. The GVBD rates were increased to 51.2% and 49.4% when cultured in M199 + PMSG and M199, respectively, but none reached the MII stage. In experiment 4, a mouse GV was transferred into a partial cytoplasm-removed rabbit MII oocyte in which the second meiotic apparatus was still present. GVBD occurred in nearly all the reconstructed oocytes when one or two GVs were transferred and two or three metaphase plates were observed in ooplasm after culturing in M199 + PMSG for 8 hr. These data suggest that cytoplasmic factors regulating the progression of the first and the second meioses are not species-specific in mammalian oocytes and that these factors are located in the meiotic apparatus and/or its surrounding cytoplasm at MII stage.

Sucrose pretreatment for enucleation: an efficient and non-damage method for removing the spindle of the mouse MII oocyte

Oocytes enucleated at metaphase II stage can support reprogramming of transferred nucleus and further developing to term. However, the first polar body in mice sometimes migrates away from the original place of expulsion, so the chromosomes of the oocyte will displace from the first polar body. Thus, it is not always possible to successfully enucleate according to the position of the first polar body. Here we use sucrose treatment to visualize metaphase spindle fibers and chromosomes with standard light microscopy. In the manipulation medium containing 3% sucrose, oocytes of poor quality become shrunken, deformed or fragmented, while oocytes of good quality in the same medium would show a swelling around the metaphase chromosomes and a transparent spindle area, shaped like "infinity" and "0". So it is easy to remove the well-distinguished spindle and chromosomes in oocytes of good quality. Re-examined by Hoechst 33342 stain under the UV light, the enucleation rate was 100%. There was no significant difference in IVF and cleavage rates between the sucrose treatment and the control group. In conclusion, this study demonstrated that 3% sucrose pretreatment can give a method for evaluating embryo quality and more importantly, it can, under a common microscope, allow the visualization of the spindle and chromosomes in oocytes of good quality and hence efficiently improve enucleation rate without any harm.

Treatment with NS3623, a novel Cl-conductance blocker, ameliorates erythrocyte dehydration in transgenic SAD mice: a possible new therapeutic approach for sickle cell disease

The dehydration of sickle red blood cells (RBCs) through the Ca-activated K channel depends on the parallel movement of Cl ions. To study whether Cl-conductance block might prevent dehydration of sickle RBCs, a novel Cl-conductance inhibitor (NS3623) was characterized in vitro using RBCs from healthy donors and sickle cell patients and in vivo using normal mice and a transgenic mouse model of sickle cell disease (SAD mice). In vitro, NS3623 reversibly blocked human RBC Cl-conductance (g(Cl)) with an IC(50) value of 210 nmol/L and a maximal block of 95%. In vivo, NS3623 inhibited RBC g(Cl) after oral administration to normal mice (ED(50) = 25 mg/kg). Although g(Cl), at a single dose of 100 mg/kg, was still 70% inhibited 5 hours after dosing, the inhibition disappeared after 24 hours. Repeated administration of 100 mg/kg twice a day for 10 days caused no adverse effects; therefore, this regimen was chosen as the highest dosing for the SAD mice. SAD mice were treated for 3 weeks with 2 daily administrations of 10, 35, and 100 mg/kg NS3623, respectively. The hematocrit increased, and the mean corpuscular hemoglobin concentration decreased in all groups with a concomitant increase in the intracellular cation content. A loss of the densest red cell population was observed in conjunction with a shift from a high proportion of sickled to well-hydrated discoid erythrocytes, with some echinocytes present at the highest dosage. These data indicate feasibility for the potential use of Cl-conductance blockers to treat human sickle cell disease.

Viable rabbits derived from reconstructed oocytes by germinal vesicle transfer after intracytoplasmic sperm injection (ICSI)

Abnormal oocyte spindle due to the improper function of ooplasm is associated with female infertility of advanced maternal age. A possible way to overcome this problem is to transfer an oocyte germinal vesicle (GV) which contains genetic materials of a patient with a history of poor embryo development to the cytoplast from a donor oocyte. Here we demonstrate that GV transfer is feasible using a rabbit model. When the GVs were transferred to auto- or hetero-cytoplasts of GV stage oocytes, around 80% of the reconstructed oocytes could mature in vitro and 7.1-9.4% of the oocytes developed to blastocyst stage after intracytoplasmic sperm injection (ICSI). Transfer of 93 fertilized eggs reconstructed via GV transfer into six recipients resulted in two live offspring. Results of this experiment indicate that GV transfer can potentially become a new approach in treatment of infertility because of advanced maternal age.

BRG1, a component of the SWI-SNF complex, is mutated in multiple human tumor cell lines

Human BRG1 is a component of the evolutionarily conserved SWI-SNF chromatin remodeling complex. BRG1 has been implicated in growth control through its interaction with the tumor suppressor pRb and may consequently serve as a negative regulator of proliferation. Postulating that BRG1 may itself be a tumor suppressor gene, we screened a panel of tumor cell lines to determine whether the gene is targeted for mutation. We report that the COOH-terminal region of BRG1 is homozygously deleted in two carcinoma cell lines, prostate TSU-Pr1 and lung A-427. In addition, biallelic inactivations of BRG1 were observed in four other cell lines derived from carcinomas of the breast, lung, pancreas, and prostate; their mutations in BRG1 included three frameshift lesions and one nonsense lesion. Point mutations were also discovered in a number of other cell lines, however in most cases any effect of these mutations on BRG1 function remains to be established. A variety of different mutations within BRG1, in several cell lines, suggest that BRG1 may be targeted for disruption in human tumors. Significantly, reintroduction of BRG1 into cells lacking BRG1 expression was sufficient to reverse their transformed phenotype inducing growth arrest and a flattened morphology. These data strongly support the model that BRG1 may function as a tumor suppressor and strengthen the hypothesis that the regulation of gene expression through chromatin remodeling is critical for cancer progression. It will be important to confirm these observations in primary tumors.

[The characteristics diagnosis and treatment of hepatic metastasis of simple immature ovarian teratoma]

OBJECTIVE

To analyze the characteristics of hepatic metastasis of pure immature ovarian teratoma and explore proper diagnosis and treatment.

METHODS

A total of 18 cases with hepatic metastasis of pure immature ovarian teratoma were involved in this study. The clinical stage, operation, chemotherapy and histopathology of primary and secondary tumor as well as the data of long term follow-up were analyzed retrospectively.

RESULTS

All of the hepatic metastatic tumor located on the surface of liver, 66.1% (11/18) of them was clinically stage 3 and 44.4% (8/18) was grade 1 at first operation. The hepatic metastatic rate was 16.7% (3/18) in standard adjuvant chemotherapy group but increased obviously to 31.2% (15/48) in irregular chemotherapy group. Auxiliary diagnostic methods could not indicate correct results. The surgical resection rate of hepatic metastasis of pure immature ovarian teratoma was 94.4% (17/18). There was less complication occurred in the group with the diameter of tumor less than 15 cm. The follow-up time ranged from 3-205 months with the mean of 20.9 months. The 3 year survival rate was 77.8% (14/18), lost of follow-up rate was 0.0% (0/18); The 5 year and 10 year survival rate was 55.6% (10/18) and 38.9% (7/18) respectively, lost of follow-up rate was 22.2% (4/18) and 38.9% (7/18) respectively, one of them had survived for more than 17 years.

CONCLUSIONS

The hepatic metastatic rate of pure immature ovarian teratoma could be decreased by using standard adjuvant chemotherapy. Suitable surgical treatment could reduce complication and improve the prognosis of this kind of patients.

Functional effects of replacing human alpha- and beta-globins with their embryonic globin homologues in defined haemoglobin heterotetramers

Embryonic- and adult-stage globin subunits assemble into haemoglobin (Hb) heterotetramers that are expressed at low levels throughout human intrauterine development. These haemoglobins differ from adult Hb A (alpha2beta2) by the substitution of embryonic zeta for adult alpha globin (Hb zeta2beta2), or embryonic epsilon for adult beta globin (Hb alpha2epsilon2). Several key physiological properties of these 'semiembryonic' haemoglobins remain undefined, as ethical and methodological considerations have limited their availability from both human sources and conventional expression systems. The current study attempts to estimate how the physiological properties of semiembryonic and adult haemoglobins may differ, by determining whether the O2-binding characteristics of hybrid human/mouse haemoglobins change when human alpha- or beta-globin subunits are replaced by human embryonic zeta- or epsilon-globin subunits respectively. Each of the four human globins is expressed in transgenic mice that are nullizygous for either the endogenous mouse alpha- or beta-globin genes, resulting in the high-level expression of haemoglobins that can be studied either in situ in intact erythrocytes or in vitro. We showed that the exchange of human zeta-globin for human alpha-globin chains increased haemoglobin O2 affinity, both in the presence and in the absence of 2, 3-bisphosphoglycerate (2,3-BPG), and reduced the pH-dependent shift in its oxygen equilibrium curve (Bohr effect). By comparison, hybrid haemoglobins containing either human epsilon-globin or human beta-globin exhibited nearly identical O2-binding properties, both in situ and in vitro, regardless of 2,3-BPG levels or ambient pH. Neither the zeta-for-alpha nor the epsilon-for-beta substitutions substantially altered binding affinity for 2,3-BPG or cooperativity between globin subunits. These studies suggest that semiembryonic haemoglobins that assemble entirely from human subunits may exhibit properties that are similar to those of human Hb A.

[Clinical discussion of the relationship between endometriosis and epithelial ovarian cancer]

OBJECTIVE

To analyse the relationship between endometriosis and epithelial ovarian cancer.

METHODS

We analyzed retrospectively the 20 cases associated with endometriosis in 371 cases of epithelial ovarian cancer, and these 20 cases were also compared with the left 351 cases not associated with endometriosis(including endomtriod carcinoma 38 cases and clear cell carcinoma 39 cases).

RESULTS

Among 20 cases, endomtriod carcinoma and clear cell carcinoma were most frequently associated with endometriosis, with 11 cases and 7 cases respectively, there was also 1 case of gland carcinoma and 1 case of serous papillary carcinoma. Cases of carcinomas associated with endometriosis had higher pathological grade and 5-year survival probability (Kaplan-Meier method) than those cases not associated with endometriosis.

CONCLUSIONS

There is a close relationship between endometriosis and ovarian endomtriod carcinoma and clear cell carcinoma, the malignant transformation of endometriosis foci may be an important origin of them. Drug therapy is recommended for endomtriosis after the operation. In the treatment of endomtriod carcinoma and clear cell carcinoma, progestin can be used as an accessory method.

Genomic structure, chromosomal location, and mutation analysis of the human CDC14A gene

Human CDC14A is a dual-specificity phosphatase that shares sequence similarity with the recently identified tumor suppressor, MMAC1/PTEN/TEP1. By radiation hybrid mapping, we localized CDC14A to chromosome band 1p21, a region that has been shown to exhibit loss of heterozygosity in highly differentiated breast carcinoma and malignant mesothelioma. We have mapped the exon-intron structure of CDC14A gene and found an in-frame ATG at 14 codons upstream of the previously reported start site (GenBank Accession No. AF000367). In screening a panel of 136 cDNAs from tumor cell lines for coding mutations, we have identified a 48-bp in-frame deletion in the cDNA of the breast carcinoma cell line, MDA-MB-436. This deletion is the result of an acceptor splice site mutation (AG to AT) in intron 12 that causes the skipping of exon 13 in the gene. Loss of expression of the wildtype allele in the same breast cell line supports the possibility that CDC14A may be a tumor suppressor gene that is targeted for inactivation during tumorigenesis.