[Impact of VA-ECMO combined with IABP and timing on outcome of patients with acute myocardial infarction complicated with cardiogenic shock]

Objective: To investigate the impact of combined use and timing of arterial-venous extracorporeal membrane oxygenation (VA-ECMO) with intra-aortic balloon pump (IABP) on the prognosis of patients with acute myocardial infarction complicated with cardiogenic shock (AMICS). Methods: This was a prospective cohort study, patients with acute myocardial infarction and cardiogenic shock who received VA-ECMO support from the Heart Center of Lanzhou University First Hospital from March 2019 to March 2022 in the registration database of the Chinese Society for Extracorporeal Life Support were enrolled. According to combination with IABP and time point, patients were divided into VA-ECMO alone group, VA-ECMO+IABP concurrent group and VA-ECMO+IABP non-concurrent group. Data from 3 groups of patients were collected, including the demographic characteristics, risk factors, ECG and echocardiographic examination results, critical illness characteristics, coronary intervention results, VA-ECMO related parameters and complications were compared among the three groups. The primary clinical endpoint was all-cause death, and the safety indicators of mechanical circulatory support included a decrease in hemoglobin greater than 50 g/L, gastrointestinal bleeding, bacteremia, lower extremity ischemia, lower extremity thrombosis, acute kidney injury, pulmonary edema and stroke. Kaplan-Meier survival curves were used to analyze the survival outcomes of patients within 30 days of follow-up. Using VA-ECMO+IABP concurrent group as reference, multivariate Cox regression model was used to evaluate the effect of the combination of VA-ECMO+IABP at different time points on the prognosis of AMICS patients within 30 days. Results: The study included 68 AMICS patients who were supported by VA-ECMO, average age was (59.8±10.8) years, there were 12 female patients (17.6%), 19 cases were in VA-ECMO alone group, 34 cases in VA-ECMO+IABP concurrent group and 15 cases in VA-ECMO+IABP non-concurrent group. The success rate of ECMO weaning in the VA-ECMO+IABP concurrent group was significantly higher than that in the VA-ECMO alone group and the VA-ECMO+IABP non-concurrent group (all P<0.05). Compared with the ECMO+IABP non-concurrent group, the other two groups had shorter ECMO support time, lower rates of acute kidney injury complications (all P<0.05), and lower rates of pulmonary edema complications in the ECMO alone group (P<0.05). In-hospital survival rate was significantly higher in the VA-ECMO+IABP concurrent group (28 patients (82.4%)) than in the VA-ECMO alone group (9 patients) and VA-ECMO+IABP non-concurrent group (7 patients) (all P<0.05). The survival rate up to 30 days of follow-up was also significantly higher surviving patients within were in the ECMO+IABP concurrent group (26 cases) than in VA-ECMO alone group (9 patients) and VA-ECMO+IABP non-concurrent group (4 patients) (all P<0.05). Multivariate Cox regression analysis showed that compared with the concurrent use of VA-ECMO+IABP, the use of VA-ECMO alone and non-concurrent use of VA-ECMO+IABP were associated with increased 30-day mortality in AMICS patients (HR=2.801, P=0.036; HR=2.985, P=0.033, respectively). Conclusions: When VA-ECMO is indicated for AMICS patients, combined use with IABP at the same time can improve the ECMO weaning rate, in-hospital survival and survival at 30 days post discharge, and which does not increase additional complications.

Acute pulmonary embolism and severe post thrombolysis renal bleeding, two deadly complications following mini-percutaneous nephrolithotomy: a rare case report

BACKGROUND

Acute pulmonary embolism and severe renal bleeding are two lethal postoperative complications, but there has been no report that involves both of them after mini-percutaneous nephrolithotomy.

CASE PRESENTATION

A 62-year-old woman was admitted to our hospital with extremely severe hydronephrosis and multiple right renal calculi. After thorough examination, she received prone-position mini-percutaneous nephrolithotomy under spinal anaesthesia. Three days postoperatively, the patient complained of chest pain and dyspnea. Computed tomography pulmonary angiogram (CTPA) showed multiple embolisms in the left pulmonary artery and its branches. Symptoms were relieved after anticoagulant and thrombolysis therapy. On the 6th postoperative day, the patient developed shortness of breath, computed tomography angiography (CTA) showed massive hemorrhage in the right kidney, diffused contrast medium in the middle and lower part of the right kidney was seen during digital substraction angiography (DSA). Superselective right renal artery embolization (SRAE) was then applied using coil to occlude the responsible artery. The patient generally recovered under conscientious care and was approved to be discharged 26 days postoperatively.

CONCLUSIONS

This is the first case that involved both acute pulmonary embolism and severe post thrombolysis renal bleeding. The importance of D-dimer in the prediction and early detection of pulmonary embolism should be noted. For post thrombolysis renal bleeding, SRAE is considered as a reliable treatment.

The Use of High-Intensity Focused Ultrasound (HIFU) Plus 150mg Bicalutamide as First Line Salvage Therapy for Local Recurrent Prostate Cancer

Patients with localized prostate cancer (PCa) are often treated with radical prostatectomy (RP). However, more than 30% of such patients have high risk of recurrence. Salvage radiotherapy (SRT), androgen deprivation therapy (ADT) and combination of radiotherapy and ADT are the standard care for recurrent PCa. Recently, high intensity focused ultrasound (HIFU) has gradually applied in the treatment of recurrent PCa. Here, we proposed a hypothesis that combined HIFU and bicalutamide 150mg as first line salvage therapy to treat patients with local recurrent PCa with visible lesions due to the following advantages: (1) HIFU is effective in reducing local tumor load, and bicalutamide 150mg is a feasible and safety option to combine with HIFU. (2) Compared with radiotherapy, HIFU plus 150mg bicalutamide is minimal invasiveness with fewer adverse effects and better quality of life(QOL); (3) Radiotherapy can be preserved as the second-line salvage method in the cases who are failure to HIFU and 150mg bicalutamide combination. More clinical trials are warranted to confirm this hypothesis in treatment with recurrent PCa.

Bilateral hematoma after tubeless percutaneous nephrolithotomy for unilateral horseshoe kidney stones: A case report

BACKGROUND

Bilateral perirenal hematoma is rarely reported in endoscopic management of horseshoe kidney stones, and there are few studies reporting the formation of bilateral hematoma following tubeless percutaneous nephrolithotomy (PCNL) for unilateral horseshoe kidney calculi.

CASE SUMMARY

A 32-year-old man was admitted to our hospital because of repeated intermittent hematuria for 10 years. Plain abdominal computed tomography (CT) scan revealed calculi in the horseshoe kidney; the largest being 2 cm in diameter. Tubeless PCNL was performed to remove the stones. Three days after the operation, the patient was discharged in a stable situation. Three days after discharge, the patient presented to our emergency department because of right low back pain and vomiting. Emergent CT scan revealed subcapsular and perirenal hematocele and exudates in both kidneys. Ultrasound-guided puncture and drainage of perirenal effusion were performed. After the temperature stabilized, the patient received low-pressure injection of urokinase 100000 U for 3 d. His routine blood indexes and the renal function returned to normal in 3 wk. CT re-examination 3 mo after lithotripsy showed that the subcapsular and perirenal hematoma and exudates in both kidneys were significantly absorbed as compared with those before. The patient was followed up for 1 year, during which no flank pain or hematuria recurred.

CONCLUSION

This is the first case report on the formation of bilateral hematoma following tubeless PCNL for unilateral horseshoe kidney calculi.

Atypical granular cell tumor of the urinary bladder: A case report

BACKGROUND

Granular cell tumor (GCT) is a neurogenic tumor mainly occurring in the head and neck. GCT in the genitourinary system is extremely rare and only sporadic cases of urinary bladder GCT have been reported. Most urinary bladder GCT cases are benign and only two malignant cases have been reported. Due to its rarity, no consensus criteria for the treatment of urinary bladder GCT are available at present.

CASE SUMMARY

A 62-year-old Chinese woman was found to have a urinary bladder tumor without any clinical manifestations on physical examination. Cystoscopy revealed a semispherical shaped lesion measuring approximately 4.0 cm in diameter at the junction of the left wall and roof of the bladder, which was covered with normal bladder mucosa. Computed tomography scan demonstrated a high-density lesion on the left wall of the bladder, measuring approximately 2.9 cm × 2.4 cm with clear boundaries. Contrast-enhanced pelvic magnetic resonance imaging revealed a space-occupying lesion on the left wall of the bladder (non-mucosal origin/ external pressure), which was preliminarily suspected to be a desmoplastic fibroma or leiomyoma. In the context of the above findings, a pre-operative diagnosis of bladder leiomyoma was made. The patient consequently underwent a laparoscopic partial cystectomy. The resected bladder mass looked yellowish and well-demarcated, measuring 4.0 cm × 3.5 cm and infiltrated the muscular layer. The diagnosis of urinary bladder GCT was finally made by postoperative pathology, with positive immunohistochemical S-100 staining and negative pancytokeratin. The patient has been followed for 6 mo so far, with no tumor recurrence detected.

CONCLUSION

This case highlights the biological feature and differential diagnosis of urinary bladder GCT at the pathological and molecular levels. Transurethral resection of the bladder tumor and partial cystectomy are recommended in most urinary bladder GCT cases, while radical cystectomy is recommended in malignant cases.

Sinularin exerts anti-tumor effects against human renal cancer cells relies on the generation of ROS

Sinularin, a soft corals-derived natural product, exerts anti-tumorigenic activity in various types of human cancer cells. However, the action of Sinularin and its mechanism in renal carcinoma is not well understood. In the current study, we demonstrated that Sinularin inhibited the viability of human renal cancer cells 786-O and ACHN in a dose- and time-dependent manner, but did not show significant toxicity against non-malignant HRCEpic cells. Cell cycle analysis revealed that Sinularin induced G2/M arrest significantly. In addition, Sinularin could induce apoptosis in cells along with caspase-3/-9 activation, release of mitochondrial proteins, up-regulation of pro-apoptotic Bcl-2 family proteins and inhibition of anti-apoptotic Bcl-2 family proteins. Sinularin could also repress the activation of PI3K/Akt/mTOR signaling pathway. Moreover, Sinularin triggered the activation of MAPKs and p38 activation was essential for the anti-tumor effect of Sinularin. The generation of ROS (reactive oxygen species) was critical for Sinularin-induced apoptosis since ROS scavenger NAC (N-acetyl cysteine) could block the Sinularin-triggered apoptosis. In conclusion, all the results indicated that Sinularin may be applied as a therapeutic natural agent for human renal cancer.

Comparison of levofloxacin-based prophylaxis regimens for transrectal prostate biopsy: a prospective randomized single-center study

To develop an optimal prophylactic regimen among Chinese patients who accept transrectal prostate biopsy. We enrolled 420 patients who accepted transrectal prostate biopsy. They were randomly classified into three groups (n = 140 for each): Group A received a single 500-mg tablet of levofloxacin without enema; group B received a single 500-mg tablet of levofloxacin plus enema; group C received 3-day levofloxacin orally plus enema. Patients were assessed if they had a febrile urinary tract infection (FUTI). The incidence of FUTI was compared among groups. Subgroup analysis was performed between patients at high and low risk of infection in each group. There were 15 cases developed FUTI: 7 (5%), 6 (4.3%), and 2 (1.4%), respectively, in groups A, B, and C. Of the 15 patients who developed FUTI, Escherichia coli was detected in blood culture in two cases. Urine culture results were all negative. FUTI patients (73.3% (11/15)) had at least one high risk factor. Subgroup analysis showed that the incidence of FUTI in group A was significantly higher than that in group C among high-risk patients. There was no statistical difference between group A and group B among both high- and low-risk patients. A single 500-mg dose of levofloxacin without enema represents excellent prophylaxis for transrectal prostate biopsy in Chinese patients at low risk of infection. For those at high risk, 3-day levofloxacin prophylaxis is the optimal regimen. Prebiopsy enema provides no clinically significant outcome advantage and is unnecessary.

Knockdown of DUXAP10 inhibits proliferation and promotes apoptosis in bladder cancer cells via PI3K/Akt/mTOR signaling pathway

DUXAP10 is a member of long non-coding RNAs (lncRNAs) and has been reported to be upregulated in bladder cancer (BC) tissues. However, the biological functions of DUXAP10 in BC are largely unknown. The present study detected the expression of DUXAP10 in human normal bladder cell SV‑HUC‑1 and BC cell lines. Subsequently, cell proliferation, cell cycle, and apoptosis were analyzed by knockdown of the DUXAP10 expression. Results suggested that the expression level of DUXAP10 was significantly enhanced in cancer cells. After knockdown of DUXAP10, cell proliferation was inhibited, cell cycle was arrested at G0/G1 phase, and apoptosis was increased in T24 and 5637 cells. Western blot analysis detected that knockdown of DUXAP10 decreased the expression of Bcl-xL, cyclin D and CDK4. This increased the expression of Bad, cleaved caspase‑3, cleaved caspase-9, and p27. Further studies indicated that knockdown of DUXAP10 inhibited PI3K/Akt/mTOR signaling pathway. Combining these results, our study suggests that DUXAP10 plays an important role in BC and DUXAP10 inhibition is a potential therapeutic target for BC.

Chinese Shang Ring Male Circumcision: A Review

Chinese Shang Ring adult male circumcision (SC) is a safe and effective procedure which is easy to learn and to perform. By a specially designed small device, male circumcision (MC) can be performed in 5 min. Compared with conventional adult MC (CC), SC has shorter operation time, less blood loss, less pain score, higher appearance satisfaction rate, and lower complication rate. SC was first developed in China. As recent studies have demonstrated that MC reduced the risk of acquiring human immunodeficiency virus (HIV) infection via vaginal intercourse in African countries, SC was introduced into Africa to fight HIV. Other sexually transmitted diseases such as human papillomavirus infection may also be prevented by SC. In conclusion, Chinese Shang Ring, a small device, provides an easy, quick, safe, and effective method to perform adult MC.

[Diagnostic Values of IL-12 and IFN-γ for the Patients with Acute Leukemia]

OBJECTIVE

To explore the diagnostic values of interleukin-12 (IL-12) and interferon-γ (IFN-γ) for the patients with acute leukemia (AL).

METHODS

A total of 76 cases of AL were enrolled in this study, and the 40 healthy persons were used as control group. The levels of IL-12 and IFN-γ were determined by enzyme linked immunosorbent assay (ELISA). The results were analyzed.

RESULTS

The levels of IL-12 and IFN-γ in the untreated AL group, ALL and ANLL groups were lower significantly than those in the control group (P<0.05), there was no significant difference between untreated AL and ANLL groups (P>0.05). The levels of IL-12 and IFN-γ in CR patients of AL group after treatment obviously higher than that of patients before treatment (P<0.05), but there was no significant difference as campared with that in control. The levels of IL-12 and IFN-γ in NR patients of AL group after treatment were obviously lower than that in control group (P<0.05), but there was no significant difference in comparision with patients before treatment (P>0.05). The levels of IL-12 and IFN-γ of AL-CR and AL-NR patients before treatment were not significant difference before treatment (P>0.05). The levels of IL-12 and IFN-γ of AL-CR patients obviously higher than that in AL-NR patients (P<0.05). According to immure classification, the levels of IL-12 and IFN-γ of patients in untreated group were not significant difference. In regard to the clinical risk degree, the level of IL-12 of patients in untreated group was not obvious difference (P>0.05), but the level of IFN-γ of patients in untreated group was obvious different (P<0.05). The level of IL-12 of patients in untreated group positively correlated with level of IFN-γ (r=0.735, P<0.05), but the level of IL-12 did not significantly correlated with the level of IFN-γ (r=0.292, P>0.05).

CONCLUSION

The serum levels of both IL-12 and IFN-γ are lower, but the changes of both serum levels may be helpful to diagnose and treatment of AL patients.

Anti-tumor effects of Atractylenolide I on bladder cancer cells

BACKGROUND

Atractylenolide I (ATR-1), an active component of Rhizoma Atractylodis Macrocephalae, possesses cytotoxicity against various carcinomas. However, little is known about the effects of ATR-1on bladder cancer. In the present study, the anti-tumor activity of ATR-1 was examined on bladder cancer cells both in vivo and in vitro.

METHODS

MTT assay was used to assess the cytotoxic effect of ATR-1. Cell cycle distribution and apoptosis levels were evaluated using flow cytometry. Western blotting assay was applied to measure the levels of proteins associated with the apoptotic pathway, cell cycle progression and PI3K/Akt/mTOR signaling pathway. Tumor models in nude mice were induced by injection of T-24 and 253J human bladder cancer cells.

RESULTS

ATR-1 inhibited bladder cancer cell proliferation, arrested cell cycle in G2/M phase through up-regulation of p21 and down-regulation of cyclin B1, CDK1 and Cdc25c. Meanwhile, ATR-1 also triggered cellular apoptosis depending on the activation of mitochondrial apoptotic pathway. Mechanism investigation indicated that ATR-1 exerts its anti-tumor effect also relies on the inhibition of PI3K/Akt/mTOR signaling pathway. Finally, mice studies showed that ATR-1 blocked the T-24 or 253J-induced xenograft tumor growth without noticeable toxicity.

CONCLUSIONS

ATR-1 may be served as a potential therapeutic agent for the treatment of bladder cancer.

[Sexual function and mental state in patients with redundant prepuce or phimosis]

OBJECTIVE

To investigate the correlation of sexual dysfunction with psychological abnormalities by analyzing the sexual function and mental state of the patients with redundant prepuce or phimosis.

METHODS

This study included 216 randomly selected patients with redundant prepuce or phimosis and 85 normal male controls. We conducted investigations among the subjects using a questionnaire on the general data of the patients, Chinese Index of Sexual Function for Premature Ejaculation (CIPE), International Index of Erectile Function (IIEF), and Symptom Checklist 90 (SCL-90). Then we assessed the status of premature ejaculation (PE) and erectile dysfunction (ED), calculated the incidence of psychological abnormalities, such as depression and anxiety, and analyzed the correlation of PE and ED with the mental state of the patients.

RESULTS

The PE and ED patients scored significantly higher than normal controls on SCL-90, somatization, compulsion, depression, anxiety and other factors (P < 0.05). CIPE scores were correlated with the scores on SCL-90, somatization, compulsion, interpersonal sensitivity, depression, anxiety and other factors, while ED-related scores showed no correlation with the scores on SCL-90 and other factors.

CONCLUSION

Patients with redundant prepuce or phimosis have poor mental health, and there is an interaction between PE and the mental state of the patient.

[A recommendable standard protocol of adult male circumcision with the Chinese Shang Ring: outcomes of 328 cases in China]

OBJECTIVE

Standardization of and training in adult male circumcision can significantly reduce its complication rate. Currently no such program exists for its standardization and training, making it difficult to guarantee the quality of male circumcision services. We therefore established a standardized surgical protocol for adult male circumcision in China using the Shang Ring, and applied it to a clinical study examining the performance of the Shang Ring in adult male circumcision.

METHODS

A total of 328 adult men aged 18-58 (mean 27.8) years, 25 with phimosis and 303 with redundant prepuce, underwent circumcision with the Shang Ring, and evaluation of the operation time, pain scores (using the visual analog scale), postoperative complications, time for wound healing, and their satisfaction with the postoperative appearance.

RESULTS

The operation time was 4.7 +/- 1.3 minutes. The pain scores were 0. 2 +/- 0.6 during the surgery, 1.6 +/- 1.0 twenty hours postoperatively, 1.7 +/- 1.1 twenty hours prior to the ring removal, and 2.7 +/- 1.4 during the ring removal. Complications included infection in 2 (0.6%), bleeding in 2 (0.6%), and wound dehiscence in 2 (0.6%) of the patients. None of the patients with wound dehiscence required postoperative suturing and all were managed conservatively instead. Sixteen of the patients (4.9%) experienced penile edema. The time for complete wound healing after circumcision was 20.3 +/- 6.7 days. The rate of the patients'satisfaction was 99.7% (327/328).

CONCLUSION

The standard protocol of adult male circumcision with the Shang Ring has the advantages of short operation time, slight pain, low rate of complications, and high satisfaction and acceptance of the patients. Strict standardization of the surgical protocol can maximize its clinical advantages for adult male circumcision.

[Effects of LRIG1 gene on the invasion of bladder cancer in vitro]

OBJECTIVE

To observe the change of invasion ability of the bladder cancer cell line BIU87 after transfected with LRIG1 gene.

METHODS

Plasmid pLRIG1-GFP was transfected into bladder cancer cells (BIU87) by Lipofectamine 2000, and cells that could express LRIG1 stably was screened out by G418. The alteration of cellular invasion property of BIU87, BIU87-neo and BIU87-LRIG1 cells was evaluated by Boyden chamber. The expression of mRNA and protein of LRIG1 and EGFR was detected by RT-PCR and Western-blot.

RESULTS

Compared with BIU87 and BIU87-neo cells, after BIU87 cell line was transfected with plasmid pLRIG1-GFP, the invasion ability decreased significantly, the expression of mRNA and protein of LRIG1 was obviously up-regulated and that of EGFR was down-regulated (P < 0.01).

CONCLUSION

LRIG1 gene can significantly inhibit the invasion ability of BIU87 cell line.

LRIG1, a candidate tumour-suppressor gene in human bladder cancer cell line BIU87

OBJECTIVES

To determine the effects of LRIG1 on the growth, migration and invasion of bladder cancer cells and the mechanisms underlying such effects.

MATERIALS AND METHODS

The plasmid pLRIG1-green fluorescence protein (GFP) was transfected into BIU87 bladder cancer cells by Lipofectamine2000 (Invitrogen, Groningen, the Netherlands), and the cells that expressed LRIG1 stably were screened out by G418. The changes in LRIG1 and epidermal growth factor receptor (EGFR) protein levels were measured by Western blot; growth curves were estimated by the tetrazolium (MTT) assay; then cell-cell adhesion, cell-matrix adhesion and cell invasion assays were used to measure proliferation, adhesion and invasion in LGIR1-transfected and control cells.

RESULTS

The LRIG1 protein level in pLRIG1-GFP transfected cells was significantly higher than that in control cells, while the EGFR protein level was significantly lower. pLRIG1-GFP transfected cells had less proliferation than control cells. Contrasting with non-LRIG1-transfected cells, the invasion and cell-matrix adhesion ability of pLRIG1-GFP transfected cells decreased markedly, and conversely the homotypic cell-cell adhesion ability was significantly higher.

CONCLUSIONS

LRIG1 might act as a tumour-suppressor gene, participating in negative feedback control of EGFR expression, which inhibits bladder cancer cells from growth, migration and invasion.

The 5'-flanking cis-acting elements of the human epsilon-globin gene associates with the nuclear matrix and binds to the nuclear matrix proteins

The nuclear matrix attachment regions(MARs) and the binding nuclear matrix proteins in the 5'-flanking cis-acting elements of the human epsilon-globin gene have been examined. Using in vitro DNA-matrix binding assay, it has been shown that the positive stage-specific regulatory element (epsilon-PREII, -446 bp(-)-419 bp) upstream of this gene could specifically associate with the nuclear matrix from K562 cells, indicating that epsilon-PREII may be an erythroid-specific facultative MAR. In gel mobility shift assay and Southwestern blotting assay, an erythroid-specific nuclear matrix protein (epsilon-NMP kappa) in K562 cells has been revealed to bind to this positive regulatory element (epsilon-PREII). Furthermore, we demonstrated that the silencer (-392 bp(-)-177 bp) upstream of the human epsilon-globin gene could associate with the nuclear matrices from K562, HEL and Raji cells. In addition, the nuclear matrix proteins prepared from these three cell lines could also bind to this silencer, suggesting that this silencer element might be a constitutive nuclear matrix attachment region (constitutive MAR). Our results demonstrated that the nuclear matrix and nuclear matrix proteins might play an important role in the regulation of the human epsilon-globin gene expression.

Visualization of chromatin folding patterns in chicken erythrocytes by atomic force microscopy (AFM)

The organization of the higher order structure of chromatin in chicken erythrocytes has been examined with tapping-mode scanning force microscopy under conditions close to their native environment. Reproducible high-resolution AFM images of chromatin compaction at several levels can be demonstrated. An extended beads-on-astring (width of approximately 15-20 nm, height of approximately 2-3 nm for each individual nucleosome) can be consistently observed. Furthermore, superbeads (width of approximately 40 nm, height of approximately 7 nm) are demonstrated. Visualization of the solenoid conformation at the level of 30 nm chromatin fiber is attained either by using AFM or by using electron microscopy. In addition, tightly coiled chromatin fibers (approximately 50-60 nm and approximately 90-110 nm) can be revealed. Our data suggest that the chromatin in the interphase nucleus of chicken erythrocyte represents a high-order conformation and AFM provides useful high-resolution structural information concerning the folding pattern of interphase chromatin fibers.

Trans-acting factors from the human fetal liver binding to the human epsilon-globin gene silencer

The developmental stage-specific silencing of the human epsilon-globin gene during embryonic life is controlled, in part, by the silencer (-392 bp approximately -177 bp) upstream of this gene. In order to elucidate its role, the nuclear extract from the human fetal liver has been prepared and the interactions between trans-acting factors and this silencer element have been examined. By using DNaseI footprinting assay, a major protected region from -278 bp to -235 bp within this silencer element was identified. Furthermore, we found in gel mobility shift assay and Southwestern blotting assay that there were at least four trans-acting factors (MW approximately 32, 28, 26 and 22 kD) in the nuclear extract isolated from the human fetal liver, which could specifically bind to this region. Our results suggested that these trans-acting factors might play an important role in silencing the human embryonic epsilon-globin gene expression at the fetal stage through the interactions with this silencer.

Biochemical and molecular changes at the cellular level in response to exposure to environmental estrogen-like chemicals

Estrogen-like chemicals are unique compared to nonestrogenic xenobiotics, because in addition to their chemical properties, the estrogenic property of these compounds allows them to act like sex hormones. Whether weak or strong, the estrogenic response of a chemical, if not overcome, will add extra estrogenic burden to the system. At elevated doses, natural estrogens and environmental estrogen-like chemicals are known to produce adverse effects. The source of extra or elevated concentration of estrogen could be either endogenous or exogenous. The potential of exposure for humans and animals to environmental estrogen-like chemicals is high. Only a limited number of estrogen-like compounds, such as diethylstilbestrol (DES), bisphenol A, nonylphenol, polychlorinated biphenyls (PCBs), and dichlorodiphenyltrichloroethane (DDT), have been used to assess the biochemical and molecular changes at the cellular level. Among them, DES is the most extensively studied estrogen-like chemical, and therefore this article is focused mainly on DES-related observations. In addition to estrogenic effects, environmental estrogen-like chemicals produce multiple and multitype genetic and/or nongenetic hits. Exposure of Syrian hamsters to stilbene estrogen (DES) produces several changes in the nuclei of target organ for carcinogenesis (kidney): (1) Products of nuclear redox reactions of DES modify transcription regulating proteins and DNA; (2) transcription is inhibited; (3) tyrosine phosphorylation of nuclear proteins, including RNA polymerase II, p53, and nuclear insulin-like growth factor-1 receptor, is altered; and (4) DNA repair gene DNA polymerase beta transcripts are decreased and mutated. Exposure of Noble rats to DES also produces several changes in the mammary gland: proliferative activity is drastically altered; the cell cycle of mammary epithelial cells is perturbed; telomeric length is attenuated; etc. It appears that some other estrogenic compounds, such as bisphenol A and nonylphenol, may also follow a similar pattern of effects to DES, because we have recently shown that these compounds alter cell cycle kinetics, produce telomeric associations, and produce chromosomal aberrations. Like DES, bisphenol A after metabolic activation is capable of binding to DNA. However, it should be noted that a particular or multitype hit(s) will depend upon the nature of the environmental estrogen-like chemical. The role of individual attack leading to a particular change is not clear at this stage. Consequences of these multitypes of attack on the nuclei of cells could be (1) nuclear toxicity/cell death; (2) repair of all the hits and then acting as normal cells; or (3) sustaining most of the hits and acting as unstable cells. Proliferation of the last type of cell is expected to result in transformed cells.

Mutations in DNA polymerase beta mRNA of stilbene estrogen-induced kidney tumors in Syrian hamster

We report here the alteration(s) in the expression of the DNA repair gene, DNA polymerase beta, in kidney tumors induced by stilbene estrogen (diethylstilbestrol, DES). RT-PCR, slot blotting, and Northern blotting experiments revealed that expression of DNA polymerase beta (DNA pol beta) was several fold lower in stilbene-estrogen-induced kidney tumors than in age-matched controls. Several mutations were identified in DNA pol beta mRNA from DES-induced kidney tumors, but not in age-matched control kidney. The mutations in DNA pol beta mainly occurred in the catalytic domain of pol beta, and not in the DNA binding domain. All the mutations produced a stop codon at nucleotide 199 indicating that a protein of aberrant size may be synthesized. These data suggest that mutation of DNA pol beta coupled with attenuation in expression might compromise the DNA repair system. This in turn may allow a greater error rate during DNA repair and the accumulation of lesions in the genome.

Dissecting the hematopoietic microenvironment. VII. The production of an autostimulatory factor as well as a CSF by unstimulated murine marrow fibroblasts

Purified normal murine bone marrow-derived fibroblasts were shown to produce a factor that stimulates the in vitro growth of fibroblastic colony-forming unit (CFU-F) colonies. Conditioned medium from the purified fibroblasts (F-CM) also stimulated pure marrow fibroblasts themselves. Analysis of the F-CM detected the presence of macrophage colony-stimulating factor (M-CSF), and low levels of interleukin 1 (IL-1) and interleukin 6 (IL-6), but no detectable levels of interleukin 3 (IL-3), interleukin 5 (IL-5), granulocyte-macrophage colony-stimulating factor (GM-CSF), or granulocyte colony-stimulating factor (G-CSF). Macrophages and endothelial cells, freed from other bone marrow components, required the F-CM if no other growth factors were added. We conclude that F-CM contains an autocrine factor, which the evidence suggests is IL-1, for bone marrow fibroblasts, and a paracrine factor (CSF-1) for macrophages and/or endothelial cells.

Dissecting the hematopoietic microenvironment. VI. The effects of several growth factors on the in vitro growth of murine bone marrow CFU-F

The effects of several growth factors on the proliferation of fibroblastic colony-forming units (CFU-F) were studied. In the present study CFU-F colonies were found to consist of fibroblasts, macrophages, and endothelial cells. Growth factors, including interleukin 3 (IL-3), interleukin 1 alpha (IL-1 alpha), epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), macrophage colony-stimulating factor (M-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and buffalo rat liver cell-conditioned medium (BRL-CM) were tested for stimulation of the proliferation of CFU-F in a standard culture in both 2% and 15% serum. Overall, the colony numbers produced in 15% serum were much higher than in 2% serum with or without growth factors. However, the influence of several growth factors on CFU-F cultured in 2% serum was relatively greater than in 15% serum when compared to controls. The stimulation of CFU-F by FGF only occurred in culture with 15% serum, and the stimulation by PDGF only occurred with 2% serum. Overall, the strongest stimulations were produced by PDGF, IL-3, and BRL-CM. Combining the other growth factors with IL-3, PDGF, or IL-1 alpha enhanced their effects only modestly. The stimulation by growth factors included increases of the cell numbers between and within colonies as well as an increase in the number of colonies. The study produced results that suggest a complex interaction mediated by growth factors between fibroblasts and other stromal cells within the CFU-F colonies and within the bone marrow itself.

Characterization of murine thymocyte subpopulations reacting with Dolichos bifloris agglutinin

Reactivity of murine thymocytes with the Dolichos bifloris agglutinin (DBA) was examined using flow cytometry. This agglutinin, which has nominal specificity for alpha-linked N-acetyl-D-galactosamine residues, labels 1-4% of unfractionated BALB/c thymocytes. Among thymocyte subpopulations identified on the basis of CD4/CD8 labeling, DBA bound to a substantial percentage of the CD4-8- thymocyte subpopulation. In addition, small populations of thymocytes expressing CD4 and/or CD8 were also labeled with DBA, but with less intensity then seen on many CD4-8- cells. Within the CD4-8- thymocyte population, labeling with DBA was positively correlated with reactivity with J11d antibody, the expression of IL-2 receptor and high levels of the homing receptor molecule, MEL-14. Reactivity with DBA was negatively correlated with the expression of Lyt-1, V beta 8 TCR determinants, and CD3.

Medullary epithelial cell lines from murine thymus constitutively secrete IL-1 and hematopoietic growth factors and express class II antigens in response to recombinant interferon-gamma

In this report, we describe the generation of two cloned epithelial cell lines, TE-71 and TE-75, from murine thymus. These cell lines resemble medullary thymic epithelium by a number of criteria, including reactivity with the monoclonal antibodies A2B5 and ER-TR5, the fucose-specific lectin derived from Ulex europeus, and the expression of keratins normally expressed by medullary thymic epithelial cells in situ. Constitutive Class II antigen expression by these cells is not detectable at the light or electron microscopic level or with flow cytometry. Following exposure to recombinant interferon-gamma or supernatants from mitogen-stimulated spleen cells, expression of Class II antigens by these thymic epithelial cell lines is increased, although less than the levels expressed by spleen cells. Medium conditioned by TE-71 and TE-75 cells exhibited colony-stimulating activity for bone marrow cells. In addition, TE-71-conditioned medium exhibited IL-1-like activity which could be neutralized with anti-IL-1 antibodies.