[A follow-up study on the pain changes trend and effects in patients diagnosed with herpes zoster in Beijing City]

Objective: To understand the changes in pain and its effects in patients with the diagnosis of herpes zoster. Methods: A total of 3 487 patients diagnosed with herpes zoster (HZ) for the first time at the outpatient department of Miyun District Hospital from January 1, 2017, to December 31, 2019, were included in the study. The information of patients was registered and issued with a record card. Patients were required to record the time of pain and rash by themselves. Telephone follow-up was conducted at 21, 90, 180 and 365 days after the onset of rashes, including hospitalization, location of rash and pain, and the time of start and end. The impact of pain on life was evaluated by the Zoster Brief Pain Inventory (ZBPI). Results: The age of 2 999 HZ patients included in the analysis were (53±16) years old, including 1 377 (45.91%) males and 1 903 (63.45%) patients aged 50 years and older. After 21 days of rash, mild, moderate and severe pain accounted for 20.87% (626 cases), 37.98% (1 139 cases) and 33.81% (1 014 cases), respectively. Only 5.07% (152 cases) had no pain or discomfort, and 2.27% (68 cases) had no pain but discomfort. Most of the pain sites were consistent with the rash sites. The chest and back and waist and abdomen were the most common, accounting for 35.58% (1 067 cases) and 29.18% (875 cases), respectively, followed by the limbs and face and neck, accounting for 16.74% (502 cases) and 16.40% (492 cases), respectively. The M (Q1, Q3) of pain days in the HZ patients was 14 (8, 20) days, and the incidence of post-herpetic neuralgia (PHN) was 6.63% (171/2 580) (excluding 419 patients who refused to visit or lost to visit on 90 days after the onset of rash). The pain score of HZ patients within 21 days after the rash was (5.19±2.73) points, and the pain score of PHN patients was (7.61±2.13) points, which was significantly higher than that of non-PHN patients [(5.04±2.69) points] (P<0.001). Daily activities, emotions, walking ability, work, social interaction, sleep and recreation were affected for 21 days after the rash in HZ patients, ranging from 60.79% to 83.83%, with sleep being the most affected (83.83%). The impact scores of pain and life dimensions in PHN patients ranged from 4.59 to 7.61 points on the ZBPI scale, which were higher than those in non-PHN patients (2.49-5.04) (t values ranged from 8.86 to 11.67, all P values <0.001). Conclusion: The proportion of pain in HZ patients after the diagnosis is high, and the pain is more obvious in patients with PHN and HZ patients aged 50 and older, which has a greater impact on their daily lives.

[Reconstruction of teaching mode of Human Parasitology among rural order-oriented medical students in the context of curriculum ideology and politics]

To set the cultivation goal with adaptation to rural order-oriented medical students, the teaching mode of Human Parasitology was reformed in the context of curriculum ideological and political education. The new teaching mode not only enables students to harvest medical knowledge during the school education stage, but also plays a guiding role in cultivation of humanistic qualities and professional spirit, which provides a basis for cultivating general practitioners serving for grassroots healthcare.

PD-L1 Expression is Highly Associated with Tumor-Associated Macrophage Infiltration in Nasopharyngeal Carcinoma

Purpose

Tumour-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment and provide a barrier against the cytotoxic effector functions of T cells and natural killer (NK) cells. Recently, TAMs have become increasingly recognised as an attractive target in combination therapy with PD-1/PD-L1 immuno-checkpoint blockades (ICBs). However, the relationship between PD-L1 expression and TAMs remains unknown in nasopharyngeal carcinoma (NPC).

Patients and Methods

A total of 212 NPC patients from Nanfang hospital were collected in this study. We evaluated the expression of PD-L1 in tumor cells, CD68 (pan-macrophages), and CD163 (M2-like macrophage) in NPC tissues using immunohistochemical (IHC) staining.

Results

The positivity of PD-L1 on tumor cells was 61.3% (130/212). The infiltration densities of CD68+ cells and CD163+ cells in PD-L1-positive NPC tissues were significantly higher than those in PD-L1-negative NPC tissues (P=0.0012 for CD68; P<0.0001 for CD163). Logistic regression analysis showed that high densities of CD68+ macrophages and CD163+ TAMs were significantly associated with increased PD-L1 expression. Subgroup analyses demonstrated that a positive PD-L1 expression on tumor cells in combination with lower CD163+ TAMs density was significantly associated with favorable prognosis, whereas negative PD-L1 expression on tumor cells with higher CD163+ TAMs density was associated with worse prognosis.

Conclusion

The PD-L1 expression in tumor cells was positively correlated with TAMs density in tumor microenvironment of NPC, suggesting TAMs as a new target for combination therapy to improve the response rate of ICBs in NPC treatment.

Comparison and optimization of extraction protocol for intracellular phosphorus and its polyphosphate in enhanced biological phosphorus removal (EBPR) sludge

Intracellular polyphosphate (poly-P) plays important roles in Enhanced biological phosphorus removal (EBPR) process, but an effective and reliable protocol for extracting intracellular P and its poly-P in EBPR sludge without hydrolysis of poly-P has not been setup yet. In the study, it was revealed that the severe hydrolysis of intracellular poly-P occurred during the different extraction processes, such as acid (i.e., HClO₄, H₂SO₄ and HCl), basic (i.e., NaOH and KOH) and freezing-grind (under different solid-liquid ratios), but it did not occur during ultrasonic extraction process. The optimal extraction process of the ultrasonic protocol was 10 w/mL of ultrasonic power density and 15 min of ultrasonic time, when the extraction efficiency of intracellular P was 88.24 ± 1.56%. In addition, the extraction efficiency of intracellular P could be furtherly improved by that the 0.75 mol/L LiCl solution was used to resuspend the bacterial cell before ultrasonic extraction (i.e., LiCl-ultrasonic protocol). The ultrasonic protocol was more suitable to extract the intracellular P and its poly-P of EBPR sludge than the other 4 protocols (i.e., PCA-NaOH, EDTA-NaOH, freezing-grind and LiCl-ultrasonic), which had the technical characteristics of (i) with relatively high extraction efficiency of intracellular P, (ii) without hydrolysis of intracellular poly-P, (iii) with weak noise signal in ³¹P NMR spectrum and (iv) with simple extraction process and short extraction time. It was founded by the ultrasonic protocol that there was the high content (82.88%-89.79% of intracellular P content) of intracellular poly-P with long average chain length (376.4-383.2) in the EBPR sludges. Importantly, it was confirmed that the EBPR process was related to the combined action of extracellular and intracellular poly-P using a new fractionation method of P in EBPR sludge, which included the ultrasonic protocol at high power density for extracting the intracellular P and its poly-P.

[Analysis of herpes zoster incidence and hospitalization in three areas of Beijing in 2015 based on health information system of medical institutions]

Objective: Using data of health information system (HIS) of medical institutions to study the incidence and hospitalization of herpes zoster in three districts of Beijing. Methods: According to the different level of economic development and geographical features in Beijing, 3 districts of Xicheng, Changping and Miyun were chosen and all 110 medical institutions of the first level and above in the 3 districts are included in the survey. All the outpatient and inpatient herpes zoster cases in 2015 were retrospectively reviewed by HIS system. After distinguishing the reduplicated cases, Using the first outpatient case as a molecule and the resident population as denominator to estimate the annual incidence rate, as well as the annual hospitalization rate was estimated based on primary diagnostic hospitalized cases as molecule and the resident population as denominator. Results: A total of 32 313 primary visit outpatient cases were investigated, of which 18 360 cases (56.8%) were women and 20 923 cases (64.8%) were ≥50 years old. The overall estimated incidence of the 3 districts was 8.8‰ with an increase trends with age and reached to the highest in ≥80 years old (30.5/1 000). The incidence of Xicheng, Changping and Miyun districts are respectively 16.2‰, 4.0‰ and 5.7‰. A total of 701 primary visit inpatient cases were identified, of which 366 cases (52.2%) were women and 651 cases (92.9%) were ≥50 years old. The estimated annual hospitalization rate was 19.4/100 000, with the primary and secondary diagnostic hospitalization rate are respectively 5.9/100 000 (212 cases) and 13.5/100 000 (489 cases). The disease types of secondary diagnostic inpatient herpes zoster cases were as follows: cardiovascular disease (19.0%, 93 cases), stroke (14.5%, 71 cases), pneumonia/chronic obstructive pulmonary disease (14.1%, 69 cases), tumor (12.5%, 61 cases) and diabetes (5.7%, 28 cases). Conclusion: Most of the herpes zoster cases in Beijing are over 50 years old, and the incidence of female is slightly higher than male. This disease should become a public health issue of great concern.

Neuroprotective role of dexmedetomidine pretreatment in cerebral ischemia injury via ADRA2A-mediated phosphorylation of ERK1/2 in adult rats

Neuroprotective effects of dexmedetomidine (Dex) have been reported in various models of brain injury. However, to our knowledge, the neuroprotective mechanism of Dex pretreatment in rats remains unknown. The aim of the present study was to detect the expression of the α2A adrenergic receptor (ADRA2A) in focal ischemic brain tissues and to investigate the protective role and corresponding mechanism of Dex pretreatment in cerebral ischemia in rats. A hypoxia/reoxygenation (H/R) cell model in primary cultured astrocytes and a focal cerebral ischemia/reperfusion (I/R) model in adult rats were used. The expression of ADRA2A and extracellular signal-regulated kinases 1 and 2 (ERK1/2) in the primary cultured astrocytes and rat brain ischemic tissues was detected in the different conditions prior to and following Dex pretreatment using western blotting. The H/R model of primary cultured astrocytes and the focal cerebral I/R model in adult rats were successfully constructed. Under the normal oxygen conditions, 500 ng/ml Dex pretreatment increased the expression of ADRA2A and phosphorylated (p)-ERK1/2 in the astrocytes compared with in the control group. Hypoxic culture for 6 h and then reoxygenation for 24 h decreased the levels of p-ERK1/2 in the astrocytes compared with those in control group. This decrease was prevented by Dex pretreatment for 3 h. The hypoxic culture and then reoxygenation increased the expression of ADRA2A. Similarly, compared with those prior to Dex treatment, the levels of ADRA2A and p-ERK1/2 in the brain ischemic tissues following Dex treatment were increased. The levels of ADRA2A and p-ERK1/2 were 0.72±0.23 and 0.66±0.25 following Dex treatment, compared with 0.76±0.22 and 0.31±0.18, respectively, prior to Dex treatment. The effect of Dex pretreatment increasing p-ERK1/2 expression was attenuated by AG1478 pretreatment. In summary, Dex appeared to promote phosphorylation of ERK1/2 in astrocytes under H/R. As a specific agonist of ADRA2A, Dex may activate phosphorylation of ERK1/2 via ADRA2A in astrocytes. Thus, the neuroprotective role of Dex pretreatment against cerebral ischemic injury may function via ADRA2A-mediated phosphorylation of ERK1/2.

Exosomal miR-9 inhibits angiogenesis by targeting MDK and regulating PDK/AKT pathway in nasopharyngeal carcinoma

Background

Exosomes are small vesicles containing a wide range of functional proteins, mRNA and miRNA. Exosomal miRNAs from cancer cells play crucial roles in mediating cell-cell communication and tumor-microenvironment cross talk, specifically in enabling metastasis and promoting angiogenesis. We focused on miR-9 that was identified as a tumor suppressor previously in nasopharyngeal carcinoma (NPC) tumorigenesis.

Methods

Differential centrifugation, transmission electron microscopy and nanoparticle tracking analysis were used to isolate and identify exosomes. Quantitative PCR and western blotting analysis were used to detect miR-9, pri-miR-9, CD63, TSG101, MDK, P70S6K P-Ser424 and PDK1 P-Ser241 expression. Laser confocal microscopy was used to trace exosomal miR-9 secreted by NPC cells into HUVECs. The effect of exosomal miR-9 on cell migration and tube formation of HUVECs in vivo and vitro was assessed by using migration assay, tube formation assay and matrigel plug assay, respectively. Bioinformatics analysis and luciferase reporter assay were utilized to confirm the binding of exosomal miR-9 to the 3′untranslated region (3′-UTR) of MDK, while Phosphorylation Array was performed to identify AKT Pathway in HUVECs treated with exosomal miR-9. Furthermore, Immunohistochemistry (IHC) and in situ hybridization (ISH) was used to detected miR-9, CD31 and MDK expression in human NPC tumor samples.

Results

NPC cells transfected with miR-9-overexpressing lentivirus, released miR-9 in exosomes. Exosomal miR-9 directly suppressed its target gene - MDK in endothelial cells. Mechanistic analyses revealed that exosomal miR-9 from NPC cells inhibited endothelial tube formation and migration by targeting MDK and regulating PDK/AKT signaling pathway. Additionally, the level of MDK was upregulated in NPC tumor samples and was positively correlated with microvessel density. Notably, the level of exosomal miR-9 was positively correlated with overall survival, and MDK overexpression was positively associated with poor prognosis in NPC patients, suggesting the clinical relevance and prognostic value of exosomal miR-9 and MDK.

Conclusions

Taken together, our data identify an extracellular anti-angiogenic role for tumor-derived, exosome-associated miR-9 in NPC tumorigenesis and prompt further investigation into exosome-based therapies for cancer treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0814-3) contains supplementary material, which is available to authorized users.

A Retrospective Study to Compare Five Induction Chemotherapy Regimens Prior to Radiotherapy in the Reduction of Regional Lymph Node Size in Patients with Nasopharyngeal Carcinoma

BACKGROUND Combined chemotherapy and radiation therapy are used to treat nasopharyngeal carcinoma (NPC). Previous studies have shown that induction chemotherapy, given before radiotherapy, is beneficial in patients with local lymph node metastases. The aim of this study was to evaluate regional lymph node size in patients with NPC and the efficacy of five induction chemotherapy regimens given before radiotherapy. MATERIAL AND METHODS Between December 2007 and June 2011, 190 patients were included in this study, who had regionally advanced NPC (Stages II-IV). Five induction chemotherapy regimens were given prior to radiation: 98 patients (51.6%) received the TPF regimen (docetaxel, cisplatin, and fluorouracil); 56 patients (29.5%) received PF regimen (cisplatin and fluorouracil); 26 patients (13.7%) received the TP regimen (cisplatin and docetaxel); seven patients (3.7%) received combined nimotuzumab with TPF; three patients (1.6%) received a combination of the novel modified recombinant human endostatin (Endostar) with PF. The length and width of the regional lymph nodes were measured using neck B-mode (high-resolution grey scale) ultrasonography before chemotherapy and on the second day following completion of chemotherapy. Gastrointestinal tract and bone marrow suppression were also monitored during and after chemotherapy. RESULTS The TPF chemotherapy induction regimen resulted in an improved early response of lymph node size reduction, compared with the PF and TP chemotherapy induction regimens. The combined use of nimotuzumab with the TPF regimen improved efficacy by 15%. The combined use of Endostar improved the efficacy of the PF regimen by 56% (P<0.05). CONCLUSIONS In a retrospective study in patients with NPC, different induction chemotherapy regimens had different effects on lymph node size before radiation therapy.

[Effect of goal-directed haemodynamic management on the postoperative outcome in elderly patients with fragile cardiac function undergoing abdominal surgery]

Objective: To investigate the effect of goal-directed haemodynamic management based on stroke volume variation (SVV), cardiac index (CI) and mean arterial blood pressure (MAP) on the postoperative outcome in elderly patients with fragile cardiac function undergoing gastrointestinal surgery. Methods: Ninety patients with fragile cardiac function, aged 65-90 years old, ASAⅡ or Ⅲ, NYHA Ⅱor Ⅲ, scheduled for abdominal surgery were enrolled in this study.The patients were randomly assigned to two groups: Experience anesthesia group (group E, n=45) and goal-directed hemodynamic management group (G group, n=45). After anesthesia induction, in group G, the SVV and CI were monitored by Vigileo and according SVV (≤12%), CI (≥2.5 L·min^-1·m^-2) and MAP (maintain the base value of ±20%) to adjust the preloaded infusion fluid and give positive inotropic drugs and positive pressure drugs; in group E, fluid and vasoactive agent were used according to the experience of anesthesiologist.Multi-mode monitoring anesthesia management using BIS, TCI of propofol, low-tidal-volume lung protective ventilation management strategy, body temperature protection, and postoperative multimodal analgesia techniques was performed in the two groups.Values of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT) were recorded before operation, at the end of operation, and postoperative 24 h. The incidence of myocardial infarction/angina, heart failure, arrhythmia and cerebral infarction, renal failure, length of hospitalization, and complications in 30-days after surgery were recorded by telephone follow-up. Results: Crystal, colloid, total liquid of group E were (1 110.20±332.00), (536.65±72.25), (1 677.20±424.44) ml and these of group G were (708.72±240.85), (414.41±74.31), (878.51±199.13) ml, respectively.Compared with group E, the fluid infusion were reduced in group G (t=6.057, 2.701, 9.742, all P<0.05). The lactic acid value of 24 hours after surgery in group G was significantly lower than that in group E [(0.89±0.31) mmol/L vs (1.11±0.43) mmol/L, t=-2.848, P<0.05]. Arterial partial pressure of oxygen at 24 hours after surgery in group G was higher than that in group E [(78.77±6.86) mmHg vs (76.46±10.96) mmHg, t=-1.108, P<0.05]. The length of hospitalization of group G was shorter than that of group E [(12.21±2.20) d vs (13.16±3.84) d, t=-1.341, P<0.05]. The incidence of total complication in hospital and in 30-days after surgery of group G were 10.26% and 5.13%, while these of group E were 29.73% and 24.32%, (χ²=4.545, 4.520, all P<0.05). ΔNT-proBNP₁ (the base value of NT-proBNP's minus the value of NT-proBNP's at the end of the operation) and ΔNT-proBNP₂ (the base value of NT-proBNP's minus the value of NT-proBNP's 24 hours postoperatively) of group G were 12.0(-291.0, 1 517.0) and 0(-6 770.0, 291.0), both higher than these of group E [0(-440.0, 200.0) and -12.0(-7 200, 22.0), (Z=-2.412, -2.163, all P<0.05)]. Conclusion: Goal-directed haemodynamic management based on SVV, CI and MAP could improve the outcome of the elderly patients with fragile heart function undergoing abdominal surgery.

[Genomic diversity and population structure of Helicobacter pylori isolates in China]

Objective: To learn about the overall genomic characteristics and population structure of Helicobacter pylori isolated in China. Methods: In this study, we used 10 public available genome sequences of H. pylori strains isolated in China, combined with other H. pylori sequences from GenBank, to analyzed the overall genomic characteristics of H. pylori isolated in China. Core genes and strain specific genes were determined for a further function definition. Results: A total of 1 203 core genes were found among all sequenced China H. pylori isolates. The number of strain specific genes ranged from 19 to 32. These genes mainly encodes hypothetical proteins which might play an important role in adaption to different hosts. Genomic variation regions were mainly in genes encoding type four secretion systems and restriction modification systems. All the China isolates belong to hpEastAsia group, hspEAsia subgroup. Prophages sequences were found in three China H. pylori strains, carrying key elements required for phage assembly. Conclusion: China H. pylori isolates belong to hpEastAsia group, hspEAsia subgroup, and some isolates contain prophages.

[Analysis of clinical and pathological characteristics of high- risk HPV-negative carcinoma of the uterine cervix]

Objective: To study the clinical and pathological characteristics of HPV-negative cervical cancer patients. Methods: Retrospective analysis of 785 cervical cancer patients in Guangdong Women and Children Hospital from Jan. 2005 to Oct. 2015. By detecting high- risk HPV infection by flow-through hybridization genechip technique. Results: (1)Among 785 cases of cervical cancer, 71 cases were negative for HPV infection tested by genechip technique, accounting for 9.0%(71/785), and the relative light units/cut off(RLU/CO)ratios of these 71 cases were less than 1 by hybird capture Ⅱ(HC-Ⅱ)methods. The results showed that the positive coincident rate of genechip technique detecting result with HC-Ⅱ method was 100.0%(71/71).(2)There was no difference between 43(60.6%)cases from 41-55 years old of 71 cases of HPV-negative patients and 392(54.9%)cases from 41- 55 years old of 714 cases of HPV infection patients(χ²=15.63, P=0.571). Among 71 cases of HPV-negative patients, 32 cases of patients with doing TCT, 6(18.8%)cases for normal, 10(31.2%)cases for atypical squamous cells of undetermined significance(ASCUS), 3(9.4%)cases for atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion(ASC-H), 3(9.4%)cases for low-grade squamous intraepithelial lesions(LSIL), 8(25.0%)cases for hight-grade squamous intraepithelial lesions(HSIL), 2(6.2%)cases for squamous cell carcinoma(SCC). And there were 391 cases of patients with doing thin-prep cytologic test(TCT)of 714 HPV infection patients, 60(15.3%)cases for normal, 61(15.6%)cases for ASCUS, 28(7.2%)cases for ASC-H, 29(7.4%)cases for LSIL, 164(41.9%)cases for HSIL, 49(12.5%)cases for SCC. There was no difference of TCT between HPV infection and HPV-negative patients(P>0.05). Among 70 cases from 71 patients with negative for HPV infection, there were 8(11.4%)cases in stage Ⅰ a, 26(37.1%)cases in stage Ⅰ b1, 12(17.1%)cases in stage Ⅰb2, 11(15.7%)cases in stage Ⅱa, 10(14.3%)cases in stage Ⅱb, 3(4.3%)cases in stage Ⅲ-Ⅳ. There were 118(16.6%)cases in stage Ⅰa, 261(36.8%)cases in stage Ⅰb1, 72(10.1%)cases in stage Ⅰb2, 152(21.4%)cases in stage Ⅱa, 87(12.3%)cases in stage Ⅱb, 20(2.8%)cases in stage Ⅲ-Ⅳ in 710 cases of HPV infection patients, in which there were no difference of clinical stage between HPV infection and HPV-negative patients(P>0.05). Among 69 cases from 71 patients HPV-negative infection, there were 51(73.9%)cases for squamous carcinoma, 13(18.8%)cases for adenocarcinoma, 5(7.2%)cases for adenosquamous carcinoma; and 593(87.2%)cases for squamous carcinoma, 38(5.6%)cases for adenocarcinoma, 39(5.7%)cases for adenosquamous carcinoma, 10(1.5%)case for others were in 680 patients of HPV infection, in which there was significant difference of adenocarcinoma between HPV infection and HPV-negative patients(χ²=11.96, P=0.001). Conclusions: Flow-through hybridization genechip technique is the method of high sensitivity to detect high-risk type HPV, as like HC-Ⅱ method. HPV-negative of cervical cancer occurs mainly in 41- 55 years old. Adenocarcinoma incidence is significantly higher in HPV-negative cases than those patients with infection of HPV positive.

Estrogen/ERR-α signaling axis is associated with fiber-type conversion of upper airway muscles in patients with obstructive sleep apnea hypopnea syndrome

Estrogen is related with the low morbidity associated with obstructive sleep apnea hypopnea syndrome (OSAS) in women, but the underlying mechanisms remain largely unknown. In this study, we examined the relationship between OSAS and estrogen related receptor-α (ERR-α). We found that the expression levels of ERR-α and Myh7 were both downregulated in palatopharyngeal tissues from OSAS patients. In addition, we report that ERR-α is dynamically expressed during differentiation of C2C12 myoblasts. Knockdown of ERR-α via instant siRNA resulted in reduced expression of Myh7, but not Myh4. Furthermore, differentiation of C2C12 cells under 3% chronic intermittent hypoxia, a model resembling human OSAS, was impaired and accompanied by a obvious reduction in Myh7 expression levels. Moreover, activation of ERR-α with 17β-estradiol (E2) increased the expression of Myh7, whereas pretreatment with the ERR-α antagonist XCT790 reversed the E2-induced slow fiber-type switch. A rat ovariectomy model also demonstrated the switch to fast fiber type. Collectively, our findings suggest that ERR-α is involved in estrogen-mediated OSAS by regulating Myhc-slow expression. The present study illustrates an important role of the estrogen/ERR-α axis in the pathogenesis of OSAS, and may represent an attractive therapeutic target, especially in postmenopausal women.

Expression of various protection of telomeres 1 variants is associated with telomere length and radiosensitivity in colon and gastric adenocarcinoma cells in vitro

Protection of telomeres 1 (POT1) is a telomere-binding protein, which binds to the single-stranded DNA extensions of telomeres and regulates telomere length. Different POT1 mRNA variants were examined and compared with telomere length and radiosensitivity in colon and gastric adenocarcinoma cells. POT1 production and telomere lengths were assessed using 10 human cancer cell lines by quantitative polymerase chain reaction (qPCR). POT1 mRNA levels, which were relatively stable, were significantly correlated with telomere length in gastric cancer cells and colon cancer cells, except for HT29 (P<0.01). POT1 v5 indexes were closely associated with radiosensitivity in colon cancer cells and gastric cancer cells (P<0.05). In conclusion, POT1 may be a good marker for the examination of cell-specific telomere length and radiosensitivity.

Positivity of both plasma Epstein-Barr virus DNA and serum Epstein-Barr virus capsid specific immunoglobulin A is a better prognostic biomarker for nasopharyngeal carcinoma

Background

Positivity of plasma Epstein–Barr virus (EBV)-DNA or serum virus capsid antigen-specific IgA (VCA-IgA) is a biomarker for the prognosis of nasopharyngeal carcinoma (NPC). The objective of this study was to determine the value of positivity for plasma EBV-DNA and/or VCA-IgA in predicting the survival of patients with NPC.

Methods

Plasma EBV-DNA and serum VCA-IgA in 506 NPC patients in this retrospective study were detected by quantitative real time polymerase chain reaction and enzyme-linked immunoabsorbent assay, respectively. The value of positivity for EBV-DNA and/or VCA-IgA in predicting the survival of patients with NPC was analyzed.

Results

Patients with positivity for both EBV-DNA and VCA-IgA had significantly shorter periods of relapse free survival (RFS) and overall survival (OS) than those with positive single measure or negative for both measures, and patients with positive single measure had significantly shorter periods of RFS and OS than those with negative for both. Multivariate analysis indicated that the positivity for EBV-DNA and/or VCA-IgA were significant risk factors for shorter periods of RFS and OS.

Conclusion

These data indicated that positivity for both EBV-DNA and VCA-IgA was a better biomarker for the prognosis of patients with NPC. Our findings may provide new references for clinical practice.

•

We analyzed the positivity for EBV-DNA and/or VCA-IgA in predicting NPC survival.

•

Patients with both EBV-DNA(+) and VCA-IgA(+) had significantly shorter RFS and OS.

•

EBV-DNA and/or VCA-IgA were significant risk factors for NPC survival.

MicroRNA-378 functions as an onco-miR in nasopharyngeal carcinoma by repressing TOB2 expression

Increasing evidence indicates that microRNAs (miRNAs) has been implicated in the progression and metastasis of numerous cancers. In particular, abnormal expression of miR-378 has been observed in various cancers and is associated with cell survival, migration, invasion, angio-genesis and tumor growth. Our previous studies have shown that miR-378 was decreased in nasopharyngeal carcinoma (NPC) plasma and was negatively correlated with NPC progression. However, the tissue expression of miR-378 and its biological function remained unknown in NPC. In this study, we report for the first time that expression level of miR-378 was commonly upregulated in both NPC tissues and NPC cell lines compared to normal healthy nasopharyngeal epithelial samples and human nasopharyngeal epithelial cell lines (NP69), respectively, and was opposite to the reported results in plasma. Functional studies showed that upregulation of miR-378 dramatically promoted cell proliferation, colony formation, migration and invasion in vitro, as well as tumor growth in vivo. Bioinformatics analyses were performed to predict the target genes of miR-378, and the following mechanistic investigations revealed that miR-378 overexpression was able to downregulate the expression of transducer of ERBB2 (TOB2), a potential tumor suppressor, and miR-378 silencing enhanced TOB2 expression. In clinical specimens, TOB2 was widely repressed in tumor tissues accompanied by miR-378 overexpression. Taken together, this study indicates that miR-378 regulates TOB2 and may function as an onco-miR in NPC progression, providing a potential target for gene therapy of NPC.

Prognostic value of mitochondrial DNA content and G10398A polymorphism in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related mortality worldwide. Mitochondrial dysfunction has been postulated to render cancer cells resistant to apoptosis based on the Warburg hypothesis. However, few studies have investigated the prognostic value of mitochondrial DNA (mtDNA) content and G10398A polymorphism in NSCLC patients. mtDNA copy number and G10398A polymorphism in 128 NSCLC tissue samples were assessed by real-time PCR (RT-PCR) and PCR-RFLP respectively, and their relationship to prognosis were analyzed by survival analysis and Cox proportional hazards model. In vitro, an mtDNA deletion A549 ρ(0) cell model was utilized to assess the function of mtDNA on radiosensitivity. Cell cycle distribution and reactive oxygen species (ROS) were analyzed to elucidate the potential mechanisms. For the whole group, the median follow-up time and overall survival time were 22.5 and 23.4 months, respectively. Patients with high mtDNA content had a marginally longer survival time than patients with low mtDNA content (P=0.053). Moreover, patients with high mtDNA content plus 10398G had a significantly longer overall survival time compared with those having low mtDNA content plus 10398A (47 vs. 27 months, P<0.05). In addition, multivariate analysis showed that stage and low mtDNA content plus 10398A were the two most independent prognostic factors. In vitro, the A549 ρ(0) cells showed more resistance to radiation than ρ(+) cells. Following radiation, ρ(0) cells showed delayed G2 arrest and lower ROS level as compared to ρ(+) cells. In conclusion, the present study suggests that in patients with NSCLC, low mtDNA content plus 10398A could be a marker of poor prognosis which is associated with resistance to anticancer treatment caused by low mtDNA content plus 10398A polymorphism resulting in mitochondrial dysfunction.

Diagnostic and prognostic value of plasma microRNA deregulation in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is uncommon worldwide but often highly invasive in late stages. Due to its special location and lack of specific symptoms, NPC is hardly detected in regular medical examination at the beginning. Development of sensitive and specific biomarkers should help to save lives against this type of disease. In the present report, we investigated the value of plasma miRNAs for diagnosis and prognosis of NPC. Using candidate approach, we selected 21 miRNAs from literature to compare their expression levels in the plasma of NPC patients and controls. As a result, 5 miRNAs showed diagnostic potentials (P<0.01). Among them, miR-16, -21, -24, and -155 had increased levels in NPC patients, whereas the level of miR-378 was decreased. There was a negative correlation between plasma miRNA expression and cancer progression, where miR-21 was statistically significant in T and N staging and miR-16 and 24 were significant in N staging only. Combination of miR-16, -21, -24, -155, and -378 gives 87.7% of sensitivity and 82.0% of specificity for NPC diagnosis. Without miR-16, combination of the rest 4 miRNAs gives the same sensitivity but a slightly reduced specificity. After treatment, all 5 miRNAs were somewhat back to normal levels in patients without cancer recurrence but the prognostic value was not statistically significant. In conclusion, plasma miRNA expression is a useful biomarker for NPC diagnosis but not for its prognosis. More importantly, it is simple, effective, and non-invasive. Combination of several plasma miRNAs can increase both NPC diagnostic sensitivity and specificity.

miR-26a inhibits invasion and metastasis of nasopharyngeal cancer by targeting EZH2

Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic type of cancer that is widely prevalent in Southern China. Studies have shown that several microRNAs (miRNAs) are implicated in NPC metastasis. Our previous studies have demonstrated that miRNA miR-26a inhibits cell growth and tumorigenesis of NPC through the repression of enhancer of zeste homolog 2 (EZH2). However, the role of miR-26a in NPC metastasis remains unknown. In this study, we showed that ectopic expression of miR-26a inhibited the migratory and invasive capacities of NPC cells in vitro. Additionally, we used a murine model to investigate the role of miR-26a in NPC metastasis and results showed that miR-26a overexpression suppresses the metastatic behavior of NPC cells in vivo. Furthermore, the data demonstrated that miR-26a decreased the expression levels of EZH2 in vitro and in vivo, suggesting that the antimetastatic effect of miR-26a in NPC was mediated by regulating EZH2. Therefore, these findings indicate that miR-26a functions as an antimetastatic miRNA in NPC and that its antimetastatic effects are mediated mainly by repressing EZH2 expression.

[Inhibition of Plasmodium yoelii circumsporozoite protein on the activation of nuclear transcription factor in hepatoma cells stimulated by TNF-alpha]

OBJECTIVE

To investigate on the effect of Plasmodium yoelii (BY265 strain) circumsporozoite protein (CSP) on the activation of nuclear transcription factor KB (NF-KB) in hepatoma cells (HepG2) stimulated by TNF-alpha.

METHODS

Entire coding sequence of CSP was reverse transcribed and amplified by RT-PCR with sporozoite total RNA as template, then cloned into pFLAG-CMV8 for construction of the recombinant plasmid pFLAG-CMV8-CSP. Indirect immunofluorescence staining with rabbit anti-CSP was applied to verify the expression and distribution of FLAG-CSP fusion protein in HepG2. Three groups were established for the experiment: group A with HepG2 transfected by pFLAG-CMV8 as negative control, group B with HepG2 transfected by pFLAG-CMV8 and stimulated by 100 ng/ml TNF-alpha, and group C with HepG2 transfected by pFLAG-CMV8-CSP and stimulated by 100 ng/ml TNF-alpha. Dual-luciferase assay and EMSA were performed to detect the nuclear translocation and activation of NF-kappaB, to observe if pFLAG-CMV8-CSP suppressed the activation of NF-KB in HepG2 stimulated by TNF-alpha.

RESULT

The expression of pFLAG-CMV8-CSP was localized on cytoplasm of HepG2. The activity ratio of firefly luciferase to Renilla luciferase in group C (0.228 +/- 0.029) was significantly lower than both groups A (0.438 +/- 0.085) and B (0.571 +/- 0.030) (P < 0.05). EMSA showed that the band in group C was significantly weaker than group B.

CONCLUSION

Plasmodium yoelii CSP localizes in the cytoplasm of HepG2 and inhibits the activation and nuclear translocation of NF-kappaB in HepG2 stimulated by TNF-alpha.

[Recombinant Plasmodium yoelii expressing green fluorescent protein in erythrocytic and mosquito stages]

OBJECTIVE

To generate recombinant Plasmodium yoelii BY265 strain which can express green fluorescent protein (GFP) in erythrocytic and mosquito stages.

METHODS

Recombinant plasmid containing P. berghei ssu-rrna and GFP genes were linearized by Sac II. The linearized plasmid was introduced into the erythrocytic stage of P. yoelii by electroporation. Kunming mice were infected with the recombinant parasites. After 24-30 hours post-infection, mice were treated with 70 microg/ml of pyrimethamine intraperitoneally for 5-6 d, and tail vein blood was then collected to make smear for parasite count. The parasites were examined by PCR. Anopheles stephensi mosquitoes were used to bite mice infected with the recombinant parasite. At the 7th and 16th day after the bite, oocyst development in mosquitoes was observed by fluorescence microscopy.

RESULTS

The recombinant parasites expressed GFP in erythrocytic stage, and the GFP and ssu-rrna genes were amplified by PCR in the recombinant parasites. The mosquito infection experiment showed a normal development of the recombinant parasites.

CONCLUSION

Transgenic P. yoelii BY265 strain has been established with stable expression of GFP in both erythrocytic and mosquito stages.

Correlation of histology with anorectal function following stapled hemorrhoidectomy

INTRODUCTION

The inadvertent removal of smooth muscle during the use of stapled hemorrhoidectomy had raised concerns about its effects on postoperative anorectal function. We correlated the amount of smooth muscle removed with anorectal function in the early postoperative period.

METHODS

Patients were assessed preoperatively with an Eypasch quality-of-life questionnaire and underwent anorectal manometry and physiology testing. This was followed by a similar examination at three months postoperatively. Patients were operated on by a single surgeon and the excised anorectal mucosa was sent for histologic examination. The amount of smooth muscle excised was expressed semiquantitatively as a percentage of the total tissue removed.

RESULTS

Sixty-eight patients (33 males) were recruited prospectively, with median age of 44 years. Six patients were lost to follow-up. Removal of anal transitional zone did not increase the incidence of incontinence. Both median preoperative and postoperative continence scores were good. Only one patient had incontinence to gas as a result of the operation. Median preoperative and postoperative quality-of-life scores were 114 and 131, respectively, out of a total of 144, the higher postoperative scores showing an improvement. Correlation of quality-of-life scores and mean resting anal pressures with percentage of smooth muscle removed did not show any statistical significance.

CONCLUSIONS

Some smooth muscle will invariably be excised in stapled hemorrhoidectomy but the amount of smooth muscle removed did not significantly affect the continence score, quality of life, or mean anal resting pressure after stapled hemorrhoidectomy. It remains a safe and preferred procedure for the treatment of hemorrhoids.

Minilaparotomy left iliac fossa skin crease incision vs. midline incision for left-sided colorectal cancer

BACKGROUND

Midline laparotomies offer excellent exposure but are associated with increased postoperative pain and longer recovery. A minilaparotomy resection of leftsided colorectal cancers was studied as an alternative approach.

PATIENTS AND METHODS

We performed a case-control retrospective review of 280 randomly selected patients (140 midline incisions; 140 left skin crease incisions) who underwent elective, curative resection of left-sided colorectal cancers.

RESULTS

Patients in both groups were of comparable age and sex. The left skin crease incision was shorter (median length, 13.5 cm) than the midline incision (median length, 20.0 cm). Median operation time was less in the left skin crease group (75 min) than in the midline incision group (105 min). Similar types of operations were performed, including left hemicolectomies, sigmoid colectomies, anterior resections and ultra-low anterior resections. Adequacy of resection was confirmed by histological analysis, with no involvement of margins. The median numbers of lymph nodes removed were comparable: 10 for the skin crease incision group and 12 for the midline incision group. Postoperative parameters for the skin crease incision group showed that feeding, ambulation, narcotic use and hospital stay were significantly better than the parameters in the midline group. Complications of intestinal obstruction were also reduced in the skin crease incision group.

CONCLUSIONS

The limited left skin crease incision provides adequate margins of clearance in colorectal cancers when compared to the midline incision, but has advantages of shorter operation time, earlier feeding and ambulation, and earlier discharge from hospital.

An anatomical study of the recurrent laryngeal nerve: its branching patterns and relationship to the inferior thyroid artery

The aim of this study was to provide information about the morphology and topography of the recurrent laryngeal nerve (RLN), its external features and branches, as well as its relationship to the inferior thyroid artery, the inferior horn of the thyroid cartilage and the thyroid gland. The RLNs in 50 adult cadavers (100 sides) were dissected and analyzed. A communicating loop connecting one branch of the RLN to another or a twig originating from the cervical sympathetic trunk was present in 13 of 100 sides. A double left RLN appeared in 2 sides; a right non-recurrent inferior laryngeal nerve appeared in one side. All of the RLNs, including looped ones, bifurcated into laryngeal branches and extralaryngeal branches, with most of the former further dividing into the anterior and posterior branches entering the larynx. The relations of the RLN to the inferior thyroid artery, the inferior horn of the thyroid cartilage and the thyroid gland were inconstant. The information gained from this study will be of value in thyroid surgery.

[Influence of IFN-alpha and IFN-alpha combined with GM-CSF on expression of the genes related to cell apoptosis of MNCs from bone marrow in CML patients]

OBJECTIVE

To investigate the effects of interferon-alpha(IFN-alpha) and IFN-alpha combined with granulocytic macrophage colony-stimulating factor(GM-CSF) on expression of bcr-abl, bcl-2 and c-myc genes in the mononuclear cells(MNCs) from bone marrow(BM) of the patients with chronic myelogenous leukemia at chronic phase(CML-CP).

METHODS

The MNCs were collected from bone marrow of 14 CML-CP patients by centrifugalization in lymphocyte-separation medium, and cultivated in the medium with IFN-alpha and IFN-alpha plus GM-CSF for 24 hours. The expression levels of bcr-abl, bcl-2, c-myc and beta-actin were detected by using relatively quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and optical density scanning technology for the amplified fragments. The statistical differences between each inducing experimental group and the control were analyzed by t-test in pairs.

RESULTS

Both IFN-alpha (200 U.ml-1) and IFN-alpha combined with GM-CSF (10 ng.ml-1) significantly inhibited bcr-abl gene expression, meanwhile IFN-alpha partially suppressed c-myc and bcl-2 gene expression, and GM-CSF significantly inhibited bcl-2 gene expression but partially upregulated bcr-abl and c-myc gene expression levels on the basis of IFN-alpha effects.

CONCLUSIONS

Both IFN-alpha and IFN-alpha plus GM-CSF can inhibit the expression of anti-apoptosis gene such as bcr-abl and bcl-2, and regulate the expression of c-myc. It is the possible mechanism of IFN-alpha therapy or combined therapy on CML at chronic phase that the malignant clone expansion is inhibited by promoting apoptotic cell death.

Fat intake in Hong Kong Chinese children

The people of Hong Kong are experiencing a transition in dietary practices and lifestyle that can be observed in the fat intakes of Hong Kong children as compared with those of their counterparts on mainland China. The studies described here include 1) a longitudinal and observational dietary survey beginning with a cohort of 174 newborns and concluding with 124 children at age 7 y; 2) a biochemical study of serum lipids in relation to dietary fat intake at age 7 y; 3) a chemical fatty acid analysis and comparison of duplicate meals collected from 20 Hong Kong and 20 mainland Chinese children at age 7 y; 4) a dietary assessment of 52 lactoovovegetarian children aged 4-14 y; and 5) a comparison of the growth of all subjects with US National Center for Health Statistics standards. About 30% of the total daily energy intake of Hong Kong Chinese children aged 1-7 y was contributed by fat-much more than that in the traditional Chinese diet. Growth of the children was not impaired, including that of children on the mainland and of those lactoovovegetarians in Hong Kong whose fat intakes were lower. Mean serum cholesterol of Hong Kong Chinese children at age 7 y was 4.59 mmol/L, significantly higher than that of their counterparts on the mainland, 4.16 mmol/L. Foods consumed in Hong Kong had a significantly lower ratio of 18:2 to 14:0. Nutritional deficiency was uncommon. Chinese children in Hong Kong had a dietary fat intake that was both quantitatively and qualitatively different from the traditional Chinese diet.

Serum fatty acid, lipid profile and dietary intake of Hong Kong Chinese omnivores and vegetarians

OBJECTIVE

To examine the serum fatty acid and lipid profiles and dietary intake of Hong Kong Chinese omnivores and vegetarians with respect to cardiovascular health.

DESIGN

Random population survey stratified by age and sex.

SUBJECTS

One-hundred and ninety-four omnivore subjects (81 men, 113 women) age 25-70 y, and 60 ovo-lacto-vegetarian adults (15 men, 45 women) age 30-55 y.

MEASUREMENTS

Nutrient quantitation was by a food frequency method. Serum fatty acids were analysed by gas chromatography, and serum lipid by standard laboratory methods.

RESULTS

Compared with omnivores, vegetarians had higher serum concentrations of polyunsaturated (PUFA) and monosaturated fatty acids (MUFA), and lower saturated fatty acids (SFA), long chain omega-3 and trans fatty acids (TFA). They also had lower serum cholesterol and higher apoA-1 concentrations, but the LDL/HDL ratio was not different. The ratio of polyunsaturated to saturated fatty acids intake was higher in vegetarians. Compared with results from populations with higher incidences of coronary heart disease, while lower myristic and palmitic acid concentrations and higher eicosapentaneoic (EPA) and docosahexanoic acid (DHA) may partly account for the difference in incidence, linoleic acid concentration was higher. Although the Chinese vegetarian diet may be beneficial for heart health in that antioxidant and fibre intakes are higher and saturated fat lower, the low EPA and DHA due to omission from dietary source and suppressed formation by high linoleic acid level, and the presence of TFA in the diet, may exert an opposite effect.

CONCLUSION

There are some favourable features in the serum fatty acid profile in the Hong Kong Chinese population with respect to cardiovascular health, but the consumption of TFA is of concern. The Chinese vegetarian diet also contains some adverse features.

[Preliminary report on immunoscreening of Schistosoma japonicum adult worm cDNA library by sera from infected Microtus fortis]

Microtus fortis (Mf) is resistant to Schistosoma japonicum (Sj) infection. To explore if Mf responses to special Sj antigens after infection, Sj adult worm cDNA library was screened with sera from infected Mf. Twelve positive clones were obtained after rescreening. After automatically excised with the helper phage, positive clones were further identified by PCR. The size of Sj cDNA fragments in positive clones ranged from 300 bp to 1.8 kb. Six of these fragments were 300 bp, one was 1 kb, and five were 1.8 kb in size. The results indicate that the infected Mf serum could recognize Sj specific antigens. It is valuable to further study the immune protection of these cloned molecules.

[Determination of vitamin D2 included with beta-cyclodextrin complex in "longmu zhuanggu chongji" by HPLC]

In order to enhance the stability of vitamin D2(VD2), the inclusion complex of VD2 with beta-cyclodextrin(beta-CD) was added in "Longmu Zhuanggu Chongji", a medicine of children for the prevention and cure of rickets. The VD2 in beta-CD-VD2 inclusion complex was satisfactorily determined by both reversed-phase high performance liquid chromatography(HPLC) and ultraviolet spectrometry(UV). The experimental results from UV were in well consistent with those from HPLC. The accuracy and recovery of HPLC measurement were analyzed, and their relative standard deviation(RSD) were given to be 0.63% and 1.54%, indicating the method is quite correct and reliable, and the linear regression equation is reasonable. The "Longmu Zhuanggu Chongji" containing beta-CD-VD2 inclusion complexes was saponified by a mixture of KOH, vitamin C (VC) and alcohol-water(1:2, V/V) at 70 degrees C, then extracted with petroleum ether. An accurate content of the VD2 product was obtained by HPLC. A simple and rapid HPLC method, which can detect VD2 in the inclusion complex and in "Longmu Zhuanggu Chongji", has been established in this work.

Body fatness and serum lipids of 11-year-old Chinese children

It has been suggested that distribution of body fat has a stronger bearing on health risk than total body fat. Magnetic resonance imaging (MRI) was used to examine the distribution of fat and correlated with body fat assessed by the usual clinical methods-weight, weight-for-height, body mass index (BMI), triceps and subscapular skinfold thickness in 11-y-old Chinese children. Lipid profiles were used as indicators for coronary risk. Eighty-eight subjects had body fat distribution estimated by MRI, while 49 had serum lipids measured. Anthropometric parameters correlated significantly with total fat at the umbilical level measured by MRI (weight: r = 0.90 in boys, 0.75 in girls; BMI: r = 0.94 in boys, 0.87 in girls; percent median weight-for-height: r = 0.90 in boys, 0.79 in girls, triceps skinfold thickness: r = 0.89 in boys, 0.90 in girls; subscapular skinfold thickness: r = 0.93 in boys, 0.88 in girls). Obese subjects had proportionally less visceral fat than subcutaneous fat at umbilical level. Using stepwise multiple regression, predictive factors for high-density lipoprotein cholesterol were BMI in boys and breast-staging in girls. For triglycerides, it was genital staging in boys and for total cholesterol, it was breast-staging in girls. Visceral fat was not a significant determinant of serum lipids.

Body fat estimation in children by magnetic resonance imaging, bioelectrical impedance, skinfold and body mass index: a pilot study

OBJECTIVE

The aim of this study was to identify the clinical method to estimate body fat which gave best correlation of total body fat and percentage body fat as measured on MRI.

METHODS

Magnetic resonance imaging (MRI) was used to estimate the total body fat volume and percentage body fat and this was compared with assessment by bioelectrical impedance (BEI), skinfold thickness and body mass index (BMI) in 8- to 12-year-old children.

RESULTS

Total body fat measured on magnetic resonance imaging (TBF-MRI) significantly correlated with body mass index, triceps and subscapular skinfolds, and percentage body fat estimations by BEI. Multiple regression analysis showed that BMI and BEI together gave the best prediction of total body fat as measured on MRI from the equation: TBF-MRI=-25277.77+1457.61(BMI)+423.95(%fat-BEI), with R2=0.89. Percentage body fat measurement from MRI, BEI and skinfold were not significantly different but their results were not interchangeable. Linear regression of %body fat from MRI on those obtained from BEI and skinfold measurements showed a modest fit with R2=0.6973 and 0.5501, respectively.

CONCLUSIONS

In children 8-12 years old, BMI gives a good estimation of the total body fat as measured on MRI. The estimation will be improved when both BEI and BMI are used in the prediction. Bioelectrical impedance has a low correlation with total body fat and its use alone in estimating total body fat is not recommended. Skinfold measurement also gives a reasonably good prediction of total body fat and addition of BMI and BEI does not improve the prediction. Both BEI and skinfold measurements give a modest prediction of %body fat measured by MRI method.

Production of granulocyte-macrophage colony-stimulating factor by T cells is regulated by B7 and IL-1 beta

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has proliferation- and differentiation-inducing effects on immature myeloid cells in the bone marrow, and it can modulate the function of several types of mature myeloid cells. We have stimulated purified human T cells with immobilized anti-CD3 or mitogenic anti-CD2 (a combination of monoclonal antibodies 9-1 and 9.6) which could induce GM-CSF production. The cytokines interleukin-1 beta (IL-1 beta) and IL-2 strongly enhanced GM-CSF production, while IL-4, IL-6, GM-CSF, interferon-gamma (IFN-gamma) and tumour necrosis factor (TNF) had no effect. Activation of protein kinase C by phorbol myristate acetate or triggering of CD28 on T cells by monoclonal antibody 9.3 provided accessory signals for enhanced GM-CSF production in activated T cells. Most important, the addition of mouse cells transfected with human B7-1 (CD80), a natural ligand for CD28, provided a potent accessory signal for GM-CSF production by activated T cells, which could not be blocked by cyclosporin A. The effect of IL-1 beta was in fact indirect, and resulted from enhanced IL-2 production, while the effect of B7 resulted from both IL-2-dependent and IL-2-independent pathways. We conclude that antigen-presenting cells (APC) can up-regulate GM-CSF production through IL-1 beta and through CD28 triggering by B7 molecules. As GM-CSF itself up-regulates B7 expression and IL-1 beta production by APC, a bidirectional regulatory feedback pathway between APC and T cells seems to modulate GM-CSF production.

Insulins from different species--chicken and snake

We have worked out a new adsorption method for the preparation of insulins from different species. At present, we are mainly involved in chicken and snake insulins. In all insulins so far studied, only chicken insulin has been reported to have much higher activity. However, results from different laboratories are quite different from one another. We have obtained chicken insulin in typical rhombohedral crystalline form and determined its activity in vivo which is not appreciably different from that of porcine insulin. From the pancreas of a non-venomous snake, Zaocys dhumnades dhumnades (Cantor), we have prepared snake insulin which is different from rattle snake insulin reported earlier. The dodecahedral crystals of the snake insulin are similar to those of zinc-free porcine insulin.