[The role of Müller cells in the formation and development of macular hole]

Müller cells are important glial cells in the retina, which play important roles in maintaining the stability of the retina by mechanical support, homeostasis, and physiological metabolism, as well as protecting photoreceptor cells and retinal pigment epithelial cells. The degeneration and destruction of Müller cells are often accompanied by various retinal diseases, and the function of Müller cells is changed under pathological conditions. Based on the summary of the morphology, distribution and function of Müller cells, this article analyzes the different manifestations and changes of Müller cells in different stages of macular hole and the closely related mechanisms, aiming to clarify the role of Müller cells in the formation and development of macular hole and to provide reference for the prediction of disease progression and guidance of treatment.(This article was published ahead of print on the official website of Chinese Journal of Ophthalmology on Augest 28, 2023).

Salvage endoscopic surgery for skull base osteoradionecrosis in nasopharyngeal carcinoma patients: A prospective, observational, single-arm clinical study

BACKGROUND

Postradiation skull base osteoradionecrosis (ORN) is a severe complication that occurs after radiotherapy in patients with nasopharyngeal carcinoma (NPC) that can severely affect quality of life (QOL) and be life threatening. Only 13.4% - 28.6% of patients can be cured by traditional repeated endoscopic debridement. Here, we introduced salvage endoscopic surgery for skull base ORN patients and evaluated its clinical efficacy.

METHODS

This was a prospective, observational, single-arm clinical study. Clinical data from 18 skull base ORN patients who underwent radical endoscopic necrectomy followed by reconstruction using a septal pedicled mucosal flap or temporal muscle flap were included in the study. The endpoint was an overall survival (OS) of 2 years. The numeric rating scale (NRS) scores for pain and foul odor were analyzed to determine the efficacy and safety of this surgery.

RESULTS

A total of 21 patients were recruited, 18 of whom completed the study and were analyzed. All surgeries were successfully performed. During the 2-year study, the OS rate of the entire cohort was 75%. The median NRS score for pain decreased from 6.44 +- 2.62 to 0.50 +- 0.71, and the NRS score for foul odor decreased from 1.89±1.08 to 1 after surgery.

CONCLUSIONS

Salvage endoscopic necrectomy followed by construction using a septal pedicled mucosal flap or temporal muscle flap is a novel, safe, and effective treatment for ORN in patients with NPC.

CLINICAL TRIAL REGISTRATION

This study was approved by the independent ethics committee of the Eye, Ear, Nose and Throat Hospital of Fudan University (IEC No. 2019095-1). Written informed consent was obtained from all patients. The study was registered with the Chinese Clinical Trial registry (ChiCTR2000029327).

[Establishment of contralateral arteriovenous fistula by using the waste vein on the side of central venous lesion: a case report]

Central venous lesion is a difficult problem in the vascular access complications of hemodialysis, which can cause serious clinical symptoms and affect the quality of hemodialysis and life of patients. We established arteriovenous fistula of the contralateral graft blood vessel with the used vein on the diseased side of the central vein of the patient. The arteriovenous fistula of the graft blood vessel was successfully punctured and hemodialysis was performed 2 weeks later. In this way, we not only solved the problem of venous hypertension and subsequent vascular access in the patient, but also reserved more vascular resources.

[Efficacy and safety of neoadjuvant toripalimab combined with nimotuzumab and chemotherapy in patients with unresectable stage Ⅳ squamous cell carcinoma of penis]

Objective: To compare the efficacy and safety of neoadjuvant chemotherapy alone or combined with toripalimab and nimotuzumab in patients with unresectable locally advanced or metastatic squamous cell carcinoma of penis. Methods: A total of 33 patients with unresectable squamous cell carcinoma of penis undergoing neoadjuvant chemotherapy alone or combined with toripalimab and nimotuzumab at Sun Yat-sen University Cancer Center from May 2015 to June 2021 were enrolled retrospectively. All the patients were male, with a median age (M(IQR))of 49.0 (13.5) years (range: 30 to 70 years). According to the therapy protocols, patients were divided into the chemotherapy group (16 cases) and the triple combination group (17 cases). Log-rank test was used to compare the progression-free survival and overall survival. χ² test or Fisher exact method was used to compare the objective response rate, pathological down-stage rate and adverse events between these two groups. Results: The follow-up time was 28.1(19.2) months (range: 1.5 to 33.4 months). Patients of triple combination group were observed significantly longer progression-free survival (30.0 months vs. 8.2 months, χ²=3.998, P=0.046) than those of chemotherapy group. The median overall survival of the triple combination group and chemotherapy group were not reached and 15.2 months (χ²=3.298, P=0.069), respectively. Although there was no significant difference in the subsequent surgical resection rate between these two groups (12/17 vs.11/16, P=1), the objective response rate and the pathological complete response rate in triple combination group were significantly higher than in chemotherapy group (13/17 vs. 6/16, χ²=5.125, P=0.024; 6/7 vs. 0, P=0.001). The main common grade 1 to 2 adverse events in the triple combination group were alopecia (16 cases), anemia (15 cases), and nausea (14 cases). The main common grade 1 to 2 adverse events in the chemotherapy group were anemia (14 cases), alopecia (12 cases), decreased appetite (12 cases), and nausea (11 cases). The incidence of adverse events ≥grade 3 was similar in the triple combination group and chemotherapy group (8/17 vs. 6/16, χ²=0.308, P=0.579). There was no grade 3 adverse event in both groups. Conclusion: Compared with traditional chemotherapy alone, chemotherapy combined with toripalimab and nimotuzumab provides longer progression-free survival and similar toxicity for unresectable stage Ⅳ squamous cell carcinoma of penis.

Autophagy deficiency promotes lung metastasis of prostate cancer via stabilization of TWIST1

PURPOSE

The role of autophagy in prostate cancer metastasis remains controversial, and the effects of the autophagy-related gene ATG5 on prostate cancer metastasis are poorly understood. This study aims to explore the effects of ATG5 on prostate cancer metastasis and its molecular mechanism.

METHODS

The metastatic characteristics of LNCaP and DU145 cells were assessed by NOD/SCID mouse experiments, western blot, transwell assay, and wound-healing assay. Double membrane autophagic vesicle observation and the adenovirus-expressing mCherry-GFP-LC3B fusion protein were used to assess the autophagic characteristics of LNCaP and DU145 cells. The role of p62 in the accumulation of TWIST1 was confirmed by western blot under different conditions. The lentivirus particles of shATG5, NOD/SCID mice experiments, western blot, transwell assay, and wound-healing assay were used to confirm the role of ATG5 in TWIST1 accumulation and prostate cancer cell metastasis.

RESULTS

We identified a stabilizing effect of p62 on TWIST1 in the autophagic regulation of EMT and prostate cancer metastasis. The loss of ATG5 in DU145 cells resulted in autophagy deficiency and p62 accumulation, which stabilized TWIST1 and increased the TWIST1 level in prostate cancer cells, and eventually promoted EMT and metastasis. In comparison, LNCaP cells with regular ATG5 expression and autophagy status retained remarkable epithelial cell characteristics and had limited metastatic characteristics. Similar results were also found in wild-type LNCaP cells and LNCaP cells with stable ATG5 interference.

CONCLUSIONS

Our research revealed ATG5-mediated autophagy as a key mechanism that controls the metastasis of prostate cancer by regulating p62 abundance and TWIST1 stabilization.

[Research progress of autoantibodies in primary biliary cholangitis]

Primary biliary cholangitis (PBC) is a chronic, progressive, intrahepatic cholestasis disease. Its occurrence and development are accompanied by changes in the titer of autoantibodies. However, its pathogenesis, extent of autoantibody changes and their effects are not yet fully understood. Therefore, there is a lack of effective methods for early diagnosis of PBC in patients. Finding specific PBC autoantibody markers will greatly improve the diagnostic efficiency and save early treatment time, thereby improving therapeutic effect and prognosis. This article summarizes several PBC-related serum autoantibody markers.

Correlation study between the magnetic resonance imaging features of breast cancer and expression of immune molecular subtypes

OBJECTIVE

To investigate the correlation between breast cancer magnetic resonance imaging features and immune molecular subtypes.

PATIENTS AND METHODS

A total of 129 breast cancer patients were selected as the research object. All the patients were diagnosed by histopathology. All of them had breast magnetic resonance imaging and examination data of immunohistochemical (IHC) ER, PR, HER-2, and Ki-67. The correlation of breast cancer magnetic resonance imaging features with different immune molecular subtypes was retrospectively analyzed.

RESULTS

Breast cancer is divided into different molecular subtypes. There were 72 cases with Luminal A type (55.81%), 20 cases with Luminal B type (15.50%), 14 cases with HER-2+ type (HER-2 type for over-expression) (10.85%), 23 cases with TNBC type (ER, PR and HER-2 were negative) (17.84%). The magnetic resonance imaging features of breast cancer were included, the post-enhanced morphology, margins, internal enhancement features, time-signal intensity curve (TIC) and molecular subtype expression of lesions were significantly correlated with the immune molecular subtypes (C=0.602, 0.439, 0.350 and 0.407, p=0.000, 0.000, 0.006 and 0.000). Lesion morphology: Luminal A type was mainly oval, accounting for 76.39% (55/76). Luminal B type and HER-2+ type was mainly irregular, accounting for 75.00% (15/20) and 64.29% (9/14) respectively. TNBC type was mainly shown as lobulation, accounting for 60.87% (14/23). Margin of the lesion: Luminal A type was mainly smooth margin, accounting for 73.61% (53/72). Luminal B type and TNBC type were mainly irregular margin, accounting for 70.00% (14/20) and 56.52% (13/23) respectively. The margin of HER-2+ type was mainly spiculation, accounting for 64.29% (9/14). The internal enhancement features: Luminal A type was mainly even enhancement, accounting for 62.50% (45/72). Luminal B type and HER-2+ type were mainly heterogeneous enhancement, accounting for 65.00% (13/20) and 64.29% (9/14) respectively. TNBC type was mainly annular enhancement, accounting for 73.91% (17/23). TIC type: Luminal A type was mainly Type II, accounting for 66.67% (48/72). Luminal B, HER-2+ type and TNBC type was mainly Type III, accounting for 70.00% (14/20), 64.29% (9/14) and 60.87% (14/23) respectively. The clinical signs include painless breast lumps, bloody breast discharge, and orange peel-like skin changes, nipple retraction and nipple elevation. There is no significant correlation between the above signs and the expression of molecular subtypes (C=0.014, 0.129, 0.154, 0.097 and 0.057, p=0.999, 0.533, 0.447, 0.747 and 0.935 respectively), the difference is not statistically significant (p>0.05).

CONCLUSIONS

The characteristics of breast cancer magnetic resonance imaging was certainly correlated with the expression of immune molecular subtypes. The breast cancer molecular subtypes can be predicted by the imaging signs, which can provide valuable information for preoperative neoadjuvant treatment of breast cancer.

[Cost-effectiveness of primary prophylaxis with PEG-rhG-CSF in early-stage breast cancer patients receiving chemotherapy in China]

Objective: To evaluate the cost effectiveness of primary prophylaxis (PP) with pegylated recombinant human granulocyte colony stimulating factor (PEG-rhG-CSF), PP with recombinant human granulocyte colony stimulating factor (rhG-CSF) and no prophylaxis in women with early-stage breast cancer in China. Methods: Two phase Markov models were constructed for a hypothetical cohort of patients aged 45 with stage Ⅱ breast cancer. The first phase modelled costs and outcomes of 4 cycles docetaxel combined with cyclophosphamide [TC×4, febrile neutropenia (FN) risk>20%] chemotherapy, which assumptions based on literature reviews, including FN rates [base-case (deterministic sensitivity analysis range), 0.29 (0.24-0.35)] and related events [FN case-fatality, 3.4 (2.7-4.1)]. Second phase modelled the long term survival which was link with the relative dose intensity (RDI) [mortality hazard ratio (HR) of RDI < 85% vs ≥85%, 1.45 (1.00-2.32)]. Clinical effectiveness, therapeutic costs, and economic utilities were estimated from peer-reviewed publications and expert opinions in case of unavailability of published evidences. Results: Compared to rhG-CSF PP and no prophylaxis, the cost of PEG-rhG-CSF PP increased to 5 208.19 RMB and 5 222.73 RMB, respectively. The quality-adjusted life-years (QALYs) enhanced to 0.066 and 0.297, respectively. Accordingly, the incremental cost effectiveness ratios (ICERs) are 79 146.3 RMB and 17 558.77 RMB per QALY, which were both below the willingness to pay (WTP) threshold of three times GDP per capita (18, 000 RMB) recommended by the WHO. Sensitivity analysis suggested that the more clinically effective the primary prophylaxis with PEG-rhG-CSF is, the more cost-effective primary prophylaxis with PEG-rhG-CSF will be. And the lower the mortality HR of RDI<85% vs ≥85% is, the more cost-effective primary prophylaxis with PEG-rhG-CSF will be. Conclusion: Although the cost of PP PEG-rhG-CSF is higher, considering the additional benefits, the administrating of PP PEG-rhG-CSF is likely to be a cost-effective alternative to PP rhG-CSF and no prophylaxis in patients with early stage breast cancer whose FN risks are more than 20% in China.

Circ-CCDC66 accelerates proliferation and invasion of gastric cancer via binding to miRNA-1238-3p

OBJECTIVE

The aim of this study was to examine the expression of circ-CCDC66 in gastric cancer (GC) tissues and cell lines, as well as its correlation with the prognosis of GC. Moreover, the regulatory effects of circ-CCDC66 on biological behaviors of GC cells and its molecular mechanism were explored.

PATIENTS AND METHODS

The relative expression level of circ-CCDC66 in GC tissues and cell lines was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between the circ-CCDC66 level and overall survival of GC patients was analyzed as well. The potential influences of circ-CCDC66 on proliferative and invasive abilities of GC cells were evaluated through 5-Ethynyl-2'-deoxyuridine (EdU), colony formation and transwell assay, respectively. Meanwhile, the cell cycle progression and apoptosis of GC cells affected by circ-CCDC66 were determined. In addition, the direct target miRNA of circ-CCDC66 was predicted and verified by bioinformatics method and Dual-Luciferase reporter gene assay, respectively.

RESULTS

Circ-CCDC66 was significantly up-regulated in GC tissues and cell lines. Up-regulation of circ-CCDC66 indicated markedly worse prognosis of GC patients. Transfection of circ-CCDC66-siRNA remarkably attenuated proliferative and invasive abilities of BGC-823 and MGC-803 cells. Besides, GC cells were arrested in the G0/G1 phase, and the apoptotic rate was remarkably elevated after circ-CCDC66 knockdown. The Dual-Luciferase reporter gene assay verified that circ-CCDC66 bind to miRNA-1238-3p by competing with LHX2 (LIM-homeobox domain 2). MiRNA-1238-3p was significantly down-regulated in GC cells, whereas LHX2 was up-regulated. Furthermore, overexpression of miRNA-1238-3p in GC cells markedly suppressed the LHX2 level.

CONCLUSIONS

Circ-CCDC66 is highly expressed in GC tissues and cell lines. Knockdown of circ-CCDC66 attenuates proliferative and invasive abilities of GC cells. Our results indicate that circ-CCDC66/miRNA-1238-3p/LHX2 axis may be a promising target for GC treatment.

Expression of miR-1294 is downregulated and predicts a poor prognosis in gastric cancer

OBJECTIVE

MicroRNAs (miRNAs) play critical roles in regulating tumor development and progression. The aim of the study is to investigate the clinical significance of miR-1294 expression in gastric cancer (GC).

PATIENTS AND METHODS

The expression of miR-1294 in 82 cases of GC tissues and adjacent normal tissues was determined using quantitative Real Time-PCR (qRT-PCR) analyses. Survival plot was calculated using the Kaplan-Meier methods and log-rank test from the date of operation to the time of death or last follow-up date. The association between miR-1294 expression and clinical categorical data was analyzed using the chi-squared test. Moreover, Univariate and multivariate Cox analysis were performed to assess the risk factors of GC prognosis.

RESULTS

We showed that miR-1294 expression was significantly downregulated in GC tissues compared to adjacent normal tissues. The low expression of miR-1294 in patients with GC was correlated with clinicopathological parameters including larger tumor size, lymph node metastasis, and distant metastasis. Kaplan-Meier survival analysis showed that GC patients with lower miR-1294 expression exhibited a shorter disease-free survival (DFS) and overall survival (OS) time compared to those patients with higher miR-1294 expression. Multivariate Cox analysis showed that lower miR-1294 expression, tumor size, lymph node metastasis, and distant metastasis were identified as independent risk factors of GC prognosis.

CONCLUSIONS

Our results provided evidence that miR-1294 expression was significantly downregulated in GC and may serve as a predictor of GC prognosis.

[Clinical outcomes with cruciate-substituting ultra-congruent and posterior stabilized in total knee arthroplasty]

Objective: To investigate clinical outcomes of total knee arthroplasty with ultra-congruent insert(UC) or posterior stability insert (PS). Methods: A retrospective study was performed on 97 patients (17 males, 80 females, 119 knees) with knee osteoarthritis who received total knee arthroplasty. Of the patients, 42 cases (50 knees) received UC protheses and 55 cases (69 knees) received PS protheses in total knee arthroplasty by the same surgeon in Peking University Third Hospital from March 2015 to November 2015. The data including age, gender, body mass index (BMI), range of motion (ROM), Western Ontario and McMaster Universities (WOMAC) osteoarthritis index and Hospital for Special Surgery Knee Score (HSS) before and after the surgery were collected and compared in the two groups. The data were compared between the two groups by single-sample t test. Results: There was no significant differences in age, gender, BMI, ROM, HHS and WOMAC scores between the two groups before operation(all P>0.05). At 3 months and 2 years of follow-up, ROM, HSS and WOMAC scores were significantly improved in the two groups(all P<0.05), but there was no statistical difference between the two groups(t=-0.303, -1.593, Z=-0.500, all P>0.05). One patient with PS prosthesis recieved revision surgery due to prothesis loosening; and no complication found in the UC group(χ(2)=0.731, P>0.05). Conclusion: There is no obvious difference between PS and UC in TKA, UC insert seems to be a practical alternative to the PS.

[Lung function influenced the prognosis of cardiac surgery in patients with chronic obstructive pulmonary disease]

Objective: To investigate the value of lung function for the prognosis of cardiac surgery in patients with chronic obstructive pulmonary disease(COPD). Methods: A retrospective analysis was conducted on the hospitalized patients with coronary heart disease or valvular heart disease in Beijing Anzhen hospital during Janury 2013 to December 2015. The relationship between lung function and extubation time, time of staying in ICU, second time tracheal incubation, tracheotomy and mortality rate were analyzed. Results: There were 355 patients without surgery in a total 1 729 of patients, of which 65 (18.31%)suffered from severe pulmonary dysfunction. There were 242 patients with obstructive ventilation dysfunction, 75 with mild, 127 with moderate, and 40 with severe and very severe obstructive ventilation dysfunction. There were significant differences in the rates of planned extubation and late extubation between patients with normal lung function (81.6% and 10.7%) and those with abnormal lung function(74.4% and 12.8%). In patients with different GOLD classification (Ⅰ, Ⅱ, and Ⅲ-Ⅳ), there were significant differences in the rates of early extubation 14.7%, 14.2% and 5%, planned extubation (80%, 74% and 65%) and late extubation (5.3%, 11.8% and 30%). By comparison with patients without COPD, the extubation time of COPD patients increased by 20.3%, the time of staying in ICU prolonged by 14.2%, and the mortality rate increased to 180%(P<0.05). However, there was no significant difference in the rate of second time tracheal incubation or tracheotomy. Conclusion: There was a close relationship between GOLD classification and prognosis of cardiac surgery patients with COPD. Cardiac surgery needs to be cautious because of increase in incidence of postoperative adverse events in patients with severe pulmonary dysfunction.

Evaluation of a loop-mediated isothermal amplification assay based on hrpZ gene for rapid detection and identification of Pseudomonas syringae pv. lachrymans in cucumber leaves

AIMS

Cucumber angular leaf spot caused by Pseudomonas syringae pv. lachrymans (Psl) is an important and destructive disease worldwide, and no effective technique has been developed for the control of the pathogen. Detection of infection or latent in cucumber plants is critical to evaluate disease progress and strengthening management to avoid a serious epidemic in the fields. In this paper, we developed a rapid and sensitive method for detection of Psl using an isothermal method known as loop-mediated amplification (LAMP).

METHODS AND RESULTS

A set of six primers was designed to amplify the gene coding for the hrpZ, and conditions for detection were optimized to complete in 60 min at 67°C, and the amplification were confirmed through gel electrophoresis or visually inspected using calcein stain. The specificity of LAMP primers set was widely validated on Psl and nontarget strains. In sensitivity testing, LAMP allowed detection as low as 10⁴  CFU per ml bacterial cells without DNA extraction. The novel method was also applied for detecting Psl in infected cucumber leaves, and even the early onset of disease can be detected by the assay.

CONCLUSIONS

This study confirmed that the novel developed LAMP assay is an easy, rapid and sensitive method for the detection of Psl in infected leaves.

SIGNIFICANCE AND IMPACT OF THE STUDY

The method is suitable for direct detection of Psl without strain enrichment and complex DNA extraction from samples in the field, and hence it has the capability to be used for on-site disease diagnosis and field surveys.

Assessing cadmium and vanadium accumulation using diffusive gradient in thin-films (DGT) and phytoplankton in the Churchill River estuary, Manitoba

Diffusive gradient in thin films (DGT) and phytoplankton communities were evaluated for the measurement of Cd and V at environmentally relevant concentrations in laboratory settings and in the Churchill River estuary (Manitoba, Canada) during an annual spring melt. Despite rapid changes in hydrology and water quality, DGT samplers and intracellular Cd and V concentrations were positively correlated (0.79 < r(2) < 0.99), suggesting comparable accumulation trends between both DGT-labile and intracellular monitoring techniques. The largest accumulated concentrations of both Cd and V by DGT and phytoplankton accumulation methods were found later into the river discharge period. In controlled settings, accumulated Cd and V concentrations by the diatom Attheya septentrionalis displayed a strong correlation with metals accumulated by DGTs (r(2) > 0.99). Principal component analysis (PCA) reinforced similarities between both metal monitoring techniques and assessed how changing environmental variables during the river discharge period influenced each monitoring technique. Cd accumulation was influenced by DOC concentrations and protein-like DOM whereas ionic strength (i.e. conductivity) and humic-like DOM influenced V accumulation. The present findings suggest that (1) DGT is a versatile tool for monitoring bioaccumulation of Cd and V in highly dynamic environmental systems and (2) DOC concentration, DOM composition, conductivity, pH, and river discharge influence the bioavailability of Cd and V in estuarine and riverine waters.

Evaluation of bone matrix gelatin/fibrin glue and chitosan/gelatin composite scaffolds for cartilage tissue engineering

This study was designed to evaluate bone matrix gelatin (BMG)/fibrin glue and chitosan/gelatin composite scaffolds for cartilage tissue engineering. Chondrocytes were isolated from costal cartilage of Sprague-Dawley rats and seeded on BMG/fibrin glue or chitosan/gelatin composite scaffolds. After different in vitro culture durations, the scaffolds were subjected to hematoxylin and eosin, Masson's trichrome, and toluidine blue staining, anti-collagen II and anti-aggrecan immunohistochemistry, and scanning electronic microscopy (SEM) analysis. After 2 weeks of culture, chondrocytes were distributed evenly on the surfaces of both scaffolds. Cell numbers and the presence of extracellular matrix components were markedly increased after 8 weeks of culture, and to a greater extent on the chitosan/gelatin scaffold. The BMG/fibrin glue scaffold showed signs of degradation after 8 weeks. Immunofluorescence analysis confirmed higher levels of collagen II and aggrecan using the chitosan/gelatin scaffold. SEM revealed that the majority of cells on the surface of the BMG/fibrin glue scaffold demonstrated a round morphology, while those in the chitosan/gelatin group had a spindle-like shape, with pseudopodia. Chitosan/gelatin scaffolds appear to be superior to BMG/ fibrin glue constructs in supporting chondrocyte attachment, proliferation, and biosynthesis of cartilaginous matrix components.

ERK1/2/p53 and NF-κB dependent-PUMA activation involves in doxorubicin-induced cardiomyocyte apoptosis

OBJECTIVE

Numerous studies have demonstrated that Doxorubicin (DOX) induces cardiomyocyte apoptosis, which is associated with DOX-induced acute and chronic cardiotoxicity. DOX activated ERP1/2 and NF-KB signals has been linked to DOX-induced apoptosis and cardiotoxicity. However, the underlying mechanisms responsible for DOX-induced apoptosis have not been completely elucidated. In this study, we determine whether both ERK1/2/p53-dependent and NF-κB dependent-PUMA activation was related to DOX-induced apoptosis in H9c2 cells.

MATERIALS AND METHODS

H9c2 cells were treated with DOX (1 μM) for 2-48 hours. To explore the effect of ERK1/2, NF-KB, P53 and PUMA on DOX-induced apoptosis in H9c2 cells, H9c2 cells were transfected with PUMA siRNA or p65 siRNA, or treated with PFT-α (a chemical inhibitor of p53), or PD98059 (ERK inhibitor) before DOX treatment. MTT, Flow cytometry, TUNEL, Western blot and EMSA assay was used to detect cell survival, apoptosis, protein expression and NF-KB activity.

RESULTS

DOX induced apoptosis and inhibited growth of H9c2 cells in a time-dependent manner. DOX activated ERK1/2, NF-KB, p53 and PUMA. Knockdown of PUMA completely blocked DOX-induced cell apoptosis and survival inhibition. Knockdown of NF-KB or ERK1/2 alone could partly block DOX-induced PUMA upregulation and cell apoptosis. However, knockdown of NF-KB and ERK1/2 together completely blocked DOX-induced cell apoptosis and PUMA upregulation. In addition, knockdown of ERK1/2 blocked p53-dependent PUMA upregulation.

CONCLUSIONS

DOX induced apoptosis and inhibited growth of H9c2 cells by activation of ERK1/2/p53 and NF-κB dependent-PUMA signaling pathway.

Telomere-associated factor expression in replicative senescence of human embryonic lung fibroblasts

The objective of this study was to find the key regulatory molecules in the cell senescence process through observing the expression of telomere-associated factor during the normal cell replicative senescence process. Based on the established cell replicative senescence model, reverse transcription-polymerase chain reaction and western blot analyses were used to detect telomere-associated factor expression at the mRNA and protein levels, including that of human telomere binding protein 1, tankyrase 1, telomerase RNA, telomere protection protein 1 (POT1), and p53 during the process of human embryonic lung fibroblast replicative senescence. The results showed that transcription of human telomere binding protein 1 did not change with cell senescence, whereas the protein expression of human telomere binding protein 1 increased gradually and then decreased rapidly; there was no change in the mRNA and protein expression of POT1; with the replicative senescence of human embryonic lung fibroblasts, expression of POT1 decreased gradually; TRF1 showed an increasing trend with cell senescence; and p53 protein expression did not change. Together, the results from this study suggest that human telomere binding protein 1, POT1, and TRF1 played important roles in cell senescence.

First Report of Myrothecium roridum Causing Leaf Spot on Zantedeschia aethiopica in China

Zantedeschia aethiopica (L.) Spreng. (calla lily), belonging to family Araceae, is a popular ornamental plant in China. In the summer of 2010, leaves of calla lily with typical symptoms of necrotic lesions were observed in a commercial glasshouse in Beijing, China (116°20' E, 39°44' N). The initial symptoms were circular to subcircular, 1 to 3 mm, and dark brown lesions on the leaf lamina. Under high humidity, lesions expanded rapidly to 5 to 10 mm with distinct concentric zones and produced black sporodochia, especially on the backs of leaves. Later, the infected leaves were developing a combination of leaf lesions, yellowing, and falling off; as a result, the aesthetic value of the plant was significantly impacted. Leaf samples were used in pathogen isolation. Symptomatic leaf tissues were cut into small pieces and surface sterilized with 70% ethanol for 30 s and then in 0.1% mercuric chloride solution for 1 to 3 min. After being washed in sterile distilled water three times, the pieces were plated on potato dextrose agar (PDA) and incubated at 25°C in darkness for 7 days (5). Initial colonies of isolates were white, floccose mycelium and developed dark green to black concentric rings that were sporodochia bearing viscid spore masses after incubating 5 days. Conidiophores branched repeatedly. Conidiogenous cells were hyaline, clavate, and 10.0 to 16.0 × 1.4 to 2.0 μm. Conidia were hyaline, cylindrical, both rounded ends, and 6.0 to 8.2 × 1.9 to 2.4 μm. Morphological characteristics of the fungus were consistent with the description of Myrothecium roridum Tode ex Fr. (3,4). To confirm the pathogenicity, three healthy plants of calla lily were inoculated with a conidial suspension (1 × 10⁶ conidia per ml) brushed from a 7-day-old culture of the fungus. Control plants were sprayed with sterile water. The inoculated plants were individual with clear plastic bags and placed in a glass cabinet at 25°C. After 7 days, all inoculated leaves developed symptoms similar to the original samples, but control plants remained disease free. Re-isolation and identification confirmed Koch's postulates. For molecular identification, genomic DNA of a representative isolate (MTL07081001) was extracted by modified CTAB method (1), and the rDNA-ITS region was amplified by using primers ITS1 (5-TCCGTAGGTGAACCTGCGG-3) and ITS4 (5-TCCTCCGCTTATTGATATGC-3). The 465-bp amplicon (GenBank Accession No. KF761293) was 100% identity to the sequence of M. roridum (JF724158.1) from GenBank. M. roridum has an extensive host range, covering 294 host plants (2). To our knowledge, this is the first record of leaf spot caused by M. roridum on calla lily in China. References: (1) F. M. Ausubel et al. Current Protocols in Molecular Biology. John Wiley & Sons Inc, New York, 1994. (2) D. F. Farr and A. Y. Rossman, Fungal Databases. Syst. Mycol. Microbiol. Lab., ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , October 2013. (3) M. T. Mmbaga et al. Plant Dis. 94:1266, 2010. (4) Y. X. Zhang et al. Plant Dis. 95:1030, 2011. (5) L. Zhu et al. J. Phytopathol. 161:59, 2013.

First Report of Pseudomonas cichorii Causing Leaf Spot of Vegetable Sponge Gourd in China

A suspect bacterial leaf spot on vegetable sponge gourd (Luffa cylindrical (L.) Roem.) was found in a commercial greenhouse in Pi County, Chengdu City, Sichuan Province, China, in February 2011. Approximately 20 to 30% of plants were affected, causing serious economic loss. Symptoms occurred only on seedlings and consisted of water-soaked, irregularly shaped, black lesions on the surface and margins of cotyledons. A bacterium was consistently isolated on nutrient agar from diseased leaf tissues that had been surface disinfected in 70% ethyl alcohol for 30 s. The bacterium produced small gray colonies with smooth margins, was gram negative, fluoresced on King's B medium, and showed pectolytic activity when inoculated on potato slices. The partial sequences of 16SrRNA gene (1,377 bp) of the bacterium (GenBank Accession No. KC762217), amplified by using universal PCR primers 16SF (5'-AGAGTTTGATCCTGGCTCAG-3') and 16SR (5'-GGTTACCTTGTTACGACTT-3'), shared 100% similarity with that of Pseudomonas cichorii (GenBank Accession No. HM190228). The vegetable sponge gourd isolate was also identified by using the Biolog Microbial Identification System (version 4.2, Biolog Inc., Hayward, CA) as P. cichorii with the following characteristics (1): negative for arginine dihydrolase, gelatin liquefaction, and N₂ production. Positive reactions were obtained in tests for catalase, oxidase, potato rot, utilization of melibiose, and mannitol. Tests were negative for utilization of sucrose, trehalose, D-arabinose, raffinose, cellobiose, and rhamnose. A pathogenicity test was conducted on 4-week-old vegetable sponge gourd plants by spray-inoculation with 10⁸ CFU/ml sterile distilled water on the leaves of 15 vegetable sponge gourd plants and by needle puncture on the stems of 15 other plants with P. cichorii, respectively. Control plants were misted with sterile distilled water or punctured on the stem with a clean needle. Plants were placed in a greenhouse maintained at 28 ± 2°C with relative humidity of 80 to 85%. Symptoms, the same as seen on the original diseased plants, developed after 7 to 10 days on inoculated plants. Control plants remained healthy. The bacterium was readily re-isolated from inoculated plants and identified as P. cichorii using P. cichorii-specific primer hrpla/hrp2a (1). To our knowledge, this is the first report of P. cichorii causing disease on commercially grown vegetable sponge gourd in China. This new finding will provide the basis for developing resources for diagnostics and management, including screening varieties for resistance. References: (1) S. Mazurier et al. J. FEMS Microbiol. Ecol. 49:455, 2004. (2) N. W. Schaad et al., eds. Laboratory Guide for Identification of Plant Pathogenic Bacteria, 3rd ed. APS Press, St. Paul, MN, 2001.

Efficacy and tolerability of toremifene and tamoxifen therapy in premenopausal patients with operable breast cancer: a retrospective analysis

BACKGROUND

Given the use of tamoxifen as standard treatment for hormone receptor-positive breast cancer, the use of toremifene as an adjuvant endocrine therapy has not been widely examined. The present retrospective study compared the efficacy and safety of toremifene and tamoxifen in the treatment of operable hormone receptor-positive breast cancer in premenopausal women.

METHODS

Premenopausal patients with hormone receptor- positive operable breast cancer were eligible. Enrolled patients (n = 1847) received either 60 mg toremifene (n = 396) or 20 mg tamoxifen (n = 1451) daily for a minimum of 5 years after surgery. Disease-free survival (dfs) was the primary endpoint. Overall survival (os) and time to distant recurrence were secondary endpoints.

RESULTS

Treatment with toremifene and tamoxifen resulted in no between-group differences in dfs (p = 0.659) or os (p = 0.364). Mean dfs was 10.3 years for both groups. Mean os was 11.2 years for the toremifene group and 11.1 years for tamoxifen group. The 5-year dfs rate was 87.0% in the toremifene group and 85.0% in the tamoxifen group. The 5-year survival rate was 94.3% in the toremifene group and 93.5% in the tamoxifen group. Adverse events rates were similar in the two groups, with the exception of irregular menses, which occurred at a higher rate in the tamoxifen group than in the toremifene group (10.0% vs. 6.3%, p = 0.025).

CONCLUSIONS

In this retrospective study, the efficacy and safety profiles of toremifene and tamoxifen for the treatment of operable hormone receptor-positive breast cancer in premenopausal women were similar.

P16 and retinoblastoma protein expression in endometrial carcinoma and clinical significance

OBJECTIVE

To investigate the clinical significance of p16 expression, a product of the cyclin dependent kinase inhibitor CDKN2 (also known as MTS1, multiple tumor suppressor 1) and assess its relationship with retinoblastoma protein expression in the pathogenesis of endometrial cancer.

METHOD

p16 and pRb expression were histochemically evaluated, using p16 and RB polyclonal antibodies on paraffin sections of 27 primary endometrial adenocarcinomas with no therapy prior to surgery, through the streptavidin peroxydase conjugated method. Further analyses were carried out using the polymerase chain reaction for exon 1 gene amplification to investigate the mechanism of abnormal p16 expression.

RESULT

p16 expression was detected in 100% of normal endometriums and in 74.04% of endometrial carcinomas (p < 0.05). This was significantly associated with tumor cell grade (p < 0.05). PCR analysis of exon 1 in five cases with no detectable p16 expression revealed four homozygous deletions. Additionally, the inverse correlation between RB and p16 expression was confirmed in this study, with 71.42% of tumors demonstrating inverse expression of p16 and RB (p < .005).

CONCLUSION

p16 expression decrease is a significant event in endometrial carcinoma pathogenesis, and it is inversely correlated to tumor cell grade. Exon 1 homozygous deletion might be one of the mechanisms of loss of p16 expression. The p16/pRb growth suppressor pathway is targeted in human endometrial carcinoma.

First Report of Crown Rot of Grafted Cucumber Caused by Fusarium solani in China

Grafting has been widely and effectively used in cucumber (Cucumis sativus) cultivation for approximately 30 years in China to avoid Fusarium wilt caused by Fusarium oxysporum Schl. f. sp. cucumerinum Owen. In greenhouses, 90% of cucumbers are grafted onto pumpkin (Cucurbita moschata) rootstock. However, in March 2009, a severe crown rot causing yellowing and wilting of the leaves was observed on grafted cucumber in a large number of greenhouses in Lingyuan, western Liaoning Province in China. Symptoms consisted of dark brown, water-soaked lesions and a dense, white mycelial mat at the base of the stem. Lingyuan is the largest district for cucumber cultivation using grafting techniques in solar greenhouses in China. In 30 surveyed greenhouses in Sanshijiazi Village in the city of Lingyuan, the incidence of affected plants ranged from 10 to 40%, which caused serious economic losses. Fusarium spp. were isolated from the surface-sterilized basal stems of symptomatic plants on potato dextrose agar and incubated on potato sucrose agar for 4 days at 25°C. Colonies of the isolates produced a brown pigmentation and sparse, aerial mycelia, with a cream color on the underside. Conidiophores were elongated and branched or unbranched. Microconidia were abundant, hyaline, ellipsoid to ovoid, and 6 to 14 × 2.5 to 3.5 μm. Macroconidia were cylindrical, abundant, mostly two to six septate, 22 to 63 × 3.2 to 5.0 μm, with the apical cell rounded and blunt, and the basal cell rounded. On the basis of morphological characteristics, the fungus was identified as F. solani (C. Booth). For confirmation, the internal transcribed spacer region of rDNA was amplified and sequenced. A 449-bp sequence shared 99% homology with that of a F. solani GenBank accession previously reported from Japan (No. AF150473.1). The new sequence was deposited in GenBank (Accession No. HM015882). Pathogenicity of three isolates was determined in two experiments using different methods of inoculation. In one, 30 seedlings of pumpkin (C. moschata) with one true leaf each were inoculated by dipping their roots in a suspension of 10⁶ spores ml^-1, while control plants were mock inoculated with sterile water. Plants were then potted in a sterile mix of peat moss and vermiculite (2:1 vol/vol). In the other, pregerminated pumpkin seeds were sown in the same medium with a conidial suspension added at a rate of 10⁶ spores ml^-1, while other seeds were sown in sterile soil as controls. Plants for both experiments were maintained in a greenhouse at 25°C. Twelve days after inoculation, inoculated plants in both experiments showed a cortical rot on the crown and stem base with a brown, water-soaked appearance. Twenty-one days later, inoculated plants developed wilting and yellowed leaves. Disease incidence was 100%. No symptoms occurred on the control plants. Both experiments were repeated once with the same results. The pathogen was recovered from symptomatic tissue, confirming Koch's postulates. F. solani has been previously reported to cause root rot on cucurbit in California (2) and crown rot on grafted cucumber in the Netherlands (1). To our knowledge, this is the first report of crown rot of grafted cucumber caused by F. solani in China. References: (1) L. C. P. Kerling and L. Bravenboer. Neth. J. Plant Pathol. 73:15, 1967. (2) T. A. Tousson and W. C. Snyder. Phytopathology 51:17, 1961.

First Report of Myrothecium Leaf Spot of Common Bean in China Caused by Myrothecium roridum

Common bean (Phaseolus vulgaris L.) is an economically important crop in China. In June 2008, a new foliar disease was observed on beans in Shunyi District, Beijing, China. The disease occurred in approximately 15% of the plants in a commercial field. Leaf spots were circular to irregular, reddish brown, zonate, and 8 to 20 mm in diameter. Black sporodochia with white tuffs were present on older lesions and black spore masses were present in moist weather. Ten isolates recovered from lesions produced white, floccose colonies and spore masses after 4 days on potato dextrose agar. The rod-shaped, hyaline conidia had rounded ends and averaged 6.8 × 2.5 μm. All characteristics were consistent with the description of Myrothecium roridum Tode ex Fr. (1). The internal transcribed spacer regions of one isolate were sequenced and deposited in GenBank (Accession No. GQ 381291). Sequences of the isolate from bean in China were 98% similar to sequences of M. roridum in GenBank. To determine pathogenicity, 30 healthy seedlings of common bean were inoculated by spraying a 1 × 10⁵ conidia ml^-1 suspension of M. roridum onto the foliage. Ten seedlings were sprayed with sterile water and served as controls. Plants were kept in a humid chamber at 27°C overnight and then placed in a growth chamber. After 6 days, the symptoms described above were observed on leaves in all inoculated plants, whereas symptoms did not develop on the control plants. The pathogen was reisolated from inoculated leaves, fulfilling Koch's postulates. There is one report of M. roridum on soybean in Korea (2). To our knowledge, this is the first report of Myrothecium leaf spot on common bean in China. References: (1) M. Fitton et al. CMI Mycol. Pap. No. 253, 1970. (2) K. J. Yum et al. Plant Pathol. J. 6:313, 1990.

First Report of Target Leaf Spot Caused by Corynespora cassiicola on Balsam Pear in China

Balsam pear (Momordica charantia L.) is an economically important vegetable in China with increasing interest as a medicinal plant. In December of 2006, a new foliar disease caused by Corynespora cassiicola was observed on balsam pear growing in greenhouses in Shouguang City, Shandong Province, China. The disease occurred on 35% or less of the plants. Leaves of affected plants developed off-white halos surrounding circular lesions that were 1 to 5 mm broad. The lesions became dark brown, necrotic with concentric rings, and up to 15 mm in diameter. Severely affected plants eventually wilted and defoliated. Pieces of tissue from the leading edges of lesions were disinfected in 1% NaOCl for 1 min, rinsed in sterile water, and plated on potato dextrose agar. Colonies of the fungus were gray to dark green. Conidiophores were erect and simple, pale brown to brown, and 100 to 450 μm long and 3 to 8 μm wide. Conidia were obclavate to cylindrical, pale olivaceous brown to dark brown, smooth, 35 to 100 × 8 to 12 μm, and were produced in chains. On the basis of these characteristics, the fungus was identified as Corynespora cassiicola (1). The internal transcribed spacer (ITS) region of rDNA was amplified with primers ITS1/ITS4 and deposited in GenBank (Accession No. GQ381292). It was an exact match for a sequence of C. cassiicola previously deposited (Accession No. EU364555). To confirm pathogenicity, 30 1-month-old healthy seedlings of balsam pear were inoculated by spraying a suspension of conidia (1 × 10⁵ conidia per ml) of one isolate of C. cassiicola until runoff. Ten seedlings were sprayed with sterile water as controls. Plants were kept in a humidity chamber at 27°C overnight and then placed in a growth chamber at 27°C. After 7 days, symptoms identical to those described above were observed, while no symptoms developed on the control plants. The pathogen was reisolated from inoculated leaves. C. cassiicola causes foliar diseases on many plants, including tomato, eggplant, soybean, and cucumber (2). There is one report on balsam pear in Korea (3). To our knowledge, this is the first report of target leaf spot caused by C. cassiicola on balsam pear in China. References: (1) M. B. Ellis. CMI Mycol. Pap. No. 65, 1957. (2) M. B. Ellis et al. CMI Mycol. Pap. No. 303, 1971. (3) J. H. Kwon et al. Plant Pathol. J. 21:164, 2005.

The relevance of cell proliferation, vascular endothelial growth factor, and basic fibroblast growth factor production to angiogenesis and tumorigenicity in human glioma cell lines

Tumor growth is partially dependent on angiogenesis, a process that relies on angiogenic factors. Tumorigenicity of cancer cells is thought to be associated with the production of various angiogenic factors that stimulate or inhibit the rate of endothelial cell migration and proliferation. However, the relative importance of specific individual factors originally studied in cancer cell lines has yet to be determined in vivo. In this study, we examined seven human glioma cell lines for dynamic changes of two major angiogenic factors, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), and for doubling time and tumorigenicity in nude mice. Various correlation studies demonstrated that in these glioma cell lines, VEGF expression correlated well with RBC density in tumor sections (r2 = 0.804) and with average tumor weight (r2 = 0.987). In contrast, bFGF expression in the observed glioma cell lines did not correlate with tumorigenicity (r2 = 0.001) or with VEGF expression (r2 = 0.255). Furthermore, there was no correlation between doubling time and tumorigenicity in these cell lines (r2 = 0.160). Taken together, these results suggest that VEGF plays a major role in glioma formation and that down-regulation of VEGF, rather than bFGF, would be a more effective choice for glioma gene therapy.

[Expression of VEGF on rabbit skin fibroblasts using retroviral vector]

A replication-deficient recombinant retrovirus containing the cDNA coding for human vascular endothelial growth factor (VEGF) was generated, and then infected rabbit primary skin fibroblasts. After selection with G418, the transduced colonies have the ability of producing VEGF. The integration and expression of VEGF in transduced cells were confirmed by Southern blot, PCR, Northern blot and RT-PCR assay. The VEGF secreted by transduced cells has strong bioactivity when assayed by endothelial proliferation and Miles vascular permeability assay. Thus, this study pave the way for future study of biological and physiological effect of VEGF in vivo.

[Analysis of retinoic acid in subretinal fluid in patients with rhegmatogenous retinal detachment]

To investigate the relationship between the level of retinoic acid (RA) in the subretinal fluid (SRF) and the extent of the vitreoretinopathy in 56 patients with rhegmatogenous retinal detachment, we studied the levels of RA in both SRF and serum using high liquid chromatography and also examined those levels in part of patients who took oral vitamin A 150,000 U.d-1. The results were that the level of RA in the SRF increased with the grade of the proliferative vitreoretinopathy (PVR); the levels of RA in both SRF and serum were significantly higher in the cases with vitamin A than those without. We conclude that retinoic acid metabolism between retinal pigment epithelial cells and neural epithelia was unbalanced after retinal detachment. Oral vitamin A is helpful to inhibit the genesis and development of the proliferative vitreoretinopathy.

A mutant oncolytic adenovirus targeting the Rb pathway produces anti-glioma effect in vivo

Effective anti cancer strategies necessitate the use of agents that target tumor cells rather than normal tissues. In this study, we constructed a tumor-selective adenovirus, Delta24, that carries a 24-bp deletion in the E1A region responsible for binding Rb protein. Immunoprecipitation analyses verified that this deletion rendered Delta24 unable to bind the Rb protein. However, titration experiments in 293 cells demonstrated that the Delta24 adenovirus could replicate in and lyse cancer cells with great efficiency. Lysis of most human glioma cells was observed within 10 - 14 days after infection with Delta24 at 10 PFU/cell. In vivo, a single dose of the Delta24 virus induced a 66.3% inhibition (P<0.005) and multiple injections, an 83.8% inhibition (P<0.01) of tumor growth in nude mice. However, normal fibroblasts or cancer cells with restored Rb activity were resistant to the Delta24 adenovirus. These results suggest that the E1A-mutant Delta24 adenovirus may be clinically and therapeutically useful against gliomas and possibly other cancers with disrupted Rb pathway.

The breathing route dependence of ventilatory responses to hypercapnia and exercise is modulated by upper airway resistance

OBJECTIVE

The ventilatory response to hypercapnia is greater breathing orally than nasally.

METHODOLOGY

We hypothesize that this is due to higher nasal resistance to airflow compared with oral resistance. Seven normal male subjects were studied during both progressive hyperoxic hypercapnia (HC) and exercise (EX) until ventilation exceeded 40 L/min. Under each condition, subjects breathed via the nose only or the mouth only. For each breathing route, ventilation and pathway resistance were calculated simultaneously at the highest common exercise workload (140 +/- 20 watt; mean +/- SE) or the same end-tidal CO2 level (8.0 +/- 0.5%).

RESULTS

The ventilatory response breathing nasally was decreased by a similar amount for both EX and HC when compared with the oral route. The difference between nasal and oral ventilation was highly correlated with the difference between nasal resistance and oral resistance for both EX and HC (linear regression analysis; r = 0.91 for EX and r = 0.86 for HC; both P < 0.01).

CONCLUSION

We conclude that the breathing route dependence of ventilatory responses to respiratory stimuli in normal subjects is independent of the method of stimulation and is substantially determined by the added resistance of nasal breathing.

Alae nasi activation decreases nasal resistance during hyperoxic hypercapnia

It has been proposed that decreases in nasal resistance (Rn) during hypercapnia are entirely due to vasoconstriction in the nasal cavity. We hypothesized that alae nasi (AN) muscle activity dilates the nasal vestibule and contributes to the decrease in Rn during hypercapnia. Nine normal subjects were studied during hyperoxic hypercapnia (HH). Rn and vestibular resistance (Rvest) for one nasal passage were measured simultaneously with the AN electromyogram before and after nasal decongestion. HH decreased Rvest from 1.6 +/- 0.6 to 0.8 +/- 0.9 cmH2O . l-1 . s (predecongestant) and from 1.3 +/- 0.8 to 0.6 +/- 0.7 cmH2O . l-1 . s (postdecongestant; both P < 0. 01). Nasal decongestant decreased Rn but not Rvest. Significant inverse linear relationships between Rvest and AN electromyogram were demonstrated for all subjects. We conclude that in normal subjects during HH 1) decreases in Rvest are predominantly due to increases in AN activity; and 2) decreases in Rn are due to a combination of mucosal vasoconstriction and AN activation.

Hysteresis of the nasal pressure-flow relationship during hyperpnea in normal subjects

Hysteresis of the nasal airway pressure-flow relationship (PFR) is seen during hyperpnea, with lower nasal resistance during increasing inspiratory flow than during decreasing flow. We hypothesized that the nasal PFR hysteresis arose in the nasal vestibule airway because of progressive collapse during the inspiration. We measured the inspiratory transnasal and transvestibular PFR for one nasal passage in five normal subjects breathing via a nasal mask during voluntary hyperventilation, both with voluntary nostril flaring and without flaring. The inspiratory hysteresis (IH) was quantified as the ratio of the areas under the descending and ascending pressure-flow curves. Flaring reduced the vestibular IH from 1.96 +/- 0.06 to 1.15 +/- 0.06 and the nasal IH from 2.05 +/- 0.13 to 1.28 +/- 0.06 (both P < 0.01). Our results demonstrate that hysteresis arises in the compliant vestibule segment of the nasal airway, likely because of progressive collapse of the nasal vestibule during inspiration. The findings suggest that hysteresis is prevented by voluntary nostril flaring maintained throughout inspiration.

A novel approach to glioma gene therapy: down-regulation of the vascular endothelial growth factor in glioma cells using ribozymes

Glioblastoma multiforme is one of the most highly vascularized solid neoplasms, therefore treatments that target neovascularization process would be of great clinical importance. Studies of glioblastoma angiogenesis have revealed that expression of the vascular endothelial growth factor (VEGF) is up-regulated in these tumors. Previous reports have shown that down-regulation of VEGF correlates with modification in the glioma growth. To examine this phenomenon further, in this study we constructed two hammerhead ribozymes (RZI and RZII) to target the 5' common region of VEGF mRNA. Both ribozymes exhibited site-specific cleavage to a 318-nucleotide VEGF transcript and showed a high digestion efficiency in vitro (65-95%). After the transfection of glioma cells with two expression vectors carrying the ribozyme sequence, Northern blot analyses detected high levels of ribozyme expression. Treatment of the glioma cells with the ribozymes resulted in a reduction in VEGF mRNA in six of eight clones. Furthermore, the anti-VEGF effect was confirmed at protein level. Thus, enzyme-linked immunoabsorbent analyses (ELISA) showed a >70% reduction in the VEGF165 expression level. These results indicate that hammerhead ribozymes may be useful in down-regulating VEGF expression and suggest that anti-VEGF strategies may be used to potentiate other gene therapies targeting tumor suppressor genes.

Breathing route dependence of upper airway muscle activity during hyperpnea

Exercise (Ex) and hypercapnia (HC) both lead to increases in ventilation and upper airway muscle (UAM) activity. To determine whether different breathing routes (nasal vs. oral) or stimuli produced differential UAM activation, electromyographic (EMG) activity of the alae nasi (AN) and genioglossus (GG) were measured in seven normal subjects seated on a bicycle ergometer. Subjects performed paired runs during both progressive Ex and HC while breathing through the nose alone (N) or the mouth alone (O). During hyperpnea, AN EMG was greater when the subjects were breathing via N [81 +/- 6% maximum (HC) and 69 +/- 7% maximum (Ex)] than when they were breathing via O [30 +/- 5% maximum (HC) and 27 +/- 5% maximum (Ex); both P < 0.01], whereas the GG EMG did not differ between N and O. Both AN and GG EMG were similar for Ex and HC when the subjects were breathing via the same route. We conclude that UAM activation was independent of the nature of the stimulus. However, the AN muscle but not the GG muscle demonstrated breathing-route dependence of activity.

Evidence that cell surface beta 1,4-galactosyltransferase spontaneously galactosylates an underlying laminin substrate during fibroblast migration

beta 1,4-Galactosyltransferase is unusual among the glycosyltransferases in that a subpopulation exists on the cell surface in addition to its traditional biosynthetic location within the Golgi complex. On the cell surface, galactosyltransferase is expressed in spatially restricted, cell type-specific domains, where it functions as a receptor for extracellular oligosaccharide ligands during selected cellular interactions. For example, galactosyltransferase is found on the leading and trailing edges of migrating cells, where it facilitates lamellipodia formation and cell spreading by binding to specific N-linked oligosaccharides within laminin. Although the ability of galactosyltransferase to serve as a laminin receptor is well documented, it is unclear whether it functions solely in a lectin-like capacity to bind laminin glycoside ligands or uses its intrinsic catalytic activity to release itself from and modify its oligosaccharide substrate. In this study, we determined whether cell surface galactosyltransferase spontaneously galactosylates laminin matrices during cell migration using endogenous galactose donors. Cells were prelabeled with [3H]galactose, washed, and transferred in small clusters onto laminin matrices. The prelabeled cells migrated out from the cell cluster, during which time they deposited covalently bound [3H]galactose residues onto the laminin matrix. The degree of galactosylation was both laminin- and time-dependent and required actively migrating, intact cells. The radioactivity released from the 3H-galactosylated laminin by acid hydrolysis comigrated with authentic galactose standards on paper chromatography. In parallel assays, there was no radioactivity deposited on laminin matrices when cells were prelabeled with [3H]fucose or [3H]leucine. Furthermore, [3H]galactosylation was dependent upon galactosyltransferase-mediated cell migration, since prelabeled cells did not deposit [3H]galactose when migrating on fibronectin, upon which migration is integrin-dependent and galactosyltransferase-independent. These results raise the possibility that galactosyltransferase functions catalytically during cell migration, either to dissociate from its oligosaccharide ligand and/or to modify the extracellular matrix.

Vasovasostomy with use of medical needle as a support

Between May 1981 and December 1985 we performed vasovasostomy using a needle as a support in 43 patients who had undergone vasectomy for family planning. The operation is simple with little surgical trauma and few complications. All 39 patients who underwent semen analysis had return of spermatozoa. Pregnancy resulted in 27 of 34 patients (79.41 per cent) who attempted conception. The results were satisfactory. The procedure is described, and the complication and success rates are analyzed.

Isolation, purification & properties of lactose binding agglutination factor from rabbit skeletal muscle

The lactose binding agglutination factor from rabbit skeletal muscle is isolated through the use of lactose and urea. The factor is purified with DEAE cellulose and Sepharose 4B chromatography. The molecular weight of the factor is determined with Sephadex G-75 chromatography and found to be 28,000 Daltons. The subunit's molecular weight is determined by SDS gel electrophoresis, and found to be 14,000 Daltons. It was found that this binding factor can agglutinate trypsin-treated rabbit erythrocytes. Moreover, this agglutination is inhibited by EDTA and lactose.