Preoperative Abdominal Muscle Elongation Facilitated Laparoscopic Intraperitoneal Onlay Mesh Repair of Complex Ventral Hernia

Background: Complex ventral hernia remains a challenging situation for any surgeon. In this study, our aim was to analyze the effect of laparoscopic intraperitoneal onlay mesh (IPOM) repair in the treatment of complex abdominal wall hernia, with the assistance of preoperative progressive pneumoperitoneum (PPP) and botulinum toxin A (BTA). Methods: In this retrospective study, we included 13 patients with complex ventral hernia between May 2021 and December 2022. All patients undergoing PPP and BTA protocol before hernia repair. The length of abdominal wall muscles and abdominal circumference were measured from CT scan. All hernias were repaired with laparoscopic or laparoscopic-assisted IPOM. Results: Thirteen patients received PPP and BTA injections. PPP and BTA administration time was over 8.8 ± 2.5 days. Before and after PPP and BTA, imaging showed that the length of lateral muscle on each side increased from 14.3 to 17.4 cm (P < .05). The abdominal circumference increased from 81.8 to 87.9 cm (P < .05). Complete fascial closure was obtained in 13 patients (100%), and no patient experienced postoperative abdominal hypertension and ventilatory support. No patient suffered from recurrent hernia to date. Conclusions: Preoperative PPP combined with BTA injection plays a role similar to component separation technique, avoids the abdominal hypertension after laparoscopic IPOM repair of complex ventral hernia.

Concurrence of novel mutations causing Gilbert's and Dubin-Johnson syndrome with poor clinical outcomes in a Han Chinese family

Dual-hereditary jaundice (Dubin-Johnson syndrome (DJS) and Gilbert's syndrome (GS)) is a rare clinical entity resulting from defects of the ATP binding cassette subfamily C member 2 (ABCC2) and UDP glucuronosyltransferase family 1 member A1 (UGT1A1) genes with autosomal recessive inheritance. In this study, we aimed to investigate the mutation profiles and characterize the phenotypes in a Han Chinese family with DJS and GS. Genetic screening for variants in the ABCC2 and UGT1A1, immunohistochemistry for expression of ABCC2, and histopathological examination were carried out. The proband and his brother had unconjugated and conjugated hyperbilirubinemia after birth. The proband's sister had only conjugated hyperbilirubinemia after birth. The proband developed into pleural effusions and ascites, pericardial thickening, intrahepatic and extrahepatic biliary duct dilatation, and enlarged gallbladder at age 50. Hepatocellular carcinoma occurred in the proband's brother at age 46. Seven compound defects of the ABCC2 gene [c.2414delG, p.(Ile1489Gly), p.(Thr1490Pro), and p.(Ile1491Gln)] and the UGT1A1 gene (c.-3279T>G, p.(Gly71Arg), and p.(Pro451Leu)) were identified in family members. Accumulation of pigment in hepatocytes characteristic of that in DJS was present in the proband and his brother. Expression of ABCC2 protein was markedly diminished in the patient's liver. Our results show a different genetic profile of DJS and GS in a Han Chinese family, indicating a more complex pattern of dual-hereditary jaundice among different populations. The present study illuminates the underpinnings of DJS and GS and extends the mutation profiles and phenotypes of these two syndromes in dual-hereditary jaundice.

Application of a New Mesh Fixation Method in Laparoscopic Incisional Hernia Repair

Laparoscopic incisional hernia repair using intraperitoneal onlay mesh (IPOM) is one of the most widely used minimally invasive methods for repairing incisional hernias. The laparoscopic IPOM involves implanting the mesh into the abdominal cavity through laparoscopy to repair an abdominal wall hernia. In the IPOM surgery, after the closure of the hernia ring, an anti-adhesion mesh is placed laparoscopically. The correct placement of this mesh is critical to the success of the method, and surgical skills are required to achieve perfect placement. If the mesh placement is not mastered properly, the operation and anesthesia time will be prolonged. In addition, improper placement of the mesh can lead to serious consequences, such as intestinal obstruction and mesh infection. A "contraposition and alignment" mesh fixation method is described in this study, which involves pre-marking the fixation position of the mesh to reduce the difficulty of mesh placement. A properly placed mesh is completely flat on the peritoneum, the edges are not curled or wrapped, and the mesh is adhered firmly such that there is no displacement after removing the pneumoperitoneum pressure. The "contraposition and alignment" mesh fixation technique offers the advantages of reliable placement of the mesh and fewer complications than other techniques, and it is easy to learn and master. It also allows for positioning the nail gun in advance based on the anatomy of the incisional hernia. This enables the use of the minimum number of nails possible while still ensuring good fixation, which can reduce the occurrence of complications and reduce the cost of surgery. Thus, the mesh fixation method described here is highly suitable for clinical applications based on the aforementioned advantages.

Immunogenicity, durability, and safety of an mRNA and three platform-based COVID-19 vaccines as a third dose following two doses of CoronaVac in China: A randomised, double-blinded, placebo-controlled, phase 2 trial

BACKGROUND

More effective vaccine candidates against variants of concern as a booster dose are needed in people primed with two-dose inactivated COVID-19 vaccines.

METHODS

This randomised, double-blinded, investigator-initiated phase 2 trial aims to evaluate immunogenicity, durability, and safety of an mRNA vaccine candidate (RQ3013) and three other platform vaccines (an adenovirus-vectored vaccine candidate [ChAdTS-S], a recombinant protein vaccine candidate [ZR202-CoV], and an inactivated vaccine [CoronaVac]) as a booster. 250 eligible volunteers, who had received a prime two-dose CoronaVac (3 to 5 weeks apart) vaccination 100-270 days before, were randomly assigned in a 1:1:1:1:1 ratio to receive a third dose of RQ3013 (30 μg mRNA per 0.15 mL), ChAdTS-S (5×10¹⁰ viral particles per 0.5 mL), ZR202-CoV (25 μg prefusion-stabilized Spike ectodomain trimer per 0.5 mL), CoronaVac (3 μg inactivated CN02 strain of SARS-CoV-2 per 0.5 mL) or placebo (0.5 mL of 0.9% sodium chloride solution) via intramuscular injection into the upper arm at a single clinical site in Kunming, China. Participants, investigators, and immunogenicity laboratory were masked to group assignment. The primary immunogenicity outcomes were geometric mean titres (GMTs) of neutralising antibodies against live SARS-CoV-2 (wild-type, delta and omicron) virus at day 0 (before vaccination), day 7, day 14 and day 28 after vaccination, as analysed in a modified intention-to-treat (mITT) population (all participants who completed their booster doses and had at least one post-dose immunogenicity data). Secondary outcomes include T cell responses against the wild-type and omicron SARS-CoV-2 Spike protein. The primary safety outcome was incidence of adverse events within 14 days after the booster vaccination. This trial is registered with ChiCTR.org.cn, ChiCTR2200057758.

FINDINGS

Between January 1, 2022, and February 28, 2022, 235 eligible participants were enrolled and vaccinated, and the primary analysis included 234 participants. At baseline, neutralising antibodies against wild-type virus, the delta, or omicron variants were low or undetectable in all groups. After the booster vaccination, GMTs of neutralising antibodies ranged from 75.4 (95% confidence interval [CI] 61.4-92.5) in CoronaVac to 950.1 (95% CI 785.4-1149.3) in RQ3013 against live wild-type SARS-CoV-2, and from 8.1 (95% CI: 6.1-10.7) in CoronaVac to 247.0 (95% CI 194.1-314.3) in RQ3013 against the omicron variant at day 14. Immunogenicities of all heterologous regimens were superior to that of homologous regimen in neutralisation against all tested SARS-CoV-2 strains, with RQ3013 showing the highest geometric mean ratios (GMRs) of 12.6, 14.7, and 31.3 against the wild-type, the delta variant and the omicron variant compared to CoronaVac at day 14 post-vaccination, respectively. Durability analysis at day 90 showed that >90% of participants in RQ3013 and ZR202-CoV were seropositive for the omicron variant while ZR202-CoV with adjuvants containing CpG showed a slightly better durability than RQ3013. T cell responses specific to the omicron variant were similar to that of the wild-type, with RQ3013 showing the highest boosting effect. Any solicited injection site or systemic adverse events reported within 14 days after vaccination were most commonly observed in RQ3013 (47/47, 100%), followed by ZR202-CoV (46/47, 97.9%) and ChAdTS-S (43/48, 89.6%), and then CoronaVac (37/46, 80.4%) and placebo (21/47, 44.7%). More than 90% of the adverse events were grade 1 (mild) or 2 (moderate) with a typical resolution time of 3 days. No grade 4 adverse events or serious adverse events were reported by study vaccines.

INTERPRETATION

Although all study vaccines boosted neutralising antibodies with no safety concerns, RQ3013 showed much stronger cross-neutralisation and cellular responses, adding more effective vaccine candidates against the omicron variant.

FUNDING

Yunnan Provincial Science and Technology Department China (202102AA100051 and 202003AC100010), the Double First-class University funding to Yunnan University, National Natural Science Foundation of China (81960116, 82060368 and 82170711), Yunnan Natural Science Foundation (202001AT070085), High-level Health Technical Personnel Project of Yunnan Province (H-2018102) and Spring City Plan: The High-level Talent Promotion and Training Project of Kunming.

Risk factor analysis and clinical decision tree model construction for diabetic retinopathy in Western China

BACKGROUND

Diabetic retinopathy (DR) is the driving force of blindness in patients with type 2 diabetes mellitus (T2DM). DR has a high prevalence and lacks effective therapeutic strategies, underscoring the need for early prevention and treatment. Yunnan province, located in the southwest plateau of China, has a high pre-valence of DR and an underdeveloped economy.

AIM

To build a clinical prediction model that will enable early prevention and treatment of DR.

METHODS

In this cross-sectional study, 1654 Han population with T2DM were divided into groups without (n = 826) and with DR (n = 828) based on fundus photography. The DR group was further subdivided into non-proliferative DR (n = 403) and proliferative DR (n = 425) groups. A univariate analysis and logistic regression analysis were conducted and a clinical decision tree model was constructed.

RESULTS

Diabetes duration ≥ 10 years, female sex, standing- or supine systolic blood pressure (SBP) ≥ 140 mmHg, and cholesterol ≥ 6.22 mmol/L were risk factors for DR in logistic regression analysis (odds ratio = 2.118, 1.520, 1.417, 1.881, and 1.591, respectively). A greater severity of chronic kidney disease (CKD) or hemoglobin A 1c increased the risk of DR in patients with T2DM. In the decision tree model, diabetes duration was the primary risk factor affecting the occurrence of DR in patients with T2DM, followed by CKD stage, supine SBP, standing SBP, and body mass index (BMI). DR classification outcomes were obtained by evaluating standing SBP or BMI according to the CKD stage for diabetes duration < 10 years and by evaluating CKD stage according to the supine SBP for diabetes duration ≥ 10 years.

CONCLUSION

Based on the simple and intuitive decision tree model constructed in this study, DR classification outcomes were easily obtained by evaluating diabetes duration, CKD stage, supine or standing SBP, and BMI.

Cuproptosis-related long non-coding RNAs model that effectively predicts prognosis in hepatocellular carcinoma

BACKGROUND

Cuproptosis has recently been considered a novel form of programmed cell death. To date, long-chain non-coding RNAs (lncRNAs) crucial to the regulation of this process remain unelucidated.

AIM

To identify lncRNAs linked to cuproptosis in order to estimate patients' prognoses for hepatocellular carcinoma (HCC).

METHODS

Using RNA sequence data from The Cancer Genome Atlas Live Hepatocellular Carcinoma (TCGA-LIHC), a co-expression network of cuproptosis-related genes and lncRNAs was constructed. For HCC prognosis, we developed a cuproptosis-related lncRNA signature (CupRLSig) using univariate Cox, lasso, and multivariate Cox regression analyses. Kaplan-Meier analysis was used to compare overall survival among high- and low-risk groups stratified by median CupRLSig risk score. Furthermore, comparisons of functional annotation, immune infiltration, somatic mutation, tumor mutation burden (TMB), and pharmacologic options were made between high- and low-risk groups.

RESULTS

Three hundred and forty-three patients with complete follow-up data were recruited in the analysis. Pearson correlation analysis identified 157 cuproptosis-related lncRNAs related to 14 cuproptosis genes. Next, we divided the TCGA-LIHC sample into a training set and a validation set. In univariate Cox regression analysis, 27 LncRNAs with prognostic value were identified in the training set. After lasso regression, the multivariate Cox regression model determined the identified risk equation as follows: Risk score = (0.2659 × PICSAR expression) + (0.4374 × FOXD2-AS1 expression) + (-0.3467 × AP001065.1 expression). The CupRLSig high-risk group was associated with poor overall survival (hazard ratio = 1.162, 95%CI = 1.063-1.270; P < 0.001) after the patients were divided into two groups depending upon their median risk score. Model accuracy was further supported by receiver operating characteristic and principal component analysis as well as the validation set. The area under the curve of 0.741 was found to be a better predictor of HCC prognosis as compared to other clinicopathological variables. Mutation analysis revealed that high-risk combinations with high TMB carried worse prognoses (median survival of 30 mo vs 102 mo of low-risk combinations with low TMB group). The low-risk group had more activated natural killer cells (NK cells, P = 0.032 by Wilcoxon rank sum test) and fewer regulatory T cells (Tregs, P = 0.021) infiltration than the high-risk group. This finding could explain why the low-risk group has a better prognosis. Interestingly, when checkpoint gene expression (CD276, CTLA-4, and PDCD-1) and tumor immune dysfunction and rejection (TIDE) scores are considered, high-risk patients may respond better to immunotherapy. Finally, most drugs commonly used in preclinical and clinical systemic therapy for HCC, such as 5-fluorouracil, gemcitabine, paclitaxel, imatinib, sunitinib, rapamycin, and XL-184 (cabozantinib), were found to be more efficacious in the low-risk group; erlotinib, an exception, was more efficacious in the high-risk group.

CONCLUSION

The lncRNA signature, CupRLSig, constructed in this study is valuable in prognostic estimation of HCC. Importantly, CupRLSig also predicts the level of immune infiltration and potential efficacy of tumor immunotherapy.

Mitochondrial DNA haplogroup F confers genetic susceptibility to chronic HBV infection for the Yi nationality in Lijiang, China

Mitochondria are essential for hepatitis B virus (HBV) infection. Moreover, the findings of our previous study indicate that host mitochondrial genetic factors are associated with chronic hepatitis B (CHB) for the Han Chinese. However, in terms of genetic heterogeneity, the impact of mitochondria on host susceptibility to HBV infection in ethnic minorities in China remains unclear. Here, a total of 7070 subjects who had visited the hospital between June 1, 2019, and April 31, 2020, were enrolled for seroprevalence of HBV infection investigation. A total of 220 individuals with CHB (CHBs) and 223 individuals with a trace of HBV infection (spontaneously recovered subjects, SRs) were analyzed for mitochondrial DNA (mtDNA) sequence variations and classified into respective haplogroups. Haplogroup frequencies were compared between CHBs and SRs. Among eight nationalities, Yi nationality patients had the highest HBsAg prevalence rate (27.9% [95% CI: 25.3%-30.5%]) and the lowest vaccination rate (4.9% [95% CI: 3.7%-6.2%]). After adjustment for age and gender, haplogroup F was a risk factor for CHB infection (P = 0.049, OR = 2.079, 95% CI = 1.002-4.31), while D4 had a significant negative correlation with the HBeAg-positive rate (P = 0.024, OR = 0.215, 95% CI = 0.057-0.816). Together with our previous study, the findings indicate that different nationalities have different genetic susceptibility to HBV infection.

Botulinum Toxin A Facilitated Laparoscopic Repair of Complex Ventral Hernia

Background: Complex ventral hernia repair can be challenging despite the recent advances in surgical techniques. Here, we aimed to examine the effectiveness of preoperative combined use of botulinum toxin A (BTA) and preoperative progressive pneumoperitoneum (PPP) for surgical preparation of patients with complex ventral hernia.

Methods: In this prospective, observational study, we included 22 patients with complex ventral hernia between January 2018 and May 2021. All patients were treated with BTA injections into the lateral abdominal muscles and PPP before hernia repair. The lengths of abdominal wall muscles, the volumes of the incisional hernia (VIH), the volumes of the abdominal cavity (VAC), and the VIH/VAC ratio were measured before and after BTA and PPP using abdominal CT scan. All Hernias were repaired using laparoscopic intra-peritoneal onlay mesh (IPOM) or laparoscopic-open-laparoscopic (LOL) techniques.

Results: Imaging showed a significant increase in the mean lateral abdominal muscle length from 13.1 to 17.2 cm/side (p < 0.01). Before and after BTA and PPP, the mean VIH was 894 cc and 1209 cc (P < 0.01), and the mean VAC was 6,692 cc and 9,183 cc (P < 0.01). The VAC increased by 2,491 cc (P < 0.01) and was greater than the mean VIH before PPP. An average reduction of 0.9% of the VIH/VAC ratio after BTA and PPP was obtained (p > 0.05). All hernias were surgically reduced with mesh, hernia recurrence occurred in only two patients.

Conclusions: The preoperative combined use of PPP and BTA increased the abdominal volume, lengthened the laterally retracted abdominal muscles, and facilitated laparoscopic closure of large complex ventral hernia.

Application of Straight-needle, Three-tailed, Knot-free, Peritoneal Sutures in Laparoscopic Transabdominal Preperitoneal Hernia Repair

Laparoscopic transabdominal preperitoneal hernia repair (TAPP) is one of the most widely used methods in inguinal hernia surgery. After the mesh is placed, the peritoneum must be resutured to avoid contact with the tissues and organs in the abdominal cavity. If the peritoneal suture time is too long, the operation and anesthesia time will be prolonged, increasing the burden on the patient. Moreover, improper suture methods cause serious consequences, such as intestinal obstruction and mesh infection. The straight-needle suture method transforms the three-dimensional spatial configuration of the needle holder and the arc needle tip into a two-dimensional planar structure, which greatly reduces the difficulty of suturing. The three-tailed knot can be anchored at the beginning of the suture by its friction and button effect, which has an exact fixation effect. Thus, the suture does not easily slip, and the time to complete the suturing is shortened. Compared with the traditional suture method, the operator can suture the peritoneum more quickly, beginners can pass through the difficult learning curve faster, and skilled operators can also shorten the total operation time of TAPP to a certain extent. Thus, this suture method is extremely amenable to clinical application.

Predictors of lymph-node metastasis in surgically resected T1 colorectal cancer in Western populations

Background

The risk of lymph-node metastasis (LNM) in T1 colorectal cancer (CRC) has not been well documented in heterogeneous Western populations. This study investigated the predictors of LNM and the long-term outcomes of patients by analysing T1 CRC surgical specimens and patients’ demographic data.

Methods

Patients with surgically resected T1 CRC between 2004 and 2014 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Patients with multiple primary cancers, with neoadjuvant therapy, or without a confirmed histopathological diagnosis were excluded. Multivariate logistic-regression analysis was used to identify the predictors of LNM.

Results

Of the 22,319 patients, 10.6% had a positive lymph-node status based on the final pathology (nodal category: N1 9.6%, N2 1.0%). Younger age, female sex, Asian or African-American ethnicity, poor differentiation, and tumor site outside the rectum were significantly associated with LNM. Subgroup analyses for patients stratified by tumor site suggested that the rate of positive lymph-node status was the lowest in the rectum (hazard ratio: 0.74; 95% confidence interval: 0.63–0.86).

Conclusion

The risk of LNM was potentially lower in Caucasian patients than in API or African-American patients with surgically resected T1 CRC. Regarding the T1 CRC site, the rectum was associated with a lower risk of LNM.

Preoperative Progressive Pneumoperitoneum and Botulinum Toxin Type A in Patients With Large Parastomal Hernia

Background: The combination of preoperative progressive pneumoperitoneum (PPP) and botulinum toxin type A (BTA) in adjuvant treatment of large parastomal hernia (LPH) has not been reported in the previous literature.

Methods: From February 2018 to June 2019, 16 patients were diagnosed with LPH in our hospital were included in this study. All patients received PPP and BTA treatment to expand abdominal volume and extend abdominal muscle before surgery. The laparoscopic Sugarbaker method was preferred for defect close.

Results: Before and after PPP and BTA, the mean volume of the parastomal hernia (VPH) was 1,522 and 1,644 cc, respectively (P < 0.01), and the mean volume of the abdominal cavity (VAC) was 5,847 and 9,408 cc, respectively (P < 0.01). The VPH/VAC ratio was decreased by an average of 8.4% after the combination management. And the lateral abdominal muscle length was increased by an average of 4.8 cm/side (P < 0.01). These patients underwent surgery successfully, and no hernia recurrence after (17.6 ± 2.4) months of follow-up.

Conclusions: The combination of PPP and BTA effectively expand the abdominal volume, decrease the risk of abdominal compartment syndrome (ACS) postoperatively, and beneficial to laparoscopic repair of LPH.

Molecular Subtypes and CD4+ Memory T Cell-Based Signature Associated With Clinical Outcomes in Gastric Cancer

Background

CD4⁺ memory T cells are an important component of the tumor microenvironment (TME) and affect tumor occurrence and progression. Nevertheless, there has been no systematic analysis of the effect of CD4⁺ memory T cells in gastric cancer (GC).

Methods

Three datasets obtained from microarray and the corresponding clinical data of GC patients were retrieved and downloaded from the Gene Expression Omnibus (GEO) database. We uploaded the normalize gene expression data with standard annotation to the CIBERSORT web portal for evaluating the proportion of immune cells in the GC samples. The WGCNA was performed to identify the modules the CD4⁺ memory T cell related module (CD4⁺ MTRM) which was most significantly associated with CD4⁺ memory T cell. Univariate Cox analysis was used to screen prognostic CD4⁺ memory T cell-related genes (CD4⁺ MTRGs) in CD4⁺ MTRM. LASSO analysis and multivariate Cox analysis were then performed to construct a prognostic gene signature whose effect was evaluated by Kaplan-Meier curves and receiver operating characteristic (ROC), Harrell’s concordance index (C-index), and decision curve analyses (DCA). A prognostic nomogram was finally established based on the CD4⁺ MTRGs.

Result

We observed that a high abundance of CD4⁺ memory T cells was associated with better survival in GC patients. CD4⁺ MTRM was used to stratify GC patients into three clusters by unsupervised clustering analysis and ten CD4⁺ MTRGs were identified. Overall survival, five immune checkpoint genes and 17 types of immunocytes were observed to be significantly different among the three clusters. A ten-CD4⁺ MTRG signature was constructed to predict GC patient prognosis. The ten-CD4⁺ MTRG signature could divide GC patients into high- and low-risk groups with distinct OS rates. Multivariate Cox analysis suggested that the ten-CD4⁺ MTRG signature was an independent risk factor in GC. A nomogram incorporating this signature and clinical variables was established, and the C-index was 0.73 (95% CI: 0.697–0.763). Calibration curves and DCA presented high credibility for the OS nomogram.

Conclusion

We identified three molecule subtypes, ten CD4⁺ MTRGs, and generated a prognostic nomogram that reliably predicts OS in GC. These findings have implications for precise prognosis prediction and individualized targeted therapy.

Nine-long non-coding ribonucleic acid signature can improve the survival prediction of colorectal cancer

BACKGROUND

Investigating molecular biomarkers that accurately predict prognosis is of considerable clinical significance. Accumulating evidence suggests that long non-coding ribonucleic acids (lncRNAs) are frequently aberrantly expressed in colorectal cancer (CRC).

AIM

To elucidate the prognostic function of multiple lncRNAs serving as biomarkers in CRC.

METHODS

We performed lncRNA expression profiling using the lncRNA mining approach in large CRC cohorts from The Cancer Genome Atlas (TCGA) database. Receiver operating characteristic analysis was performed to identify the optimal cutoff point at which patients could be classified into the high-risk or low-risk groups. Based on the Cox coefficient of the individual lncRNAs, we identified a nine-lncRNA signature that was associated with the survival of CRC patients in the training set (n = 175). The prognostic value of this nine-lncRNA signature was validated in the testing set (n = 174) and TCGA set (n = 349). The prognostic models, consisting of these nine CRC-specific lncRNAs, performed well for risk stratification in the testing set and TCGA set. Time-dependent receiver operating characteristic analysis indicated that this predictive model had good performance.

RESULTS

Multivariate Cox regression and stratification analysis demonstrated that this nine-lncRNA signature was independent of other clinical features in predicting overall survival. Functional enrichment analysis of Kyoto Encyclopedia of Genes and Genomes pathways and Gene Ontology terms further indicated that these nine prognostic lncRNAs were closely associated with carcinogenesis-associated pathways and biological functions in CRC.

CONCLUSION

A nine-lncRNA expression signature was identified and validated that could improve the prognosis prediction of CRC, thereby providing potential prognostic biomarkers and efficient therapeutic targets for patients with CRC.

Ultrasensitive supersandwich-type electrochemical sensor for SARS-CoV-2 from the infected COVID-19 patients using a smartphone

The recent pandemic outbreak of COVID-19 caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a threat to public health globally. Thus, developing a rapid, accurate, and easy-to-implement diagnostic system for SARS-CoV-2 is crucial for controlling infection sources and monitoring illness progression. Here, we reported an ultrasensitive electrochemical detection technology using calixarene functionalized graphene oxide for targeting RNA of SARS-CoV-2. Based on a supersandwich-type recognition strategy, the technology was confirmed to practicably detect the RNA of SARS-CoV-2 without nucleic acid amplification and reverse-transcription by using a portable electrochemical smartphone. The biosensor showed high specificity and selectivity during in silico analysis and actual testing. A total of 88 RNA extracts from 25 SARS-CoV-2-confirmed patients and eight recovery patients were detected using the biosensor. The detectable ratios (85.5 % and 46.2 %) were higher than those obtained using RT-qPCR (56.5 % and 7.7 %). The limit of detection (LOD) of the clinical specimen was 200 copies/mL, which is the lowest LOD among the published RNA measurement of SARS-CoV-2 to date. Additionally, only two copies (10 μL) of SARS-CoV-2 were required for per assay. Therefore, we developed an ultrasensitive, accurate, and convenient assay for SARS-CoV-2 detection, providing a potential method for point-of-care testing.

The association of the heterogeneity of HBV reverse transcriptase quasispecies with antiviral efficacy after treatment with nucleos(t)ide analogues for 10 years

To assess the heterogeneity of HBV reverse transcriptase (RT) quasispecies during 10 years of antiviral therapy and their association with antiviral efficacy. Nineteen patients with chronic hepatitis B (CHB) infection receiving nucleos(t)ide analogues (NAs) were enrolled. Based on the antiviral efficacy after 1 year of treatment, 5 patients were grouped into an early virologic response (EVR) group, while 8 patients were grouped into a late virologic response (LVR) group. Furthermore, 6 CHB patients that had undergone antiviral treatment for 10 years were grouped into a virologic breakthrough (VBT) group. The HBV RT from each patient were amplified, cloned, and sequenced. The complexity of the RT gene in the EVR group was significantly higher than that in the LVR (P = 0.0393) and VBT groups (P = 0.0141). Phylogenetic tree analysis showed that the average branch length of the EVR and LVR groups were significantly greater than that of VBT group (P < 0.001). The complexity (at the nucleotide level) of the RT quasispecies was negatively correlated with the corresponding HBV DNA load (P = 0.0163) at one year post-antiviral treatment. Moreover, both the LVR and VBT groups accumulated more deleterious mutations than the EVR group. After 1 year of NAs treatment, the increased HBV quasispecies complexity and evolutionary topologies, coupled with less deleterious mutations, are likely associated with a favorable efficacy during long-term antiviral treatment.

Expression and prognostic value of Chromobox family members in gastric cancer

Background

The Chromobox (CBX) protein family, which is a crucial part of the epigenetic regulatory complex, plays an important role in the occurrence and development of cancer; however, the function and prognostic value of CBX family members in gastric cancer is not clear.

Methods

we investigated the relationship between CBX members and gastric cancer using a range of tools and databases: Oncomine, Kaplan-Meier plotter, cBioPortal, ULCAN, Metascape, and GEPIA.

Results

The results showed that, relative to normal gastric tissue, mRNA expression levels of CBX1-6 were significantly higher in gastric cancer tissue, whereas the level of CBX7 was significantly lower. Furthermore, overexpression of CBX3-6 and underexpression of CBX7 mRNAs was significantly related to the poor prognosis and survival of gastric cancer patients, making these CBX family members useful biomarkers. Finally, overexpression of CBX1 mRNA was significantly related to the poor prognosis of gastric cancer patients treated with adjuvant 5-fluorouracil-based chemotherapy.

Conclusions

The members of the CBX family can be used as prognosis and survival biomarkers for gastric cancer and CBX1 may be a biomarker for choosing the chemotherapy regimen of gastric cancer patients.

Impact of Site-Specific Metastases on Surgical Value and Survival among Metastatic Colorectal Cancer Patients

We aimed to explore the potential prognostic impact of the metastatic site on the management approach and prognosis of stage IV colorectal cancer patients with synchronous metastases. Synchronous metastatic colorectal cancer patients reported to the Surveillance, Epidemiology, and End Results Program database between 2010 and 2013 were included in this study. Overall survival (OS) was compared between patients with different treatment options using risk-adjusted Cox proportional hazard regression models. Overall, 17,776 patients with stage IV colorectal cancer were identified. Of these patients, 2,052 (11.5%) underwent surgical resection for tumors at both the primary and meta-static sites. Patients who underwent surgical resection of both primary and metastatic sites with liver, lung, and simultaneous liver and lung metastases had a longer median OS ( P < 0.001) than patients who underwent nonsurgical treatments. Cox regression analysis revealed that surgical resection of both primary and metastatic sites was associated with a significantly enhanced OS ( P < 0.001). Colorectal cancer patients with hepatic or pulmonary metastases, who underwent metastasectomy, even in selected patients with both hepatic and pulmonary metastases after multidisciplinary evaluation, could have a better survival benefit than patients who underwent nonsurgical treatments.

Impact of Site-Specific Metastases on Surgical Value and Survival among Metastatic Colorectal Cancer Patients

We aimed to explore the potential prognostic impact of the metastatic site on the management approach and prognosis of stage IV colorectal cancer patients with synchronous metastases. Synchronous metastatic colorectal cancer patients reported to the Surveillance, Epidemiology, and End Results Program database between 2010 and 2013 were included in this study. Overall survival (OS) was compared between patients with different treatment options using risk-adjusted Cox proportional hazard regression models. Overall, 17,776 patients with stage IV colorectal cancer were identified. Of these patients, 2,052 (11.5%) underwent surgical resection for tumors at both the primary and metastatic sites. Patients who underwent surgical resection of both primary and metastatic sites with liver, lung, and simultaneous liver and lung metastases had a longer median OS (P < 0.001) than patients who underwent nonsurgical treatments. Cox regression analysis revealed that surgical resection of both primary and metastatic sites was associated with a significantly enhanced OS (P < 0.001). Colorectal cancer patients with hepatic or pulmonary metastases, who underwent metastasectomy, even in selected patients with both hepatic and pulmonary metastases after multidisciplinary evaluation, could have a better survival benefit than patients who underwent nonsurgical treatments.

Polymorphisms in the Uncoupling Protein 2 Gene Are Associated with Diabetic Retinopathy in Han Chinese Patients with Type 2 Diabetes

BACKGROUND

The uncoupling protein 2 (UCP2) gene plays an important role in the complications of type 2 diabetes (T2D). However, the association between variants in the UCP2 gene and diabetic retinopathy (DR) in Han Chinese T2D patients remains unclear.

METHODS

Two single-nucleotide polymorphisms (SNPs) [rs659366 (-866G/A) and a 45-bp insertion/deletion (I/D) in the 3'-UTR] in the UCP2 gene were genotyped in a study cohort of 209 T2D patients with DR and 199 T2D patients without DR by direct DNA sequencing.

RESULTS

Logistic regression analysis showed that the AA and GA genotypes of rs659366 were significantly associated with an increased risk for nonproliferative DR (NPDR) in the codominant model (corrected p-value <0.01) and the dominant model (corrected p-value = 0.006). Patients harboring the II and DI genotypes had a higher risk for PDR in the codominant model (corrected p-value = 0.011) and the dominant model (corrected p-value = 0.006), and the DI genotype showed a higher risk for NPDR in the dominant model (corrected p-value = 0.007) or codominant model (corrected p-value = 0.006). Further, haplotype analyses verified that the A-I haplotype is a risk haplotype for NPDR and PDR.

CONCLUSION

This study suggests that the UCP2 gene may be involved in the pathogenesis of NPDR and PDR in Han Chinese patients with T2D.

Correlations between mitochondrial DNA haplogroup D5 and chronic hepatitis B virus infection in Yunnan, China

Mitochondrial abnormality is frequently reported in individuals with hepatitis B virus (HBV) infection, but the associated hosts’ mitochondrial genetic factors remain obscure. We hypothesized that mitochondria may affect host susceptibility to HBV infection. In this study, we aimed to detect the association between chronic HBV infection and mitochondrial DNA in Chinese from Yunnan, Southwest China. A total of 272 individuals with chronic HBV infection (CHB), 310 who had never been infected by HBV (healthy controls, HC) and 278 with a trace of HBV infection (spontaneously recovered, SR) were analysed for mtDNA sequence variations and classified into respective haplogroups. Haplogroup frequencies were compared between HBV infected patients, HCs and SRs. Haplogroup D5 presented a higher frequency in CHBs than in HCs (P = 0.017, OR = 2.87, 95% confidence interval [CI] = (1.21–6.81)) and SRs (P = 0.049, OR = 2.90, 95% CI = 1.01–8.35). The network of haplogroup D5 revealed a distinct distribution pattern between CHBs and non-CHBs. A trend of higher viral load among CHBs with haplogroup D5 was observed. Our results indicate the risk potential of mtDNA haplogroup D5 in chronic HBV infection in Yunnan, China.

Evolution of full-length genomes of HBV quasispecies in sera of patients with a coexistence of HBsAg and anti-HBs antibodies

Although the evolutionary changes of viral quasispecies are correlated to the pathological status of a disease, little is known in the coexistence of hepatitis B surface antigen (HBsAg) and antibodies to these antigens (anti-HBs). To examine evolutionary changes in hepatitis B virus (HBV) and their relationship to the coexistence of HBsAg and anti-HBs antibodies, HBV genomes in patients with a coexistence of HBsAg and anti-HBs antibodies (experimental group) and HBsAg positive without anti-HBs (control group) were assessed. Our results showed that quasispecies diversity was significantly higher in the experimental group for large HBsAg (LHBsAg), middle HBsAg (MHBsAg), and HBsAg genes. LHBsAg harbored dN/dS values eight times higher in the experimental group; however, the mean dN/dS ratios in genes HbxAg, Pol and PreC/C of the experimental patients had an opposite trend. Phylogenetic trees in the experimental group were more complex than the control group. More positive selection sites, mutations and deletions were observed in the experimental group in specific regions. Furthermore, several amino acid variants in epitopes were potentially associated with the immune evasion. In conclusion, cumulative evolutionary changes in HBV genome that facilitate immune evasion provide insights into the genetic mechanism of a coexistence of HBsAg and anti-HBs antibodies.

MicroRNA-520c enhances cell proliferation, migration, and invasion by suppressing IRF2 in gastric cancer

Dysregulation of microRNA (miRNA) is actively involved in the development and progression of gastric cancer (GC). MiR‐520c was previously found to be overexpressed in GC specimens and cells. However, the clinical significance of miR‐520c and its biological function in GC remain largely unknown. Here, we found that miR‐520c expression in GC tissues was significantly increased compared to normal adjacent gastric tissues. Its increased level was prominently correlated with poor clinical parameters and prognosis of GC patients. Accordingly, the expression of miR‐520c was obviously elevated in GC cell lines as compared with gastric epithelial cells. Overexpression of miR‐520c in N‐87 cells significantly increased the proliferative ability, migration, and invasion of cancer cells, while miR‐520c silencing suppressed MKN‐45 cell proliferation, migration, and invasion in vitro. Mechanically, miR‐520c inversely regulated interferon regulatory factor 2 (IRF2) abundance in GC cells. Herein, IRF2 was found to be a downstream target of miR‐520c in GC. Furthermore, IRF2 was down‐regulated in GC tissues compared to nontumor tissues. An inverse correlation between IRF2 and miR‐520c expression was observed in GC cases. Taken together, miR‐520c may serve as a prognostic predictor and a therapeutic target for GC patients.

Inhibition of Sonic Hedgehog Signaling Pathway by Thiazole Antibiotic Thiostrepton Attenuates the CD44+/CD24-Stem-Like Population and Sphere-Forming Capacity in Triple-Negative Breast Cancer

BACKGROUND/AIM

Triple-negative breast cancer (TNBC) represents a particular clinical challenge because these cancers do not respond to endocrine therapy or other available targeted agents. The lack of effective agents and obvious targets are major challenges in treating TNBC. In this study we explored the cytostatic effect of thiazole ring containing antibiotic drug thiostrepton on TNBC cell lines and investigated the molecular mechanism.

METHODS

Cell viability was measured by MTT assay. Cell surface marker was monitored by FCM. Western blot was applied to assess the protein expression levels of target genes.

RESULTS

We found that thiostrepton remarkably suppressed the CD44+/CD24- stem-like population and sphere forming capacity of TNBC cell lines. Notably, we showed for the first time that thiostrepton exerted its pharmacological action by targeting sonic hedgehog (SHH) signaling pathway. Thiostrepton repressed SHH ligand expression and reduced Gli-1 nuclear localization in TNBC cell line. Furthermore, the downstream target of SHH signaling undergone dose-dependent, rapid, and sustained loss of mRNA transcript level after thiostrepton treatment. Finally, we showed that SHH ligand was essential for maintaining CD44+/CD24- stem-like population in TNBC cell line.

CONCLUSION

We conclude that thiostrepton suppresses the CD44+/CD24- stem-like population through inhibition of SHH signaling pathway. Our results give a new insight into the mechanism of thiostrepton anti-tumor activity and suggest thiostrepton as a promising agent that targets hedgehog signaling pathway in TNBC.

Identification of HNF4A Mutation p.T130I and HNF1A Mutations p.I27L and p.S487N in a Han Chinese Family with Early-Onset Maternally Inherited Type 2 Diabetes

Maturity-onset diabetes of the young (MODY) is characterized by the onset of diabetes before the age of 25 years, positive family history, high genetic predisposition, monogenic mutations, and an autosomal dominant mode of inheritance. Here, we aimed to investigate the mutations and to characterize the phenotypes of a Han Chinese family with early-onset maternally inherited type 2 diabetes. Detailed clinical assessments and genetic screening for mutations in the HNF4α, GCK, HNF-1α, IPF-1, HNF1β, and NEUROD1 genes were carried out in this family. One HNF4A mutation (p.T130I) and two HNF1A polymorphisms (p.I27L and p.S487N) were identified. Mutation p.T130I was associated with both early-onset and late-onset diabetes and caused downregulated HNF4A expression, whereas HNF1A polymorphisms p.I27L and p.S487N were associated with the age of diagnosis of diabetes. We demonstrated that mutation p.T130I in HNF4A was pathogenic as were the predicted polymorphisms p.I27L and p.S487N in HNF1A by genetic and functional analysis. Our results show that mutations in HNF4A and HNF1A genes might account for this early-onset inherited type 2 diabetes.

Identification of PSEN1 mutations p.M233L and p.R352C in Han Chinese families with early-onset familial Alzheimer's disease

Early-onset familial Alzheimer's disease (EOFAD) is characterized by the onset of dementia symptoms before 65 years, positive family history, high genetic predisposition, and an autosomal dominant inheritance. We aimed to investigate mutations and to characterize phenotypes in Chinese EOFAD families. Detailed clinical assessments and genetic screening for mutations in the presenilin 1 (PSEN1), presenilin 2, amyloid precursor protein, and APOE genes were carried out in 4 EOFAD families. Two PSEN1 mutations (p.R352C and p.M233L) were identified in 2 EOFAD families, respectively. Mutation p.M233L was associated with prominent very early onset, rapidly progressive dementia, and neurologic symptoms, whereas p.R352C was associated with a progressive dementia, psychiatric syndrome, and chronic disease course. Both mutations are predicted to be pathogenic. Our results showed that mutations in PSEN1 gene might be common in Chinese EOFAD families.

Complete mitochondrial genome of the Indian peafowl (Pavo cristatus), with phylogenetic analysis in phasianidae

Pavo cristatus, known as the Indian peafowl, is endemic to India and Sri Lanka and has been domesticated for its ornamental and food value. However, its phylogenetic status is still debated. Here, to clarify the phylogenetic status of P. cristatus within Phasianidae, we analyzed its mitochondrial genome (mtDNA). The complete mitochondrial DNA (mtDNA) genome was determined using 34 pairs of primers. Our data show that the mtDNA genome of P. cristatus is 16,686 bp in length. Molecular phylogenetic analyses of P. cristatus was performed along with 22 complete mtDNA genomes belonging to other species in Phasianidae using Bayesian and maximum likelihood methods, where Aythya americana and Anas platyrhynchos were used as outgroups. Our results show that P. critatus has its closest genetic affinity with Pavo muticus and belongs to clade that contains Gallus, Bambusicola and Francolinus.

Adaptive evolution of the Hox gene family for development in bats and dolphins

Bats and cetaceans (i.e., whales, dolphins, porpoises) are two kinds of mammals with unique locomotive styles and occupy novel niches. Bats are the only mammals capable of sustained flight in the sky, while cetaceans have returned to the aquatic environment and are specialized for swimming. Associated with these novel adaptations to their environment, various development changes have occurred to their body plans and associated structures. Given the importance of Hox genes in many aspects of embryonic development, we conducted an analysis of the coding regions of all Hox gene family members from bats (represented by Pteropus vampyrus, Pteropus alecto, Myotis lucifugus and Myotis davidii) and cetaceans (represented by Tursiops truncatus) for adaptive evolution using the available draft genome sequences. Differences in the selective pressures acting on many Hox genes in bats and cetaceans were found compared to other mammals. Positive selection, however, was not found to act on any of the Hox genes in the common ancestor of bats and only upon Hoxb9 in cetaceans. PCR amplification data from additional bat and cetacean species, and application of the branch-site test 2, showed that the Hoxb2 gene within bats had significant evidence of positive selection. Thus, our study, with genomic and newly sequenced Hox genes, identifies two candidate Hox genes that may be closely linked with developmental changes in bats and cetaceans, such as those associated with the pancreatic, neuronal, thymus shape and forelimb. In addition, the difference in our results from the genome-wide scan and newly sequenced data reveals that great care must be taken in interpreting results from draft genome data from a limited number of species, and deep genetic sampling of a particular clade is a powerful tool for generating complementary data to address this limitation.

Genome-wide scan for bats and dolphin to detect their genetic basis for new locomotive styles

For most mammals, running is their major locomotive style, however, cetaceans and bats are two mammalian groups that have independently developed new locomotive styles (swimming and flying) from their terrestrial ancestors. In this study, we used a genome-wide comparative analysis in an attempt to identify the selective imprint of the development of new locomotive styles by cetaceans and bats to adapt to their new ecological niches. We found that an elevated proportion of mitochondrion-associated genes show evidence of adaptive evolution in cetaceans and on the common ancestral lineage leading to bats, compared to other terrestrial mammals. This result is consistent with the fact that during the independent developments of swimming and flying in these two groups, the changes of energy metabolism ratios would be among the most important factors to overcome elevated energy demands. Furthermore, genes that show evidence of sequence convergence or parallel evolution in these two lineages were overrepresented in the categories of energy metabolism, muscle contraction, heart, and glucose metabolism, genes that perform functions which are essential for locomotion. In conclusion, our analyses showed that on the dolphin and bat lineages, genes associated with locomotion not only both show a greater propensity to adaptively evolve, but also show evidence of sequence convergence, which likely reflects a response to a common requirement during their development of these two drastic locomotive styles.

[Expression and regulation of milk protein gene in mammalia]

On the basis of introducing the structures and relations of evolution in milk protein genes, the factors involved in gene expression including cis-acting elements, trans-acting factors as well as induction of hormones were discussed. Finally the applicable prospect of mammary gland as a bioreactor was estimated.

[On the central inhibition action of tetrahydroberberine without relevance to GABA receptors]

Using an earthworm (Eisenia foetida) dorsal muscle preparation, it was shown that tetrahydroberberine (THB, 10(-7)-10(-4) mol/L) did not affect both GABA and ACh receptors. DA receptor antagonist haloperidol (HAL) also exerted no effect. Owing to the blocking action of isonicotinyl hydrazine (INH) and thiosemicarbazide (TSC) on biosynthesis of GABA, and of picrotoxin (PT) and bicuculline (Bic) on the GABA-BZ receptor complex mediated transmission, all these agents could induce convulsion in mice. This action could be antagonized by amino- oxyacetic acid (AOAA) and benzodiazepine (BZ), but not by DA receptor antagonists THB and HAL. All the above observations indicate that the GABA inhibition is not involved in the central action of THB.

[Effects of epidermal growth factor on growth and differentiation of rat granulosa cells]

It was known that epidermal growth factor (EGF) plays an important role in the regulation of reproduction. The present study was undertaken to investigate the effect of EGF on the proliferation and differentiation of cultured rat granulosa cells. The results showed that EGF inhibited the 3H-TdR incorporation into DNA of granulosa cells, while the progesterone production was increased due to enhanced 3 beta-HSD activity. Radioreceptor assay (RRA) suggested that there were specific receptors for EGF on the granulosa cell with a Kd of 1.83 +/- 0.30 x 10(-8) mol/L and a Bmax of 1.75 +/- 0.29 x 10(4) sites/cell. Using method of immunohistochemistry, no EGF-like immunoreactivity was found in the granulosa cells at different age or different estrous cycle, but in the theca folliculi, interstitium and corpus luteum. These results suggest that EGF can regulate the growth and differentiation of the granulosa cells in the course of maturation of the folliculi and granulosa cells.

Effects of monoclonal antibody anti-EGF receptor on human nasopharyngeal carcinoma cell and other tumor cells

Three anti-EGF receptor MoAbs were used in these studies. Administration of MoAbs 3 and 176 inhibited tumor formation in nude mice by CNE-2, a poorly differentiated nasopharyngeal carcinoma cell line and A431, an epidermoid carcinoma cell line. When the same MoAbs were used in treatment against HeLa, a cervical carcinoma, tumor growth was not affected. The number of EGF receptors and apparent dissociation constants for 125I-EGF on CNE-2 and A431 was 1.3 x 10(5)/cell (Kd 7.7 x 10(-8) mol/L) and 1.4 x 10(6)/cell (Kd 2.4 x 10(-9) mol/L), respectively. Both MoAbs 3 and 176, capable of competing with EGF for receptor binding, showed significant tumor growth inhibition. MoAb 101 was incapable of blocking the binding of EGF to its receptor, and not as effective as MoAbs 3 and 176 in tumor growth inhibition. Our observation is that the MoAb anti-EGF receptor is cytostatic rather than cytocidal, in vitro against CNE-2 and A431.

Growth inhibition of human nasopharyngeal carcinoma in athymic mice by anti-epidermal growth factor receptor monoclonal antibodies

Monoclonal antibodies (MoAbs) were developed against epidermal growth factor (EGF) receptor on the human epidermoid carcinoma cell line A431. The A431 antigen recognized by the MoAbs has an apparent molecular weight of approximately 170,000, with the same molecular weight as the CNE-2 cell line (poorly differentiated nasopharyngeal carcinoma). Administration of anti-EGF receptor MoAbs inhibited tumor formation, caused by the CNE-2 and A431 cell lines, in athymic mice. When the same MoAbs were used in therapy against Tca8113 (a human tongue carcinoma) and HeLa cells (a human cervical carcinoma), tumor growth was not affected. The number of EGF receptors and the apparent dissociation constants for 125I-EGF on CNE-2 and A431 were 1.3 x 10(5)/cell (Kd 7.7 x 10(-8) M) and 1.4 x 10(6)/cell (Kd 2.4 x 10(-9) M), respectively. Three anti-EGF receptor MoAbs were used in these studies. MoAbs 3 and 176, capable of competing with EGF for receptor binding, showed significant tumor growth inhibition. MoAb 101 was incapable of blocking the binding of EGF to its receptor and was not as effective as MoAbs 3 and 176 in tumor growth inhibition. Our observation is that in vitro, MoAb anti-EGF receptor is cytostatic, rather than cytocidal, against CNE-2 and A431.

Benzodiazepine receptors in isolated adrenal glomerulosa cells

In our experiments the isolated rat adrenal glomerulosa cells displayed peripheral-type benzodiazepine receptors, which could bind to [3H] PK11195 with an apparent equilibrium dissociation constant (KD) of 9.4 +/- 2.8 nmol/L and a maximal binding capacity (Bmax) of 5.6 +/- 1.8 pmol/10(6) cells. The effects of five ligands: PK11195, Ro5-4846, flunitrazepam, diazepam and clonazepam on aldosterone secretion responses of isolated glomerulosa cells to angiotensin II or extracellular potassium ions were observed. The logarithm of EO50 for these ligands as stimulators was well correlated with the logarithm of their Ki value for [3H] PK11195 binding, suggesting that the stimulative effects might be mediated by the benzodiazepine receptor in isolated glomerulosa cells.

[Effects of an endogenous GABA receptor binding inhibitor on rat blood pressure]

The GABA receptor agonists GABA (400 micrograms icv) and muscimol (1 microgram icv) induced hypotension in urethane-anesthetized rats, while the GABA receptor antagonist bicuculline (2 micrograms icv) elicited hypertension. An endogenous GABA receptor binding inhibitor (1 mg), prepared from bovine cerebellum, showed bicuculline-like hypertensive action in a dose-dependent manner. It was antagonized by icv muscimol, but not by the alpha 2-adrenoceptor agonist clonidine. These in vivo results agree quite well with our previous in vitro receptor binding assay experiments.