[A clinical cohort study of split and whole liver transplantations]

Objective: To investigate the surgical efficacy of split liver transplantation. Methods: Patients who underwent liver transplantation at the Affiliated Hospital of Qingdao University between January 2015 and December 2022 were retrospectively analyzed. They were divided into split liver transplantation group (n=60) and whole liver transplantation group (n=765)according to graft types.In the split liver transplantation group, there were 23 males and 37 females, aged (52.5±10.2) years, and the body mass index was (22.4±3.3) kg/m2. In the whole liver transplantation group, there were 630 males and 135 females, aged (51.2±9.6) years, and body mass index was (24.5±3.7) kg/m2.The basic data of the two groups were matched 1∶1 using the propensity score matching method. The independent sample t test and χ2 test were used to compare the intraoperative and postoperative recovery of the two groups of donors and recipients. The overall survival rate and the graft survival rate of the two groups were analyzed by Kaplan-Meier method and the cumulative survival rate was compared by the Log-rank test. Results: Fifty-one well-matched pairs of data with similar baseline characteristics were obtained. The ratio of graft mass to recipient body weight in the matched split liver transplantation group was (1.78±0.55)%. Operation time(M(IQR))(10.8(1.5)hours vs. 8.0(1.9)hours,U=6.608,P<0.01) and cold ischaemia time(5.4(1.3)hours vs. 4.6(2.2)hours,U=2.825,P=0.005) were significantly longer in the split liver transplantation group than those in the whole liver transplantation group. Intra-operative anhepatic phase(53.0(15.0)minutes vs. 57.0(24.0)minutes,U=1.048,P=0.295),bleeding volume(1 000(1 400)ml vs. 1 200(1 200)ml,U=0.966,P=0.334) and intraoperative instillation of red blood cells(9.0(6.5)U vs. 11.0(11.0)U,U=1.732,P=0.083) were not significantly different between the two groups. However,the split liver transplantation group showed significantly longer postoperative intensive care unit stay(5.0(3.0)days vs. 4.0(4.0)days,U=2.677,P=0.007) and postoperative hospital stay(30.0(15.0)days vs. 26.0(15.0)days,U=2.237,P=0.025) and significantly higher incidence of postoperative complications(56.8%(29/51) vs. 36.6%(19/51),χ2=3.935,P=0.047) than the whole liver transplantation group. Furthermore,levels of alanine transaminase and aspartate aminotransferase were significantly higher on postoperative days 1,4 and 7 in the split liver transplantation group(all P<0.05) than in the whole liver transplantation group;however,there were no significant differences in these levels on postoperative days 14 and 28. The time to restoration of normal liver function in both groups(12.5(13.7)days vs. 9.0(12.5)days,U=1.607,P=0.108) was not statistically significant. Furthermore,the median follow-up time after surgery was 25.6 months in both groups. In postoperative years 1,2,3 and 5, the graft survival rates were 88.1%,80.8%,77.8% and 66.7% in the whole liver transplantation group and 80.3%,70.3%,67.3% and 60.5% in the split liver transplantation group(P=0.171),respectively. The patient survival rates in post-operative years 1,2,3 and 5 were 88.1%,80.8%,77.8% and 66.7% in the whole liver transplantation group and 80.3%,75.9%,70.3% and 63.3% in the split liver transplantation group,respectively(P=0.252). However,the differences of graft survival rates and patient survival rates between the two groups were not significant. Conclusion: Although it affects the early recovery of patients after liver transplantation,split liver transplantation has no effect on long-term survival rates and demonstrates surgical efficacy similar to that of whole liver transplantation.

[The efficacy of thin struct bare stents for the treatment of spontaneous isolated dissection of the superior mesenteric artery]

Objective: To examine the safety and effectiveness of thin struct bare stents for the treatment of spontaneous isolated dissection of the superior mesenteric artery (SIDSMA). Methods: The data of 32 patients admitted to First Hospital of Jiaxing (20 cases) and Jinling Hospital (12 cases) with SIDSMA from January 2016 to January 2021 were retrospectively analyzed. There were 27 males and 5 females, aging (54.8±9.4) years (range: 36 to 75 years). All patients were treated with thin struct bare stents. Controllable spring coils were used to fulfill the false lumen in 2 cases. Symptoms, vascular remodeling pattern at the SIDSMA lesion, and patency of the stents were observed during follow-up. Results: The surgical success rate was 100%. According to the length of the lesions and stents, the number of stents implanted was 1 in 17 cases, 2 in 11 cases and 3 in 4 cases. The angiography showed that blood flow in the stent was smooth and that the false lumen disappeared or weakened. The numerical rating scale for abdominal pain decreased from 6.1±1.5 (range: 4 to 10) preoperatively to 1.0 (1.0) (range: 0 to 3) 1 hour postoperatively (W=528, P<0.01). The compression rate of the true lumen of the superior mesenteric artery decreased from (92.3±6.7)% (range: 25% to 94%) preoperatively to 0.8 (1.2)% (range: 0 to 3.2%) 1 month postoperatively (W=528, P<0.01). The primary patency rate of CT angiography at 1 month postoperatively was 100%. The vascular remodeling rate was (92.3±6.7)% (range: 80% to 100%). All patients were followed for (46.3±17.0) months (range: 24 to 76 months). The cumulative patency rates in 1, 2 and 5 years were all 100%. Conclusion: The use of thin struct bare stents for SIDSMA is safety and efficacy.

Long non-coding RNA UCA1 mediates proliferation and metastasis of laryngeal squamous cell carcinoma cells via regulating miR-185-5p/HOXA13 axis

OBJECTIVE

LncRNA urothelial cancer associated 1 (UCA1) is involved in the development of laryngeal squamous cell carcinoma (LSCC), however, its specific mechanism is not fully clear.

PATIENTS AND METHODS

Quantitative reverse transcription-PCR (RT-qPCR) was conducted to determine the expressions of lncRNA-UCA1, miR-185-5p and homeobox A13 (HOXA13) in LSCC tissues and cell lines. Cell Counting Kit-8 assay, colony formation assay, wound healing assay, Transwell and flow cytometry, DIANA-LncBase V2, as well as Starbase, Targetscan, and Dual-Luciferase reporter gene system were conducted to detect and confirm the crosstalk networks among lncRNA-UCA1, miR-185-5p, and HOXA13.

RESULTS

The levels of UCA1 and HOXA13 were significantly higher and the expression of miR-185-5p was reduced in LSCC tissues and cell lines. Moreover, miR-185-5p was predicted as a target gene for lncRNA UCA1, while HOXA13 was the target gene for miR-185-5p. UCA1 siRNA inhibited the proliferation and invasion of LSCC cells, moreover, the proliferation and invasion of LSCC cells were suppressed by miR-185-5p mimics but were enhanced by miR-185-5p inhibitor. UCA1 siRNA and overexpressed HOXA13 reversed the promotive effects of miR-185-5p inhibitor and inhibitory effects of miR-185-5p mimics on cell proliferation and metastasis, respectively.

CONCLUSIONS

The current findings reveal the important role of lncRNA UCA1/miR-185-5p/HOXA13 regulatory network in LSCC cells, and potentially provide new insights into the pathogenesis of LSCC.

[Clinical characteristics and pregnancy outcomes of non-criteria obstetric antiphospholipid syndrome]

Objective: To study clinical characteristics and pregnancy outcomes under anti-coagulation therapy of non-criteria obstetric antiphospholipid syndrome. Methods: Patients suspected of obstetric antiphospholipid syndrome(OAPS) were recruited through Chinese Rheumatism Data Center from 2015 to 2019 consecutively. Patients fulfilling 2006 Sydney revised antiphospholipid syndrome criteria were classified as OAPS. Patients fulfilling definition of non-criteria OAPS(NCOAPS) by expert consensus on diagnosis and management of obstetric antiphospholipid syndrome of China were classified as NCOAPS. Clinical characteristics and laboratory results of two groups were compared. Live birth rates and pregnancy outcomes under anti-coagulation therapy were studied. Results: A total of 88 patients were enrolled, including 56 patients (63.6%) as OAPS, 32(36.4%) as NCOAPS. Live births were only reached in 16.1% (9/56) in OAPS patients and 12.5%(4/32) in NCOAPS. Fetal losses after 10 weeks of gestation and pre-eclampsia before 34 weeks were more common in OAPS group compared to NCOAPS group [78.6%(44/56) vs. 18.8%(6/32), P<0.001; 25.0%(14/56) vs. 3.1%(1/32), P=0.020, respectively]. After enrollment, 15 pregnancies were recorded in OAPS, 10 in NCOAPS, all of whom were treated with low-dose aspirin (LDA) combined with low-molecular weight heparin (LMWH). Live birth rates saw dramatic improvements compared to baseline levels in OAPS [16.1% (9/56) vs. 11/15] along with NCOAPS [12.5% (4/32) vs. 7/10]. Conclusion: Though NCOAPS and OAPS patients differ in antiphospholipid antibody spectrum and pattern of pregnancy morbidities, both groups benefit from LDA combined with LWMH treatment, as live birth rates improve. Non-criteria OAPS patients are recommended to receive anti-coagulation therapy during pregnancy.

Protective effects of sodium ferulate on flap transplantation via anti-inflammatory modulation and oxidative stress inhibition

Ischemia-reperfusion injury (IRI) has brought attention to flap failure in reconstructive surgery. To improve the prognosis of skin transplantation, we performed experimental IRI by surgical obstruction of blood flow and used sodium ferulate (SF) to prevent IRI in rats. After SF treatment, the morphological and histological changes of the skin flaps were observed by H&E and Masson's trichrome staining. We also detected the expression levels of COX-1, HO-1, and Ki67 by immunohistochemical and western blot analysis. Moreover, enzyme-linked immunosorbent assay was used to identify the content of tumor necrosis factor (TNF)-α, myeloperoxidase (MPO), malondialdehyde (MDA), and nitric oxide (NO) in peripheral blood and skin tissue. Compared with the model group, SF treatment significantly improved the recovered flap area (%) and promoted collagen synthesis. Cyclooxygenase-2 (COX-2) expression was significantly inhibited by heme oxygenase-1 (HO-1) induction after SF treatment. Furthermore, SF significantly inhibited the levels of TNF-α in peripheral blood, MPO and MDA in the skin tissue, and the increased synthesis of NO. Our results showed the protective effects of SF on IRI after flap transplantation and we believe that the protective effects of SF was closely related to the alleviation of the inflammatory response and the inhibition of the oxidative stress injury.

Large-scale screening and characterisation of Lemna aequinoctialis and Spirodela polyrhiza strains for starch production

Duckweed is considered a promising feedstock for bioethanol production due to its high biomass and starch production. Selection of duckweed strains with high starch accumulation is essential for application of duckweeds to bioethanol production. Geographic differentiation had a large influence on genetic diversity of duckweeds. Biomass production, starch content and starch amount in geographically isolated strains of 20 Lemna aequinoctialis and Spirodela polyrhiza were calculated to evaluate their potential for bioethanol production. The influence of different collection time, culture medium and NaCl concentration on starch accumulation of the best strains were analysed. The results showed that biomass production, starch content and starch production of duckweeds demonstrated clonal dependency. The best strain was L. aequinoctialis 6000, with biomass production of 15.38 ± 1.47 g m^-2 , starch content of 28.68 ± 1.10% and starch production of 4.39 ± 0.25 g m^-2 . Furthermore, starch content of L. aequinoctialis 6000 was highest after 8 h of light, tap water was the best medium for starch induction, and NaCl did not induce starch accumulation. This study suggests duckweed biomass production and starch production demonstrate clonal dependency, indicating that extensive clonal comparisons will be required to identify the most suitable isolates for duckweed selective breeding for bioethanol.

[The 460th case: lower extremity edema, positive fecal occult blood]

An 61-year-old woman presenting deep vein thrombosis and persistent positive anticardiolipin antibodies was diagnosed as antiphospholipid syndrome and treated with low molecular weight heparin. Before and after anticoagulant therapy, continuous positive fecal occult-blood was found asymptomatically. Colonoscopy confirmed rectal cancer. Antiphospholipid autoantibodies are non-specially positive in some malignances, especially in elder onset patients. Thus, routine screening of malignancies is strongly suggested.

[The clinical manifestations and thrombotic risk factors in primary antiphospholipid syndrome]

OBJECTIVE

To investigate the clinical characteristics in patients with primary antiphospholipid syndrome (PAPS) and to identify potential predictors of thrombotic events.

METHODS

A total of 107 patients with PAPS were enrolled in our study, who were admitted in Peking Union Medical College Hospital from January 2004 to December 2014. Demographic data, age at onset, disease duration, past history of hypertension and regular cigarette smoking, clinical manifestations, imaging characteristics, management and prognosis were retrospectively collected. Bivariate statistical analysis and logistical regression test were performed to compare the discrepancy between patients with or without thromboembolic events.

RESULTS

In 107 patients, there were 65 female and 42 male patients, with mean age (39.8±15.8) years old, median disease duration 10.5 (2.0, 48.0) months. A total of 72(67.3%) patients reported episodes of thromboembolic events, including 72 venous thromboses and 29 arterial thromboses. The most frequent venous thromboses were deep vein thromboses (35.5%), pulmonary embolism the second common (29.9%), with cranial venous sinus thromboses the following (8.4%). In arterial thromboembolic events, the incidence of transient ischemic attack (TIA) and ischemic stoke was the highest(14.0%), embolism of lower extremities the second (6.5%), and 4 patients (3.7%) with acute myocardial infarction. Sixty seven patients(62.6%)had positive lupus anticoagulant, 60 patients(56.1%)with positive anticardiolipin antibody, 32 patients(29.9%, 32/74) with positive β2 glycoprotein Ⅰ(β2GPⅠ). Forty patients(37.4%)had double positive antibodies, while 19 cases(17.8%)with triple positive. In logistical regression, aging (per 10 years) and hypocomplementemia were significantly related to venous thrombosis (OR=1.421, 95%CI 1.066-1.894, P<0.05, and OR=6.435, 95%CI 1.374-30.130, P<0.05, respectively). Cigarette smoking and triple positive antibodies were independent risk factors of arterial thrombosis (OR=3.996, 95%CI 1.079-14.795, P<0.05 and OR=3.166, 95%CI 1.102-9.097, P<0.05, respectively).

CONCLUSION

APS is an autoimmune disorder characterized by recurrent arterial and venous thromboembolic events. Venous thromboembolism is more common than the arterial. Age and hypocomplementemia are predictors of venous thromboembolism; while smoking and triple positive antibodies are independent risk factors of arterial thromboembolism.

[Intertumoral heterogeneity of molecular phenotype and analysis of prognosis in multifocal and multicentric breast cancer]

Objective: This study was designed to investigate the prognostic implications of the intertumoral heterogeneity of molecular phenotype in multifocal and multicentric breast cancer (MMBC). Methods: The clinical and follow-up data of 146 patients with MMBC from Jan.2009 to Dec. 2009 treated in Tumor Hospital Affiliated to Zhengzhou University were retrospectively analyzed. We used Kaplan-Meier curves to compare the survivals of patients who had tumors with molecular phenotypic heterogeneity and patients who had multifocal homogeneous tumors in molecular phenotype, and the survivals of patients who had heterogeneous tumor type and grade and who had homogeneous tumor type and grade.The corresponding hazard ratio was calculated by Cox proportional-hazards regression. Results: Intertumoral heterogeneity in histological type and grade of multiple breast cancer was detected in 16 of 146 patients (11.0%) and in 10 of 146 patients (6.8%), respectively. Interfocal heterogeneous molecular phenotype of multiple breast cancer was detected in 24 of 146 patients (16.4%). There was no significant difference in 5-year disease-free survival in multifocal cancer patients who had heterogeneous histological type and grade and who had homogeneous type and grade tumors (75.0% vs. 77.3%, P=0.808). Multifocal cancers patients who had heterogeneous tumorsin molecular phenotype compared with those with homogeneous tumors in molecular phenotype had worse 5-year disease-specific survival (78.7% vs. 58.3%, P=0.037), and had a greater risk of recurrence (HR=2.130, 95%CI=1.027-4.420; P=0.042). Phenotyping the additional cancer foci influenced the therapeutic decision in up to 16 patients(11.0%). Conclusions: Multifocal breast cancer patients who had heterogeneous tumors in molecular phenotype have a statistically significantly shorter disease-free survival. Phenotyping the additional cancer foci and managing with proper therapeutic decision may reduce the risk of recurrence or metastasis, and improve the outcomes of the patients.

Agrobacterium-mediated transformation of tomato (Solanum lycopersicum L.) using the expansin 10 (CsEXP10) gene

The cucumber expansin 10 (CsEXP10) gene was previously cloned from young cucumber fruits but its role has not been defined. To determine the role of this gene in plant growth and development, a CsEXP10 gene transformation system was established. The open reading frame of the gene was inserted behind the CaMV35S promoter of vector pCAMBIA1301, and the construct was introduced into tomato plants by Agrobacterium-mediated transformation. In total, 19 kanamycin-positive lines were produced and nine independent transgenic lines were identified by β-glucuronidase and polymerase chain reaction (PCR) analysis. Quantitative real-time PCR analysis showed that levels of the CsEXP10 transcript were higher in transgenic lines than in a non-transgenic line.

Natural variation of rice blast resistance gene Pi-d2

Studying natural variation in rice resistance genes of cultivated and wild rice relatives can predict resistance stability to rice blast fungus. In the present study, the protein coding regions of the rice R gene Pi-d2 in 35 rice accessions, including Oryza sativa L. subsp. indica Kato (Aus), indica (IND), temperate japonica (TEJ), tropical japonica (TRJ), aromatic (ARO); subgroups of Oryza sativa; 6 accessions of wild rice varieties; O. nivara; and O. rufipogon were analyzed. A total of 13 nucleotide differences were found in the open reading frames (ORFs) of Pi-d2. Translation of these ORFs revealed 9 variants; 3 were novel Pi-d2 variants. Variants H2 and H5 were identified in accessions of cultivated rice and O. nivara, H1, H3, H4, H6, and H8 were only identified in cultivated rice. H2 and H5 were the common types of IND and O. nivara, H8 was the common type of TRJ and AUS, H6 was the specific type of AUS, and H3 was the specific type of ARO. H7 and H9 were specific haplotypes of O. nivara and O. rufipogon, respectively. These findings demonstrate that Pi-d2 variants are useful indicators for each subgroup, and Pi-d2 is an ancient gene that predates speciation of rice subgroups.

The risk of bacteria in foam sclerotherapy: does the condition of the air in outpatient vs. operating rooms make a difference?

BACKGROUND

Foam sclerotherapy has been one of the most frequently applied therapeutic methods for the treatment of varicose veins and venous malformation. Few studies have investigated the sterile condition of the air used for foam creation.

OBJECTIVES

To evaluate the bacterial conditions in foam created from the air in outpatient and operating rooms used for sclerotherapy treatment, in order to provide the basis for clinical applications in foam sclerotherapy.

MATERIALS AND METHODS

In this study, we measured the amount of airborne microorganisms in the air in the operating room, and in the outpatient room, the polidocanol (POL) foam created using the air in the respective rooms, and the microorganisms present in the liquid POL. We used the settle plate method for air sampling. We used the Tessari method to generate foam. The experiment was repeated three times.

RESULTS

Typical bacterial colonies were formed on nutrient agar plates in both the outpatient room and operating room air groups. No colonies were cultivated in the liquid POL. Although the use of sterile or nonsterile air in sclerotherapy produces significantly different results in the counts of colony-forming units, there was no difference in the foam created using sterile or nonsterile air (i.e. no colonies were cultivated on either foam).

CONCLUSIONS

There is no increased risk of infection when using foam sclerotherapy in outpatient rooms compared with using foam created under sterile operating-room conditions.

Dynamic QTL analysis for fruit lycopene content and total soluble solid content in a Solanum lycopersicum x S. pimpinellifolium cross

Fruit lycopene content and total soluble solid content are important factors determining fruit quality of tomatoes; however, the dynamic quantitative trait loci (QTL) controlling lycopene and soluble solid content have not been well studied. We mapped the chromosomal regions controlling these traits in different periods in F(2:3) families derived from a cross between the domestic and wild tomato species Solanum lycopersicum and S. pimpinellifolium. Fifteen QTLs for lycopene and soluble solid content and other related traits analyzed at three different fruit ripening stages were detected with a composite interval mapping method. These QTLs explained 7-33% of the individual phenotypic variation. QTLs detected in the color-changing period were different from those detected in the other two periods. On chromosome 1, the soluble solid content QTL was located in the same region during the color-changing and full-ripe periods. On chromosome 4, the same QTL for lycopene content was found during the color-changing and full-ripe periods. The QTL for lycopene content on chromosome 4 co-located with the QTL for soluble solid content during the full-ripe period. Co-location of lycopene content QTL and soluble solid content QTLs may be due to pleiotropic effects of a single gene or a cluster of genes via physiological relationships among traits. On chromosome 9, the same two QTLs for lycopene content at two different fruit ripening periods may reflect genes controlling lycopene content that are always expressed in tomato fruit development.

Leafy head formation of the progenies of transgenic plants of Chinese cabbage with exogenous auxin genes

The experiment was performed to evaluate the progenies of plant lines transgenic for auxin synthesis genes derived from Ri T-DNA. Four lines of the transgenic plants were self-crossed and the foreign auxin genes in plants of T5 generation were confirmed by Southern hybridization. Two lines, D1232 and D1653, showed earlier folding of expanding leaves than untransformed line and therefore had early initiation of leafy head. Leaf cuttings derived from plant of transgenic line D1653 produced more adventitious roots than the control whereas the cuttings from folding leaves had much more roots than rosette leaves at folding stage, and the cuttings from head leaves had more roots than rosette leaves at heading stage. It is demonstrated that early folding of transgenic leaf may be caused by the relatively higher concentration of auxin. These plant lines with auxin transgenes can be used for the study of hormonal regulation in differentiation and development of plant organs and for the breeding of new variety with rapid growth trait.

Effect of virginiamycin on ruminal fermentation in cattle during adaptation to a high concentrate diet and during an induced acidosis

The objective of Exp. 1 was to compare the effects of virginiamycin (VM; 0, 175, or 250 mg x animal(-1) x d(-1)) and monensin/tylosin (MT; 250/ 90 mg x animal(-1) x d(-1)) on ruminal fermentation products and microbial populations in cattle during adaptation to an all-concentrate diet. Four ruminally cannulated, Holstein steers were used in a 4x4 Williams square design with 21-d periods. Steers were stepped up to an all-concentrate diet fed at 2.5% of BW once daily. Ruminal pH, protozoal counts, and NH3-N and VFA concentrations generally were unaffected by VM or MT. Mean counts of Lactobacillus and Streptococcus bovis were lower (P<.05) for VM-treated compared with control or MT-treated steers. Both VM and MT prevented the increase in Fusobacterium necrophorum counts associated with increasing intake of the high-concentrate diet observed in the control. The objective of Exp. 2 was to compare the effects of VM and MT on ruminal pH, L(+) lactate and VFA concentrations, and F. necrophorum numbers during carbohydrate overload. Six ruminally cannulated Holstein steers were assigned randomly to either the control, VM (175 mg/d), or MT (250 + 90 mg/d) treatments. Acidosis was induced with intraruminal administration of a slurry of ground corn and corn starch. The VM and MT premixes were added directly to the slurry before administration. Carbohydrate challenge induced acute ruminal acidosis (pH was 4.36 and L (+) lactate was 19.4 mM) in controls by 36 h. Compared with the controls, steers receiving VM or MT had higher (P<.05) ruminal pH, and the VM group had a lower (P<.05) L (+) lactate concentration. Fusobacterium necrophorum numbers initially increased in VM- and MT-administered steers. In the control steers, F. necrophorum was undetectable by 36 h. Virginiamycin seemed to control the growth of ruminal lactic acid-producing bacteria and, therefore, has the potential to moderate ruminal fermentation in situations that could lead to rapid production of lactic acid.

Prevalence of histoplasmin sensitivity in healthy adults and tuberculosis patients in southwest China

Two hundred and seventy-one healthy students and workers and 28 hospitalized tuberculosis patients living in Sichuan Province (southwest People's Republic of China; PRC) were tested with histolyn and tuberculin. The age of the tested subjects ranged from 17 to 22 years among the students, 17 to 38, among the workers and 17 to their 70s among the patients. Thirty-eight students (24%), 21 workers (18%) and 8 patients (29%) reacted positively to histolyn, none of the differences being statistically significant. Positive reactions were significantly more frequent among students from the south of Sichuan Province (35%) than from the north (6%). The rates of positive reaction to tuberculin in the students (25%) and in the workers (27%) indicates that tuberculous infection continues to be a significant problem in southwestern PRC. The significant rate of histolyn reaction among the tuberculosis patients raises the possibility of either infection with both Histoplasma capsulatum and Mycobacterium tuberculosis, or a missed diagnosis of chronic pulmonary histoplasmosis.

Ability of some K+ channel blockers to reverse inhibition of electrically evoked contractions of longitudinal muscle-myenteric plexus

Blockers selective for different potassium (K+) channels were examined for their ability to reverse inhibition of electrically evoked contractions of longitudinal muscle-myenteric plexus (lm-mp) by adenosine analogs. Cyclohexyl adenosine (CHA) was selected for these studies, since it effectively inhibited contraction (EC50 33 nM). 4-aminopyridine (4-AP) antagonized the inhibition by the adenosine analog, but also stimulated contraction by itself. alpha- and gamma-dendrotoxin produced the most profound reversal of CHA-induced inhibition, while producing a minimal contraction alone. Other blockers produced only nominal reversal of the CHA-induced inhibition. These results suggest that inhibition by CHA is mediated via activation of an alpha- and gamma-dendrotoxin-sensitive K+ channel.

Effects of calcitonin gene-related peptide on cyclic AMP production and relaxation of longitudinal muscle of guinea pig ileum

The effects of rat calcitonin gene-related peptide (rCGRP) on the content of cyclic nucleotides in the cells of plexus-free longitudinal muscle (LM) of guinea pig ileum relative to smooth muscle relaxation were investigated. In the absence of isobutyl-methyl-xanthine (IBMX), a nonspecific inhibitor of phosphodiesterases, rCGRP significantly increased cyclic 3'5'-adenosine monophosphate (cAMP) content that correlated temporally to the relaxation of the muscle. Cyclic 3'5'-guanosine monophosphate (cGMP) content was not affected by this peptide. IBMX potentiated both the increase in cAMP content and the muscle relaxation induced by rCGRP. rCGRP increased cAMP content in a concentration-dependent manner, with an ED50 value of 7.5 x 10(-9) M. Both the rCGRP-stimulated increase in cAMP content and the rCGRP-induced muscle relaxation were blocked by hCGRP(8-37), a selective antagonist of CGRP receptors. The pA2 value of hCGRP(8-37) for rCGRP-induced inhibition of tension was calculated to be 6.48. These results suggest that CGRP relaxes the LM through its specific receptors and involves the generation of cAMP, but not the generation of cGMP.

Effects of calcitonin gene-related peptide on intracellular calcium concentration in longitudinal muscle of guinea pig ileum

The effect of rat calcitonin gene-related peptide (rCGRP) on intracellular free calcium concentration ([Ca2+]i) and its relationship with muscle relaxation were examined in plexus-free longitudinal muscle (LM) of the guinea pig ileum using a [Ca2+]i-tension simultaneous recording technique. Tissue was stimulated with either histamine (0.5 microM) or KCl (30 mM). rCGRP at a concentration of 263 nM (which displayed maximal relaxation of the LM) caused a small and brief but significant decrease in the [Ca2+]i in histamine-treated tissue. On the other hand, the same concentration of rCGRP relaxed the muscle without affecting the [Ca2+]i in KCl-treated tissue. rCGRP caused a dissociation between the changes in [Ca2+]i and tension. The effects of forskolin 0.5 microM) and nifedipine (10 nM) on both [Ca2+]i and tension were examined in comparison with rCGRP. Forskolin lowered the tension to greater extent than the [Ca2+]i whereas nifedipine (10 nM) diminished both the [Ca2+]i and tension in a parallel manner in histamine-treated tissues. These results suggest that rCGRP may not reduce [Ca2+]i as its primary mechanism of relaxation and it may change the calcium sensitivity of the contractile elements of the smooth muscle.

K+ channel openers relax longitudinal muscle of guinea pig ileum

The plexus-free longitudinal muscle was used to investigate the muscle-relaxing effects of the known K+ channel openers, cromakalim, pinacidil and nicorandil, and compared with other known muscle relaxants, calcitonin gene-related peptide (CGRP) and isoprenaline. The three K+ channel openers all decreased basal tension and inhibited the tonic tension evoked by 30 mM KCl, 0.5 microM histamine or 0.1 microM oxotremorine in a dose-dependent manner. The order of potency is cromakalim > pinacidil > nicorandil in KCl or oxotremorine-precontracted muscle strip and nicorandil > cromakalim > pinacidil in histamine-precontracted muscle strip. Inhibition by cromakalim was completely reversed by glibenclamide, a blocker of ATP-sensitive K+ channels, while inhibition by nicorandil or pinacidil was only partially antagonized. The tonic tension evoked by KCl, histamine or oxotremorine was relaxed by CGRP or isoprenaline. Inhibition by neither of these compounds was relieved by glibenclamide. These results suggest that while ATP-sensitive K+ channels may be present in the longitudinal muscle cells, they may not be involved in the actions of CGRP or isoprenaline on the longitudinal muscle.

A study of primary- and re-infection with hepatitis C virus in blood transfusion recipients

A nested polymerase chain reaction was used to assess viraemia in blood transfusion recipients with no serological evidence of hepatitis C virus (HCV) infection (naive recipients) and in recipients with prior or existing HCV infection (infected recipients), who were transfused with HCV-positive blood. In 10 hepatitis cases in naive recipients, defined as primary infection, nine showed clinical hepatitis, and one was sub-clinical; the time between transfusion and elevation of alanine aminotransferase (ALT) levels was 15-60 days (37.9 +/- 13.9). All 10 naive recipients showed abnormal ALT, and 10/10 and 7/10 were persistently positive for anti-HCV and HCV-RNA, respectively, for more than 1 year. Similarly, in five cases in previously infected recipients, defined as re-infection, 4/5 showed clinical hepatitis, the time to elevation of ALT was 30-46 days (34.8 +/- 6.4), and 5/5 and 3/5 were persistently positive for anti-HCV and HCV-RNA, respectively, for more than 1 year. All five infected recipients showed abnormal ALT. In conclusion, there was no significant difference (P = 0.05) in the frequency of the markers of infection resulting from primary or re-infection with HCV, suggesting that primary infection fails to induce a protective immune response.

A dynamic study of viraemia in chronic hepatitis C infection

The dynamics of alanine aminotransferase (ALT), anti-hepatitis C virus and hepatitis C virus (HCV) RNA in six cases with chronic HCV infection were studied for 3-7 years. Two of the six cases showed continued elevation of ALT, and three showed intermittent elevation. All cases were persistently positive for anti-HCV after initial seroconversion. Five of the six cases were persistently positive for HCV RNA detected by nested polymerase chain reaction, and one was positive intermittently. Thus hepatitis C virus replicates continually in a majority of patients with chronic hepatitis C, although some cases may show intermittent replication, and replication of hepatitis C virus does not always correlate with elevated ALT.

Effects of calcitonin gene-related peptide on longitudinal muscle and myenteric plexus of guinea pig ileum

Effects of rat calcitonin gene-related peptide (rCGRP) on the longitudinal muscle-myenteric plexus (lm-mp) have been investigated in the present study. rCGRP was shown to have a biphasic effect on the nonstimulated lm-mp, i.e., a transient contraction followed by a longer lasting relaxation. This biphasic action was dose-dependent over the concentration range of 10(-10) to 10(-5) M. Tetrodotoxin (1 microM), atropine (1 microM), 2-chloroadenosine (1 microM) and clonidine (1 microM) inhibited the stimulatory effect. Tetrodotoxin and clonidine also partially inhibited the relaxing effect of rCGRP. This biphasic action of rCGRP was also seen on the contraction of the lm-mp elicited by electrical field stimulation. rCGRP showed only a relaxing effect on the nonstimulated plexus-free longitudinal muscle. rCGRP (2.6 x 10(-10) to 2.6 x 10(-7) M) inhibited both the phasic and tonic contractions induced by histamine in a competitive way and showed a more potent effect on the tonic contraction than that on the phasic contraction. rCGRP at the same dose range also inhibited the tonic but not phasic contraction evoked by membrane depolarization with the maximal stimulation of KCl (30 mM). rCGRP inhibited KCl-, but not histamine-induced, extracellular calcium-dependent contraction. The peptide did not affect the dose-response curve of oxotremorine. These results suggest that rCGRP may exert its stimulatory actions on the lm-mp via actions on the plexus nerves, whereas the depressant actions may be mediated via the nerves, as well as directly on the smooth muscle.

Epidemiologic investigation on an outbreak of hepatitis C

An outbreak of hepatitis in plasma donors occurred in a village of Hebei Province in the period of September to October 1985. The morbidity rate was 40.0% (26/65) in the plasma donors, which was significantly higher than that in whole blood donors (1/88) and in persons who were not blood donors (1/400). One to one paired survey was carried out, and the incidence was 46.4% (26/56) in the plasma donors, while there were no such outbreak in the control group. The distribution of cases showed positive correlation with the number of plasma donors from the production brigade. No secondary infection was found in their families. The peak of outbreak was about 2 months later than the peak of plasma donation. 26 cases of hepatitis in plasma donors all showed negative results for anti-HAV IgM, HBsAg, anti-HBC IgM, anti-CMV IgM and anti-EBV IgM. Sera of 25 cases were selected and sent to CDC, USA to confirm with Chiron C100 reagent. 24 cases were anti-HCV positive. This outbreak of hepatitis was demonstrated to be related to cross contamination during plasma donation.

A serological study of hepatitis C infection in plasmapheresis donors

An epidemic of parenterally transmitted non-A, non-B hepatitis (PT-NANBH) occurred in plasmapheresis donors in Guan County, Hebei Province, China, in 1985. PT-NANBH was diagnosed by epidemiological studies and serological exclusion of HAV, HBV, CMV and EBV infections. Recently, 163 sera samples of 108 patients with PT-NANBH and 65 sera samples of 49 cases with elevated alanine aminotransferase (ALT) levels collected during the epidemic were tested by anti-HCV EIA (Chiron C100). The positive rates of anti-HCV in these two groups were 89.8% (97/108) and 93.9% (46/49), averaging 90.8%. The figures increased with the course of illness and persistance of ALT elevation, i.e., 17.6% and 55.6% within 1 month, 88.9% and 87.5% at 6 months and 100% and 100% after 2 years. Five patients with PT-NANBH and 1 with elevated ALT levels were followed up for 3 to 4 years. We demonstrated that anti-HCV remained positive after the disease had resolved and ALT levels had normalized.

[Changes of adrenoceptor density in heart and brain and the reactivity of isolated pulmonary artery ring in atherosclerotic rabbit]

The alpha-adrenoceptor density in cerebral cortex and brain stem as well as the beta-adrenoceptor density in heart were measured by radioligand binding assay in normal rabbits (group 1), atherosclerotic rabbits (group 2) and atherosclerotic rabbits treated orally with aspirin 20 mg/kg daily for 16 wk (group 3). The results showed that the beta-receptor density and the KD values of the hearts among the 3 groups and the alpha-receptor density and KD of brain stem between groups 1 and 2 were not significantly different except that the alpha-receptor density in group 3 was decreased slightly. The number of alpha 1-receptor of cerebral cortex was decreased more in group 2 than that in group 3. The contractile responses of isolated pulmonary artery ring by NE were similar among the 3 groups but the reactivity to 5-HT in group 3 was increased significantly.

Metal cations as synaptosomal calcium blockers in studies with Fura-2

Metal ions are often used to block calcium channels in various tissues, including synaptosomes. In the present study, Fura-2 was used to determine the effectiveness of various metal ions as calcium channel blockers in rat brain synaptosomes in vitro. In buffer solutions, La3+ and Cd2+ increased the Fura-2 fluorescence in a manner similar to Ca2+. Ni2+ and Mn2+ appeared to be fluorescence quenching cations, and Sr2+ and Co2+ had little effect on the fluorescence of Fura-2. In suspensions of synaptosomes under resting conditions, Cd2+, Ni2+ and Mn2+ were found to be not suitable for use in synaptosome studies. On the other hand, La3+ and Co2+ had little effect on the Fura-2 fluorescence of resting synaptosomes, and under depolarizing conditions, La3+ and Co2+ decreased the Fura-2 fluorescence. These results, therefore, suggest that La3+ and Co2+ may be suitable as calcium channel blockers in synaptosome studies.