Construction of an alpaca immune antibody library for the selection of nanobodies against Drosophila melanogaster proteins

Introduction: Drosophila melanogaster is a model organism for studying developmental biology and human neural disorders. Nanobodies are the variable domains of the heavy chains of camelid heavy-chain antibodies (VHHs) with high affinity to their antigens and have applications in basic research, similar to traditional antibodies. In addition, nanobodies acting as functionalized antibodies or protein binders have become an additional valuable approach in Drosophila. This study aimed to develop a VHH library against Drosophila proteins and confirm its availability by retrieving some Drosophila protein-specific nanobodies from the library. Methods: An alpaca was first immunized with Drosophila embryo lysate and then its lymphocytes were isolated. Total RNA was extracted and cDNA was synthesized. The vhh sequences were amplified by two round PCR, which were then ligated to a phage display vector pADL-10b. The ligation products were transduced into SS320 competent cells to generate a VHH library. From this library, nanobodies against CG7544, Myc, and CyclinE was enriched and screened by phage display technology and ELISA. DNA sequences of identified nanobodies were cloned into pADL-10b-Flag-His for expression and purification in Escherichia coli SS320. Binding ability of purified nanobodies with corresponding antigens were determined by ELISA and surface plasmon resonance in vitro. Results: In this study, an immune VHH library against Drosophila embryo proteins was generated with a capacity of 3 × 10⁷. From this library, eight nanobodies against three Drosophila proteins, Myc, CyclinE, and CG7544, were identified and the DNA sequences of these nanobodies were obtained. These nanobodies were successfully expressed and purified from Escherichia coli SS320, and were demonstrated to bind corresponding antigens with high affinity in vitro. Moreover, the equilibrium constant between the highest enriched nanobodies and corresponding antigens were calculated. Conclusion: In summary, we report the availability of an immune VHH library and a highly efficient panning strategy for nanobodies against proteins in Drosophila.

[Clinical features and spinal lesions in patients with chronic prostatitis/chronic pelvic pain syndrome]

Objective: To analyze the clinical features and spinal lesions related to micturitionin of chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS) patients. Methods: Patients with CP/CPPS were enrolled to this study at the outpatient department of Tongji Hospital between January and June 2019. The data of clinical features was collected and analyzed, including lower urinary tract symptoms(LUTS), bowel syndrome and pain over different parts of body, as well as lower urinary tract dysfunction, spinal lesions and pelvic organ morphological changes demonstrated by MRI. The potential role of spinal lesions in the development of CP/CPPS syndrome was investigated. Results: A total of 126 CP/CPPS patients were included, with an age［M（Q₁，Q₃）］of 41(31,53) years and a course of disease of 2(1,20) years. Among them, 126 (100.0%) were complicated with LUTS, 72(57.1%) with bowel dysfunction and 88(69.8%) with pain. MRI showed the cervical central disc herniation(126 cases, 100.0%), the ischemic changing in the cervical area of visceral efferant pathway(82 cases, 65.1%), the lumbar central disc herniation(65 cases, 51.6%), and the sacral nerve cysts(97 cases, 77.0%) are commonly seen. In addition, the morphological changes in the visceral organs containing smooth muscle were demonstrated, including thickened bladder wall(91 cases, 72.2%), distended seminal vesicles(70 cases, 55.6%) and distended sigmoid colon/rectum(59 cases, 46.8%). Conclusions: CP/CPPS patients were characterized by the co-existence of LUTS, bowel dysfunction and somatic pain in one individual. The presence of multi-organ symptoms, combined with the high prevalence of spinal lesions associated with micturition reflex, suggesting the potential role of the spinal lesions in the development of CP/CPPS.

Overexpression of zinc-finger protein 677 inhibits proliferation and invasion by and induces apoptosis in clear cell renal cell carcinoma

Recent studies have demonstrated that zinc-finger protein 677 (ZNF677) acts as a tumor suppressor gene in cancer. However, the expression and function of ZNF677 in clear cell renal cell carcinoma (ccRCC) are still unclear. In this study, we used bioinformatics analysis and in vitro experiments to investigate the expression of ZNF677 in ccRCC tissues and the malignant biological behavior of ZNF677 in 786–0 cells. We demonstrated that ZNF677 is hypermethylated in ccRCC and is associated with clinicopathological features. The results of the functional assays indicate that ZNF677 inhibits tumor cell proliferation and invasion and induces apoptosis. Further prognostic analysis indicated that low expression of ZNF677 is associated with shorter overall survival. Additionally, ZNF677 overexpression suppressed the invasion and epithelial-mesenchymal transition of 786–0 cells by inactivating the PI3K/AKT signaling pathway. This is the first report to evaluate the influence of ZNF677 on ccRCC cells malignant biological behavior. The results indicate that high expression of ZNF677 could be considered as a favorable prognostic indicator for ccRCC.

[Estimation of newly HIV infection trend by using the back-calculation method in Honghe Hani and Yi autonomous prefecture]

Objective: Using the changing patterns of CD(4)(+) lymphocytes (CD(4)) counts of HIV/AIDS cases, we tried to estimate the number of newly infected HIV in Honghe Hani and Yi autonomous prefecture (Honghe prefecture) Yunnan province, and to provide reference for evaluating the trend of local HIV epidemic. Methods: Among diagnosed HIV infections, those who were at ≥15 years old, having available initial CD(4) records of testing, initiating antiviral therapy before the end of 2018, were selected from the case reporting system of Honghe prefecture, Yunnan province. Both Depletion model of the square root on CD(4) and the time of infection were used to back-calculate the seroconversion time of each individual. Both direct probability distribution method and life table method were used to calculate the distribution rates of diagnosis and the weight of delay. The number of diagnoses over the years was used to reversely estimate the total number of newly HIV infections. Results: At the end of 2018, the total number of HIV infections was estimated 35 977 with the rate of diagnosis as 77.50% in Honghe prefecture of Yunnan province. The number of new HIV infections appeared as 23 792 in 2008-2018. Cumulatively, the number of new HIV infections was 12 185 up to 2007. The estimated number of new HIV infections decreased from 2 602 in 2008 to 1 480 in 2018. The weight of diagnostic delay decreased from 5.49 in one year to 1.00 in 20 years, and the diagnosis rate increased from 18.2% to 100.0% during 20 years. Conclusion: In Honghe prefecture of Yunnan province, the number of newly infection showed a declining trend but the diagnostic rate was still far from reaching the "first 90% target" . It is expected to expand the timeliness on detection and case-finding so as to reduce the risk of HIV transmission.

[Progress of research on the susceptibility of HIV infection among heterosexual partners of men who have sex with men]

Affected by internal and external factors, more than 70.0% of men who have sex with men (MSM) have the intention to get married, and more than 90.0% of MSM view marriage as inevitable. Due to the marriage, there merges a group of women who are heterosexual partners of MSM and also known as'tongqi' (TQ). Because MSM is a high-risk group infected with HIV, together with the existence of other predisposing factors, the TQ population is also under increased risk of HIV infection. This article summarizes the definition, population scale, physical health problems, and risk factors of HIV infection among TQ with the purpose of providing evidence for the implementation on the follow-up prevention and control programs of sexually transmitted diseases for the TQ population.

[Application of Bayesian statistics in AIDS epidemic estimation]

With the prevalence of AIDS in countries around the world, the epidemic has affected more areas and more populations, and the epidemic pattern is more complicated, so the methods for estimating and predicting AIDS epidemic need to be improved continuously. The existing mathematical statistics models and computer software prediction methods of AIDS epidemic have their own advantages and disadvantages, combination and mutual corroboration of different epidemiological estimation methods can facilitate the comprehensive assessment of the AIDS epidemic. This paper summarizes the thinking, development, application and precautions of Bayesian statistics in AIDS epidemic estimation to provide reference for the further application of Bayesian statistics in AIDS epidemic estimation.

[Sacral neuromodulation preliminary outcomes in male patients with idiopathic dysuria]

Objective: To assess the effectiveness and safety of sacral neuromodulation (SNM) therapy for men with idiopathic dysuria. Methods: From January 2012 to December 2016, a total of 26 patients treated with SNM therapy from multi-center across the country were retrospectively studied. The age ranged from 19 to 86 years with an average age of 45.2 years. Patients suffered from one or multiple urinary symptoms such as frequency of urination, urgency, urinary retention, etc. All patients had received more than two types of conservative therapy including oral and behavioral therapy, but had poor or no improvement. The voiding diary, urgency score and the quality of life score before implantation, in stageⅠ after implantation and stage Ⅱ after permanent implantation were recorded and compared. Results: A total of 22 patients chose to receive IPG at the end of stageⅠ therapy while 4 patients refused further stage Ⅱ therapy because of dissatisfactory effect. The conversion rate of stage Ⅰ to stage Ⅱ was 84.6% (22/26). The average follow-up time was 19.2 months, ranging from 3 to 63 months. The baseline of residual urine, voiding frequency and average voiding amount and those after stage Ⅰ therapy were [5 (0, 137.5) ] ml vs [0 (0, 40) ] ml, 14.6±6.1 vs 9.1±2.8, [100 (80, 135) ] ml vs [190 (150, 210) ] ml, respectively. The differences were statistically significant(all P<0.05).However, no significant differences were found in urination volume and quality of life (QoL) before and after implantation(P>0.05). During an average follow-up time of 19.2 months after the permanent implantation, over 80% patients had an improvement of residual urine volume by more than 50% after permanent implantation while the improvement was 55.6% after stage Ⅰ therapy, suggesting that the improvement of residual urine volume might be positively correlated with the duration of regulation. No significant differences were found in other parameters between stage Ⅰ and Ⅱ therapy. No adverse events like wound infection and electrode dislocation happened during our study. Conclusions: SNM is an effective and safety procedure for male patients with idiopathic dysuria, with a relatively high transfer rate. The medium-term curative effect is stable. The duration of regulation may be positively correlated with the improvement of residual urine.

The MTHFR polymorphism affect the susceptibility of HCC and the prognosis of HCC liver transplantation

BACKGROUND

Methylenetetrahyfrofolate reductase (MTHFR) is the key enzyme for one carbon and folate metabolism. Previous studies have drawn different conclusions about the relationship between the mutation of MTHFR and hepatocellular carcinoma (HCC) occurrence. MTHFR polymorphisms' influence on liver transplantation for HCC recurrence has yet not been reported. Aim of this study was to clarify the impact of MTHFR polymorphism on hepatocarcinogenesis and the prognosis of liver transplant recipient with HCC.

METHODS

This study enrolled 244 HCC patients and 487 healthy individuals in Chinese Han population to analyze the influence of MTHFR polymorphism on HCC susceptibility first. Furthermore, this research choose another 100 donors' and 104 recipients' specimens to detect the association between polymorphism of MTHFR and post-transplant HCC recurrence.

RESULT

rs1801131 polymorphism A to C was associated with the occurrence of HCC in Chinese Han population (p < 0.05), especially in age exceeding 50 years (p < 0.01). No association was observed with rs1801133 polymorphism and HCC occurrence. The mean tumor-free survival for recipients with donor liver graft rs1801133 C to T variants was shorter than CC type (12.63 ± 3.84 vs 22.43 ± 4.74 months, p < 0.05). Multivariate analysis revealed that Donor rs1801133 and Hangzhou criteria were two independent prognostic factors for tumor-free survival (p < 0.05). Neither donor rs1801131 polymorphism nor recipients' MTHFR polymorphisms was associated with HCC recurrence.

CONCLUSION

This study demonstrated that MTHFR polymorphism was associated with HCC occurrence and post-transplant HCC recurrence. rs1801131 mutation A to C is a valuable molecular biomarker for predicting HCC occurrence in Chinese Han population. Donor MTHFR rs1801133 C to T polymorphism could present as a promising prognostic biomarkers for HCC recurrence in liver transplant recipients.

Donor Graft MicroRNAs: A Newly Identified Player in the Development of New-onset Diabetes After Liver Transplantation

New-onset diabetes after liver transplantation (NODALT) is a frequent complication with an unfavorable outcome. We previously demonstrated a crucial link between donor graft genetics and the risk of NODALT. We selected 15 matched pairs of NODALT and non-NODALT liver recipients using propensity score matching analysis. The donor liver tissues were tested for the expression of 10 microRNAs (miRNAs) regulating human hepatic glucose homeostasis. The biological functions of potential target genes were predicted using gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Both miR-103 and miR-181a were significantly highly expressed in the NODALT group as compared to the non-NODALT group. The predicted target genes (e.g. Irs2, Pik3r1, Akt2, and Gsk3b) were involved in glucose import and the insulin signaling pathway. We also observed dysregulation of miRNAs (e.g. let-7, miR-26b, miR-145, and miR-183) in cultured human hepatocytes treated with tacrolimus or high glucose, the two independent risk factors of NODALT identified in this cohort. The hepatic miRNA profiles altered by tacrolimus or hyperglycemia were associated with insulin resistance and glucose homeostatic imbalance as revealed by enrichment analysis. The disease susceptibility miRNA expressive pattern could be imported directly from the donor and consolidated by the transplant factors.

New Insights Into Roles of Ubiquitin Modification in Regulating Plastids and Other Endosymbiotic Organelles

Recent findings have revealed important and diverse roles for the ubiquitin modification of proteins in the regulation of endosymbiotic organelles, which include the primary plastids of plants as well as complex plastids: the secondary endosymbiotic organelles of cryptophytes, alveolates, stramenopiles, and haptophytes. Ubiquitin modifications have a variety of potential consequences, both to the modified protein itself and to cellular regulation. The ubiquitin-proteasome system (UPS) can target individual proteins for selective degradation by the cytosolic 26S proteasome. Ubiquitin modifications can also signal the removal of whole endosymbiotic organelles, for example, via autophagy as has been well characterized in mitochondria. As plastids must import over 90% of their proteins from the cytosol, the observation that the UPS selectively targets the plastid protein import machinery is particularly significant. In this way, the UPS may influence the development and interconversions of different plastid types, as well as plastid responses to stress, by reconfiguring the organellar proteome. In complex plastids, the Symbiont-derived ERAD-Like Machinery (SELMA) has coopted the protein transport capabilities of the ER-Associated Degradation (ERAD) system, whereby misfolded proteins are retrotranslocated from ER for proteasomal degradation, uncoupling them from proteolysis: SELMA components have been retargeted to the second outermost plastid membrane to mediate protein import. In spite of this wealth of new information, there still remain a large number of unanswered questions and a need to define the roles of ubiquitin modification further in the regulation of plastids.

Statins and the brain: New perspective for old drugs

Statins are one of the most popular lipid-lowering drugs (LLDs). Upon oral administration, these drugs are well absorbed by the intestine and effectively used for the treatment of dyslipidemias. Recently, statins are becoming also well-known for their cholesterol-independent effects and their potential use in brain diseases and different types of cancers. While still controversial, recent research has suggested that statin's cholesterol-independent activities work possibly through alterations on isoprenoid levels. This reduction of isoprenoids in the central nervous system might result in effective biochemical and behavioral improvements on certain neurological disorders. This manuscript aims to highlight current research describing the use of statin therapy in the brain and discuss whether statins might affect neuronal dynamics and function independently of their cholesterol regulatory role.

Korean red ginseng: a new approach for the treatment of graft-versus-host disease after liver transplantation

BACKGROUND

Graft-versus-host disease (GVHD) is a rare complication after liver transplantation with an extremely poor prognosis; its occurrence offers great challenges.

METHODS

We have reported herein one case of acute GVHD after liver transplantation who was treated with a traditional Chinese medicine named Korean Red Ginseng (KRG).

RESULTS

The acute GVHD was successfully cured by KRG.

CONCLUSIONS

The successful salvage of acute GVHD after liver transplantation by KRG may provide a new viable therapeutic option.

Expression of aquaporin 4 and Kir4.1 in diabetic rat retina: treatment with minocycline

This study examined aquaporin 4 (AQP4) and Kir4.1 (a potassium channel subunit) in normal and diabetic adult Sprague-Dawley rats, and determined the effect of minocycline treatment. Retinal expression of the AQP4 and Kir4.1 genes was examined using double immuno fluorescence, Western blot analysis, and real-time reverse transcription-polymerase chain reaction. Retinal levels of vascular endothelial growth factor (VEGF), ionized calcium-binding adaptor molecule (Iba)-1 and interleukin (IL)-1β were also ascertained. The blood-retinal barrier (BRB) and retinal oedema were assessed using rhodamine isothiocyanate. AQP4, VEGF, Iba-1, and IL-1β mRNA and protein levels increased, and Kir4.1 mRNA and protein levels decreased, in diabetic rat retinas. Both BRB disruption and retinal oedema were also observed in these retinas. In diabetic rats, minocycline treatment decreased AQP4, VEGF, Iba-1 and IL-1β levels and retinal oedema, and increased Kir4.1 levels. These findings suggest that minocycline might be beneficial for retinal fluid clearance and reduction of retinal oedema in diabetic retinopathy.

Calmodulin-binding protein BP-10, a probable new member of plant nonspecific lipid transfer protein superfamily

CaMBP-10 is a novel plant endogenous calmodulin-binding protein with important physiological functions. The partial cDNA sequence of this protein was cloned using RT-PCR. The deduced peptide (designated PCBP10) is composed of 74 amino acid residues containing a basic amphiphilic alpha-helix typical for calmodulin-binding proteins. PCBP10 shows very high amino acid sequence homology with plant nonspecific lipid-transfer proteins (nsLTPs). Sequence analysis also reveals that PCBP10 has similar amino acid composition to plant nsLTPs, and seven of the eight conserved cysteine residues are found in PCBP10. Furthermore, the secondary structure features of PCBP10 are very similar to those of plant nsLTPs. In addition, there are striking resemblances between CaMBP-10 and plant nsLTPs in their biochemical and physical properties. Our results suggest that CaMBP-10 is a novel member of the plant and nsLTP gene family, and the Ca(2+)/CaM regulative system may also play roles in lipid metabolism, defense reactions, and the adaptation of plants to natural environment.

[Experimental colitis induced by dextran sulfate sodium]

In this study, experimental colitis in rats induced by dextran sulfate sodium (DSS) was performed. Twenty rats freely drank 3% DSS solution for 10 days. During the 10 days, symptoms (diarrhea, hemafecia) were observed daily, and at the same time the rats were colon-endoscopied. After that these rats were killed and their cola taken out to be examined grossly and histologically. It was found that colitis induced by DSS was similar to human ulcerative colitis in symptoms and in pathological changes.

[The clinic significance of serum hyaluronate and tumor necrosis factor alpha levels in liver diseases]

Serum levels of hyaluronic acid (HA) and tumor necrosis factor alpha (TNF alpha) in 94 patients with various liver diseases and 31 healthy controls were studied by RIA, Serum TNF alpha in hepatitis, liver cirrhosis (LC) and primary hepatic carcinoma (PHC) was higher than that of the control. Serum HA in chronic hepatitis, LC and PHC was higher than that in the control. The serum level of HA showed a positive correlation with the serum level of TNF alpha. It is considered that the increase of serum HA indicates an early fibrogenic tendency in patients with liver diseases. TNF alpha is involved in the formation of hepatic fibrosis.

Sex differences and phases of the estrous cycle alter the response of spinal cord dynorphin neurons to peripheral inflammation and hyperalgesia

The neuromodulatory interactions of sex steroids with the opioid system may result in sex differences in pain and analgesia. Dynorphin is an endogenous kappa-opioid peptide that is upregulated in an animal model of peripheral inflammation and hyperalgesia and is possibly regulated by circulating levels of sex steroids. The present study compared behavioral responses of male, cycling female, and gonadectomized Sprague-Dawley rats in a model of persistent pain. Cycling female rats were behaviorally tested over a 14-day period, and their estrous cycles were monitored by daily vaginal smears. Thermal hyperalgesia was measured by paw withdrawal latencies taken prior to and 24-72 h after rats received a unilateral hindpaw injection of complete Freund's adjuvant (CFA). Prior to CFA administration, there was no significant difference in paw withdrawal latencies between male rats, cycling female rats, and ovariectomized female rats. Following CFA administration, female rats in proestrus exhibited significantly increased hyperalgesia compared with male rats, ovariectomized female rats, and female rats in other estrous stages (P</=0.05). Levels of spinal preprodynorphin (PPD) mRNA induction in the L4-L5 segments were assessed by Northern blot analysis. PPD mRNA expression ipsilateral to the injected paw was significantly higher in female rats in diestrus (P</=0.05) and proestrus (P</=0.01) compared with rats in estrus and intact male rats. Ovariectomized rats had significantly higher levels of PPD mRNA expression compared with intact male rats (P</=0.05). However, castrated male rats had significantly lower levels of PPD mRNA expression than intact male rats (P</=0.05). PPD mRNA expression was not altered on the contralateral side of the spinal cord in any group. These results suggest a hormonal regulatory influence on the response of spinal cord dynorphin neurons to chronic inflammation and furthermore, that the association of the endocrine and opioid systems have the ability to influence an animal's sensitivity to pain.

Inhibition of endothelial cell thromboresistance by homocysteine

Homocysteine (HC) is a highly reactive thiol intermediate in amino acid metabolism, which can modify the function of endothelial cells in a myriad of ways. In vitro, homocysteine can inhibit the thromboresistance properties of the endothelial cell by induction of procoagulant factors, inactivation of natural anticoagulant systems, and suppression of vasodilatory and platelet-modulating factors. HC also inhibits the fibrinolytic system by impairing the ability of the endothelial cell to bind tissue plasminogen activator (t-PA), by interacting directly with the t-PA binding "tail" domain of its endothelial cell receptor, annexin II. Moreover, HC influences endothelial cell gene expression as exemplified by induction of the elongation factor-1 family of polypeptides, which promote polypeptide chain elongation during mRNA translation. Induction of EF-1 subunits alpha, beta, gamma and delta by homocysteine is associated with increased turnover of at least one free thiol-containing protein, suggesting that up-regulation of these subunits may represent a mechanism for replacement of damaged or modified proteins. A more complete understanding of the diverse effects of homocysteine on endothelial cell function may provide important clues to the precise role homocysteine may play in the initiation and progression of vascular disease.

[Clinical application of chromosome haplotype analysis and mutation analysis to the diagnosis of Wilson's disease]

OBJECTIVE

To set up the method of gene diagnosis of Wilson's disease (WD) by chromosome haplotype analysis and mutation detection.

METHODS

This study selected 3 (CA)n repeat genetic markers,D13S316, D13S133 and D13S314 to construct the chromosome haplotype within 8 Han WD families. PCR-SSCP was used to reconfirm the diagnosis of the siblings of the probands in the families where in the disease-causing mutation had been detected.

RESULTS

One asymptomatic WD patient and 5 heterozygotes were detected.

CONCLUSION

In the WD families, the analysis of chromosome haplotype helps to make the diagnosis of siblings of the probands;for the WD families in which the disease-causing mutation has been ascertained, mutation analysis can provide direct and definite evidence for diagnosis. The combination of these two methods can provide more evidences for diagnosis.

Effects of losartan and PD123319 on antigensin II-induced proto-oncogene expression and protein synthesis in cultured neonatal rat cardiac myocytes

To study the effects of specific angiotension II (Ang II) receptor, type-1 (AT1) antagonist (Losartan) and type-2 (AT2) antagonist (PD123319), on Ang II-induced proto-oncogene expression and synthesis of RNA and protein in neonatal rat cardiac myocytes, we used respectively [3H]-uridine and [3H]-leucine incorporation to measure the rate of RNA and protein synthesis, and analyzed the c-myc mRNA level by Northern blot. We found that an acceleration in the rate of RNA and protein synthesis was observed when exposed to 2.5 x 10(-6) mol.L-1 [Sar1] Ang II for 24 h (P < 0.01). Losartan inhibited the action in a dose-dependent manner. The level of c-myc mRNA was up-regulated to 340% of control by 2.5 x 10(-6) mol.L-1 Ang II, and Losartan (10(-5) mol.L-1) suppressed the increase of c-myc mRNA stimulated by Ang II. PD123319 showed similar inhibition on Ang II-induced RNA and protein synthesis, but did not inhibit c-myc expression. Thus, Ang II-stimulated expression of c-myc is mainly mediated by AT1 receptors, and contributes to cardiac myocyte hypertrophy while AT2 receptors are involved in mediation of cellular growth without altering of c-myc expression.

Induction of acute translational response genes by homocysteine. Elongation factors-1alpha, -beta, and -delta

The thiol amino acid homocysteine (HC) accumulates in homocystinuria and homocyst(e)inemia, and is associated with a wide variety of clinical manifestations. To determine whether HC influences the cell's program of gene expression, vascular endothelial cells were treated with HC for 6-42 h and analyzed by differential display. We found a 3-7-fold, time-dependent induction of a 220-base pair fragment, which demonstrated complete sequence identity with elongation factor-1delta (EF-1delta), a member of the multimeric complex regulating mRNA translation. Fibroblasts from cystathionine beta-synthase -/- individuals also showed up to 3.0-fold increased levels of mRNA for EF-1alpha, -beta, and -delta when compared with normal cells, and treatment of normal cells with the HC precursor, methionine, induced a 1.5-2.0-fold increase in EF-1alpha, -beta, and -delta mRNA. This induction was completely inhibited by cycloheximide and reflected a doubling in the rate of gene transcription in nuclear run-on analyses. In HC-treated endothelial cells, pulse-chase studies revealed a doubling in the rate of synthesis of the thiol-containing protein, annexin II, but no change in synthesis of the cysteineless protein, plasminogen activator inhibitor-1. Thus, HC induces expression of a family of acute translational response genes through a protein synthesis-dependent transcriptional mechanism. This process may mediate accelerated synthesis of free thiol-containing proteins in response to HC-induced oxidative stress.

The identification of 5 alpha-reductase-2 and 17 beta-hydroxysteroid dehydrogenase-3 gene defects in male pseudohermaphrodites from a Turkish kindred

Male pseudohermaphroditism (MPH) is characterized by incomplete differentiation of male genitalia in the presence of testicular tissue. Enzymatic defects involving androgen synthesis or action are causes of MPH. We studied the molecular genetics of a large isolated inbred Turkish kindred with MPH due to either 5 alpha-reductase-2 (SRD5A2) or 17 beta-hydroxysteroid dehydrogenase-3 (17 beta HSD3) gene defects. Using single strand DNA conformational polymorphism analysis and DNA sequencing, a new mutation in exon 5 of SRD5A2 gene was detected in certain male pseudohermaphrodites from this kindred. This single base deletion (adenine) resulted in a frame shift at amino acid position 251 resulting in the addition of 23 amino acids at the carboxyl-terminal of this 254-amino acid isozyme. Transfection expression of the mutant isozyme in CV1 cells showed a complete loss of enzymatic activity in the conversion of [14C]testosterone to dihydrotestosterone, without a change in the messenger ribonucleic acid level compared to that of the wild-type isozyme. Analysis of the 17 beta HSD3 gene in other male pseudohermaphrodites from this kindred revealed a single point mutation (G-->A) at the boundary between intron 8 and exon 9, disrupting the splice acceptor site of exon 9. In this kindred, in addition to the identification of male pseudohermaphrodites with either a homozygous SRD5A2 or 17 beta HSD3 gene defect, other male pseudohermaphrodites were found to be genetically more complex: e.g. homozygous for the SRD5A2 defect and heterozygous for the 17 beta HSD3 defect, or homozygous for the 17 beta HSD3 defect and heterozygous for the SRD5A2 defect. Also, phenotypically normal carriers were identified with either one or both gene defects. Homozygous male pseudohermaphrodites with SRD5A2 or 17 beta HSD3 gene defects were phenotypically distinguishable by the presence of mild gynecomastia in the latter. Hormone data were consistent with the particular homozygous gene defect. In summary, we show 1) the novel existence of two gene defects, SRD5A2 and 17 beta HSD3, each causing MPH within a large isolated Turkish kindred; 2) that the two defects segregate independently and may be inherited from two different progenitors; and 3) analysis of a new mutation in exon 5 of SRD5A2 gene, supporting the functional importance of the carboxyl-terminal of 5 alpha-reductase-2 isozyme.

Inhibition of beta-myosin heavy chain gene expression in pressure overload rat heart by losartan and captopril

AIM

To study the effects of losartan and captopril on beta-myosin heavy chain (MHC), and alpha-MHC gene expression.

METHODS

Pressure overload was produced by abdominal aortic coarctation (AAC) in rats. alpha- and beta-MHC mRNA were measured by Northern blot.

RESULTS

In left ventricular myocardium of sham-operated rats, the alpha-MHC mRNA predominated, while the beta-MHC mRNA was only detectable. In response AAC, there was a 70-fold increase in the beta-MHC mRNA (P < 0.01), while alpha-MHC mRNA reduced to 26% (P < 0.01). Losartan (3 mg.kg-1.d-1, i.g. for 11 d) to AAC rats caused inhibitions of beta-MHC by 96% and alpha-MHC by 86% gene expression without lowering blood pressure. A reduction in beta-MHC mRNA was also seen in captopril-treated rats (30 mg.kg-1.d-1, i.g. for 11 d), but the inhibitory effect of captopril on alpha-MHC mRNA was less than that of losartan (44% vs 86%, P < 0.05).

CONCLUSIONS

The shift of MHC isoform induced by pressure overload is due to up-regulation of beta-MHC and down-regulation of alpha-MHC gene expression. Inhibition of beta-MHC gene expression by losartan is achieved primarily by direct blockade of angiotensin II type I receptors in the myocardium, independent on hemodynamics.

Effects of endocardial endothelium in myocardial mechanics of hypertrophied myocardium of rats

AIM

To investigate the effects of endocardial endothelium (EE) in myocardial mechanics of hypertrophied myocardium of rats.

METHODS

Hypertrophied myocardium has been developed through long-term renovascular hypertension in rats. Selective stripping of EE was achieved chemically and the effects of EE on the activation and relaxation of hypertrophied myocardium were investigated and compared to those in the presence and absence of intact EE.

RESULTS

Resting tension (RT) and peak developed tension (DT) of isometric contraction of the left ventricular papillary muscles of renovascular hypertensive rats (RHR) remained similar, but maximal rate of tension development and fall (+dT/dtmax and -dT/dtmax) were lowered, time to +dT/dtmax (TPP) and time to -dT/dtmax (TPN) were increased, and time to peak developed tension (TPT) and half relaxation time (RT1/2) were prolonged, vs sham-operated rats (Sham). After EE denudation, TPT, and RT1/2 were significantly abbreviated in RHR. The -dT/dtmax was significantly augmented while the +dT/dtmax was unaltered, resulting in a prominent decrease in the ratio of +dT/dtmax to -dT/dtmax.

CONCLUSION

EE predominantly influences the relaxation in isolated myocardium and early diastolic filling events in hearts, and is involved in the cardiac compensatory mechanism in hypertrophied myocardium.

Effects of lysophosphatidylcholine on bovine aortic endothelial cells in culture

To elucidate the vascular actions of lysophosphatidylcholine, we examined its effects on the concentration of cytosolic free calcium ([Ca2+]i), plasma membrane fluidity and release of lactate dehydrogenase in vascular endothelial cells cultured from bovine aortas. The [Ca2+]i of the endothelial cells was measured by a dual-wavelength fluorospectrophotometer using a fluorescent, calcium-specific indicator, Fura-2. Membrane fluidity was monitored by measuring changes in the steady-state fluorescence anisotropies, using 1,6-diphenyl-1,3,5-hexatriene as a fluorescence probe. In the presence of 1 mmol/L extracellular calcium, lysophosphatidylcholine caused a biphasic elevation of [Ca2+]i in Fura-2-loaded vascular endothelial cells, consisting of a large transient component followed by a relatively low, but more sustained component. At concentrations of lysophosphatidylcholine equal to or greater than 10 mumol/L, [Ca2+]i increased in a dose-dependent manner in the presence or absence of external calcium. In the absence of extracellular calcium, only an initial transient increment in the [Ca2+]i of endothelial cells was generated, the sustained component being eliminated. The sustained component was greatly depressed or almost abolished by the addition of the calcium influx blocker, NiCl2. Plasma membrane fluidity was greatly increased by incubation with lysophosphatidylcholine (30 and 50 mumol/L) concomitant with significant increases in the release of lactate dehydrogenase from the cells. At 50 mumol/L, lysophosphatidylcholine increased lactate dehydrogenase release and membrane fluidity in a time-related way.(ABSTRACT TRUNCATED AT 250 WORDS)

Endocardial endothelium selectively modifies relaxation in rat papillary muscle

The selective removal of endocardial endothelium of rat left ventricular papillary muscles by 1-second immersion in 0.5% Triton X-100 showed little influence on resting tension and only a small decrease in peak isometric tension (8.3 +/- 1.4 vs 9.6 +/- 2.4 mN/mm2 at Lmax, p > 0.05) with no reduction in maximal rate of tension development (+dT/dtmax; 136 +/- 21 vs 137 +/- 18 mN/mm2/s, p > 0.05). In contrast, there was a marked increase in maximal rate of tension decline (-dT/dtmax) from 71 +/- 14 to 92 +/- 15 mN/mm2/s (p < 0.05), so that the ratio between +dT/dtmax and -dT/dtmax fell from 1.98 +/- 0.27 to 1.51 +/- 0.13 (p < 0.01). Removal of endocardial endothelium led to a significant shortening of isometric twitch contractions. Time to peak tension was abbreviated from 111 +/- 20 to 84 +/- 8 ms (p < 0.05) and the half relaxation time from 92 +/- 9 to 68 +/- 8 ms (p < 0.01). Time to +dT/dtmax was also shortened from 31 +/- 6 to 44 +/- 9 ms (p < 0.05) and time to -dT/dtmax from 90 +/- 12 to 62 +/- 10 ms (p < 0.01). These effects were not influenced by alterations in stimulation frequency or muscle length. The early onset of relaxation and abbreviated duration of relaxation together with an increased rate of decline in tension led to a shorter total twitch which may explain the slightly lower peak tension once the endocardial endothelium was removed. Our findings confirm that endocardial endothelium modulates myocardial contraction, with a predominant influence on relaxation.

Regression of cardiac hypertrophy and myosin isoenzyme patterns by losartan and captopril in renovascular hypertensive rats

To test the effect of losartan and captopril on cardiac hypertrophy and myosin isoenzyme, two-kidney, one-clip (2K 1C) renovascular hypertensive rats (RHR) were used. Eight weeks after the onset of hypertension, losartan 5 mg.kg-1.d-1 and captopril 50 mg.kg-1.d-1 were administered p.o. to 2 groups of RHR, respectively for 8 wk. The results showed that captopril significantly decreased the cardiac mass (607 +/- 169 mg vs 1029 +/- 132 mg) and total protein content (120 +/- 38 mg vs 198 +/- 31 mg), concomitant with significant decrease of arterial blood pressure (BP) (15.4 +/- 5.2 kPa vs 28.5 +/- 4.9 kPa). Losartan also induced a significant decrease in cardiac mass (671 +/- 116 mg vs 1029 +/- 132 mg) and protein content (142 +/- 29 mg vs 198 +/- 31 mg), as well as significantly lowered the BP (15.2 +/- 2.1 kPa vs 28.5 +/- 4.9 kPa). It is important to be note that both drugs normalized the shift of myosin isoenzyme in RHR. These results indicated that both drugs, having potent antihypertensive effects, can effectively reverse the cardiac hypertrophy and abnormal distribution of myosin isoenzyme patterns.

Direct method for detecting small quantities of hepatitis B virus DNA in serum and plasma using the polymerase chain reaction

Serum components inhibit DNA polymerase, thereby obviating direct detection of serum viral DNA sequences by the polymerase chain reaction (PCR). This has necessitated extraction of nucleic acid from sera before performing PCR and has resulted in loss of sensitivity. By adsorbing virus to a solid surface (microcentrifuge tubes or antibody coated microparticles) followed by proteinase K digestion, as little as three viruses per 200 microliters serum may be directly detected by PCR without nucleic acid extraction. The sensitivity is dependent on the surface area of the adsorptive surface and is increased by having antibodies on the adsorptive surface. The nucleic acid sequence of the amplified DNA fragments may be directly determined by the dideoxy method. Of 24 plasma samples from HBsAg+ volunteer blood donors, HBV DNA was detected in 7 by dot blot assay, 7 by liquid hybridization, and 9 by PCR. PCR detected DNA in every sample that was positive by another assay. Analysis of serial samples of two patients with acute self-limited hepatitis B found detectable HBsAg and pre-S2 antigenemia before HBV DNA by the PCR method. These results suggest that surface antigenemia may precede viremia during acute hepatitis.

Rett syndrome in China: report of 9 patients

This is the first report of Rett syndrome in China. Clinical and laboratory data were obtained from 9 girls with Rett syndrome. In addition to the previously reported clinical manifestations (i.e., early deterioration of intelligence, microcephaly, peculiar stereotypic hand movements, and epilepsy), 2 other features were observed in these patients: abnormal evoked response audiometry and low content of the elements, copper and zinc in the hair. The cause of these associated phenomena is unknown.