[Analysis of a child with developmental disorder and epilepsy due to a homozygous variant of SLC25A12 gene].

OBJECTIVE: To explore the genetic basis for a child featuring global developmental delay and epilepsy. METHODS: A child who had presented at Guangzhou Women and Children's Medical Center Liuzhou Hospital on February 19, 2023 was selected as the study subject. Clinical data of the child was collected. The child was subjected to whole exome sequencing, and candidate variant was validated by Sanger sequencing and bioinformatic analysis. RESULTS: The child, an 8-month-old girl, had manifested with global developmental delay, epilepsy, and hyperlactacidemia. Cranial MRI revealed diverse hypomyelinating leukodystrophies. Electroencephalogram showed slow background activities. Genetic testing revealed that she has harbored a homozygous variant of the SLC25A12 gene, namely c.115T>G (p.Phe39Val), for which both of her parents were heterozygous carriers. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was predicted to be of uncertain significance (PM2_Supporting+PM3_Supporting+PP3_Moderate+PP4_Moderate). I-Mutant v3.0 software predicted that the variant may affect the stability of protein product. CONCLUSION: The homozygous c.115T>G (p.Phe39Val) variant of the SLC25A12 gene probably underlay the pathogenesis of the disease in this child.

[Differences of Three Methods in Determining Ozone Sensitivity in Nanjing].

In recent years， ozone （O3） has become an increasingly important air pollutant in China. Identifying the sensitivity of O3 to the precursors volatile organic compounds （VOCs） and nitrogen oxides （NOx） can help make effective abatement strategies. This study compared three methods for determining O3-VOCs-NOx sensitivity： simulated photochemical indicator values and sensitivity coefficients derived from a three-dimensional air quality model and an observation-based model （OBM）， with a case study involving an O3 pollution event that occurred in Nanjing in late July 2017. The results showed that O3 sensitivity based on the photochemical indicator and sensitivity coefficients demonstrated similar spatial variations （over 50% of the grid cells of Nanjing exhibiting identical O3 sensitivity）. However， sensitivity coefficients identified a larger number of areas within a transitional O3 sensitivity regime， as opposed to the VOCs- or NOx-limited regime identified by the photochemical indicator. The determination of the latter was affected by the adopted threshold values. The OBM relied on the quality of the observational data. For example， positive biases in observed NO2 could lead to an underestimation of O3 sensitivity to NOx with the OBM. During the high pollution period， the three methods exhibited significant disparities. The photochemical indicator tended to suggest the VOCs-limited condition， whereas the OBM and sensitivity coefficients indicated the NOx-limited or transitional regimes.

[Impacts of Anthropogenic Emission Reduction on Urban Atmospheric Oxidizing Capacity During the COVID-19 Lockdown].

In recent years， regional compound air pollution events caused by fine particles （PM2.5） and ozone （O3） have occurred frequently in economically developed areas of China， in which atmospheric oxidizing capacity （AOC） has played an important role. In this study， the WRF-CMAQ model was used to study the impacts of anthropogenic emission reduction on AOC during the COVID-19 lockdown period. Three representative cities in eastern China （Shijiazhuang， Nanjing， and Guangzhou） were selected for an in-depth analysis to quantify the contribution of meteorology and emissions to the changes in AOC and oxidants and to discuss the impact of AOC changes on the formation of secondary pollutants. The results showed that， compared with that in the same period in 2019， the urban average AOC in Shijiazhuang， Nanjing， and Guangzhou in 2020 increased by 60%， 48.7%， and 12.6%， respectively. The concentrations of O3， hydroxyl radical （·OH）， and nitrogen trioxide （NO3·ï¼‰ increased by 1.6%-26.4%， 14.8%-73.3%， and 37.9%-180%， respectively. The AOC in the three cities increased by 0.06×10-4， 0.12×10-4， and 0.33×10-4 min-1， respectively， due to emission reduction. The meteorological change increased AOC in Shijiazhuang and Nanjing by 20% and 17.9%， respectively， but decreased AOC in Guangzhou by -9.3%. Enhanced AOC led to an increase in the nitrogen oxidation ratio （NOR） and VOCs oxidation ratio （VOR） and promoted the transformation of primary pollutants to secondary pollutants. This offset the effects of primary emission reduction and resulted in a nonlinear decline in secondary pollutants compared to emissions during the COVID-19 lockdown.

[Elucidating the Impacts of Meteorology and Emission Changes on Concentrations of Major Air Pollutants in Major Cities in the Yangtze River Delta Region Using a Machine Learning De-weather Method].

This study applied a de-weather method based on a machine learning technique to quantify the contribution of meteorology and emission changes to air quality from 2015 to 2021 in four cities in the Yangtze River Delta Region. The results showed that the significant reductions in PM2.5, NO2, and SO2 emissions(57.2%-68.2%, 80.7%-94.6%, and 81.6%-96.1%, respectively) offset the adverse effects of meteorological conditions, resulting in lower pollutant concentrations. The meteorological contribution of maximum daily 8-h average O3(MDA8_O3) showed a stronger effect than that of others(23.5%-42.1%), and meteorological factors promoted the increase in MDA8_O3 concentrations(4.7%); however, emission changes overall resulted in a decrease in MDA8_O3 concentrations(-3.2%). NO2 and MDA8_O3 decreased more rapidly from 2019 to 2021, mainly because the emissions played a stronger role in reducing pollutant concentrations than from 2015 to 2018. However, emissions changes had weaker reduction effects on PM2.5 and SO2 from 2019 to 2021 than from 2015 to 2018. De-weather methods could effectively seperate the effects of meteorology and emission changes on pollutant trends, which helps to evaluate the real effects of emission control policies on pollutant concentrations.

Analysis on the difference of circulating threshold of polymerase chain reaction in blood screening of external quality assessment / 中国输血杂志

【Objective】 To analyze the difference of circulating threshold (Ct) of polymerase chain reaction (PCR) in blood station laboratories during the external quality assessment, and to put forward suggestions for the quality improvement of participating laboratories. 【Methods】 From 2018 to 2021, the blood station laboratories participated in the external laboratory quality assessment of CITIC including blood screening items with nucleic acid testing method. The data of Roche diagnostic reagent group were used as the source, and the detected Ct values of three groups of quality control samples of HBV A subtype (400 IU/mL), HCV 1b subtype (400 IU/mL) and HIV B genotype (500 IU/mL) were used as the objects. The data were grouped according to quality control (sample) batches, reagent batches and different laboratories. Using the statistical method of variance analysis (assuming P<0.05 as significant), the detected Ct value of each group was analyzed. 【Results】 For the three items (HBV/HCV/HIV), the grouping data involving 42 batches of quality control (13/12/17), 28 batches of reagent (11/8/9) and 57 laboratories (19/19/19) were selected. The grouping analysis of quality assessment batches shows that there was no significant difference between HBV and HCV quality assessment batches, and there was no significant difference between other HIV batches except the two batches of HIV quality assessment samples released in 2021. The grouping analysis of each reagent batch showed that there was no significant difference between each reagent batch for HCV and HIV detection, while there was significant difference between two batches of HBV reagents. After excluding the data groups with significant differences in the quality control batch groups and the reagent batch groups, the detected Ct value of each laboratory group had extremely significant differences in the three items of HBV, HCV and HIV. Through pairing analysis, it was found that four laboratories had significant differences with most other laboratories in the three items, mainly manifested in the high mean value of Ct. 【Conclusion】 For the blood station laboratories with correct test results of quality assessment samples, there are differences in Ct values detected by PCR, which may be mainly caused by the detection ability of the participating laboratories.

External quality assessment of NAT blood screening: an inter laboratory analysis / 中国输血杂志

【Objective】 To summarize and analyze the results of local laboratories participating in China International Transfusion Infection Control (CITIC) Nucleic Acid Testing (NAT) External Quality Assessment (EQA). 【Methods】 The basic situation, test reagents, and abnormal results of 9 domestic laboratories participating in NAT EQA from 2018 to 2020 were collected and analyzed. 【Results】 Among 7 545 testing results, submitted by 48 laboratories using 8 test reagents throughout 9 occasions of CITIC, 64% (4 830/7 545) used imported and 36% (2 715/7 545), domestic reagents. Thirty-one abnormal results were reported, with false negative in 61.29% (19/31), false positive 6.45% (2/31), and others 32.25% (10/31). False negative results only appeared in samples with low viral load of HBV A genotype(40 IU/mL), HCV 1b subtype(40 IU/mL) and HIV B genotype(250IU/mL), relatively concentrated in a few laboratories. The frequency of abnormal results was 0.08 per laboratory per CITIC test. 【Conclusion】 The detection capacity of domestic blood stations has been significantly improved along with the routine NAT practice and regular NAT EQA participation over 5~10 years, but laboratory management still needs to be further strengthened to ensure the reagent testing performance and blood safety.

Pancytopenia and metabolic decompensation in a neonate / 中国当代儿科杂志

A 9-day-old male patient was admitted to the hospital because of cough, anhelation, feeding difficulty and lethargy. The diagnostic examinations indicated pulmonary infection, severe metabolic acidosis, hyperglycemia, hyperammonemia and pancytopenia in the patient. Blood and urine screening and isovaleryl-CoA dehydrogenase (IVD) gene detection for inherited metabolic diseases were performed to clarify the etiology. Tandem mass spectrometric screening for blood showed an elevated isovalerylcarnitine (C5) level. The organic acid analysis of urine by gas chromatography-mass spectrometry showed significantly increased levels in isovaleryl glycine and 3-hydroxyisovaleric acid. Homozygous mutations (c.1208A>G, p.Tyr403Cys) in the IVD gene were identified in the patient. His parents were heterozygous carriers. After the treatment with low-leucine diets and L-carnitine for 3 days, the patient showed a significant improvement in symptoms, but he died one week later. It is concluded that the neonates with pneumonia and metabolic decompensation of unknown etiology should be screened for genetic metabolic disease.

Mitochondrial haplotypes may modulate the phenotypic manifestation of the LHON-associated ND1 G3460A mutation in Chinese families.

To investigate the pathophysiology of Leber's hereditary optic neuropathy (LHON), a cohort of 1164 Han Chinese subjects with LHON were screened for ND1 G3460A mutation. A total of 295 subjects from 16 Han Chinese families carrying the G3460A mutation underwent a clinical and genetic evaluation and molecular analysis of mitochondrial (mt)DNA. The incidence of G3460A mutation was 1.4% in this cohort of Chinese subjects with LHON. Twenty-seven (20 males/7 females) of 109 matrilineal relatives among 10 Chinese pedigrees carrying this mutation exhibited a wide range of severity and age-at-onset in visual impairment. Penetrances of optic neuropathy ranged from 7.1% to 50%, with the average of 24.5%. The age-at-onset of 27 affected matrilineal relatives varied from 10 to 40 years, with the average of 22 years. Molecular analysis identified the homoplasmic G3460A mutation and distinct sets of variants belonging to eight haplogroups. Haplogroup M with G3460A mutation was of higher frequency than those in controls. The penetrances of visual loss in families carrying mitochondrial DNA haplogroups A, B and M were higher than those in other families. Furthermore, haplogroup-specific variants tRNA(Ser(AGY)) A12223G, tRNA(Thr) G15927A and tRNA(Glu) A14693G may enhance the penetrance of visual loss in these families. The G3460A mutation occurred through recurrent origins and founder events in Chinese population. Mitochondrial modifiers may modulate the penetrance and expressivity of optic neuropathy among Chinese pedigrees carrying the G3460A mutation. Thus, our findings may provide new insights into the understanding of pathophysiology and valuable information on the management of LHON.

Coronary heart disease is associated with a mutation in mitochondrial tRNA.

Coronary heart disease (CHD) is the leading cause of death worldwide. Mitochondrial genetic determinant for the development of CHD remains poorly explored. We report there the clinical, genetic, molecular and biochemical characterization of a four-generation Chinese family with maternally inherited CHD. Thirteen of 32 adult members in this family exhibited variable severity and age-at-onset of CHD. Mutational analysis of their mitochondrial genomes identified the tRNA(Thr) 15927G>A mutation belonging to the Eastern Asian haplogroup B5. The anticipated destabilization of a highly conserved base-pairing (28C-42G) by the 15927G>A mutation affects structure and function of tRNA(Thr). Northern analysis revealed ≈80% decrease in the steady-state level of tRNA(Thr) in the mutant cell lines carrying the 15927G>A mutation. The 15927G>A mutation changed the conformation of tRNA(Thr), as suggested by slower electrophoretic mobility of mutated tRNA with respect to the wild-type molecule. In addition, ∼39% reduction in aminoacylated efficiency of tRNA(Thr) was observed in mutant cells derived from this Chinese family. An in vivo mitochondrial protein labeling analysis showed ∼53% reduction in the rate of mitochondrial translation in mutant cells. The impaired mitochondrial protein synthesis leads to defects in overall respiratory capacity or malate/glutamate-promoted respiration or succinate/glycerol-3-phosphate-promoted respiration, or N,N,N',N'-tetramethyl-pphenylenediamine/ascorbate-promoted respiration in mutant cells. An increasing production of reactive oxygen species was observed in the mutant cells carrying the 15927G>A mutation. These results provide the direct evidence that the tRNA(Thr) 15927G>A mutation is associated with CHD. Our findings may provide new insights into pathophysiology and intervention targets of this disorder.

Psychometric properties of the Padua Inventory in Chinese college samples.

The aim of the present study was to investigate the psychometric properties of the Padua Inventory in Chinese college samples. Three different samples (N1 = 1,939, N2 = 1,341, and N3 = 298) of Chinese college students were recruited. Exploratory factor analyses yielded a four-factor structure which was similar to that found in previous studies. Further, present results showed good internal consistency as well as convergent and divergent validity with the subscales of the Symptom Checklist-90 and the Penn State Worry Questionnaire. Although no sex difference was found on total score, women had significantly higher scores on Factor 2 (Urges and worries of losing control over motor behaviors) and Factor 4 (Checking), while men had significantly higher scores on Factor 3 (Contamination). Implications of ter the results and directions for research are discussed.

Effects of gonadotroph-releasing hormone analogues on follicle apoptosis in rats with chemotherapy-induced ovarian damage / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of gonadotroph-releasing hormone (GnRH) agonist (GnRH-a) and GnRH antagonist (GnRH-ant) on cyclophosphamide (CTX)-induced follicle apoptosis in female rats.</p><p><b>METHODS</b>Thirty-six female Sprague- Dawley rats were randomized into 6 groups, namely normal saline (NS), CTX, GnRH-a+NS, GnRH-a+CTX, GnRH-ant+NS, and GnRH-ant+CTX groups. The rats were sacrificed between the first and second week after the treatments., and the follicle apoptosis was investigated using TUNEL assay and transmission electron microscopy.</p><p><b>RESULTS</b>The apoptosis rate of the granulose cells in the follicles in late development was significantly higher than that in early follicles, and the apoptosis rate of the oocytes and granulose cells in rats with CTX treatment was significantly higher than that in rats without CTX treatment (P<0.05). The apoptosis rate of the granulose cells in GnRH-a groups (ranging from 33.40 - or + 4.59 to 73.25 - or + 5.35) was significantly higher than that in GnRH-ant groups (27.46 - or + 4.52 to 49.38 - or + 5.02, P<0.05), but there was no significant difference in the oocytes of early follicles between GnRH-a groups (23.48 - or + 4.25 to 36.15 - or + 4.23) and GnRH-ant groups (21.47 - or + 3.81 to 34.04 - or + 5.54, P>0.05). Electron microscopy revealed characteristic apoptotic changes of the oocytes in early follicles and granulose cells in early and late follicles. The apoptotic changes were especially typical in the granulose cells showing the formation of the apoptotic bodies, and the oocytes only showed chromatin condensation and aggregation.</p><p><b>CONCLUSION</b>In the rat mode, GnRH-a promotes while GnRH-ant suppressed follicle apoptosis induced by CTX. GnRH analogues regulates mainly granulose cell apoptosis, but have little effect on oocyte apoptosis.</p>

Using real-time PCR to evaluate the effect of viral inactivation by Methylene Blue with visible light / 病毒学报

To investigate the feasibility of using Real-Time PCR to evaluate the effectiveness of Sindbis virus inactivation by Methylene Blue with visible light. Sindbis virus was treated by Methylene Blue with different intensity of visible light and the transcribed cDNA was quantified by Real-Time PCR. Residual infectivity of treated virus was tested by cell infection method as parallel control at the same time. The residual infectivity of virus decreased from 6.50 lgTCID50/mL to under the limit of detection as light intensity increased. Meanwhile, the quantity of virus cDNA decreased significantly (P < 0.05), which correlated to the decline of virus infectivity (R2 > 0.98). Methylene Blue with visible light could cause lesion to nucleic acid of Sindbis virus, the extent of which was light intensity-dependent and correlated to the decrease of virus infectivity. The results demonstrated that Real-Time PCR can be a useful tool for evaluating effect of virus inactivation after Methylene Blue treatment with light.

Cyclophosphamide-induced ovarian damage and stem cell factor expression in rat ovaries / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the possible pathways for ovarian injury after administration of cyclophosphamide in rats.</p><p><b>METHODS</b>Adult SD rats received a single injection of saline vehicle or chemotherapeutic agent cyclophosphamide, and 8 weeks later, the ovaries were removed, fixed and serially sectioned for pathological examination and ovarian follicle counting. The expression of stem cell factor (SCF) protein was evaluated by immunohistochemistry and immunoreactive score, and SCF mRNA expression determined by RT-PCR in rat ovaries.</p><p><b>RESULTS</b>Cyclophosphamide had a detrimental effect on ovarian stromal function and lead to primordial follicle loss. Immunoreactive SCF antigens were expressed on the oocytes in the primordial and primary follicles of rat ovaries, and also in the granulosa cells of the secondary follicles and early antral follicles. There was a higher granulosa SCF, lower oocyte SCF and higher SCF mRNA level in the ovaries of the rats exposed to cyclophosphamide as compared with those in control rat ovaries (P <0.05).</p><p><b>CONCLUSION</b>Altered SCF expression in the ovaries of rats exposed to cyclophosphamide can be helpful for understanding the mechanisms for chemotherapeutic drug-induced ovarian damage.</p>

Cyclophosphamide-induced rat ovarian damage and expression of gonadotropin-releasing hormone receptor in the damaged ovaries / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate ovarian follicular damage induced by chemotherapeutic agents and gonadotropin- releasing hormone receptor (GnRHR) expression in the damaged ovaries in rats.</p><p><b>METHODS</b>Two groups of adult SD rats were subjected to intraperitoneal injection of a single-dose cyclophosphamide and saline, respectively, and 8 weeks later, the ovaries were taken for observing the ovarian damages. The distribution of GnRHR was detected with immunohistochemistry, and RT-PCR was used to determine the expression of GnRHR mRNA in the rat ovaries.</p><p><b>RESULTS</b>Massive primordial follicular loss occurred in the ovaries of rats exposed to cyclophosphamide with also evident stromal ovarian blood vessel damages and focal fibrosis. Both the protein and mRNA expressions of GnRHR were detected in normal rat ovaries, but in rats exposed to cyclophosphamide, the expressions were significantly lowered in the ovaries (P<0.05).</p><p><b>CONCLUSION</b>Low-level GnRHR expressions in the ovaries of rats with cyclophosphamide exposure suggest microenvironment disturbances in the damaged rat ovaries in advanced stage of chemotherapy.</p>

Identification and characterization of mouse MTO1 gene related to mitochondrial tRNA modification.

The nucleotide modification in tRNA plays a pivotal role in the fidelity of translational process. The defects in nucleotide modification have often been observed in the mutated mitochondrial tRNAs associated with human diseases. Recently, MTO1-like protein in bacteria and yeast has been implicated to be a component of tRNA modification pathway. Here we report the identification and characterization of mouse MTO1 homolog. The mouse MTO1 gene containing 12 exons encodes a 669-residue protein with a strong homology to the MTO1-like proteins of bacteria and yeast, related to tRNA modification. Functional conservation of this protein is supported by the observation that the isolated mouse MTO1 cDNA can complement the respiratory-deficient phenotype of yeast mto1 cells carrying P(R)(454) mutation. MTO1 is ubiquitously expressed in various tissues, but with markedly elevated expression in tissues of high metabolic rates. Furthermore, we showed that mouse Mto1 localizes in mitochondrion. These observations suggest that the mouse MTO1 is a structural and functional homolog of yeast MTO1, thereby playing a role in the mitochondrial tRNA modification and protein synthesis.

46,XY female sex reversal patient with a novel point mutation in the coding sequence of the SRY gene / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the molecular mechanism of a Chinese patient with 46, XY sex reversal.</p><p><b>METHODS</b>DNA fragments of the SRY gene from the typical XY female sex reversal patient and her father were amplified by polymerase chain reaction (PCR). The amplified PCR fragments were cloned into the pUCm-T vector, and direct sequencing was carried out on an ABI 377-3 automated DNA sequencer to detect the mutation. PCR-restriction enzyme digestion was applied to detect the results of DNA sequencing.</p><p><b>RESULTS</b>A novel mutation of the SRY gene was identified in the XY sex reversal patient of this study. A T is replaced by an A in codon 129 at position +387, resulting in the replacement of the polar amino acid tyrosine (TAT) by the stop code (TAA) in the HMG-box, whereas her father was proved to have the wild-type sequence. Because the mutation introduced an enzyme site of MaeIII, the PCR-restrict enzyme digestion showed that there were three bands (131 bp,231 bp and 247 bp) in the patient, whereas two bands (131 bp and 478 bp) in normal man. It verified the results of sequencing analysis. The results after searching the Human Gene Mutation Database showed that this mutation was not described before and should be a new mutation.</p><p><b>CONCLUSION</b>The novel mutation in SRY gene has provided valuable information for the understanding of molecular mechanism of the patient with 46,XY female sex reversal.</p>

Effects of gonadotropin releasing hormone analogues on chemotherapy-induced ovarian function damage in rats / 中华妇产科杂志

Objective To investigate the effects of gonadotropin releasing hormone agonist (GnRH- a) and antagonist (GnRH-ant) on cyclophosphamide (CTX)-induced ovarian damage in rats.Methods Seventy-two Sprague-Dawley female rats were divided randomly into six groups,which received normal saline (NS),CTX,GnRH-a+NS,GnRH-a+CTX,GnRH-ant+NS,and GnRH-ant+CTX respectively.Levels of serum follicle-stimulating hormone (FSH),luteinizing hormone (LH) and estradiol (E_2) were measured successively by the enzyme-linked immunosorbent assay method,and half of the rats were killed in the first week and between the fourth and the fifth week after stop of medication,respectively to compare the weight of the ovaries and the number of the primordial follicles and the growth follicles.Results (1) Throughout experiment,the serum levels of FSH,LH and E_2 of the control group fluctuated slightly,while those in the CTX group kept rising.During medication treatment,compared with the control group[(118?16) ?g/L, (350?35) ?g/L] and the CTX group[(113?15) ?g/L,(289?42) ?g/L],the concentrations of LH [(42 ?8)-(47?7) ?g/L,(31?5)-(36?7) ?g/L] and FSH [(124?45)-(136?32)?g/L,(178 ?54)-(198+27)?g/L] in the GnRH-a groups and the GnRH-ant groups were maintained at low levels significantly and the levels of LH in the GnRH-ant groups were significantly lower than that in the GnRH-a groups,but the levels of FSH in the GnRH-ant groups were significantly higher than that in the GnRH-a groups(P0.05),but the levels of FSH,LH and E_2 of the GnRH-ant+CTX group rose obviously and were similar to the levels of the CTX group,especially the FSH,and the levels of LH and FSH of the GnRH- ant + CTX group [(156?12) ?g/L,(520?44) ?g/L] and the CTX group [(178?18) ?g/L,(546?36) ?g/L] were significantly higher than that of the other four groups [(121?15)-(132?13) ?g/L,(335 ?35)-(359?26) ?g/L] at the 4~(th)-5~(th) week after stop of treatment(P0.05),but the number of all kinds of follicles declined significantly in the GnRH-ant+CTX group[(195?15),(36?12)] and the CTX group [(212?11),(36?9)] compared to the other four groups[(302?15)-(690?43),(44?12)-(58?11),P

Evaluation of genome degradation of plasma hepatitis C virus during methylene blue photochemistry treatment / 中国输血杂志

Objective To study the degradation of hepatitis C virus(HCV) genome before and after methylene blue photochemistry(MB-P) treatment of the plasma.Methods MB was added to HCV positive plasma to a final concentration of 1.0?mol/L.The plasma was then exposed to 30000 Lux fluorescence.Plasma samples were then collected at different times of exposure.Real-time PCR was used to quantitatively study the course of the HCV-RNA degradation.The whole genome was screened for integrity by RT-PCR with 8 pairs of specific primers which targeted sequential overlapping sections of HCV genome.Results Results of real-time PCR showed that the copy number of HCV-RNA was continuously decreasing during MB-P treatment.RT-PCR results showed that the reactivity of different sections of the HCV genome to MB-P was significantly different and indicated that the 5' end and 3' end were more stable. Conclusion MB-P treatment could degrade HCV RNA with various sensitivities to different sections of the genome.RNA degradation may play an important role in plasma virus inactivation.Detection of HCV genomic RNA might be clinically useful to monitor the process and efficiency of virus inactivation.