Guhan Yangsheng Jing mitigates hippocampal neuronal pyroptotic injury and manifies learning and memory capabilities in sleep deprived mice via the NLRP3/Caspase1/GSDMD signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Guhan Yangsheng Jing (GHYSJ) is a traditional Chinese patent medicine, that has the function of nourishing the kidney and replenishing the essence, invigorating the brain and calming the mind. It is often used to treat dizziness, memory loss, sleep disorders, fatigue, and weakness, etc. However, its mechanism for improving sleep has not yet been determined.

AIM OF THE STUDY

This study aims to explore the effects of GHYSJ on Sleep Deprivation (SD)-induced hippocampal neuronal pyroptotic injury, learning and cognitive abilities, and sleep quality in mice.

METHODS

In this study, a PCPA-induced SD mouse model was established. We assessed the influence of GHYSJ on sleep quality and mood by using the pentobarbital-induced sleep test (PIST) and sucrose preference test (SPT). The pharmacological effects of GHYSJ on learning and memory impairment were evaluated by the Morris Water Maze (MWM) and Open Field Test (OFT). Pathological changes in the hippocampal tissue of the SD rats were observed via HE staining and Nissl staining. The severity of neuronal damage was evaluated by detecting the expression of the neuronal marker Microtubule-associated protein 2 (MAP2), via immunohistochemistry and immunofluorescence. Furthermore, the levels of neurotransmitter 5-hydroxytryptophan (5-HTP), 5-hydroxy tryptamine (5-HT), γ-aminobutyric acid (GABA), and Glutamic acid (Glu) in hippocampal tissues, as well as the expression of inflammatory factors Interleukin-1β (IL-1β) and Interleukin-18 (IL-18) in serum, were determined by ELISA. The expressions of mRNA and protein NOD-like receptor thermal protein domain associated protein 3 (NLRP3), Gasdermin D (GSDMD), Cysteinyl aspartate specific proteinase1 (Caspase1), High mobility group box-1 protein (HMGB1) and Apoptosis-associated speck-like protein containing CARD (ASC) related to the cellular ferroptosis pathway were tested and analyzed by RT-PCR and WB respectively.

RESULTS

PCPA significantly diminishes the sleep span of experimental animals by expediting the expenditure of 5-HT, consequently establishing an essentially direct SD model. The intervention of GHYSJ displays remarkable efficacy in mitigating insomnia symptoms, encompassing difficulties in initiating sleep and insufficient sleep duration. Likewise, it ameliorates memory function impairments induced by sleep deprivation, along with symptoms such as fatigue and depletion of vitality. GHYSJ exerts a protective influence on hippocampal neurons facilitated by inhibiting the down regulation of MAP2 and maintaining the equilibrium of neurotransmitters (5-HTP, 5-HT, GABA, and Glu). It diminishes the expression of intracellular pyroptosis-associated inflammatory factors (IL-1β and IL-18) and curbs the activation of the NLRP3/Caspase1/GSDMD pyroptosis-related signaling pathways, thereby alleviating the damage caused by hippocampal neuronal pyroptosis.

A review focusing on the role of pyroptosis in prostate cancer

As one of the types of programmed cell death, pyroptosis has become a focus of research in recent years. Numerous studies have shown that pyroptosis plays a regulatory role in tumor cell invasiveness, differentiation, proliferation, and metastasis. It has been demonstrated that pyroptosis is involved in the regulation of signaling pathways implicated in the pathogenesis of prostate cancer (PCa). Furthermore, the loss of expression of pyroptosis-related genes in PCa has been reported, and pyroptosis-related genes have demonstrated a considerable ability in predicting the prognosis of PCa. Therefore, the potential role of pyroptosis in regulating the development of PCa warrants further investigation and attention. In this review, we summarize the basics of the role of pyroptosis and also discuss research into the mechanisms of action associated with pyroptosis in PCa. It is hoped that by exploring the potential of the pyroptosis pathway in intervening in PCa, it will provide a viable direction for the diversification of PCa treatment.

Reliability of the Tibial Spine Versus ACL Stump in Assisting Tibial Tunnel Positioning During ACL Reconstruction: Analysis Based on 3-Dimensional Computed Tomography Modeling

Background

Several techniques have been used by surgeons for anatomic tibial tunnel placement in anterior cruciate ligament (ACL) reconstruction, including the ACL stump positioning (ASP) technique and the tibial spine positioning (TSP) technique.

Purpose/Hypothesis

The purpose of this study was to evaluate whether bony landmarks (medial and lateral tibial spine [MLTS]) can be a reliable reference for improving the accuracy of tibial tunnel placement in anatomic single-bundle ACL reconstruction compared with the ACL stump. It was hypothesized that the MLTS would not be a reliable bony landmark for tibial tunnel placement.

Study Design

Cohort study; Level of evidence, 3.

Methods

The 3-dimensional computed tomography images of 111 patients who underwent ACL reconstruction between 2020 and 2021 were included in this study. For tibial tunnel placement, the ASP technique was used in 49 patients, and the TSP technique was used in 62 patients. The 3-dimensional computed tomography images were reconstructed to enable measurements of the locations of the MLTS and tunnel center based on a grid method. Statistical analysis was conducted to compare the MLTS location and tibial tunnel position as well as the accuracy (mean distance of each actual location from the anatomic center) and precision (standard deviation of the accuracy, indicating the reproducibility of the tunnel position) of the tunnel position between the ASP and TSP groups.

Results

Significant differences were observed between the ASP and TSP groups in terms of the tibial tunnel position on the mediolateral axis (46.7% ± 2.0% vs 45.9% ± 2.2%, respectively; P = .034), while no significant differences were found in terms of the accuracy (4.1% vs 4.6%, respectively; P = .259) or precision (2.1% vs 2.1%, respectively; P = .259) of tibial tunnel positioning between the 2 groups.

Conclusion

In anatomic single-bundle ACL reconstruction, the use of the MLTS for tibial tunnel placement achieved comparable accuracy and precision compared with the use of ACL remnants, supporting its role as a reliable bony landmark in tibial tunnel positioning.

Icariin-Curcumol promotes docetaxel sensitivity in prostate cancer through modulation of the PI3K-Akt signaling pathway and the Warburg effect

BACKGROUND

Docetaxel (DTX) resistance reduces therapeutic efficacy in prostate cancer (PCa). Accumulating reports support the role of phytochemicals in the reversal of DTX resistance. This study aimed to determine whether Epimedium brevicornu and Curcuma zedoaria extracts (ECe), specially icariin-curcumol, attenuates DTX resistance and explore their potential mechanisms.

METHODS

Regulatory pathways were predicted between ECe active ingredients and PCa using network pharmacology. DTX-resistant cell LNCaP/R were established based on DTX-sensitive LNCaP, and xenograft models were further established. Active ingredients in ECe by HLPC-MS were identified. The binding of icariin and curcumol to the target was analyzed by molecular docking. Biochemical experiments were applied to determine the possible mechanisms by which Icariin-Curcumol regulates DTX sensitivity.

RESULTS

Akt1 and the PI3K-Akt signaling pathway were predicted as the primary functional target between drug and PCa. ECe and DTX inhibited xenograft tumor growth, inflammation, cell viability and promoted apoptosis. Icariin and curcumol were detected in ECe, and icariin and curcumol docked with Akt1. ECe, Icariin-Curcumol and DTX downregulated AR, PSA, PI3K, Akt1, mTOR, and HIF-1ɑ. Moreover, ECe, Icariin-Curcumol and DTX increased glucose and PDH, decreased lactic acid, ATP and LDH, and downregulated c-Myc, hnRNPs, VEGF, PFK1, and PKM2. Notably, the anti-PCa effect of DTX was attenuated compared to ECe or Icariin-Curcumol in the LNCaP/R model. The combined effect of Icariin-Curcumol and DTX was superior to that of DTX.

CONCLUSION

Our data support that Icariin-Curcumol reverses DTX resistance by inhibiting the PI3K-Akt signaling and the Warburg effect, providing new ideas for improving therapeutic measures for PCa.

A review focusing on the benefits of plant-derived polysaccharides for osteoarthritis

Osteoarthritis (OA) is a chronic joint disease characterized by progressive cartilage degeneration, which imposes a heavy physical and financial burden on the middle-aged and elderly population. As the pathogenesis of OA has not been fully elucidated, it is of great importance to develop targeted therapeutic or preventive medications. Traditional therapeutic drugs, such as non-steroidal anti-inflammatory drugs, steroids and opioids, have significant side effects, making the exploration for safe and effective alternative therapeutic drugs urgent. In recent years, many studies have reported the role of plant-derived polysaccharides in anti-inflammation, anti-oxidation, regulation of chondrocyte metabolism and proliferation, and cartilage protection, and have demonstrated their great potential in the treatment of OA. Therefore, by focusing on studies related to the intervention of plant-derived polysaccharides in OA, including in vivo and in vitro experiments, this review aimed to classify and summarize the existing research findings according to different mechanisms of action. In addition, reports on plant-derived polysaccharides as nanoparticles were also explored. Then, candidate monomers and theoretical bases were provided for the further development and application of novel drugs in the treatment of OA.

ACL stump and ACL femoral landmarks are equally reliable in ACL reconstruction for assisting ACL femoral tunnel positioning

PURPOSE

This study aimed to comparatively evaluate the accuracy of femoral tunnel positioning after anatomic single-bundle anterior cruciate ligament (ACL) reconstruction performed with the remnant preservation (RP) technique versus the non-remnant preservation (NRP) technique.

METHODS

A retrospective review of 145 patients who underwent ACL reconstruction from May 2020 to May 2022 were performed in this single-surgeon study. A total of 120 patients met the inclusion criteria and were allocated into two groups according to the surgical technique (i.e. RP group and NRP group). The relative location of the femoral tunnel in the lateral condyle was evaluated as a percentage using a standardized grid system on the three-dimensional computed tomography (3D-CT) image. The accuracy and precision of the RP group were assessed based on published anatomical data in direct comparison with the NRP group.

RESULTS

According to the surgical procedure, 57 of the 120 patients included were allocated into the RP group, and 63 into the NRP group. Significant differences were observed between the two groups in terms of tunnel position (posterior-to-distal (PD): 28.4 ± 5.4% (RP) vs. 31.8 ± 5.3% (NRP); P = 0.01), (anterior-to-posterior (AP): 32.6 ± 7.7% (RP) vs. 38.8 ± 7.7% (NRP); P = 0.00), while no significant differences were found in terms of the accuracy (8.6% (RP) vs. 8.9% (NRP); n.s) and precision (4.4% (RP) vs. 5.6% (NRP); n.s) of femoral tunnel positioning between the two groups.

CONCLUSIONS

From this single-surgeon study, it was concluded that there were no differences in the creation of ACL femoral tunnel between the RP technique and the non-remnant preserving technique. Meanwhile, the RP technique would not sacrifice the ideal position of the femoral tunnel and is able to retain the possible benefits of the ACL stump.

LEVEL OF EVIDENCE

Level III.

Validation of the TOLNet lidars during SCOOP (Southern California Ozone Observation Project)

Five TOLNet lidars participated to a validation campaign at the JPL-Table Mountain Facility, CA in August 2016. All lidars agreed within ±10% of each other and within ±7% of the ozonesondes. Centralized data processing was used to compare the uncertainty budgets. The results highlight the TOLNet potential to address science questions ranging from boundary layer processes to long range transport. TOLNet can now be seen as a robust network for use in field campaigns and long term monitoring.

Effect of high-fat diet on secreted milk transcriptome in midlactation mice

High-fat diet (HFD) during lactation alters milk composition and is associated with development of metabolic diseases in the offspring. We hypothesized that HFD affects milk microRNA (miRNA) and mRNA content, which potentially impact offspring development. Our objective was to determine the effect of maternal HFD on secreted milk transcriptome. To meet this objective, 4 wk old female ICR mice were divided into two treatments: control diet containing 10% kcal fat and HFD containing 60% kcal fat. After 4 wk on CD or HFD, mice were bred while continuously fed the same diets. On postnatal day 2 (P2), litters were normalized to 10 pups, and half the pups in each litter were cross-fostered between treatments. Milk was collected from dams on P10 and P12. Total RNA was isolated from milk fat fraction of P10 samples and used for mRNA-Seq and small RNA-Seq. P12 milk was used to determine macronutrient composition. After 4 wk of prepregnancy feeding HFD mice weighed significantly more than did the control mice. Lactose and fat concentration were significantly ( P < 0.05) higher in milk of HFD dams. Pup weight was significantly greater ( P < 0.05) in groups suckled by HFD vs. control dams. There were 25 miRNA and over 1,500 mRNA differentially expressed (DE) in milk of HFD vs. control dams. DE mRNA and target genes of DE miRNA enriched categories that were primarily related to multicellular organismal development. Maternal HFD impacts mRNA and miRNA content of milk, if bioactive nucleic acids are absorbed by neonate differences may affect development.

Porcine satellite cells are restricted to a phenotype resembling their muscle origin

Muscles in most domestic animals differ in function and growth potential based largely on muscle fiber type composition. Though much is known about satellite cells (SC), information is limited regarding how populations of SC differ with muscle fiber type, especially in pigs. Therefore, the objective of this study was to isolate and culture SC from red (RST) and white (WST) portions of the semitendinosus muscle of neonatal and adult pigs and determine their capacity to proliferate, differentiate, and express various myosin heavy chain (MyHC) isoforms in vitro. Porcine satellite cells were isolated from RST and WST muscles of 6-wk-old and adult (>6-mo-old) pigs and cultured under standard conditions. Muscle from neonatal pigs yielded nearly 10 times more (P < 0.001) presumptive satellite cells as those from adult pigs, with fusion percentages close to 60% for the former. The RST yielded more (P < 0.001) SC per gram muscle compared to WST, 8.1 ± 0.2 × 10(4) cells versus 6.7 ± 0.1 × 10(4) cells/gram muscle in young pigs, and 9.7 ± 0.4 × 10(3) cells versus 5.5 ± 0.4 × 10(3) cells/gram muscle in adult pigs, respectively. Likewise, satellite cells from RST proliferated faster (P < 0.001) than those from WST across both ages, as indicated by a shorter cell doubling time, 18.6 ± 0.8 h versus 21.3 ± 0.9 h in young pigs, and 23.2 ± 0.7 h versus 26.7 ± 0.9 h in adult pigs, respectively. As a result of shorter times to confluence, satellite cells from RST also formed myotubes earlier than those SC originating from WST. Once induced, however, SC from WST differentiated and fused faster (P < 0.05) as evidenced by fusion percentage within the first 24 h, 41.6% versus 34.3%, respectively; but reached similar ultimate fusion percentages similar to WST by 48 h. Over 90% of MyHC expressed in maximally fused SC cultures from both RST and WST was restricted to the embryonic isoform. Type IIX MyHC mRNA was not detected in any culture. Myotube cultures from RST expressed more (P < 0.01) Type I MyHC isoform mRNA than those from WST, whereas those cultures from WST expressed more (P < 0.05) Type II (including Types IIA and IIB) MyHC transcripts. These data show SC cultures from porcine fast and slow muscles express MyHC profiles largely reflective of their muscle of origin and suggest satellite cells are partially restricted to a particular muscle phenotype in which they are juxtapositioned. Understanding the molecular nature of these intrinsic control mechanisms may lead to improved strategies for augmenting meat animal growth or muscle regeneration.

Meat Science and Muscle Biology Symposium: stem cell niche and postnatal muscle growth

Stem cell niche plays a critical role in regulating the behavior and function of adult stem cells that underlie tissue growth, maintenance, and regeneration. In the skeletal muscle, stem cells, called satellite cells, contribute to postnatal muscle growth and hypertrophy, and thus, meat production in agricultural animals. Satellite cells are located adjacent to mature muscle fibers underneath a sheath of basal lamina. Microenvironmental signals from extracellular matrix mediated by the basal lamina and from the host myofiber both impinge on satellite cells to regulate their activity. Furthermore, several types of muscle interstitial cells, including intramuscular preadipocytes and connective tissue fibroblasts, have recently been shown to interact with satellite cells and actively regulate the growth and regeneration of postnatal skeletal muscles. From this regard, interstitial adipogenic cells are not only important for marbling and meat quality, but also represent an additional cellular component of the satellite cell niche. At the molecular level, these interstitial cells may interact with satellite cells through cell surface ligands, such as delta-like 1 homolog (Dlk1) protein whose overexpression is thought to be responsible for muscle hypertrophy in callipyge sheep. In fact, extracellular Dlk1 protein has been shown to promote the myogenic differentiation of satellite cells. Understanding the cellular and molecular mechanisms within the stem cell niche that regulate satellite cell differentiation and maintain muscle homeostasis may lead to promising approaches to optimizing muscle growth and composition, thus improving meat production and quality.

An Intelligent Bone Spinal Disc Implant for Asian Population

There is a high level of patient appeal and physician acceptance of motion preservation as the future treatment of symptomatic and painful degenerative disc disease. However, spinal artificial disc replacement is still in its infancy. We have been designing, developing and evaluating motor articulated implants for use in bone-spinal disc surgery for Asian population. Apart from the generally smaller built of Asian compared to the American and European, the motor articulated implant should make provisions for the difference in eastern and western lifestyles. In the eastern world, we generally sit on a lower platform. Frequent activities like squatting result in a different stress-strain profile on the lower spine of an Asian compared to that of the Westerner. Preserving the motion of flexion bending in human lumbar spine is important. The motion preservation characteristics have to be maintained without compromising device durability, bone-device interfaces and corrective intervention. A systematic approach was adapted in designing the implant. Physical size of the implant should replicate the actual Intravertebral Disc (IVD). Implant should be able to fit into vertebral body. This is aid by shaping the spine vertebral body to accommodate the implant. A motor articulated implant must have suitable spaces for the implementation of sensors to detect forces and motors to control the motion of the prototype. The device must be able to receive real-time sensory inputs which can then modulate the implant orientation in bending accordingly. A prototype of the implant device has been fabricated to study its motion preservation capabilities. The prototype comprises of a parallel manipulator mechanism where the top plate is linked to the base plate by independent kinematic chains. The mechanical structure is made of Aluminium 6061. The mechanical parts were also put through the chemical process of anodizing for a good finishing surface. In the prototype device, we used three DC micromotors (Faulhaber) for actuation. Due to the small dimension, fibre optics pressure sensors were used. Three customized sensors were developed, calibrated and deployed on the upper plate. A PIC32 microprocessor was used to compute the compliance motion of the prototype when subjected to forces during flexion bending motion. The computer simulation of the kinematics of the parallel mechanism demonstrated the implant's flexion bending capabilities. We are conducting biomechanical experiments with this prototype implant deployed between L3–L5 of an artificial spinal column. The prototype device should achieve motion preservation capabilities comparable to the existing implants. More computer simulation will also be conducted to improve the mechanical design and control mechanisms of the proposed disc implant.

The molecular regulation of muscle stem cell function

Muscle satellite cells are responsible for the postnatal growth and robust regeneration capacity of adult skeletal muscle. A subset of satellite cells purified from adult skeletal muscle is capable of repopulating the satellite cell pool, suggesting that it has direct therapeutic potential for treating degenerative muscle disease. Satellite cells uniformly express the transcription factor Pax7, and Pax7 is required for satellite cell viability and to give rise to myogenic precursors that express the basic helix-loop-helic (bHLH) transcription factors Myf5 and MyoD. Pax7 activates expression of target genes such as Myf5 and MyoD through recruitment of the Wdr5/Ash2L/MLL2 histone methyltransferase complex. Extensive genetic analysis has revealed that Myf5 and MyoD are required for myogenic determination, whereas myogenin and MRF4 have roles in terminal differentiation. Using a Myf5-Cre knockin allele and an R26R-YFP Cre reporter, we observed that in vivo about 10% of satellite cells only express Pax7 and have never expressed Myf5. Moreover, we found that Pax7(+)/Myf5(-) satellite cells give rise to Pax7(+)/Myf5(+) satellite cells through basal-apical asymmetric cell divisions. Therefore, satellite cells in skeletal muscle are a heterogeneous population composed of satellite stem cells (Pax7(+)/Myf5(-)) and satellite myogenic cells (Pax7(+)/Myf5(+)). Evidence is accumulating that indicates that satellite stem cells represent a true stem cell reservoir, and targeting mechanisms that regulate their function represents an important therapeutic strategy for the treatment of neuromuscular disease.

[A clinical analysis of 102 cases of chronic n-hexane intoxication]

OBJECTIVE

Chronic n-hexane exposure can result in n-hexane intoxication which is mainly characterized by a series of manifestations of peripheral nerve lesions. The disease was sometimes misdiagnosed as "unknown multiple peripheral neuropathy". 102 cases of n-hexane intoxication were investigated and reported in order to call attention to the disease.

METHODS

All the 102 cases, male 30, female 72; age 17 - 29, mean (21 +/- 3) were n-hexane workers. During the hospitalization the following data were collected: medical history, neurological check up, electromyogram, electrocardiogram, serum biochemical analysis, ophthalmologic study and the metabolite of n-hexane- the urinary 2, 5-hexanedione level. The airborne n-hexane levels of the working environment were also measured.

RESULTS

The average incubation period of the 102 cases was (8.3 +/- 2.6) months. The average course of the disease was (12.1 +/- 4.2) months. Airborne n-hexane concentration of the working places ranged from 188.0 to 7,848.6 mg/m(3). The most common prodromes were headache, anorexia, dizziness and weight loss. The main clinical manifestations of the disease were ascending abnormal sensation. Sensory loss and dyskinesia began from the distant parts of the limbs. The patient had reduction or disappearance of tendon reflexes, weakness and muscle atrophy in the limbs. Electromyography showed a neuropathic pattern, which was parallel to the clinical symptoms and signs. Delayed worsening of symptoms and signs after cessation of n-hexane exposure was observed in some cases. All the 102 cases recovered totally after treatment with Vitamin B, Chinese traditional medicine, physical therapy and training.

CONCLUSION

The main lesion of the disease is multiple peripheral neuropathy. Diagnosis should be made according to the history of n-hexane exposure, the typical clinical manifestations of peripheral neuropathy as well as the neuropathic changes on electromyography. Therapeutic measures for peripheral neuropathy of other etiologies may be used and the prognosis is optimistic if correct diagnosis is made and further exposure stopped.

Laser ablation reveals regulation of ciliary activity by serotonergic neurons in molluscan embryos

Early in embryonic development, the pond snail Helisoma trivolvis exhibits a rotational behavior that is generated by beating of cilia in the dorsolateral and pedal bands. Although previous anatomical and pharmacological studies provided indirect evidence that a pair of serotonergic neurons, Embryonic Neurons C1 (ENC1s), is involved in regulating embryonic rotation, direct evidence linking ENC1 to ciliary function is still lacking. In the present study, we used laser microbeams to perturb ENC1 in vivo while monitoring ciliary activity in identified ciliary bands. A laser treatment protocol to specifically ablate ENC1 without damaging the surrounding cells was established. Unilateral laser treatment of ENC1 caused transient increases in the activity of the pedal and ipsidorsolateral cilia, lasting 30-50 min. In contrast, activity of cilia that were not anatomically associated with ENC1 was unaffected by laser treatment. Mianserin, an effective serotonin antagonist in Helisoma ciliated cells, decreased the overall CBF of pedal and dorsolateral cilia by reducing the occurrence of spontaneous CBF surges in these cilia. Finally, the cilioexcitatory action of ENC1 laser treatment was mimicked by serotonin and reduced in the presence of mianserin. These results suggest that laser treatment provokes a release of serotonin from ENC1, resulting in a prolonged elevation of activity in the target ciliary cells. We conclude that, in addition to their previously established role in regulating neurodevelopment, ENC1s also function as serotonergic motor neurons to regulate ciliary activity, and therefore the rotational behavior of early embryos.

[Study on clinical and molecular biological characteristics of infant acute leukemia]

OBJECTIVE

To study the clinical and molecular biological characteristics of infant acute leukemia (IAL).

METHODS

R and/or G banding technique was used for analysis of karyotype. DNA blotting for HRX gene rearrangement, and polymerase chain reaction (PCR) and reverse transcriptase PCR (RT-PCR) for fusion gene detection.

RESULTS

Twenty cases of IAL were detected. HRX gene rearrangement was found in 10 cases, including HRX/AF-4 fusion gene in 5, HRX/AF-9 fusion in 2, and HRX/ENL fusion in 1, HRX self-fusion mediated by alu-repeat homologous recombination and HRX/EEN fusion each in one (HRX/EEN is a novel fusion gene reported for the first time).

CONCLUSION

High frequency of HRX gene rearrangement occurred in IAL, which is characterised by a massive leukemia cell burden and 11q23 translocation, forming fusion genes, especially HRX/AF-4 (about 50%). The results are of important significance in guiding clinical treatment and approaching the etiology of IAL.

[Hepatitis B virus infection and aflatoxin exposure in the development of primary liver cancer]

OBJECTIVE

To investigate the role of hepatitis B Virus (HBV) infection and aflatoxin (AF) exposure in the development of primary liver cancer (PLC).

METHODS

A 10-year prospective case-control study was carried out in 737 HBsAg carriers and 699 HBsAg negative cases, and the aflatoxin B1 albumin adducts (AFB1-Alb) were detected in the serum of the cohort including 30 HBsAg postive cases and 150 control individuals according to the case-control study model (ratio 1:5) at random in the high prevalance area of PLC.

RESULTS

The average year-incidence rate was significantly higher in the HBsAg postive group (824.13/100,000) than in the control group (70.97/100,000, RR = 11.61). There was no significant difference in the incidence rate of other tumors between the two groups (P > 0.05). The serum positive rate of AFB1-Alb was significantly higher in the PLC group (76.67%) than in the control group (48.67%, OR = 3.47), and the serum concentration of AFB1-Alb was also significantly higher in the PLC group than in the control group (P < 0.01).

CONCLUSION

HBV infection and AF exposure are important etiological factors in the development of PLC and both result in carcinogenic synergy.

[Fluorescence-based semi-automated gene scan with microsatellite markers by multiplex PCR techniques]

OBJECTIVE

To develop a high output and low cost multiplex PCR approach to facilitating large scale gene scan and gene typing with microsatellite markers.

METHODS

5-15 pairs of primers of microsatellite loci were added in one single tube with 5ul reaction volume, containing 10 mmol/L Tris-HCl (pH8.3), 50 mmol/L KCl,0. 1mg/ml gelatin, 3.0 mmol/L MgCl2, 200micromol/L dNTPs (each), 0.25U Taq DNA polymerase, Taq Start antibody and DNA templates. PCR thermocycles were carried out on Perkin Elmer Gene Amp PCR System 9600 with touch-down algorithm (the annealing temperature was decreased by 0.5 C in each cycle) to meet the different demands of different primers.

RESULTS

Up to 10-15 loci were labeled by different fluorescents or by the same fluorescent, but their PCR amplification fragments did not overlap in size. Almost all target microsatellite loci were successfully co-amplified in a 5 microliter reaction volume,electrophoresized and analyzed in a single gel lane with Perkin Elmer ABI 373A DNA sequencer, and 9 microsatellite loci were well genotyped.

CONCLUSION

This high output and low cost genotyping protocol is applicable to gene mapping, human evolution and forensic analysis.

[Study of dominant negative effect of the PLZF-RARalpha against the wild-type RARalpha in acute promyelocytic leukemia]

OBJECTIVE

To explore the role of promyelocytic leukemia zinc finger (PLZF) gene on 11q23 and RARalpha gene on 17q21.

METHODS

Eight PLZF/RARalpha expression plasmids with deletions of different PLZF motifs were constructed by using PCR based-method.

RESULTS AND CONCLUSION

By transient co-transfection, it was confirmed that PLZF/RARalpha had a dominant negative effect against the wild-type RARalpha, the POZ domain of PLZF/RARalpha was responsible for the dominant negative effect and the PLZF/RARalpha may play certain role through a spatial interaction with POZ.

[Immunoglobulin super-gene family and its related genes in detecting MRD in ALL]

OBJECTIVE

To study the rearrangements of the immunoglobulin super-gene family and its related genes, as well as their application in the detection of minimal residual disease (MRD) in acute lymphoblastic leukemia (ALL).

METHODS

15 ALL cases including 11 B-ALLs and 3 T-ALLs were studied separately by using immunophenotype detection and molecular clonging methods.

RESULTS

Using DNA Southern blot analysis, we found that the rearrangement of IgH gene existed in 11 B-lineage ALL cases. The specific PCR band was visualized through amplification of the CDR3 region and J region of IgH gene. Furthermore, we sequenced the V-D-J junctional region of IgH gene in 3 B-lineage patients and synthesized two probes against the V-D-J junctional region in order to detect MRD. The hybridization results showing the sensitive of the two probes were 10(-4). In addition, we performed comparative study of MRD detection by using both T cell receptor (TCR) gamma gene as gene specific marker and SIL-TAL-1 fusion gene as tumor-specific marker in one T-ALL patient.

CONCLUSION

The rearrangements of IgH gene, as well as TCR gene and tumor fusion gene can be used as specific markers in the detection of MRD in ALL.

Long-term follow-up of minimal residual disease in childhood acute lymphoblastic leukemia patients by polymerase chain reaction analysis of multiple clone-specific or malignancy-specific gene markers

Two types of markers, namely the clone-specific markers including T-cell receptor (TCR) gamma, TCR delta, and Ig heavy-chain (IgH) gene rearrangements, and malignancy-specific fusion gene mRNA such as SIL-TAL-1, BCR-ABL, and HRX-partner genes, were investigated by molecular biology techniques in 65 Chinese patients with acute lymphoblastic leukemia (ALL). In combination, these markers were informative among 96% of patients. Minimal residual disease (MRD) was followed up in 23 of these patients with available materials over a period varying from 8 to 54 months with at least one leukemia-specific probe. In most children, MRD was decreased continuously to an ultimately undetectable level within 6 to 12 months after remission induction therapy. One patient exhibited low-level residual leukemic cells for 4 years before the MRD turned negative. Another patient remained in complete remission for 45 months, although a positive signal was detected at 34 months using TCR delta probe, but was negative with a TCR gamma marker which was positive at presentation. In three patients who relapsed, MRD either persisted through the clinical course or became positive and eventually increased 3-11 months before clinical relapse. These data suggested that the combined use of multiple gene markers is a valuable tool for the PCR-based MRD detection, since it can cover most ALL patients. Furthermore, long-term follow-up of MRD is helpful for determining the dosage as well as the period of maintenance chemotherapy and for predicting impending relapse.

[Junctional sequences of T cell receptor V delta 2-D delta 3 or D delta 2-D delta 3 rearrangements in acute lymphoblastic leukemia]

T-cell receptor (TCR) delta chain gene rearrangements were studied by polymerase chain reaction (PCR) analysis in 46 patients with acute lymphoblastic leukemia (ALL). Sixteen patients were found to have incomplete rearrangements of the TCR delta genes. Among them, 13 patients displayed V delta 2-D delta 3 rearrangement, while 3 had both V delta 2-D delta 3 and D delta 2-D delta 3 rearrangements. To determine the junctional sequence of TCR delta gene, PCR products from the 16 patients were sequenced directly or after M13 cloning. The results showed the junctional sequences of TCR delta gene are highly specific for each allele. This sequence diversity resulted from several factors including deletion of the 3' end of V delta 2 or D delta 2 segment and 5' end of D delta 3 segment, the presence of D delta 1 or D delta 2 sequences, insertion of N nucleotides and the association of P nucleotides with intact V delta 2 and D delta 3 segments. In addition, analysis of N-nucleotide contents revealed that the amount of GC was much larger than that of AT (70%: 30%), indicating the insertion of N nucleotide was not fully random. Our sequence data confirmed that the imcomplete rearrangement of TCR delta gene is an early event in the lymphoid cell ontogenesis, and its N sequences in V-(D)-J junctional region may be used as a specific marker of clonality to detect the minimal residual disease (MRD) in ALL.