Fully Automatic Fine-Grained Grading of Lumbar Intervertebral Disc Degeneration Using Regional Feature Recalibration Network.

Accurate fine-grained grading of lumbar intervertebral disc (LIVD) degeneration is essential for the diagnosis and treatment design of high-incidence low back pain. However, the grading accuracy is still challenged by lacking the fine-grained degenerative details, which is mainly due to the existing grading methods are easily dominated by the salient nucleus pulposus regions in LIVD, overlooking the inconspicuous degeneration changes of the surrounding structures. In this study, a novel regional feature recalibration network (RFRecNet) is proposed to achieve accurate and reliable LIVD degeneration grading. Detection transformer (DETR) is first utilized to detect all LIVDs and then input to the proposed RFRecNet for the fine-grained grading. To obtain sufficient features from both the salient nucleus pulposus and the surrounding regions, a regional cube-based feature boosting and suppression (RC-FBS) module is designed to adaptively recalibrate the feature extraction and utilization from the various regions in LIVD, and a feature diversification (FD) module is proposed to capture the complementary semantic information from the multi-scale features for the comprehensive fine-grained degeneration grading. Extensive experiments were conducted on a clinically collected dataset, which consists of 500 MR scans with a total of 10225 LIVDs. An average grading accuracy of 90.5%, specificity of 97.5%, sensitivity of 90.8%, and Cohen's kappa correlation coefficient of 0.876 are obtained, which indicate that the proposed framework is promising to provide doctors with reliable and consistent fine-grained quantitative evaluation results of the LIVD degeneration conditions for the optimal surgical plan design.

Child inflammatory myofibroblastic tumor of the kidney misdiagnosed as Wilms' tumor: case report.

Inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal tumor with recurrent potential, most commonly occurring in the lung but rarely in the kidney with nonspecific clinical symptoms and radiographic features, thus may be misdiagnosed as primary malignant lesions. We described a 6-year-old boy with renal IMT misdiagnosed as Wilms' tumor and then treated with right nephrectomy. It should be emphasized that in addition to the most common renal tumors in children, IMT should also be taken as a differential diagnosis. It is therefore mandatory to carry out clinical interpretation, careful histologic examination, and immunohistochemical studies collectively to make solid diagnosis.

Asymptomatic adult Wilms' tumor: A case report.

Wilms' tumor, also called nephroblastoma, is an extremely uncommon kidney tumor of adulthood. We reported a adult man with a left kidney mass diagnosed as Wilms' tumor. Case presentation: A 25-year-old man was hospitalized due to injury of the anterior cruciate ligament of the right knee. Preoperative imaging accidentally revealed a mass measuring 53 × 46 mm involving the middle and lower segments of the left kidney without evidence supporting the invasion of the surrounding structures or metastasis. The patient didn't show any symptom commonly occurred in Wilms' tumor, such as flank pain or hematuria. After nephrectomy, the diagnosis of adult Wilms' tumor was confirmed based on the tumor morphology and immunohistochemical findings. Conclusion: In adult patients without any clinical manifestations or favorable imaging findings for low-stage renal cell carcinoma, the diagnosis of Wilms' tumor should be taken into consideration.

Computed Tomography and Magnetic Resonance Imaging Appearances of Abdomen and Pelvis Gossypibomas at the Varied Durations After Cesarean Section.

The incidence of gossypiboma is considerably higher in open cavity surgeries, among which cesarean section ranks number one. However, it is difficult to diagnose abdomen or pelvic gossypibomas after cesarean section. We retrospectively analyzed the clinical and imaging data of three pathologically confirmed gossypiboma patients at varied durations after cesarean section. In case one, at four months after cesarean section, a gossypiboma near the small intestine caused fistula and intestinal obstruction. Soft tissue density lesion along the intestinal canal made the "segmental honeycomb sign" and "truncation" with metal markings on the edge on computed tomography (CT). Magnetic sensitivity artifacts were demonstrated as hypointensity on T1 weighted image (T1WI) and T2 weighted image (T2WI), while hyperintensity was seen on the diffusion weighted image (DWI). In case two, a gossypiboma in the peritoneal and intestinal space was revealed with MRI at 18 months after cesarean section. It was featured as a cystic and solid lesion, with "vortex like sign" and obvious ring enhancement on contrast-enhanced MRI scan. In case three, five years after cesarean section, a mass was palpated in the right middle and lower abdomen. MRI revealed a round mass of T1 hypointensity with mixed T2 signal, as well as swirling hypointensity in T2WI, T2WI-fat suppression (FS), and DWI. In CT and MRI examinations for suspected gossypiboma after cesarean section, "honeycomb sign" and "vortex like sign" are the characteristic appearances; gauze translocated into the intestine may show the "truncation sign". Accurate diagnosis is based on the surgery history, symptoms, and imaging features.

On the System of High Order Rational Difference Equations.

This paper is concerned with the boundedness, persistence, and global asymptotic behavior of positive solution for a system of two rational difference equations x n+1 = A + (x n /∑ i=1 (k) y n-i ), y n+1 = B + (y n /∑ i=1 (k) x n-i ), n = 0,1,…, k ∈ {1,2,…}, where A, B ∈ (0, ∞), x -i ∈ (0, ∞), and y -i ∈ (0, ∞), i = 0,1, 2,…, k.

Detection of a novel large deletion causing α-thalassemia in South China.

α-Thalassemia is an inherited autosomal recessive disorder. It is one of the most common monogenic abnormalities known in the world and is prevalent in tropical and subtropical regions. α-Thalassemia is more frequently caused by deletional type than non-deletional type. Recently, we identified a novel large deletional type of α-thalassemia named --(FZ)/αα from a family in South China. Multiplex ligation-dependent probe amplification was used for diagnosing the carrier and prenatal diagnosing for a fetus. Real-time PCR was employed for characterizing the deletion breakpoints and the deletional segment was determined as 300 kb in length extending from the telomere to AXIN1 gene on the short arm of chromosome 16. The carriers in the family members were detected by real-time PCR using designed primers.

[Carrier diagnosis of F9 gross deletion by multiple ligation-dependent probe amplification in hemophilia B].

OBJECTIVE: To investigate the application of multiplex ligation-dependent probe amplification (MLPA) in the gene diagnosis of hemophilia B (HB). METHODS: MLPA and linkage analysis of short tandem repeat (STR) were used for gene diagnoses of two HB families with gross deletions of F9 gene, which were negative by sequencing. RESULTS: The MLPA results indicated the loss of one or two exons in the two patients with the ratio lower than 0.10. Their mothers showed a ratio average of 0.50 ± 0.05 for the corresponding probes, which revealed she was carrier of large deletions of the F9 gene. The ratios of three sisters of the HB patients were normal, which indicated they were non-carriers. Linkage analysis was consistent with MLPA, but sequencing was not conclusive. CONCLUSION: This report illustrated that MLPA technique represented an efficient method to screen F9 gene gross deletions in sequencing undiagnosed carriers of hemophilia B.

[Detection of common deletions and mutations causing α-thalassemia in Southeast Asians and Southern Chinese with denaturing high performance liquid chromatography].

OBJECTIVE: To establish a comprehensive and simple assay using denaturing high performance liquid chromatography (DHPLC) for the diagnosis of most common mutations and deletions of α-thalassemia gene in Southeast Asians and Southern Chinese. METHODS: This assay has included a duplex polymerase chain reaction (PCR) followed by DHPLC analysis. An improved PCR was also performed followed by DHPLC analysis. With this assay, a blinded study of 160 samples was screened for three common mutations and three common deletions. RESULTS: The duplex PCR-DHPLC combined with the improved PCR-DHPLC analysis has detected all mutations and the wild-type allele. The results were consistent with those by the original methods. CONCLUSION: This molecular assay may be used for the diagnosis of α-thalassemia patients from this geographical region. The method is accurate, rapid, semi-automatic and cost-effective, which makes it suitable for large-scale screening.

Detection of α-globin gene deletions using denaturing high-performance liquid chromatography and multiplex ligation-dependent probe amplification.

BACKGROUND: Multiplex ligation-dependent probe amplification (MLPA) has been used to detect deletions and mutations of the α-globin gene for diagnosis of α-thalassemia. MLPA reaction products are usually separated and analyzed by high-voltage capillary gel electrophoresis (CGE). The goal of this study was to find and use a cost-effective method to separate and analyze MLPA products. METHODS: Blood samples were collected from China. DNA was extracted and amplified by PCR using fluorescently labeled primers. In this study, denaturing high-performance liquid chromatography (DHPLC) was used to separate and analyze the reaction products. And the optimal separation conditions were determined using nondenaturing columntemperature. RESULTS: The DHPLC conditions were optimized and have been applied to separate MLPA products and 27 of the MLPA products from 50 to 320 bp were well separated. DHPLC was able to separate up to 37 reaction products that differed by 4-12 base pairs and detected target gene deletions by differences in peak size. Compared with CGE, both the specificity and sensitivity of DHPLC for the 107 DNA samples were 100%. CONCLUSIONS: DHPLC could be used to test routinely for α-globin gene mutations and deletions. Combined with MLPA, DHPLC is a low-cost, simple to use, accurate technique with practical value.

A rapid detection for α-thalassemia by PCR combined with dissociation curve analysis.

Deletion mutations of 3.7 kb and 4.2 kb of α-globin gene are the most common causes of α-thalassemia (-α(3.7)/, -α(4.2)/). A simple, rapid assay by using a single-tube PCR to detect the two deletions has been needed. In this study, a pair of shared primers was designed for α2 and α1 gene but with length-different amplicons (159 bp and 409 bp). On the dissociation curve analysis profile after PCR, there shows two obvious peaks which represent the two different amplicons. Relative copy number of α2 and α1 gene can be deduced from the ratio of the two peaks. A comprehensive diagnosis for α-thalassemia 10 genotypes of deletions can be achieved when combined with a single-tube duplex PCR for detecting --SEA and non-deletional alleles of αα or α(T)α. Besides, a single-tube multiplex PCR, which is a cost-effective version of dual-priming-oligonucleotide based system, was designed for two common mutations of α-thalassemia in China (Hb Constant Spring and Hb Quong Sze), and these two mutations can be identified in samples by use of dissociation curve analysis. In all, using above three PCRs followed by dissociation curve analysis, three deletions and two mutations of α-thalassemia in the populations of southern China and Southeast Asia can be detected for molecular diagnosis or prenatal diagnosis. A blinded study of 163 samples was performed using this new assay and it was concordant with the original methods. This comprehensive molecular assay is simple, rapid, automatic and cost-effective, and can be used to diagnose α-thalassemia in this geographical area.

An assay of gene copy number and its application based on heteroduplex products.

The aim of this study was to set up a simple and efficient method for detecting gene copy number, based on heteroduplex products from single-tube PCR/DHPLC. Single-nucleotide polymorphisms (SNPs) on the α-globin gene and chromosome 21 were used as examples. And the formula for quantitative calculation of gene copy number was deduced-based on the peak heights of homoduplexes and heteroduplexes on the DHPLC pattern. 27 samples (14 normal DNA and 13 cases of trisomy-21) were assessed with this method, and 160 samples (48 normal DNA and 112 α-thalassemia samples) were assessed with this method combined with a duplex PCR/DHPLC. Results for 184 of 187 cases were concordant with the known genotypes; three cases of trisomy-21 could not be detected because the target SNPs were homozygous. In conclusion, quantitative assessment of heteroduplex products from single-tube PCR/DHPLC is simple and rapid, and can be used to detect α-thalassemia gene deletions (α(-3.7), α(-4.2)) and trisomy-21.

[Application of multiplex ligation-dependent probe amplification to diagnosis and prenatal diagnosis of common aneuploidies].

OBJECTIVE: To investigate the application value of the multiplex ligation-dependent probe amplification (MLPA) technique in diagnosis and prenatal diagnosis of chromosomes 13, 18, 21, X and Y aneuploidy. METHODS: Forty-four cases including 30 peripheral blood samples, 10 fetal cord blood samples, and 4 amniotic fluid samples were collected in this study. DNA was isolated from the samples and detected by MLPA, followed by analyzing in ABI310 Genetic Analyzer. Analysis of copy number changes for chromosomes 13, 18, 21, X and Y was carried out with RH-MLPA-analysis software. The routine karyotype analyses were also done for all the samples. RESULTS: Of 44 samples, the results of 42 by MLPA method was consistent with that by chromosome karyotyping. Only one case with trisomy 21 chimerism was failed to reach conclusion. In addition, one case of mark chromosome segment was identified as Y-chromosome segment by MLPA, while karyotyping failed to make judgment. The accurate rate of MLPA was 97.7% (43/44). CONCLUSION: The MLPA technique can simultaneously detect dozens of different target sequences and their copy number changes in a single reaction. It showed high specificity, good reproducibility, was fast and high-throughput. The MLPA technique can be applied to diagnosis and prenatal diagnosis of the common chromosomal aneuploidy.

[Improvement and application of DXS52(St14) in gene diagnosis of hemophilia A].

OBJECTIVE: To improve the experimental method of DXS52 (St14) and apply it to genetic testing for hemophilia A (HA). METHODS: PCR of DXS52 and agarose gel electrophoresis were performed for genetic testing in 61 non-inversion HA families. Linkage analysis of 7 loci within the FVIII gene including Bcl I, Hind III, Xba I, STR1, STR13, STR22 and STR24 were also carried out for the 61 families. RESULTS: DXS52 can provide information in 43 out of 61 families and the diagnostic rate was 70.5%. Eight families can be diagnosed only by DXS52 locus, accounting for 13.1%. Two families were found to have recombination between DXS52 and FVIII. CONCLUSION: The new experimental conditions can reach accurate and clear results in DXS52 genetic testing. This gene maker has high diagnostic rate, so it is an indispensable linkage analysis method in HA gene diagnosis. More caution should be paid when using the extragenic locus DXS52 to perform gene diagnosis because of its high recombinant rate with FVIII.

Identification of seven novel mutations in the factor VIII gene in 18 unrelated Chinese patients with hemophilia A.

BACKGROUND: Hemophilia A (HA) is an X-linked inherited bleeding disorder caused by decreased activity of factor VIII (FVIII) due to heterogenous mutations in the FVIII coding gene (F8). The type of mutation plays an important role in the FVIII inhibitor formation. To date, several studies on the spectra of F8 defects have been performed in Western populations, but similar studies in Asian races are scarce. Here, we reported the distribution of the F8 gene mutations in 18 unrelated Chinese patients with HA. METHODS: Intron 22 and intron 1 inversions in the F8 gene were screened in 158 unrelated patients with HA using a long-distance PCR and multiplex PCR method. Direct sequencing of the coding region of the F8 gene was used to identify the mutations responsible for HA in 18 unrelated Chinese HA patients who were negative for intron 22 and intron 1 inversions; sequences were compared with the HAMSTeRS database. A clotting method was used to assay the FVIII activity level and the Bethesda assay was used to detect the FVIII inhibitor. RESULTS: A total of 18 different HA F8 mutations were identified, seven of which were described for the first time. These novel mutations included five small deletions, one point mutation and one small insertion. One novel mutation (4382-3 AC deletion) was associated with inhibitor development. CONCLUSION: These data extend our insight into the mechanisms by which novel amino acid mutations may lead to HA and how the HA patient genotypes influence the risk of FVIII inhibitor.

Novel technique for rapid detection of alpha-globin gene mutations and deletions.

Populations in Southeast Asia and South China have high frequencies of alpha-thalassemia caused by alpha-globin gene mutations and/or deletions. This study was designed to find an efficient and simple diagnostic test for the mutations and deletions. A duplex polymerase chain reaction (PCR)/denaturing high-pressure liquid chromatography (DHPLC) was used to detect the mutations and deletions. A blinded study of 110 samples, which included 92 alpha-thalassemia samples with various genotypes and 18 normal DNA samples, was carried out by the methods. The duplex PCR products of the sample with known Constand spring mutation (CS)/alphaalpha, Quonsze mutation (QS)/alphaalpha, and Weastmead mutation (WS)/alphaalpha DNA showed significantly different profiles, which suggests that DHPLC analysis at 63.8 degrees C can detect potential mutations directly. The DHPLC at 50 degrees C analysis can distinguish the --SEA and nondeletional alleles. The new assay is 100% concordant with the original genotype. In conclusion, the technique including the duplex PCR assay followed by DHPLC analysis can be used to diagnose alpha-thalassemia; this methodology is simple, rapid, accurate, semiautomatic, and high output, and thus, it is suitable for large-scale screening.

Rapid diagnosis of the alpha-thalassemia-1 Southeast Asian type deletion using a single tube real-time SYBR-polymerase chain reaction combined with dissociation curve analysis.

Dear Sir, A single tube polymerase chain reaction (PCR) with three primers and SYBR GREEN1 combined with dissociation curve analysis was set up that can clearly differentiate between Hb Bart's hydrops fetalis, normal subjects and - -(SEA) heterozygotes. This method seems to be simpler than that using a two-tube real-time SYBR-PCR with two different primer sets followed by analyses of DeltaC(T) and C(T) ratio.

Improvement in the detection of alpha0- and deletional alpha-thalassemia by real-time PCR combined with dissociation curve analysis.

The prevailing cause of alpha-thalassemia in Southeast Asia is the presence of 3 deletion mutations in the alpha-globin genes (-SEA, -alpha(3.7) and -alpha(4.2)). Current detection methods include gap polymerase chain reaction (PCR), multiplex PCR and real-time PCR with SYBR Green 1 combined with dissociation curve analysis. To improve and simplify a previously published method that requires 4 separate reactions, a duplex PCR assay was designed to detect both the nondeletional and the -SEA alleles. This duplex PCR can successfully identify the nondeletional allele and both the -SEA carrier and homozygous genotypes. The combination of the duplex PCR and 2 gap PCRs (for detection of -alpha(3.7) and -alpha(4.2)) can diagnose all types of deletional alpha-thalassemia. Our method was validated by analysis of 195 DNA samples, the results of which were consistent with prior diagnoses. The developed assay can reliably diagnose alpha0-thalassemia and all types of deletional alpha-thalassemia. The diagnostic method is simple, rapid, accurate, automated, inexpensive and has a high throughput.

[Detection of factor VIII intron 1 inversion in severe haemophilia A].

OBJECTIVE: Screening the intron 1 inversion of factor VIII (FVIII) in the population of severe haemophilia A(HA) in China and performing carrier detection and prenatal diagnosis. METHODS: Using LD-PCR to detect intron 22 inversions and multiple-PCR within two tubes to intron 1 inversions in severe HA patients. Carrier detection and prenatal diagnosis were performed in affected families. Linkage analysis and DNA sequencing were used to verify these tests. RESULTS: One hundred and eighteen patients were seven diagnosed as intron 22 inversions and 7 were intron 1 inversions out of 247 severe HA patients. The prevalence of the intron 1 inversion in Chinese severe haemophilia A patients was 2.8% (7/247). Six women from family A and 2 from family B were diagnosed as carriers. One fetus from family A was affected fetus. CONCLUSION: Intron 1 inversion could be detected directly by multiple-PCR within two tubes. This method made the strategy more perfective in carrier and prenatal diagnosis of haemophilia A.