Performance of a targeted cell-free DNA prenatal test for 22q11.2 deletion in a large clinical cohort.

OBJECTIVE: 22q11.2 deletion is more common than trisomies 18 and 13 combined, yet no routine approach to prenatal screening for this microdeletion has been established. This study evaluated the clinical sensitivity and specificity of a targeted cell-free DNA (cfDNA) test to screen for fetal 22q11.2 deletion in a large cohort, using blinded analysis of prospectively enrolled pregnancies and stored clinical samples. METHODS: In order to ensure that the analysis included a meaningful number of cases with fetal 22q11.2 deletion, maternal plasma samples were obtained by prospective, multicenter enrolment of pregnancies with a fetal cardiac abnormality and from stored clinical samples from a research sample bank. Fetal genetic status, as evaluated by microarray analysis, karyotyping with fluorescence in-situ hybridization or a comparable test, was available for all cases. Samples were processed as described previously for the Harmony prenatal test, with the addition of DANSR (Digital Analysis of Selected Regions) assays targeting the 3.0-Mb region of 22q11.2 associated with 22q11.2 deletion syndrome. Operators were blinded to fetal genetic status. Sensitivity and specificity of the cfDNA test for 22q11.2 deletion were calculated based on concordance between the cfDNA result and fetal genotype. RESULTS: The final study group consisted of 735 clinical samples, including 358 from prospectively enrolled pregnancies and 377 stored clinical samples. Of 46 maternal plasma samples from pregnancies with a 22q11.2 deletion, ranging in size from 1.25 to 3.25 Mb, 32 had a cfDNA result indicating a high probability of 22q11.2 deletion (sensitivity, 69.6% (95% CI, 55.2-80.9%)). All 689 maternal plasma samples without a 22q11.2 deletion were classified correctly by the cfDNA test as having no evidence of a 22q11.2 deletion (specificity, 100% (95% CI, 99.5-100%)). CONCLUSIONS: The results of this large-scale prospective clinical evaluation of the sensitivity and specificity of a targeted cfDNA test for fetal 22q11.2 deletion demonstrate that this test can detect the common and smaller, nested 22q11.2 deletions with a low (0-0.5%) false-positive rate. Although the positive predictive value (PPV) observed in this study population was 100%, the expected PPV in the general pregnant population is estimated to be 12.2% at 99.5% specificity and 41.1% at 99.9% specificity. The use of this cfDNA test to screen for 22q11.2 deletion could enhance identification of pregnancies at risk for 22q11.2 deletion syndrome without significantly increasing the likelihood of maternal anxiety and unnecessary invasive procedures related to a false-positive result. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

[Effect of flogensim in the treatment of postischemic inflammation (according to results of using interleukin-6 in patients with acute brain infarction)].

I1-6 in blood serum 109 patients with ischemic stroke was tested on 1st and 7 day after developing the disease. The decrease in concentration of I1-6 on 7 day was found after a complex therapy with Flogensim in the study group in comparison with the control group where a traditional therapy was used. The authors found considerable difference in consequences of the ischemic stroke on 21 day among patients pertaining to different group: the number of patients of the study group where results were better increases and number of the patients of this group with no dynamic or even worsening in neurological status decreases.

Molecular characterization of severe alpha-thalassemias causing hydrops fetalis in Taiwan.

alpha-Thalassemia hydrops fetalis is a common disorder in Taiwan. The condition causes perinatal death and many maternal obstetrical complications. In order to determine the molecular defects of this condition in Chinese, 87 unrelated families with this disorder were collected in the past 4 years. The molecular defects were studied by Southern blotting and DNA hybridization with phi zeta 1-globin gene and LO (a 0.4 kb BamHI/EcoRI fragment in the 5' flanking region of the zeta 2-globin gene) probes. Eighty-one (93.1%) fetuses had homozygous Southeast Asian deletion (- -SEA/- -SEA). Five (5.7%) fetuses were compound heterozygotes for the Southeast Asian deletion and Thailand deletion (- -SEA/- -THAI). The remaining fetus was a compound heterozygote for the Southeast Asian deletion and an uncharacterized nondeletional defect (- -SEA/(alpha alpha)Th). The molecular defects of alpha-thalassemia hydrops fetalis in Chinese are heterogeneous. This fact has important implications for genetic counseling and prenatal diagnosis.

Surface characterization and platelet adhesion studies of plasma-sulphonated polyethylene.

Canine platelet adhesion on sulphur dioxide and allyl phenyl sulphone plasma-treated low density polyethylene (LDPE) was studied. Both 5 W plasma excitation energy-treated surfaces showed the highest S:C atomic ratio by ESCA analysis. Surface hydrophilicity increased drastically after plasma treatment. However, surface hydrophilicity decreased with time. This might be due to the diffusion of the hydrophilic functional groups into the bulk of the material and/or the migration of low molecular weight hydrocarbon species into the surface region. The allyl phenyl sulphone plasma-treated LDPE was less platelet-activating in terms of platelet adhesion and spreading and was independent of the different plasma excitation energy levels used. Sulphur dioxide plasma-treated LDPE showed a higher level platelet activation than the untreated LDPE. Among the sulphur dioxide plasma-treated LDPE samples, the sample prepared using the 5 W excitation energy was less platelet-activating than the samples treated by higher plasma excitation energies.

Doppler velocimetry of intraplacental fetal arteries.

Doppler velocimetry of the umbilical and intraplacental fetal arteries was studied by color flow mapping in 39 normal pregnancies. The systolic-diastolic ratio (S/D) and pulsatility index of the intraplacental fetal artery downstream to the umbilical artery decreased significantly with advancing gestational age, and its S/Ds were persistently lower than those of the umbilical artery. The difference in the S/D between the umbilical artery and its intraplacental downstream branches decreased with advancing gestational age and approached zero as the pregnancy progressed to term. We conclude that intraplacental fetal arteries, possibly fetal arteries in main stem villi, can be imaged by color flow mapping and that there is a significant "resistance gradient" between the intraplacental fetal artery and the umbilical artery. Intraplacental fetal artery velocimetry using color flow mapping may give further insights into the umbilical-placental circulation.

Umbilical vein blood flow measurement in nonimmune hydrops fetalis.

Twenty-five measurements of fetal umbilical vein blood flow were performed in 22 cases of nonimmune hydrops fetalis using real-time and pulsed Doppler duplex ultrasound. The umbilical vein diameter, blood velocity, and blood flow in fetuses with hemoglobin Bart's hydrops fetalis were usually higher than those in fetuses with hydrops fetalis from other causes. Umbilical vein blood flow measurement appears to be an effective technique for differentiating hemoglobin Bart's from non-Bart's hydrops in this series. This hemodynamic characteristic of umbilical vein blood flow may be helpful in determining the etiology of nonimmune hydrops fetalis.

The antenatal blood gas and acid-base status of normal fetuses and hydropic fetuses with Bart hemoglobinopathy.

Funipuncture offers direct access to the fetal circulation. The blood gas and acid-base status of the fetus can be studied, and fetal hypoxia and acidosis can be diagnosed directly. To establish normal ranges of fetal blood gas and acid-base status, we analyzed umbilical venous blood samples obtained by funipuncture from 62 normal fetuses (20-35 weeks). These fetuses were studied because of suspected fetal diseases and were subsequently proved to be normal by the fetal blood examinations. Umbilical vein pH and pO2 decreased whereas pCO2 and bicarbonate increased with gestational age. The umbilical vein base excess did not correlate with gestational duration, but oxygen saturation tended to decrease with gestational age. Twenty hydropic fetuses with Bart hemoglobinopathy were also studied; they were found to be more acidotic, hypoxic, and hypercarbic than normal fetuses.

Transmission of de novo mutations of the deleted in azoospermia genes from a severely oligozoospermic male to a son via intracytoplasmic sperm injection.

OBJECTIVE: To investigate the transmission of microdeletions in the deleted in azoospermia (DAZ) genes to a male offspring via intracytoplasmic sperm injection (ICSI). DESIGN: Case report. SETTING: Reproductive unit of a university teaching hospital. PATIENT(S): A 29-year-old, severely oligozoospermic male with microdeletions of the DAZ genes in Yq interval 6 and his son, who was conceived via ICSI. INTERVENTION(S): DNA screening for the microdeletions in Yq interval 6 with 24 sequence tagged sites with the use of polymerase chain reaction amplification for the patient, the patient's father, and the patient's son. Paternity identification was performed using nine hypervariable short tandem repeats. MAIN OUTCOME MEASURE(S): Deletion mapping of Yq interval 6 from sequence tagged sites and electropherogram of short tandem repeats for DNA fingerprinting. RESULT(S): The son had the same microdeletions of the DAZ genes as the patient, and the patient's father had normal DAZ genes. The paternity of the patient, the patient's father, and the patient's son was verified. CONCLUSION(S): De novo DAZ microdeletions in an infertile male can be transmitted to a male offspring via ICSI. DNA screening tests for DAZ genes before ICSI may help in the genetic counseling of patients with idiopathic azoospermia or severe oligozoospermia.

Norplant subdermal contraceptive system: experience in Taiwan.

From November 1988 to December 1994, a total of 567 female volunteers were enrolled in Norplant implant studies at the National Taiwan University Hospital. After a median follow-up of 29 months, only 3 of the 529 available cases became pregnant (a cumulative rate of 1.2 pregnancies per 100 users over 5 years). Chromosome analysis of 2 of the 3 abortuses revealed 46,XX/46,XX,inv(3) and 46,XX. Menstrual problems were the most common adverse effects and were also the main reason for discontinuation (65%, 108/166). The continuation rate was 90%, 78%, 70%, 61%, and 42% at the end of 1, 2, 3, 4, and 5 years after insertion, respectively. In the 21 patients who wished to become pregnant, fertility recurred soon after removal of the Norplant implants. The data suggested that the Norplant implants system is a highly effective, safe, and long-acting method of reversible contraception. It would be worthwhile to introduce this contraceptive system to Taiwan's family planning program.

PIP: Between November 1988 and December 1994 health providers at the National Taiwan University Hospital enrolled 567 women aged 17-47 in the Norplant implant studies that aimed to evaluate the benefits and side effects of Norplant as another contraceptive method choice. They followed the women for a median of 29 months. 38 cases were lost to follow-up. The 5-year contraceptive effectiveness rate was 98.8%. The 3 pregnancies (2 intrauterine and 1 ectopic) occurred during the 24th, 45th, and 47th months of use. None of the women who became pregnant weighed more than 70 kg. Two of the aborted fetuses had chromosomal abnormalities (46,XX/46,XX,inv(3) and 46,XX). 29.9% of the Norplant users had menstrual problems. Even though irregular bleeding occurred to 19.7% of Norplant users, hemoglobin levels increased after Norplant use (p 0.05). Triglycerides and total cholesterol levels decreased (p 0.05). None of the women developed thromboembolism. The Norplant continuation rate was 89.7% at 1 year, 78% at 2 years, 70% at 3 years, 61% at 4 years, and 42.4% at 5 years. The leading reason for implant removal was menstrual problems (108). The implants were removed during one sitting without x-ray or ultrasound identification in all 166 women who stopped using Norplant before 5 years and the 16 women who stopped using it at the end of 5 years. 78% of women who discontinued Norplant to become pregnant were pregnant within one year following removal. All their infants were normal. These findings suggest that Norplant is a safe, effective, and acceptable contraceptive method and that the family planning program should introduce Norplant to its contraceptive mix.

Hydrops fetalis caused by severe alpha-thalassemia.

Alpha-thalassemia is a prevalent condition in South East Asia and spreading because of increasing immigration. Hemodynamic study of Hb Bart's hydrops fetalis, the most severe form of alpha-thalassemia, showed the fetuses were in a hyperdynamic circulatory state and were also more acidotic, hypoxic, and hypercarvic than normal fetuses. The most common molecular defects of Hb Bart's hydrops fetalis was the Southeast Asia type deletion. Prenatal diagnosis of Hb Bart's hydrops fetalis and HbH diseases has been achieved using chorionic villi sampling or fetal blood sampling.

Modeling the stability of electroless plating bath--diffusion of nickel colloidal particles from the plating frontier.

Electroless nickel (EN) plating is a process in which Ni2+ ions are reduced by hydrogen atoms adsorbed at a fresh Ni surface. However, detaching of a handful of tiny Ni metal particles from a substrate causes the entrance of these particles into the plating solution. The metal particles offer very reactive surfaces for the reduction of Ni2+ ions, which in turn aggravates the detachment, causing a self-accelerated cycle. Eventually the plating solution will be subject to an overwhelming precipitation of Ni black. This paper proposes a one-dimensional diffusion model to explain the dependence of the bath stability on the plating time under different bath loadings. This mathematical model contains Vd, defined as the decomposition volume, a measure to judge chemical stability of a plating solution. To obtain Vd experimentally, a PdCl2 solution was purposely introduced into a model solution (the addition leads to immediate generation of metal particles) until the very moment of onset of massive deposition of colloidal Ni. The Vd data from the experiment were then used to perform simulation in order to complete the model proposed. Other than the effects of bath loadings and plating time, an adsorption model was also created to describe the temperature effect. To coordinate the adsorption model, l-cysteine was used as an adsorbate that plays a deactivation role. The under bump metallization process on patterned silicon wafers has been used to support the main theme of this study.

Leiomyosarcoma of the pulmonary vein.

OBJECTIVE: We report a case of leiomyosarcoma (LMS) of the pulmonary vein and comment on the natural history and determinants for survival for this rare condition. EXPERIMENTAL DESIGN: Our retrospective review is only the fourth such case reported in the world's literature. SETTING: A teaching hospital with an active surgical residency program. PATIENT OR PARTICIPANT: A 61-year-old female who presented with a central pulmonary mass. INTERVENTIONS: Complete resection without pneumonectomy of cardiopulmonary bypass. Pathology showed low grade LMS. MEASURES: Determinants for survival include complete surgical resection and a low mitotic activity of the tumor. RESULTS: The patient remains no evidence of disease three years following initial treatment. CONCLUSIONS: One reported case of LMS of the pulmonary vein had favorable determinants for survival; complete surgical resection and low mitotic activity of the tumor. These factors may have contributed to the successful outcome. The natural history of LMS of the pulmonary vein appears similar to the more widely studied LMS of the inferior vena cava.

Laminaria and sulprostone in second trimester pregnancy termination for fetal abnormalities.

The efficacy and safety of intracervical placement of laminaria and intravenous prostaglandin E2 (sulprostone) infusion for termination of second-trimester pregnancies with abnormal fetuses was investigated. One hundred and six pregnant women at 13-29 weeks' gestation with fetal anomalies underwent laminaria tent insertion into the cervical canal on admission. The next morning, Sulprostone infusion was started at a rate of 16 microg/h and increased by 16 microg/h every 30 min to induce uterine contractions. Induction-to-abortion time (IAT), success and complete abortion rates, and sulprostone-related side effects were registered. The overall success and complete abortion rates within 24 h were 91.5 and 80.2%, respectively. The mean IAT was 12.1+/-7.6 h. The incidence of nausea and/or vomiting was 17.9%, with 1.7 episodes per case. Diarrhea and fever (9.5%) were not common. Laminaria tent insertion plus sulprostone infusion was an effective and safe regimen for second-trimester termination of pregnancy with live fetuses.

Fluorescence microsatellite analysis to study the parental origin of the supernumerary chromosome in Down's syndrome.

OBJECTIVE: Down's syndrome (DS) is an important cause of mental retardation. This study investigated the parental origin of the extra chromosome 21 in DS patients. METHODS: Fourteen families each with a DS patient were recruited for analysis of nine microsatellite markers on chromosome 21. We collected DNA from both parents and the patient and used polymerase chain reaction to amplify nine segments on chromosome 21: D21S1435, D21S1436, D21S1437, D21S1446, D21S156, D21S258, D21S263, D21S265 and D21S270. One of each pair of DNA primers was labeled with a fluorescence dye. The amplified products were subjected to electrophoresis in a semi-automated DNA sequencer and then analyzed with Genescan software to determine the origin of the extra chromosome 21. RESULTS: The extra chromosome 21 originated from the mother in 13 (93%) patients and from the father in one (7%) patient. CONCLUSIONS: Our findings were compatible with those from Caucasian patients. A great majority of Down's syndrome cases resulted from meiotic errors in the eggs.

Complete androgen insensitivity syndrome. Molecular characterization in two Chinese women.

OBJECTIVE: To study the molecular basis of complete androgen insensitivity syndrome (AIS). STUDY DESIGN: The coding region of the human androgen receptor (hAR) gene in two women with AIS was amplified with polymerase chain reaction using 12 pairs of oligonucleotide primers and then sequenced with a dye terminator method. RESULTS: Both patients had mutation in exon E of the androgen-binding domain. In one patient, codon 732 GAC (aspartic acid) was changed to ACC (asparagine), and her CAG polyglutamine tract had 27 repeats. In the other patient, codon 765 GCC (alanine) was changed to ACC (threonine), and her CAG polyglutamine tract in exon A had 19 repeats. CONCLUSION: Except for CAG polyglutamine polymorphism, these two missense mutations were the only differences detected in the coding region of the hAR gene. Both mutations involved the CpG sequence, which has been regarded as a mutation hotspot. To the best of our knowledge, these two mutations have not been observed before in Chinese women. Elucidation of the molecular defects of AIS patients would be very helpful for genetic counseling and prenatal diagnosis.

Congenital adrenal hyperplasia. Molecular characterization.

OBJECTIVE: To study the molecular defects of congenital adrenal hyperplasia (CAH). STUDY DESIGN: Twenty Chinese patients, including 8 with salt-wasting (SW) type CAH, 11 with simple virilizing (SV) type CAH and 1 with nonclassical (NC) type CAH, were recruited. Two rounds of the polymerase chain reaction (PCR) were used to study the 21-hydroxylase gene (CYP21). The primary PCR amplified CYP21-specific DNA fragments, and the secondary PCR used products from the primary PCR for analysis of amplification-created restriction sites (ACRS) and direct DNA sequencing. In all patients, ACRS analysis was done at 12 possible mutation sites, and then direct DNA sequencing was performed to confirm or define the molecular defects. RESULTS: Ten different mutations, including nine point mutations and gross gene deletion or conversion, were found in this study. Of the nine point mutations, eight could be easily detected by ACRS analysis. The three most common mutations were codon (CD)172 t-->a (I172N), IVS-II 656 c/a-->g, and gross gene deletion or conversion, accounting for 27.5% (11/40 alleles), 25% (10/40) and 20% (8/40) of all identified mutations, respectively. All SW patients were compound heterozygotes of IVS-II 656, gross gene deletion or conversion, or other severe defects, including CDs236 (t-->a) (I236N)+ 237 (t-->a) (V237E)+ 239 (t-->a) (M239K), CD306 (+t), CD318 (c-->t) (Q318X) and CD356 (c-->t) (R356W) mutations. All SV patients had one allele with a CD172 (I172N) mutation. One allele of an NC patient had a CD183 (c-->g) (D183E) mutation, and the other allele was not defined. In the whole series, four alleles (10%) had more than one mutation. CONCLUSION: We found 10 different mutations in this study. The correlation between genotypes and phenotypes was compatible with the reported data. Two rounds of PCR and ACRS analysis may provide important information for genetic counseling, prenatal diagnosis and management of families at risk for CAH.

Molecular study and prenatal diagnosis of alpha- and beta-thalassemias in Chinese.

Thalassemia is one of the most common single gene diseases worldwide. Populations in southern China and Taiwan have high prevalence rates of alpha- and beta-thalassemias. This review summarizes the current status of molecular studies, carrier screening, and prenatal diagnosis of thalassemia in Chinese. There are three genotypes of alpha-thalassemia 1 and at least six of alpha-thalassemia 2 in Chinese. For alpha-thalassemia 1, the South-East Asian deletion is the most common, followed by the Thai then Philippino deletions. For alpha-thalassemia 2, the rightward deletion is the most common, followed by the leftward deletion, and the nondeletional defects Hb Constant Spring and Hb Quong Sze. Twenty-eight different beta-thalassemia mutations have been reported. Four mutations, IVS-II-654 (C-->T), codons 41/42 frameshift (-TCTT), and nonsense codons 17 (A-->T) and -28 (A-->G), account for more than 90% of mutant alleles. For detection of alpha-thalassemia, polymerase chain reaction-related techniques are mainly used. Southern blot hybridization is still useful, especially for prenatal diagnosis. For detection of beta-thalassemia mutations, analysis of amplification-created restriction sites and reverse dot blot hybridization have been extensively used. In Taiwan, a national screening program incorporating hematological and molecular biological methods for thalassemia detection in pregnant women has been in progress for 5 years. Prenatal diagnosis has been performed in more than 1,800 pregnancies, including 1,500 cases at risk for homozygous alpha-thalassemia 1 and 300 for beta-thalassemia major, resulting in early prenatal diagnosis and termination of pregnancies affected with homozygous alpha-thalassemia 1 and an approximately 70% decrease in the number of newborns affected with beta-thalassemia major. In mainland China, only one large-scale screening program is in place. Characterization of undefined alleles, a higher awareness of the disease among physicians and the general public, and improvement of the service network will be important for early prenatal diagnosis and prevention of the disease in the future.

Cytogenetic study of spontaneous abortions with the Giemsa banding method.

Among 102 spontaneous abortuses karyotyped, 29 were from parents with a history of unexplained recurrent spontaneous abortion (group A), and 73 were from parents without a history of recurrent spontaneous abortion (group B). The mean maternal ages of these two groups were not significantly different. The chromosomal aberration rate in group A was 48.3% and in group B was 53.4%. The difference was not significant. The most common chromosomal anomaly was autosomal trisomies in both groups, while monosomy X was more common in group B. The subsequent spontaneous abortion rate was also not significantly different between the two groups.

Pericentric inversions of chromosome 9 in Taiwanese fetuses.

Using trypsin-Giemsa banding, a total of 1,350 unrelated Chinese fetuses were studied for pericentric inversion of chromosome 9 [inv(9) (p11; q13)]. Sixteen cases (1.2%) were found to have this variant. The prevalence was higher than that in a previous report on Asians. All the fetuses with inv(9) were born with a normal phenotype.