Prospective Investigation of Optical Genome Mapping for Prenatal Genetic Diagnosis.

BACKGROUND: Optical genome mapping (OGM) is a novel assay for detecting structural variants (SVs) and has been retrospectively evaluated for its performance. However, its prospective evaluation in prenatal diagnosis remains unreported. This study aimed to prospectively assess the technical concordance of OGM with standard of care (SOC) testing in prenatal diagnosis. METHODS: A prospective cohort of 204 pregnant women was enrolled in this study. Amniotic fluid samples from these women were subjected to OGM and SOC testing, which included chromosomal microarray analysis (CMA) and karyotyping (KT) in parallel. The diagnostic yield of OGM was evaluated, and the technical concordance between OGM and SOC testing was assessed. RESULTS: OGM successfully analyzed 204 cultured amniocyte samples, even with a cell count as low as 0.24 million. In total, 60 reportable SVs were identified through combined OGM and SOC testing, with 22 SVs detected by all 3 techniques. The diagnostic yield for OGM, CMA, and KT was 25% (51/204), 22.06% (45/204), and 18.14% (37/204), respectively. The highest diagnostic yield (29.41%, 60/204) was achieved when OGM and KT were used together. OGM demonstrated a concordance of 95.56% with CMA and 75.68% with KT in this cohort study. CONCLUSIONS: Our findings suggest that OGM can be effectively applied in prenatal diagnosis using cultured amniocytes and exhibits high concordance with SOC testing. The combined use of OGM and KT appears to yield the most promising diagnostic outcomes.

Controlled Ni-catalyzed mono- and double-decarbonylations of α-ketothioesters.

A method for Ni-catalyzed controlled decarbonylation of α-ketothioesters is described. Mono- and double-decarbonylations, which gave thioesters and thioethers, respectively, were selectively achieved by changing the ligand. A fundamental study of Ni-catalyzed decarbonylation of α-ketothioesters is presented.

Suzuki-Miyaura coupling of unstrained ketones via chelation-assisted C-C bond cleavage.

Herein, we report that unstrained ketones can be efficiently employed as electrophiles in Suzuki-Miyaura reactions via catalytic activation of unstrained C-C bonds assist by an N-containing directing group. A wide range of aromatic ketones directly coupled with boronic ester with excellent functional group tolerance. This strategy provides an alternative and versatile approach to constructing biaryls from unstrained ketones.

Synthesis of Acyl Azides from 1,3-Diketones via Oxidative Cleavage of Two C-C Bonds.

A metal-free PhI(OAc)2-mediated method for the synthesis of acyl azides through oxidative cleavage of 1,3-diketones is described. This method is shown to have a broad substrate scope, providing a useful tool for multiproduct synthesis in a single procedure. A possible reaction pathway is proposed based on mechanistic studies.

Directed Decarbonylation of Unstrained Aryl Ketones via Nickel-Catalyzed C-C Bond Cleavage.

The nickel-catalyzed decarbonylation of unstrained diaryl ketones has been developed. The reaction is catalyzed by a combination of Ni(cod)2 and an electron-rich N-heterocyclic carbene ligand. High functional group tolerance and excellent yields (up to 98%) are observed. This strategy provides an alternative and versatile approach to construct biaryls using an inexpensive nickel catalyst.

Two novel isovaleryl-CoA dehydrogenase gene mutations in a Chinese infant.

Isovaleric acidemia (IVA) is a rare inherited metabolic disease caused by a deficiency in isovaleryl-CoA dehydrogenase (IVD). Newborn screening with tandem mass spectrometry leads to early identification of individuals with risk of IVA. The family specific mutations are useful for prenatal diagnosis. Molecular genetic analysis helps to further confirm the clinical diagnosis of IVA. We describe here the clinical and metabolic features of a Chinese infant with early onset IVA. Sequence analysis of the IVD gene identifies compound heterozygous mutations in this patient, c.39G>A (p.W13X) nonsense mutation and c.597C>G (p.I199 M) missense mutation, both of which are previously unreported. Structural analyses suggest that the p.I199 M missense mutation may destabilize the IVD monomer structure and affect the interaction between IVD and flavin adenine dinucleotide. Both the clinical and genetic features of this patient help to further expand our knowledge of IVA.

Platelet volume indices have low diagnostic efficiency for predicting bone marrow failure in thrombocytopenic patients.

The aim of the present study was to evaluate the predictive efficiency of mean platelet volume (MPV) and platelet size deviation width (PDW) for bone marrow failure (BMF) in thrombocytopenic patients. Platelet count, MPV and PDW data were retrieved from the records of 574 unselected thrombocytopenic patients from between March 2010 and March 2011, of which 182 patients with a platelet count <20×10(9)/l were excluded from further study. A total of 392 valid thrombocytopenic patients were included in the present study and divided into two groups: 124 patients with idiopathic thrombocytopenia purpura (ITP) and 268 with BMF. The predictive efficiency of MPV and PDW were tested for the diagnosis of BMF. Significant differences were observed in the age distribution, platelet count, MPV and PDW between the ITP and BMF groups. The platelet count was positively correlated with MPV and PDW in the patients with ITP but not BMF. The negative-predictive values of MPV and PDW for BMF were 59.3 and 58.9%, respectively, with an MPV threshold of ≥11.0 fl and a PDW threshold of <16.0%. The positive-predictive values of MPV and PDW for BMF were 88.4 and 83.9%, respectively, with an MPV threshold <8.0 fl and a PDW threshold ≥17.5%. The areas under the curves (AUCs) of MPV and PDW were 0.281 and 0.700, respectively, for the diagnosis of BMF. The negative and positive-predictive values of MPV for BMF at different thresholds were not as conclusive as described in previous studies. MPV and PDW do not have sufficient specificity and sensitivity for the diagnosis of BMF in thrombocytopenic patients.

Acid-catalyzed skeletal rearrangement of epoxy alkynes: a fast access to highly functionalized allenes.

The acid-catalyzed reaction of epoxy alkyne involves an epoxide ring-opening attacked by pi-alkyne, leading to a semipinacol-type rearrangement. In this process, a type of carbon-carbon 3,3-migration of the alkyne system has been discovered, which is promoted both by epoxide inducing and hydroxide promoting. This transformation enables the fast synthesis of allenes in mild conditions.

Gold-catalyzed tandem cyclization/Friedel-Crafts type reactions toward furan derivatives.

A simple and convenient synthetic approach to furan derivatives 4 has been developed via gold-catalyzed tandem cyclization/Friedel-Crafts type reactions.

PtCl2-catalyzed tandem triple migration reaction toward (Z)-1,5-dien-2-yl esters.

A novel method for the selective synthesis of (Z)-1,5-dien-2-yl esters has been developed though Pt(II)-catalyzed tandem 1,2-acyl and 1,2-hydride migration, along with an allyl migration reaction of propargylic carboxylates with electronically unbiased internal alkynes. The unusual selectivity of 1,2-acyloxy migration was realized.

Opposite effects on tumor growth depending on dose of Achyranthes bidentata polysaccharides in C57BL/6 mice.

We report here the investigation on the effects of Achyranthes bidentata polysaccharides (ABPS) against Lewis lung cancer (LLC) in C57BL/6 mice. Depending on its doses administered in vivo, ABPS was shown to have inhibitory as well as stimulative effects on tumor growth in LLC-bearing C57BL/6 mice. ABPS at low dose could significantly inhibit LLC growth, while high dose treatment of ABPS stimulated, rather than inhibited, LLC growth in C57BL/6 mice. Tumor cell cycle analysis revealed that more tumor cells arrested at G2/M phase after daily low dose intraperitoneal injection of ABPS for consecutive 15 days. The spleen weight increased markedly in LLC-bearing C57BL/6 mice treated with high dose of ABPS. However, the spleen cytotoxicity activity was significantly despaired in mice of high dose treatment of ABPS. Furthermore, we demonstrated that the expressions of IL-6 mRNA and TNF-alpha mRNA were markedly up-regulated in spleens from mice treated with a high dose of ABPS by RT-PCR reactions, suggesting that the low dose of ABPS inhibits tumor growth via its effect on tumor cell cycle distribution, rather than activation of NK activity as previously suggested. We postulate that the stimulation of tumor growth by high dose of ABPS is associated with dysfunction of NK cell and up-regulation of IL-6 mRNA and TNF-alpha mRNA expression in murine spleen.

[Change in humoral immunological function and their clinical significance in patients with cerebral hemorrhage].

OBJECTIVE: To study the changes in humoral immunological function and their clinical significance in cerebral hemorrhage. METHODS: Among 115 cases of cerebral hemorrhage, there was low volume bleeding in 39 case, middle volume in 37 cases, and large volume in 39 cases. The ratios of CD19+-CD25+ and CD19+-CD25-B lymphocytes were determined by flow cytometry, and the content of IgA, IgG, IgM, and complement C3 were determined with scattered turbidimetry. The changes in humoral immunological function were compared in patients with different degrees of hemorrhage, and their variation in acute and recovery stages of disease were respectively assessed. RESULTS: The ratios of CD19+-CD25+and CD19+-CD25-B lymphocyte, and the levels of IgA, IgG, IgM, and C3 were higher than those of controls (all P<0.05). The ratios of CD19+-CD25+ and CD19+-CD25- B lymphocyte, and the contents of IgA, IgG,IgM and C3 were increased with the increase in amount of hemorrhage(all P<0.05). The ratios of CD19+-CD25+ and CD19+-CD25-B lymphocytes in recovery stage were lower than those in acute stage (all P<0.05). CONCLUSION: There are activations of humoral immunological functions in cerebral hemorrhage. The more abundant in hemorrhage and the severer in disease, the more predominant in the changes in humoral immunological functions.

Immunophenotypic characterization of normal peripheral blood B lymphocyte by flow cytometry: reference for diagnosis of chronic B cell leukemia/lymphoma.

To establish reference values of various immunophenotypic markers in B lymphocyte population in healthy Chinese adults and build background information for accurate interpretation of B cell immunophenotyping data in clinical practice, peripheral blood from 41 healthy adults were collected separately into test tubes containing EDTA-K(2) and stored in room temperature no more than 24 hours before analysis. Whole blood lysis technique and multiparameter flow cytometry were applied to immunophenotype B cells gated on CD19/SSC dot-plot. The results showed that CD22, CD20, CD62L, CD40, CD24, CD79b, CD79a, and FMC-7 were almost positive in the circulating B cell population, whereas CD11a, CD80, CD103, CD10, CD40L, CD54, CD95L, CD86, and CD95 were almost negative in the peripheral blood B lymphocytes. CD18, CD44, CD23, CD5, CD11c and CD43 were positive in different B cell subpopulations. 78% of B cells were IgD positive and ratio kappa/lambda was 1.26. The significance of all these markers in the differential diagnosis of lymphoproliferative diseases was discussed. The conclusion is that it is necessary to consider the qualitative and quantitative levels of expression of various markers in normal B cell population in order to accurately interpret the pathological immunophenotypic data in clinical practice. It is also important to note the immunotypic differences of B cells between Chinese and Western populations.