Clinical laboratory最新文献

Background: There are 49 B alleles in the ISBT ABO blood group list. This study will describe a new missense mutation, c.784G>T, in exon 7 of the ABO in a Chinese individual.

Methods: A weak B was analyzed by serologic techniques. Exons 6 and 7 were sequenced directly through polymerase chain reaction-based typing (PCR-SBT). Subsequently, the heterozygous mutation sites in exon 7 were determined through cloning and sequencing. The mutated GTB proteins were expressed in HEK293F cells after being subcloned into a pCAG vector with a Strep-tag. The potential impact of the mutations on GTB stability was predicted using mCSM software, while UCSF Chimera X software was utilized for visualization of the mutation.

Results: The ABO blood typing of serologic characteristics showed weak B phenotype, and the heterozygous site ABO*B.01 (c.784G>T) in Exon 7 was identified by PCR-SBT analysis after TA cloning, which led to an alteration of Asp to Tyr at residue 262 in B glycosyltransferase. Like the ABO*BW.17 (D262Y), D262N also significantly de-creased ABO*B.01 expression and lead to GTB destabilizing.

Conclusions: The novel B allele with 784G>T caused an alteration of Asp to Tyr at residue 262 in B glycosyltransferase, affecting the expression of GTB protein and influencing GTB structural instability.

Background: Erythrocytes are susceptible to oxidative stress throughout their lifespan. While compounds like vitamin C can help mitigate oxidative stress, the exploration of natural herbal products continues to be a compelling area of research. To examine the impact of subfractions derived from acidified chloroform fractions of fenugreek (Trigonella foenum-graecum L.) on red blood cells in the presence of H2O2 as an oxidant, we assessed the factors associated with erythrocyte aging and oxidative stress.

Methods: The maceration technique was employed for extracting fenugreek seeds. Through chromatography, a total of 12 subfractions were isolated from the acidified chloroform extract of fenugreek seeds. Following an initial assessment, four subfractions exhibiting lower erythrocyte toxicity were chosen for further investigation. The objective was to evaluate their impact on erythrocyte aging by measuring the levels of phosphatidylserine (PS), sialic acid, CD47 on the erythrocyte surface, as well as oxidative stress biomarkers. The obtained results were presented as mean ± standard deviation (SD), and data analysis was performed by using ANOVA.

Results: The results of this study revealed, that among the 12 subfractions derived from the acidified chloroform fraction of fenugreek, four subfractions demonstrated protective effects against H2O2-induced hemolysis and oxidative stress. Furthermore, flow cytometry analysis indicated that treatment with three of these subfractions led to elevated levels of CD47 and reduced levels of phosphatidylserine on the surface of erythrocytes.

Conclusions: The results suggest that the subfractions of fenugreek extract which likely contain a higher concentration of flavonoids and a lower content of saponins could be responsible for the observed protection against erythrocyte aging processes. It appears that fenugreek seeds have the ability to safeguard human erythrocytes from oxidative damage by reducing oxidative stress, preserving the activity of antioxidative enzymes, and maintaining the integrity of erythrocyte structure.

Background: Maturity-Onset Diabetes of the Young (MODY) is an autosomal dominant disease, caused by muta-tions in the ABCC8 gene, chromosome 11.

Methods: A case suspected of MODY due to an ABCC8 mutation was examined using whole-genome exon high-throughput sequencing. Selected variant sites were validated via Sanger sequencing.

Results: A heterozygous mutation c.2060C>T (p.T687M) in exon 15 of the ABCC8 gene (Chr11-174494701) was identified in both the proband and the father. This mutation was initially linked to MODY based on clinical fea¬tures.

Conclusions: For patients with high suspicion of MODY, genetic test should conducted to improve their quality of life.

Background: Circulating levels of the antiangiogenic protein, vasoinhibin, derived from the proteolytic cleavage of prolactin (PRL), in prolactinoma are unknown, as is the molecular nature of its isoforms. Dimerization of recombinant vasoinhibin has been reported.

Methods: Vasoinhibin in a human serum sample was identified by using preparative electrophoresis with subsequent SDS-PAGE and Western blot analysis, as well as mass spectrometry (MS) and ELISA.

Results: MS identified a partial vasoinhibin sequence in a 14-kDa protein band from human serum, which eluted in the 28-kDa fraction from the preparative electrophoresis. Measurement of vasoinhibin levels by ELISA identified a concentration of 284 ng/mL at a PRL level of 9,850 ng/mL. Recombinant human vasoinhibin demonstrated dimerization and multimerization when analyzed directly by SDS-PAGE and Western blot analysis under reducing and non-reducing conditions, as well as after immunoprecipitation.

Conclusions: The vasoinhibin sequence was identified in a higher molecular weight fraction, corroborating experi-mental evidence showing the dimerization and aggregation of recombinant human vasoinhibin. This report is sig-nificant, regarding the higher risk of cardiovascular disease and mortality in male patients with hyperprolactin-emia as well as emerging reports of linking PRL and vasoinhibin levels in patients with prolactinoma with left ventricular dysfunction and Takotsubo syndrome.

Background: Malaria is a global disease caused by the transmission of the malaria parasite through the bites of infected Anopheles mosquitoes. There are 4 kinds of common malaria parasites, among which oval malaria is mainly prevalent in tropical West Africa, with a narrow distribution range, mainly imported cases in China, which is relatively rare. Because the morphology, attack cycle, recrudescence and relapse are similar to those of Plasmodium vivax and, therefore, is easily missed and misdiagnosed.

Methods: Malaria parasite-specific antigens were detected in whole blood samples using rapid diagnostic tests (RDT). Peripheral blood was used to prepare thick and thin smears, which were then stained with Giemsa for the identification of malaria parasites and different parasite morphologies under an oil microscope. Plasmodium species were identified using fluorescence quantitative PCR.

Results: The patient's RDT revealed two red response lines (only T2 positive), indicating a single or mixed infection of three types of malaria (Plasmodium vivax, Plasmodium malarie, Plasmodium ovale) excluding Plasmodium falciparum. Thick smears exhibited various stages of Plasmodium such as hypertrophic rings and gametocytes, while thin films displayed Plasmodium trophozoites, gametocytes, etc., resembling oval malaria. The patients were diagnosed with Plasmodium ovum infection through fluorescence quantitative PCR, and targeted treatment was administered.

Conclusions: The incidence of Plasmodium ovum infection is low, and there is a risk of overlooking or misdiagnosing the infection in laboratory tests. It is essential for laboratory staff to enhance their morphological recognition skills for Plasmodium and to integrate blood routine analysis, RDT, and PCR results in order to facilitate early diagnosis and prompt treatment.

Background: This study aimed to perform surveillance and identify antimicrobial resistance (AMR) in the most common pathogenic bacteria in a healthcare facility in Rabigh City, Saudi Arabia.

Methods: A total of 1,933 samples were processed from patients during the study period from January 2022 to June 2022. Identification and antimicrobial susceptibility of the cultured isolates were performed using the MicroScan system.

Results: Out of the 1,933 tested samples, 11.1% (n = 214) were positive for bacterial growth. A relatively higher percentage of isolates was recovered from patients older than 50 years (55.9%). Gram-negative bacteria (67.3%) were significantly more prevalent than Gram-positive bacteria (32.7%). The Gram-negative pathogenic bacteria comprised mainly Escherichia coli and Klebsiella pneumoniae, followed by Pseudomonas aeruginosa. Staphylococ-cus epidermidis and coagulase-negative staphylococci were found at relatively high abundance in Gram-positive bacteria. Increased resistance to carbapenem antibiotics was observed in K. pneumoniae. In Gram-positive bac¬teria, > 50% of the isolates of S. epidermidis were resistant to 13 tested antimicrobial agents.

Conclusions: This study provided an overview of the distribution of pathogenic bacteria and antimicrobial susceptibility of the prevalent Gram-negative and Gram-positive pathogenic bacteria in a major healthcare facility in Saudi Arabia. It highlights the importance of continuously monitoring AMR bacteria in healthcare settings to ensure the effective use of antibiotics for treatment.

Background: The purpose of clinical microbiology testing is to provide important information for clinical diagnosis and treatment. The correct collection, processing, and transportation of specimens are the key to the success of clinical microbiological examination.

Methods: Retrospective analysis was done on the composition and causes of unqualified microbial samples submitted by clinical departments from 2019 to 2020 at the Affiliated Hospital of Nantong University. The solutions were proposed from the perspective of nursing management.

Results: In 2019, the hospital received 64,244 clinical microbial specimens. The unqualified rate of samples was 8.96%, of which the unqualified sputum accounted for 84.74%. After strengthening the communication with the medical laboratory, increasing publicity and training, and improving the information system and other auxiliary monitoring functions, the unqualified rate of clinical microbial specimens was reduced to 6.05% in 2020.

Conclusions: Continuously improving the theoretical and practical abilities of nurses can reduce the unqualified rate of samples.

Background: Glucose levels are vital for indicating the body's sugar content, with imbalances leading to diseases like diabetes or hypoglycemia-related symptoms such as palpitations and fatigue.

Methods: This case series describes three cases of hypoglycemia identified in recent years, utilizing multiple glucose measurement methods and exploring strategies to eliminate interferences.

Results: Two cases of pseudo-hypoglycemia induced by PEGylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) and Evolocumab injections, and one case of true reactive hypoglycemia following a glucose tolerance test in a patient post-gastric bypass surgery.

Conclusions: For unusual hypoglycemia, collaboration with clinicians and multiple methods is crucial for accurate analysis to differentiate true from pseudo-hypoglycemia, ensuring precise diagnosis and optimal clinical service.

Background: HBsAg confirmatory testing is crucial for accurately diagnosing HBV infection and avoiding false positives. We compared the performance of human-derived and sheep-derived anti-HBs reagents in the Elecsys HBsAg confirmatory test (Roche Diagnostics, Germany).

Methods: Samples with a HBsAg COI of 0.9 or more underwent confirmatory testing with both reagents. Results showed a high overall agreement rate of 98% between human and sheep reagents.

Results: The average confirmation percentage with sheep anti-HBs was significantly lower than with human anti-HBs (6.9% vs. 20.0%, p = 0.002). Additionally, some strongly positive HBsAg samples could not be neutralized.

Conclusions: This suggests that the polyclonal antibodies in these reagents have different specificities and affinities for HBsAg epitopes. The findings emphasize the importance of reagent specificity and affinity to ensure accurate HBV diagnosis. Additional HBV markers and clinical context must be considered to confirm the diagnosis.