BACKGROUND AND OBJECTIVE

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as the causative agent of COVID-19 has significantly challenged the public health landscape in late 2019. After almost 3 years of the first ever SARS-CoV-2 case, the World Health Organization (WHO) declared the end of this global health emergency in May 2023. Although, despite the subsequent drop of COVID-19 cases, the SARS-CoV-2 infection still exhibited multiple waves of infection, primarily attributed to the appearance of new variants. Five of these variants have been classified as Variants of Concern (VOC): Alpha, Beta, Gamma, Delta, and the most recent, Omicron. Therefore, the development of methods for the timely and accurate detection of viral variants remains fundamental, ensuring an ongoing and effective response to the disease. This study aims to evaluate the feasibility of the application of an in-house approach in genomic surveillance for the detection of SARS-CoV-2 variants using in silico designed primers.

The primers used for the study were particularly designed based on conserved regions of certain genes in the virus, targeting distinct mutations found in known variants of SARS-CoV-2. Viral RNA extracts from nasopharyngeal samples (n=14) were subjected to quantitative and qualitative tests (Nanodrop and AGE). Selected samples were then analyzed by RT-PCR and amplicons were submitted for sequencing. Sequence alignment analysis was carried out to identify the prevailing COVID-19 variant present in the sample population.

The study findings demonstrated that the in-house method was able to successfully amplify conserved sequences (spike, envelope, membrane, ORF1ab) and enabled identification of the circulating SARS-CoV-2 variant among the samples. Majority of the samples were identified as Omicron variant. Three out of four designed primers effectively bound into the conserved sequence of target genes present in the sample, revealing the specific SARSCoV-2 variant. The detected mutations characterized for Omicron found in the identified lineages included K417N, S477N, and P681H which were also identified as mutations of interest. Furthermore, identification of the B.1.448 lineage which was not classified in any known variant also provided the potential of the developed in-house method in detecting unknown variants of COVID-19.

Among the five VOCs, Omicron is the most prevalent and dominant variant. The in-house direct PCR product sequencing surveillance (DPPSS) method provided an alternative platform for SAR-CoV-2 variant analysis which is accessible and affordable than the conventional diagnostic surveillance methods and the whole genome sequencing. Further evaluation and improvements on the oligonucleotide primers may offer significant contribution to the development of a specific and direct PCRbased detection of new emerging COVID-19 variants.

BACKGROUND AND OBJECTIVE

Nontuberculous mycobacteria (NTM) lung disease appears like tuberculosis infection but is resistant to primary anti-tuberculosis drugs. Hence, patients whose sputum sample tests positive for acid-fast bacilli (AFB) and bacterial culture for several times should be assessed for colonization or infection with NTM in a damaged lung secondary to TB. In such cases, though drug-resistant TB may be adequately treated, treatment may need to be directed towards the NTM as well. In NTM therapy, the duration and choice of treatment agent is based upon the specific organism and disease extent. This study used one-step multiplex PCR (mPCR) assay for rapid differentiation of solid cultures in Ogawa medium as Mycobacterium tuberculosis (MTB) and/or NTM.

A total of 80 stocked isolates obtained from the Lung Center of the Philippines from January to December 2018 were screened for NTM in terms of growth in Ogawa medium, acid fastness, and MPT64 TB antigen test result. These were from sputum specimens of multidrug-resistant tuberculosis (MDR-TB) patients. DNA was extracted from cultures (n=55) grown in Ogawa medium and one-step mPCR was performed to identify NTM to the species level.

Out of 80 samples screened, a total of 55 isolates were identified as NTM. One-step mPCR identified 12.73% (7/55) as M. abscessus, 34.55% (19/55) as M. massiliense, 1.82% (1/55) as M. kansasii, and 50.91% (28/55) were identified only up to genus Mycobacteria spp. Neither M. avium complex nor M. intracellulare was identified among the samples tested.

One-step mPCR was able to identify isolates as MTB or NTM coinciding with the initial screening using MPT64 TB antigen test. Multiplex PCR has given a more specific identificati on to the species level. The use of mPCR in identifying MTB and clinically significant NTM’s is suitable for the adequate treatment of mycobacterial infection.

Human ; Bacteria ; Antimicrobial Stewardship ; Insemination, Artificial, Heterologous ; Multiplex Polymerase Chain Reaction ; Polymerase Chain Reaction

OBJECTIVES

To validate a method in detecting SARS-CoV-2 via RT-qPCR in pregnant and non-pregnant samples other than nasopharyngeal swabs and/or oropharyngeal swabs such as cervical, rectal, amniotic fluid, placental, umbilical cord blood, and breastmilk.

We performed a validation experiment using MGI easy extraction kits and BGI PCR kits on non-conventional specimens, including cervical, rectal, amniotic fluid, placental, umbilical cord blood, and breastmilk to detect and confirm the presence of SARS-CoV-2. In addition, we tested the validated method on 572 purposively sampled field-collected non-conventional specimens from a cohort of 109 unvaccinated pregnant and 47 unvaccinated non-pregnant women to assess which candidate non-conventional maternal- and fetal-associated specimens may contribute to maternal-fetal viral vertical transmission.

Positive detection of SARS-CoV-2 viral RNA in non-conventional specimens was demonstrated and verified. Of the 572 non-conventional samples tested, 1.8% (10/572) were positively validated by RT-qPCR for SARS-CoV-2 in the maternal-associated specimens particularly the rectal (5), placental (1), and cervical (4) swabs among six pregnant and four non-pregnant individuals. In contrast, no SARS-CoV-2 viral RNA was detected in fetal-associated specimens.

The results of the validation study may serve as an additional diagnostic screening layer to support maternal-child care. Furthermore, viral detection in these non-conventional maternal specimens may also be utilized to provide guidance in the clinical management of neonates, and pregnant women during delivery.

BACKGROUND

Broad  Panel Respiratory Multiplex PCR (Pneumonia Panel) tests a panel of bacteria and viruses associated with community acquired pneumonia (CAP) which help streamline antimicrobial therapy. Recently, pneumonia panel aids clinicians in early streamlining of antimicrobials as opposed to waiting for bacterial culture results [2].

To determine whether the use of pneumonia panel improves the overall survival rate, length of hospital stay, and number of antibiotic free days among hospitalized CAP patients.

In this RCT, adult patients admitted for CAP were randomized to perform pneumonia panel and sputum culture (pneumonia panel group) versus sputum culture only (control group). The results were relayed to the medical team and were incorporated into the medical records. Length of hospital stay, antibiotic free days in day 28, and mortality rates were the primary outcomes measured.

Eighty participants completed the study. There was no significant difference in the length of hospital stay (p-value 0.073, 95% C.I.), duration of antibiotic therapy (p-value 0.332, 95% C.I.), and mortality rates (p-value 0.570, 95% C.I.) between the 2 groups.

Routine use of pneumonia panel does not significantly reduce length of hospital stay, duration of antibiotic therapy, and mortality rates among admitted patients with moderate to severe CAP. The benefit of pneumonia panel was seen on early detection of drug resistant pathogen resulting in early antibiotic escalation and shorter duration of antibiotic therapy. Further studies are necessary to show its benefit in the high risk population.

Objective: To establish a rapid and specific quantitative real-time PCR (qPCR) method for the detection of SARS-CoV-2 subgenomic nucleocapsid RNA (SgN) in patients with COVID-19 or environmental samples. Methods: The qPCR assay was established by designing specific primers and TaqMan probe based on the SARS-CoV-2 genomic sequence in Global Initiative of Sharing All Influenza Data (GISAID) database. The reaction conditions were optimized by using different annealing temperature, different primers and probe concentrations and the standard curve was established. Further, the specificity, sensitivity and repeatability were also assessed. The established SgN and genomic RNA (gRNA) qPCR assays were both applied to detect 21 environmental samples and 351 clinical samples containing 48 recovered patients. In the specimens with both positive gRNA and positive SgN, 25 specimens were inoculated on cells. Results: The primers and probes of SgN had good specificity for SARS-CoV-2. The minimum detection limit of the preliminarily established qPCR detection method for SgN was 1.5×10² copies/ml, with a coefficient of variation less than 1%. The positive rate of gRNA in 372 samples was 97.04% (361/372). The positive rates of SgN in positive environmental samples and positive clinical samples were 36.84% (7/19) and 49.42% (169/342), respectively. The positive rate and copy number of SgN in Wild strain were lower than those of SARS-CoV-2 Delta strain. Among the 25 SgN positive samples, 12 samples within 5 days of sampling time were all isolated with virus; 13 samples sampled for more than 12 days had no cytopathic effect. Conclusion: A qPCR method for the detection of SARS-CoV-2 SgN has been successfully established. The sensitivity, specificity and repeatability of this method are good.
Humans ; SARS-CoV-2/genetics* ; COVID-19/diagnosis* ; Subgenomic RNA ; Real-Time Polymerase Chain Reaction/methods* ; RNA, Viral/genetics* ; Sensitivity and Specificity ; Nucleocapsid/chemistry* ; COVID-19 Testing

Objective: To analyze the characteristics of human papillomavirus (HPV) infection and the distribution of HPV subtypes in Shijiazhuang, Hebei Province, and to explore the application evaluation of multiple PCR capillary electrophoresis fragment analysis for HPV typing test. Methods: A population-based cross-sectional study was conducted among 434 women (age range 17 to 74 years old, 260 patients and 174 physical examinations) included from May to August 2022 in Hebei General Hospital. HPV typing was detected by multiple PCR-capillary electrophoresis fragment analysis. Using the multiple fluorescence quantitative PCR kit as a reference, Chi-square test was used to analyze the diagnostic effect of multiple PCR-capillary electrophoresis fragment analysis, and the consistency was analyzed by Kappa value. Results: The total HPV infection rate was 45.85%(199/434), including 35.48% (154/434) of high-risk HPV (HR-HPV), 3.92% (17/434) of low-risk HPV (LR-HPV), 6.45% (28/434) of HR-HPV and LR-HPV mixed infection, 27.88% (121/434) of single type HPV and 17.97% (78/434) of multi type HPV. HPV52 (9.68%, 42/434), HPV16 (6.91%, 30/434), and HPV58 (6.91%, 30/434) are common HPV subtypes. The positive rate of physical examination was 45.40% (79/174), which was slightly lower than that of patients 46.15% (120/260), there was no significant difference (χ²=0.024,P>0.05). The highest infection rate in the 17-30 age group was 54.76% (46/84), and there was no statistical difference among the age groups(χ²=4.123,P>0.05). The sensitivity and specificity of multiplex PCR capillary electrophoresis fragment analysis were 92.96% and 94.04%, respectively, and Kappa value was 0.870, with the multiplex fluorescent quantitative PCR as the reference. Conclusion: HPV infection may appear younger, and the positive rate of HR-HPV infection is the highest, with HPV52, 16, 58 as the main infection subtypes. The detection results of multiplex PCR capillary electrophoresis fragment analysis method are highly consistent with those of multiplex fluorescent quantitative PCR method, which is suitable for HPV DNA typing.
Humans ; Female ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Uterine Cervical Neoplasms ; Multiplex Polymerase Chain Reaction ; Papillomavirus Infections/diagnosis* ; Cross-Sectional Studies ; Genotype ; Papillomaviridae/genetics*

Gelsemium elegans is a traditional Chinese herb of medicinal importance, with indole terpene alkaloids as its main active components. To study the expression of the most suitable housekeeping reference genes in G. elegans, the root bark, stem segments, leaves and inflorescences of four different parts of G. elegans were used as materials in this study. The expression stability of 10 candidate housekeeping reference genes (18S, GAPDH, Actin, TUA, TUB, SAND, EF-1α, UBC, UBQ, and cdc25) was assessed through real-time fluorescence quantitative PCR, GeNorm, NormFinder, BestKeeper, ΔCT, and RefFinder. The results showed that EF-1α was stably expressed in all four parts of G. elegans and was the most suitable housekeeping gene. Based on the coexpression pattern of genome, full-length transcriptome and metabolome, the key candidate targets of 18 related genes (AS, AnPRT, PRAI, IGPS, TSA, TSB, TDC, GES, G8H, 8-HGO, IS, 7-DLS, 7-DLGT, 7-DLH, LAMT, SLS, STR, and SGD) involved in the Gelsemium alkaloid biosynthesis were obtained. The expression of 18 related enzyme genes were analyzed by qRT-PCR using the housekeeping gene EF-1α as a reference. The results showed that these genes' expression and gelsenicine content trends were correlated and were likely to be involved in the biosynthesis of the Gelsemium alkaloid, gelsenicine.
Genes, Essential ; Gelsemium/genetics* ; Peptide Elongation Factor 1/genetics* ; Transcriptome ; Gene Expression Profiling/methods* ; Alkaloids ; Real-Time Polymerase Chain Reaction/methods* ; Reference Standards

OBJECTIVE: To analyze the serological characteristics and molecular mechanism for an individual with p phenotype. METHODS: An individual with p phenotype upon blood group identification at Jiaxing Blood Center in May 2021 was analyzed. ABO, RhD and P1PK blood groups and irregular antibodies in her serum were identified using conventional serological methods. The encoding region of α1, 4-galactosyltransferase gene (A4GALT) encoding P1 and Pk antigens was analyzed by polymerase chain reaction-sequence-based typing (PCR-SBT). RESULTS: The individual was A group, RhD positive and had a p phenotype of the P1PK blood group system. Anti-PP1Pk was discovered in her serum. Sequencing analysis revealed that she has harbored a homozygous c.343A>T variant of the A4GALT gene. CONCLUSION The homozygous c.343A>T variant of the A4GALT gene probably underlay the p phenotype in this individual.
Female ; Animals ; Blood Group Antigens ; Homozygote ; Phenotype ; Polymerase Chain Reaction ; Sequence Analysis, DNA

Mycoplasma species (spp.) are bacteria that are difficult to detect. Currently, the polymerase chain reaction (PCR) is considered the most effective diagnostic tool to detect these microorganisms in both human and veterinary medicine. There are 13 known species of human Mycoplasma and 15 species of canine Mycoplasma. Owing to the difficulties in identifying the individual species of Mycoplasma, there is a lack of information regarding which species are saprophytic and which are pathogenic. The prevalence of the individual species is also unknown. In addition, in both humans and dogs, the results of some studies on the impact of Mycoplasma are conflicting. The presence of Mycoplasma spp. on the epithelium of reproductive tract is often associated with infertility, although they are also detected in healthy individuals. The occurrence of Mycoplasma spp. is more common in dogs (even 89%) than in humans (1.3%-4%). This is probably because the pH of a dog's genital is more conducive to the growth of Mycoplasma spp. than that of humans. Phylogenetically, human and canine Mycoplasma are related, and majority of them belong to the same taxonomic group. Furthermore, 40% of canine Mycoplasma spp. are placed in common clusters with those of human. This suggests that species from the same cluster can play a similar role in the canine and human reproductive tracts. This review summarizes the current state of knowledge about the impact of Mycoplasma on canine and human male fertility as well as the prospects of further development in this field.
Humans ; Dogs ; Male ; Animals ; Mycoplasma/genetics* ; Infertility ; Semen Analysis ; Polymerase Chain Reaction/methods* ; Prevalence ; Semen/chemistry*