Tip Culture Research Articles

Efficacy of Plant Tissue Culture Techniques for Eliminating Black Mulberry Idaeovirus (BMIV) from Infected Black Mulberry (Morus nigra)

Obtaining virus-free plants is a crucial step in disease management that enables reliable and profitable fruit farming. The present study applied various in vitro virus elimination protocols, including apical shoot culture, chemotherapy, thermotherapy, cryotherapy, and their combination, to eliminate black mulberry Idaeovirus (BMIV) from sour black mulberry. First, a shoot tip (0.5–2 mm) culture protocol was optimized, and four ribavirin concentrations (0, 10, 20, and 30 mg/L) were investigated over five weeks as a form of chemotherapy (ch). For the first thermotherapy treatment (Ch + Th1st), chemotherapy treatment was followed by a gradual increase in the temperature (24–33 °C). In another experiment (Th2nd + Ch), in vitro shoots were incubated in the dark for two weeks at two different temperatures (35 ± 1 °C and 37 ± 1 °C, for one week each). Subsequently, the shoot tips were incubated with various ribavirin doses. Finally, cryotherapy (Cr) was used with or without immersing the shoot tips in liquid nitrogen. A two-step RT-PCR was performed to assess the presence of the virus in 7–8-week-old in vitro plants. Th2nd + Ch significantly increased the shoot tip burst and plant survival/morphogenesis compared to the other treatments. Except for the application of cryotherapy, the protocols eliminated BMIV in different proportions, and the highest virus elimination rate (50%) was obtained by applying 30 mg/L ribavirin during the Ch + Th1st treatment. These findings are essential in preventing the dissemination of the virus and enabling the safe movement of germplasm around the world.

Micropropagation of Selected Hybrid Tomato (Solanum lycopersicum L.) Varieties Using Shoot Tip Culture

Tomato (Solanum lycopersicum L.) is one of the most important vegetable crops in the world. The use of hybrid varieties is a great option to increase its production but using F2 seed leads to lack of uniformity as a result of segregation. Therefore mass propagation using tissue culture could help to solve these problems. The objective of this study was to develop an optimum micropropagation protocol for Valouro, Uwezo and Shelter hybrid tomato varieties using shoot tip culture. Three successive experiments: shoot initiation; shoot multiplication and root inductions were conducted. Different concentrations of BAP (0.0, 0.25, 0.5, 0.75, 1.0 and 1.25 mg/l) and (0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3 mg/l) were used for shoot initiation and shoot multiplication, respectively. While different concentrations of IBA (0.0, 0.25, 0.5, 0.75, 1.0, 1.25 and 1.5 mg/l) were used for root induction. The three separate experiments were laid out as factorial arranged in completely randomized design. The result of shoot initiation showed that the interaction of BAP*Varieties highly significant (P<0.01) effect. In the multiplication experiment, all parameters showed highly significant difference (P<0.01). In rooting experiment the interaction effect of IBA*Variety showed highly significant difference for the studied parameters. In conclusion MS medium without growth regulators was the optimum for shoot initiation. For shoot multiplication experiment 2mg/l, 0.5mg/l and 1.5mg/l of BAP was the optimum concentration for number of shoots per explant, shoot length, and leaf number respectively. For in vitro rooting MS medium containing 0.5 mg/l IBA was optimum for all varieties.

First report of Fusarium falciforme causing root and stem rot in cowpea (syn. black-eyed pea; Vigna unguiculata) in California.

In both April 2018 and September 2019, cowpeas / black-eyed peas (Vigna unguiculata) in one field in Tulare County, California were observed with tap root rot, both underground (foot) and aboveground stem rot, and in some cases canopy decline, compromising bean formation. In both fields, < 5% of plants appeared affected. Foot and stem segments (~1 cm) of 5-10 plants / field were disinfested sequentially with 0.1% Tween 20 (dip), 70% ethanol for 30 s, and 1% sodium hypochlorite for 2 min and placed on 1:10 potato dextrose agar with 0.03% tetracycline and Fusarium selective medium (Leslie and Summerell 2006). Fusarium-like isolates (dominant in isolation plates) were transferred to 0.6% KCl agar, where fusiform, curved macroconidia and varied microconidia in false heads on elongated monophialides were observed, characteristic of the Fusarium solani species complex (FSSC) (Leslie and Summerell 2006). Isolates CS221, CS222, and CS520 (representing different plants and locations) were saved as single hyphal tip cultures. An Illumina-derived genome sequence was assembled (Burkhardt et al. 2019) and partial tef1ɑ and rpb2 sequences (O'Donnell et al. 2022) were extracted from genome sequences in silico. Sequences were 99.9-100% identical to one another and to deposited F. falciforme isolates based on Fusarium ID and Fusarium MLST for tef1ɑ and rpb2, respectively (tef1a accessions: NRRL 28562 and NRRL 32331; rpb2 accession: NRRL 22857), and were deposited in GenBank (accessions in supplementary table). Pathogenicity was evaluated in three-week-old cowpea plants (cv. CB46rk2) in the greenhouse (13.5-33.6℃; 12:12 h L:D). The tap root / stem was wounded (1 mm wide, 2 mm deep) ~ 2 cm below the soil line and drenched with 50 ml of 106 spores / ml 0.1% water agar or with 0.1% water agar (negative control). The trial was arranged in a Randomized Complete Block Design with three blocks and 2-3 plants / isolate / block, and conducted twice. 52 d post-inoculation, below ground tap root / stem rot developed in 83% of F. falciforme-inoculated plants, with lesion lengths ranging from 25.2 ± 4.2 to 29.2 ± 8.0 mm (P = 0.893 for isolate, ANOVA). Canopy decline developed in 33-50% of plants across treatments in trial 1 (P = 0.859 for isolate) but not in trial 2, likely due to cooler conditions in trial 2 (January-March) vs. trial 1 (May-July), which were less stressful. F. falciforme isolates did not affect bean biomass (dry weight) vs. negative controls (12.5-14.8g / plant; P = 0.949 for pathogen treatment). FSSC isolates were recovered from 100% of symptomatic plants in the inoculated treatments but not in negative controls (both trials) and representative isolates from all treatments were confirmed as F. falciforme (tef1a analysis; trial 2 only). This study establishes F. falciforme as a root and stem rot pathogen of cowpea in California-a disease previously attributed to the morphologically and phylogenetically distinct F. phaseoli (syn. F. solani f. sp. phaseoli), but which lacked modern etiological studies (Frate et al. 2018; Geiser et al. 2021). This work is consistent with previous reports of F. falciforme as a root / stem rot pathogen in cowpea (Ajamu et al. 2023) and other beans (Sousa et al. 2017; Duarte et al. 2019). Clarification of disease etiology will improve accurate diagnosis and effective crop rotation-based management, since F. falciforme is also a pathogen of other California crops including melon, tomato and pistachio.

The Elimination of Viroids through In Vitro Thermotherapy and a Meristem Tip Culture from a New Limonime Hybrid (Citrus x limon var. limon (L.) Burm. f. x Citrus latifolia var. latifolia)

Viruses and viroids pose a significant challenge in citriculture, and their control is crucial for plant health. This study evaluated the effectiveness of in vitro thermotherapy combined with a meristem tip culture for eliminating citrus exocortis viroid (CEVd) and hop stunt viroid (HSVd) from a new limonime hybrid (Citrus x limon var. limon x Citrus latifolia var. latifolia). The elimination success was confirmed by RT-PCR assays. The in vitro elimination rate for CEVd during the shoot proliferation stage (43%) was higher than for HSVd (21%). Accordingly, in the subsequent rooting stage, the in vitro elimination rate for CEVd (50%) was higher than for HSVd (33%). Successful CEVd and HSVd eradication at a 100% rate was confirmed in the ex vitro acclimatized plants in the greenhouse. The study also established an efficient micropropagation protocol. The optimal treatment for in vitro shoot induction was 0.5–2 mg L−1 benzyladenine (BA) + 0.5 mg L−1 gibberellic acid (GA3) + 0.25 mg L−1 naphthalene acetic acid (NAA), while for shoot elongation, it was 0.5 mg L−1 BA + 0.5 mg L−1 kinetin (KIN) + 0.5 mg L−1 GA3 + 0.25 mg L−1 NAA. Rooting was best promoted by 1 mg L−1 NAA. This study provides valuable insights for the mass production of viroid-free propagation material in this new lemon x lime hybrid, contributing to the conservation of genetic resources in citrus breeding programs through the combined application of in vitro thermotherapy and an in vitro meristem tip culture, a novel and highlighted achievement reported for the first time in this study.

Combining Thermotherapy with Shoot Tip Culture or Cryotherapy for Improved Virus Eradication from In Vitro Actinidia macrosperma.

In recent years, kiwifruit viral diseases have become increasingly prevalent in kiwifruit-producing regions of China, significantly impacting both the yield and quality of kiwifruit. This has emerged as a significant constraint on the healthy and sustainable development of the kiwifruit industry. The use of virus-free propagation materials has been proven the most effective strategy for controlling plant viral diseases. In the present study, shoot tip culture, shoot tip cryotherapy, and their combinations with thermotherapy were established to eradicate Actinidia virus A (AcVA), Actinidia virus B (AcVB), and Actinidia chlorotic ringspot-associated virus (AcCRaV) from Actinidia macrosperma. Additionally, the impact of shoot tip size on virus eradication was evaluated. Among the three confirmed viruses, regardless of the procedure, AcVB was the easiest to eradicate, followed by AcVA and AcCRaV. Combining thermotherapy with shoot tip culture or cryotherapy resulted in a higher virus-free frequency (up to 27.3 and 50%, respectively) than shoot tip culture or cryotherapy alone (0 to 20%). Notably, the combination of thermotherapy and 0.5- to 1-mm shoot tip cryotherapy was shown to be the most effective protocol for virus eradication from A. macrosperma, which produced 50% of regenerated shoots free from all the tested viruses. To the best of our knowledge, this is the first report on virus elimination from kiwifruit infected with multiple viruses based on conventional shoot tip culture and shoot tip cryotherapy.

Central venous catheter-related infection: does insertion site still matter? A French multicentric cohort study.

We aim to evaluate the association between central venous catheter (CVC) insertion site and microbiological CVC complications in a nationwide cohort. This study was conducted using the healthcare-associated infection surveillance cohort "REA-REZO" involving 193 intensive care units (ICUs). All CVC inserted and removed during the same ICU stay between January 1st 2018 and December 31st 2022 were eligible but only those whose tips were sent for microbiological analysis were included. Primary objective was to describe CVC insertion sites and subsequent catheter-related bloodstream infection (CRBSI). Out of 126,997 CVCs, 71,314 were not sent for tip culture, and only 55,663 CVCs were included, (30,548 in internal jugular [IJ], 14,423 in femoral and 10,692 in subclavian [SC] sites). The incidence of CRBSI was 0.7 [0.6-0.8] in the IJ site, 0.7 [0.6-0.9] in the femoral site, and 0.6 [0.4-0.7] CRBSI per 1000 CVC days in the SC site (p = 0.248). The multivariable Poisson regression model showed no differences of CRBSI incidence rates between the three insertion sites. Microorganisms observed in CRBSI were coagulase-negative Staphylococci (27.9%), Enterobacterales (27.5%), non-fermenting Gram-negative Bacilli (10.4%), Candida sp. (16.9%), and Staphylococcus aureus (16.9%). Low CRBSI incidence rates were reported. CRBSI incidences rates were similar in the three insertion sites. Uncertainty remains due to potential selection bias since many CVCs had to be excluded.

Clinical Features of Candida Catheter-related Bloodstream Infections and Persistent Infections Associated with Early Catheter Reinsertion: A 6-year Retrospective Study

Abstract Introduction: Catheter-related persistent Candida infections (CRPCI) may develop after Candida catheter-related bloodstream infections (CRBSI) due to colonization of the newly inserted catheter. However, the optimal timing for new catheter insertion remains controversial. The aim of this study was to determine the clinical features of CRBSI due to Candida species and CRPCI. This was a retrospective study conducted in a teaching hospital in Japan. Methods: We retrospectively collected clinical information on hospitalized patients diagnosed with Candida CRBSIs by catheter tip culture from 2015 to 2020. CRPCI was defined as the growth of the same Candida species from the tip culture of a newly inserted catheter after the onset of a Candida CRBSI. The Chi-squared and Fisher’s exact tests were used to compare differences between the case and control groups. Results: Sixty-three cases of Candida CRBSI were collected. Fifty-four (85.7%) received total parenteral nutrition. CRPCI developed in 12 (48%) patients of the 25 in whom cultures of newly inserted catheters were performed. Despite antifungal therapy in these patients, persistent fungemia incidence was significantly higher (50.0% vs. 9.1%, odds ratio = 10.0, P = 0.033). The mean number of days from removal of infected catheter to reinsertion was significantly shorter for patients with CRPCI (0.27 days vs. 3.08 days, P = 0.038). Conclusions: Total parenteral nutrition may be a major risk factor in the development of Candida CRBSI. CRPCI often leads to persistent fungemia. Early insertion of a new catheter after removal of an infected catheter may be a risk factor for CRPCI.

Effectiveness of Surgical Drains in Obese Patients Undergoing Lumbar Discectomy.

Background The placement of postoperative drains after spine surgery is a contentious issue, and its application has changed over time. Obesity itself is an independent risk factor for postoperative complications. Hematomas in the surgical wound are a complication that may necessitate revision surgery. Orthopaedic surgeons frequently use closed drainage in orthopaedic surgery to prevent the formation of a hematoma. It remains unclear whether drains reduce postoperative complications and improve clinical outcomes, especially in obese patients who are already at risk of such complications. Objectives To assess the incidence of surgical site infections (SSI) after lumbar discectomy in obese and morbidly obese patients with or without postoperative wound drainage and compare functional outcomes between both groups. Methodology A hospital-based retrospective study was conducted among 84 patients with obesity who underwent single-level lumbar discectomy at R. L. Jalappa Hospital and Research Centre, Kolar, India from May 2022 to April 2023. Drains were used for patients in Group A and avoided for patients in Group B. Results Postoperative C-reactive protein (CRP) levels in the non-drainage group were much higher than in the drainage group and were statistically significant. There was a statistically significant association found between body mass index (BMI) and postoperative SSI. In Group A, only three patients had SSI while in Group B, eight patients suffered from SSI. Conclusion Closed suction drains were shown to have a positive impact in reducing SSI in patients with obesity. Drain tip culture may be beneficial in detecting SSI at the earliest. Hence, we believe that closed suction drainage can be considered as a standard protocol in obese patients.

Bacterial Resistances and Sensibilities in a Tertiary Care Hospital in Romania-A Retrospective Analysis.

The increase in bacterial resistance is currently a global burden for the health care system. In order to evaluate the resistance rates of several bacteria from the most encountered cultures in clinical practice, we performed a retrospective analysis of all of the positive cultures from the year 2021 in a tertiary care hospital in Romania. Our analysis captured 3299 positive cultures. The median age of the patients was 62 years (IQR: 41-71 years old) with a slight predominance among females (53.1%). Overall, the most common cultures were urocultures, wound secretion cultures and blood cultures, and the most common identified bacteria were Escherichia coli, Staphylococcus aureus and Klebsiella spp. Positive cultures with the highest resistance rates were found in the bronchial aspirate cultures, catheter tip cultures, urocultures and blood cultures. Escherichia coli (n = 996) had the highest resistance to ampicillin (19.8%) and trimetoprim-sulfametoxazole (16.4%), while Staphylococcus aureus (n = 698) presented the highest resistance rates to clindamycin (27.4%) and oxaciline (19.7%). Klebsiella (n = 481) presented the highest resistance rates to piperaciline-tazobactam (25.2%) and ampicillin (20.4%), whereas Acinetobacter baumanii (n = 123) presented a resistance rate of more than 50% to carbapenems, gentamicin, ciprofloxacin and ceftazidime. The aim of our study was to identify bacterial resistance rates in order to provide updated clinical data to guide physicians in choosing the best empirical antibiotic treatment, especially in the west part of Romania.

Association between suction tip culture and surgical site infection in elective clean orthopedic lower limb surgeries

Background: Surgical site infections (SSIs) can be caused by various factors, including contamination of the surgical field. Perioperative cultures can be employed in clean orthopedic procedures to detect bacterial contamination that may occur during surgery. Aims and Objectives: The study aimed to evaluate the correlation between suction tip cultures and surgical wounds in clean orthopedic surgeries. Materials and Methods: A cross-sectional study was conducted at Yenepoya Medical College Hospital, Mangalore, Karnataka, with 250 patients in whom drain tips were sent for culture and followed up for 3 months to assess for SSI. Skin commensals from the nasal and groin samples were analyzed for the presence of bacteria. Results: A total of 250 patients meeting the inclusion and exclusion criteria were included. Thirty patients were positive for drain tip culture, and 12 (4.8%) patients had SSI during the 3rd month follow-up period, showing a statistically significant relationship between drain tip culture and SSIs (P=0.001). Skin commensals constituted 67% (nasal) and 100% in the groin of perioperative contaminants, accounting for 4.8% of SSIs. Conclusion: Suction drain tip culture and skin commensal analysis may be good predictors of SSIs. Intraoperative surgical site contaminants can be identified using perioperative cultures. Timely administration of suitable antibiotics and local wound care for perioperative contamination can help minimize the incidence of SSI.

Impact of the COVID-19 pandemic on the incidence and the epidemiology of catheter-related bloodstream infection two years later

IntroductionThe COVID-19 pandemic increased catheter-related bloodstream infections (C-RBSI), but its subsequent impact has not been adequately described. Our hospital has already depicted the effects of the COVID-19 pandemic in the first wave. However, we still do not know whether C-RBSI rates and aetiology are similar to those described before the COVID-19 pandemic. We aimed to evaluate the impact of the COVID-19 pandemic on the evolution of C-RBSI in a large tertiary teaching hospital two years later. Material and methodsWe prospectively collected all confirmed C-RBSI episodes in a clinical microbiology laboratory database by matching blood cultures and catheter tip cultures with the isolation of the same microorganism (s). We compared our C-RBSI incidence rates and aetiology from 2018 to 2023. C-RBSI was defined as bacteremia or fungemia in a patient with clinical manifestations of infection and no other apparent source except the catheter. ResultsDuring the study period, we collected 556 C-RBSI episodes. C-RBSI incidence rate per 1000 admissions each year was as follows: 2018: 2.2; 2019: 1.7; 2020: 3.29; 2021: 2.92; 2022: 2.69. and 2023: 2.01. Mainly, C-RBSI episodes occurring in critical care units each year were, respectively: 2018: 57 (54.8 %), 2019: 38 (45.2 %), 2020: 89 (63.6 %), 2021: 69 (60.5 %), 2022: 58 (50.9 %) and 2023 (61.4 %). The distribution of microorganisms showed an increase in Gram-negative episodes after the pandemic. ConclusionOur study shows an increase in the incidence rate of C-RBSI during the COVID-19 pandemic, with a discrete decrease after that. C-RBSI episodes were mainly caused by coagulase-negative Staphylococci but with a rise in Gram-negative bacilli.

Treatment of positive catheter tip culture without bloodstream infections in critically ill patients. A case-cohort study from the OUTCOMEREA network

PurposeThis study aimed to evaluate the impact on subsequent infections and mortality of an adequate antimicrobial therapy within 48 h after catheter removal in intensive care unit (ICU) patients with positive catheter tip culture.MethodsWe performed a retrospective analysis of prospectively collected data from 29 centers of the OUTCOMEREA network. We developed a propensity score (PS) for adequate antimicrobial treatment, based on expert opinion of 45 attending physicians. We conducted a 1:1 case-cohort study matched on the PS score of being adequately treated. A PS-matched subdistribution hazard model was used for detecting subsequent infections and a PS-matched Cox model was used to evaluate the impact of antibiotic therapy on mortality.ResultsWe included 427 patients with a catheter tip culture positive with potentially pathogenic microorganisms. We matched 150 patients with an adequate antimicrobial therapy with 150 controls. In the matched population, 30 (10%) subsequent infections were observed and 62 patients died within 30 days. Using subdistribution hazard models, the daily risk to develop subsequent infection up to Day-30 was similar between treated and non-treated groups (subdistribution hazard ratio [sHR] 1.08, 95% confidence interval [CI] 0.62–1.89, p = 0.78). Using Cox proportional hazard models, the 30-day mortality risk was similar between treated and non-treated groups (HR 0.89, 95% CI 0.45–1.74, p = 0.73).ConclusionsAntimicrobial therapy was not associated with decreased risk of subsequent infection or death in short-term catheter tip colonization in critically ill patients. Antibiotics may be unnecessary for positive catheter tip cultures.

Insertion site and risk of peripheral intravenous catheter colonization and/or local infection: a post hoc analysis of the CLEAN 3 study including more than 800 catheters

AimAlthough uncommon, infections associated with peripheral intravenous catheters (PIVCs) may be responsible for severe life-threatening complications and increase healthcare costs. Few data are available on the relationship between PIVC insertion site and risk of infectious complications.MethodsWe performed a post hoc analysis of the CLEAN 3 database, a randomized 2 × 2 factorial study comparing two skin disinfection procedures (2% chlorhexidine-alcohol or 5% povidone iodine-alcohol) and two types of medical devices (innovative or standard) in 989 adults patients requiring PIVC insertion before admission to a medical ward. Insertion sites were grouped into five areas: hand, wrist, forearm, cubital fossa and upper arm. We evaluated the risk of risk of PIVC colonization (i.e., tip culture eluate in broth showing at least one microorganism in a concentration of at least 1000 Colony Forming Units per mL) and/or local infection (i.e., organisms growing from purulent discharge at PIVC insertion site with no evidence of associated bloodstream infection), and the risk of positive PIVC tip culture (i.e., PIVC-tip culture eluate in broth showing at least one microorganism regardless of its amount) using multivariate Cox models.ResultsEight hundred twenty three PIVCs with known insertion site and sent to the laboratory for quantitative culture were included. After adjustment for confounding factors, PIVC insertion at the cubital fossa or wrist was associated with increased risk of PIVC colonization and/or local infection (HR [95% CI], 1.64 [0.92—2.93] and 2.11 [1.08—4.13]) and of positive PIVC tip culture (HR [95% CI], 1.49 [1.02—2.18] and 1.59 [0.98—2.59]).ConclusionPIVC insertion at the wrist or cubital fossa should be avoided whenever possible to reduce the risk of catheter colonization and/or local infection and of positive PIVC tip culture.

Time-Dependent Bacterial Contamination of a Surgical Suction Tip.

Background: No in vitro surgical study has evaluated the time-dependent contamination of surgical suction tips compared with controls. Our purpose was to determine the difference in suction tip bacterial contamination rates between suction-positive and suction-negative tips. Materials and Methods: A matched-pair analysis of the contamination of surgical suction tips over a six-hour period was performed in two clean operating rooms. One suction tip was connected to standard wall suction (suction-positive group), with a matched control tip not connected to wall suction (suction-negative group). At time zero and then at hourly intervals for six hours, the distal 3 cm of suction tips were removed, placed in nutrient broth for 48 hours, then plate cultured. One hundred tips were collected for each time interval. Results: Eighty-two of 700 (11.7%) suction tips had bacterial contamination. Sixty-three (18.0%) of 350 suction-positive tips were contaminated, with 19 (5.4%) of the 350 suction-negative tips contaminated (χ2 = 26.7, p < 0.001). Suction tip contamination was time-dependent with the first significant difference between groups occurring after two hours of continuous suction (χ2 = 4.0, p = 0.04). Contamination rate in the suction-positive group increased significantly after one hour compared with time-zero controls (χ2 = 7.1, p = 0.008). There was no significant difference in frequency of positive cultures over time in the suction-negative group compared with time-zero controls. Conclusions: This is the first controlled laboratory study suggesting a time-dependent increase in positive suction tip cultures. From our data, operating room staff should have an awareness that suction tips represent a potential source of bacterial concentration. We recommend that when not in use, suction tip valves be closed if this feature is available, that hosing be manipulated to cease suction when not needed, that suckers be disconnected from tubing, or that suckers be exchanged at frequent intervals. Doing so may reduce bacterial contamination on the suction tip.

Elimination of cherry virus A from Prunus domestica ‘Besztercei Bt. 2’ using in vitro techniques

Cherry virus A, a capillovirus, can infect different Prunus species and be present as a latent infection in orchards. CVA infection was detected in a Hungarian stock collection of Prunus domestica ‘Besztercei Bt. 2’. In our study, different in vitro virus elimination techniques (thermotherapy combined with shoot tip culture and chemotherapy alone or combined with thermotherapy) were used and compared for their efficiency in eliminating CVA from ‘Besztercei Bt. 2’ plum cultivar. Thermotherapy was carried out at 38/36°C (day/night) in a heat chamber followed by the excision of 1–2 mm long shoot tips for plant regeneration. As a chemotherapy agent, ribavirin or zidovudine was added to the multiplication medium at two different concentrations with or without two weeks of thermotherapy pretreatment. The plum shoots tolerated 14–18 days of heat treatment, 64% of the plants regenerated from shoot tips, and 75% of the tested regenerated plants were confirmed by RT‒PCR to be CVA-free. Ribavirin and zidovudine did not negatively affect the survival of the plum shoots at any applied concentrations. Zidovudine alone was not able to efficiently eradicate virus from the treated plantlets, but when zidovudine was combined with heat treatment, the number of CVA-positive plants decreased to 60%. In contrast, ribavirin alone was very efficient at eliminating CVA from all the tested plants when used at a concentration of 25 mg L− 1. To our knowledge, this is the first report of eliminating CVA from Prunus sp. via in vitro techniques.

Perioperative arterial catheterization: A prospective evaluation of ultrasound, infection, and patient-focused outcomes.

There is little information regarding complications of arterial catheterization in modern clinical care. We aimed to determine the incidence of abnormal duplex vascular ultrasound and catheter related infections following perioperative arterial catheterization. Patients requiring arterial catheterization for elective surgery were included and insertion details collected prospectively. Duplex ultrasound evaluation was performed 24 h after catheter removal. Symptomatic patients were identified by self-reported questionnaire. On Day 7, patients answered questions by telephone, related to the insertion site, pain, and function. Results of catheter tip and blood culture analyses were sought. Univariate associations of patient and surgical characteristics with abnormal ultrasound were assessed with p < 0.05 considered significant. Of 339 catheterizations, 105 (40%) had ultrasound evaluation. Catheters were indwelling for median (IQR, range) duration of 6.0 h (4.4-8.2, 1.8-28) with no catheter-related infections. There were 16 (15.2%, 95% CI 9.0%-23.6%) abnormal results, including 14 radial artery thromboses, one radial artery dissection, and one radial vein thrombosis. Those with abnormal ultrasound results were more likely to have had Arrow catheters inserted (68.8% vs 27%, p = 0.023) and more than one skin puncture (37.5% vs 26.8%, p = 0.031). Two of the 16 (12.5%) patients with abnormal ultrasound results reported new symptoms related to the hand compared with nine of the 88 (10.2%) with normal results (p = 0.1). No patients required urgent referral for management. Thrombosis was the most common abnormality and was usually asymptomatic. There were no infections, few post-operative symptoms, and minimal functional impairment following arterial catheterization.

Harnessing the potential of transverse thin cell layer culture for high-frequency micropropagation of Thai ginseng (Kaempferia parviflora Wall. Ex Baker)

In vitro plant propagation techniques play an important role in modern agriculture and horticulture, offering efficient methods for the accelerated multiplication of high-value plant species. Thin cell layer (TCL) culture technique has emerged as a promising approach for large-scale in vitro plantlets production. This study explores the potential of TCL culture as a cutting-edge strategy to enhance the efficiency of multiple shoots formation in Kaempferia parviflora. An attempt was also made to look into the synergistic effects of cytokinin and auxin [6-benzyladenine (BA) - indole-3-acetic acid (IAA)] during micropropagation. Shoot tip explants (from rhizome sprouts) were cultured onto Murashige and Skoog (MS) medium enriched with BA (2.0–8.0 mg/L) and IAA (0.2–0.8 mg/L) in combination where the highest shoot number (7.3 shoots/explant) and length (5.9 cm) was obtained in 8.0 mg/L BA and 0.8 mg/L IAA. Subsequently, the transverse thin cell layer (tTCL) culture system was successfully utilized whereby the shoot tip explants were individually sliced from tips at the meristem and cultured onto MS medium supplemented with BA (2.0–8.0 mg/L) and IAA (0.2–0.8 mg/L) in combination. The regenerated tTCLs exhibited the highest shoot multiplication (9.3 shoots/tTCL; 28 shoots/shoot tip) and length (5.3 cm) in 4.0 mg/L BA + 0.8 mg/L IAA, thus significantly increased number of plantlets were obtained from tTCL culture (953.0 plantlets) compared to shoot tip culture (527.7 plantlets) after six sub-culture cycles. The tTCL regenerants were successfully acclimatized (with 90% survival) and displayed active growth. Genetic fidelity assessment via inter-simple sequence repeats, conserved DNA-derived polymorphism, directed amplification of minisatellite-region DNA, and start codon targeted polymorphism marker systems suggested that a very low level (5.8%; 148 out of 2572 scorable bands) of polymorphism was detected whereas the ploidy level remained unchanged, confirmed by flow cytometry analysis. The implementation of tTCL culture, coupled with a controlled sub-culture regimen, holds significant potential for the efficient commercial-scale production of K. parviflora.

Endoscopic Ventricular Lavage in Pediatric Pyogenic Cerebral Ventriculitis Associated with Shunt: Outcomes and Technical Notes

Pyogenic cerebral ventriculitis (PCV) is a rare infectious entity characterized by a potent inflammatory reaction of the ventricular ependyma, which in most cases leads to death. We aim to present the technical note and protocol, based on our center's 10-year experience of the use of endoscopic ventricular lavage in pediatric patients with PCV and ventriculoperitoneal shunt (VPS). For this study, all pediatric patients (<16 years) with VP shunts and PCV who were treated with endoscopic ventricular lavage between January 2012 and January 2022 were included. 34 pediatric patients with ventriculitis were analyzed. The median age was 6 years, with 61.7% being male. Most consultations occurred on Day 2 of symptoms. Fever (38.2%) and altered consciousness (26.5%) were the most common initial symptoms. Early ventriculitis was observed in 67.7% of patients. Pathogen identification in the initial cerebrospinal fluid (CSF) sample was 70.6%, while samples from ventricular peritoneal shunt (VPS) yielded 23.53% and catheter culture 79.4%. Gram-positive bacteria, mainly S.epidermidis (44.1%), was the most commonly isolated agent. Endoscopic ventricular lavage was performed in 73.5% on the second or third day. Reinfection occurred in 23.5%, and 26.5% of patients died. Concordance analysis showed 85.3% agreement between LP and catheter tip samples. Functionality improved, with 55.88% achieving a Lansky score of 90. Early ventriculitis was associated with better Lansky scores. Endoscopic ventricular lavage can be a useful tool in the management of PCV in cases with VP shunts. Our study suggests a higher chance of isolating an infection-causing germ in the catheter tip culture specimen compared to the cerebrospinal fluid (CSF) culture. However, future studies with a larger number of patients, or multicentric studies are required for further analysis.

Optimization of plant growth regulators for in vitro mass propagation of Philodendron cv. Birkin through shoot tip culture

Optimization of plant growth regulators for in vitro mass propagation of Philodendron cv. Birkin through shoot tip culture

Application of Biotechniques for In Vitro Virus and Viroid Elimination in Pome Fruit Crops.

Sustainable production of pome fruit crops is dependent upon having virus-free planting materials. The production and distribution of plants derived from virus- and viroid-negative sources is necessary not only to control pome fruit viral diseases but also for sustainable breeding activities, as well as the safe movement of plant materials across borders. With variable success rates, different in vitro-based techniques, including shoot tip culture, micrografting, thermotherapy, chemotherapy, and shoot tip cryotherapy, have been employed to eliminate viruses from pome fruits. Higher pathogen eradication efficiencies have been achieved by combining two or more of these techniques. An accurate diagnosis that confirms complete viral elimination is crucial for developing effective management strategies. In recent years, considerable efforts have resulted in new reliable and efficient virus detection methods. This comprehensive review documents the development and recent advances in biotechnological methods that produce healthy pome fruit plants. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.