Prospective, randomized study comparing two different regimens of split-dose polyethylene glycol and their effect on endoscopic outcomes.

BACKGROUND: Different split regimens of polyethylene glycol are routinely used and no guidelines are available to select an optimal protocol of ingestion. This study aims to compare the efficacy and side effect profile of two different regimens of polyethylene glycol bowel preparation solution: PEG (3 + 1) vs. PEG (2 + 2). METHODS: 240 patients above the age of 18 years were included in the study between June 1st and November 31st, 2023. Patients were randomly assigned either to Group A, consisting of 115 patients receiving a 3 L of PEG the night before the colonoscopy, and 1 L the same morning of the procedure. Or to group B, where 125 patients ingested 2 L the night before the procedure, and the remaining 2 L the same morning. The cleansing efficacy was evaluated by the attending endoscopist using the Boston Bowel Preparation Scale, through a score assigned for each segment of the colon (0-3). Side effects, tolerability, and willingness to retake the same preparation were listed by an independent investigator using a questionnaire administered before the procedure. RESULTS: A higher percentage of patients had gastric fullness with the 3 + 1 vs. 2 + 2 preparation (58.3% vs. 31.2%; p <.001). A higher Boston bowel preparation score was seen in patients who took the 2 + 2 vs. 3 + 1 preparation (7.87 vs. 7.23). Using the 2 + 2 preparation was significantly associated with higher Boston bowel preparation scores vs. the 3 + 1 preparation (OR = 1.37, p =.001, 95% CI 1.14, 1.64). After adjustment over other variables (age, gender, comorbidities, previous abdominal surgeries, presence of adenoma, and time between last dose and colonoscopy), results remained the same (aOR = 1.34, p =.003, 95% CI 1.10, 1.62). CONCLUSION: While both (2 + 2) and (3 + 1) regimens of polyethylene glycol are a good choice for a successful colonoscopy, we recommend the use of (2 + 2) regimen for its superior efficacy in bowel cleansing.

Successful use of split-dose intravenous daratumumab in a multiple myeloma patient after a first-dose life-threatening infusion-related reaction.

INTRODUCTION: Daratumumab is a humanized IgG1 kappa monoclonal antibody directed against CD38 used to treat myeloma. The recommended dose of daratumumab is 16 mg/kg, with no lower or upper threshold. Here, we present the first split-dose daratumumab infusion experience in a myeloma patient with morbid obesity in whom daratumumab was interrupted because of grade 3 infusion-related reaction. CASE REPORT: A female myeloma patient with morbid obesity received a combination of chemotherapy with daratumumab because of disease relapse. The calculated dose for the first intravenous daratumumab infusion was 1840 mg/day based on the weight of the patient, which was measured as 115 kilograms. Daratumumab infusion was initiated as appropriate but needed to be stopped because of a severe sudden presentation of shortness of breath and hypoxemia. MANAGEMENT AND OUTCOME: After daratumumab was stopped, premedication was repeated, and oxygen, intravenous and inhaler steroids, inhaler ß2 agonists and intravenous diphenhydramine were given in repeated doses. She was monitored and followed up in the emergency critical care unit. Daratumumab treatment with a split-dose schedule was planned after she fully recovered from all signs and symptoms. The total dose was divided into two doses and was given without any complications on two consecutive days. After that, she was also able to tolerate once a week 1840 mg of daratumumab in a single day. DISCUSSION: There is a paucity of data regarding the best practice for instituting intravenous daratumumab in patients with morbid obesity regarding the infusion rate and duration, optimal dosing, and ideal way to cope with infusion-related reactions. Our case suggests a potential role for a split-dose schedule for patients with obesity and potential dose reductions and infusion-related reactions.

Split-Dose Administration Enhances Immune Responses Elicited by a mRNA/Lipid Nanoparticle Vaccine Expressing Respiratory Syncytial Virus F Protein.

mRNA vaccines have recently received significant attention due to their role in combating the SARS-CoV-2 pandemic. As a platform, mRNA vaccines have been shown to elicit strong humoral and cellular immune responses with acceptable safety profiles for prophylactic use. Despite their potential, industrial challenges have limited realization of the vaccine platform on a global scale. Critical among these challenges are supply chain considerations, including mRNA production, cost of goods, and vaccine frozen-chain distribution. Here, we assess the delivery of lipid nanoparticle-encapsulated mRNA (mRNA/LNP) vaccines using a split-dose immunization regimen as an approach to develop mRNA dose-sparing vaccine regimens with potential to mitigate mRNA supply chain challenges. Our data demonstrate that immunization by a mRNA/LNP vaccine encoding respiratory syncytial virus pre-F (RSV pre-F) over a 9 day period elicits comparable or superior magnitude of antibodies when compared to traditional bolus immunization of the vaccine. The split-dose immunization regimens evaluated in our studies were designed to mimic reported drug or antigen release profiles from microneedle patches, highlighting the potential benefit of pairing mRNA vaccines with patch-based delivery technologies to enable sustained release and solid-state stabilization. Overall, our findings provide a proof of concept to support further investigations into the development of sustained delivery approaches for mRNA/LNP vaccines.

Randomized clinical trial evaluating three low-volume preparations for colonoscopy in outpatients with Inflammatory Bowel Disease: the EII-PREP trial.

BACKGROUND: Data regarding bowel preparation in patients with Inflammatory Bowel Disease (IBD) are scarce. AIM: To compare efficacy, safety, and tolerability of low-volume preparations in patients with IBD. METHODS: Single-center, randomized, prescriber, and colonoscopist-blinded clinical trial. IBD outpatients undergoing colonoscopy were randomized 1:1:1 to receive 1 Liter-polyethylene glycol-ascorbate (1L-PEG), 2 Liters-PEG, or sodium picosulfate (SP). The primary endpoint was percentage of quality cleansing assessed via the Boston Bowel Preparation Scale (BBPS ≥6, segments ≥2). Secondary endpoints were total high quality cleansing (BBPS 8 or 9), high-quality segmental BBPS (≥2), and patients' tolerability, symptoms, and satisfaction, assessed by questionnaires. Safety was monitored by adverse event reporting, laboratory evaluation at colonoscopy, and telephonic follow-up. RESULTS: Ninety-two patients were included (33 1L-PEG, 28 2L-PEG, and 31 SP). No significant differences between preparations were observed in quality or high-quality total BBPS or high-quality segmental BBPS. Complete intake of the solution was higher for SP (p = 0.006) and lower for 1L-PEG (p = 0.02) compared to 2L-PEG intake (p = 0.55). Clinically irrelevant hyponatremia was higher in the SP group (p < 0.0001). SP instructions were easier to understand from patient's point of view (p = 0.01). Willingness to retake was higher with SP (p < 0.0001) and less for 1L-PEG (p < 0.0001). No serious adverse events were reported. CONCLUSIONS: We observed no differences in efficacy between low-volume preparations in patients with IBD. Complete intake was higher for SP and lower for 1L-PEG. SP and 2L-PEG instructions were better understood and graded, and SP was more likely to be retaken. Willingness to retake was lower for 1L-PEG. No serious adverse events were reported. SUMMARY: No differences in terms of efficacy were regarded in this clinical trial comparing low-volume preparations for colonoscopy in patients with IBD: however, Sodium Pisoculfate is better tolerated and accepted from patient's point of view. No serious adverse events were reported.

Single vs split dose of prednisolone in the treatment of relapses of childhood nephrotic syndrome.

Nephrotic syndrome is the commonest glomerular disease in childhood. It usually follows a relapsing and remitting course. Corticosteroids are the mainstay of treatment for both the first episode and subsequent relapses. This study was conducted at a single centre to compare the clinical response to a single dose vs. split dose of prednisolone in the treatment of relapses of childhood nephrotic syndrome. Children between the ages of 1 and 14 years admitted with a relapse of idiopathic steroid sensitive nephrotic syndrome from August 2019 to February 2020 were considered for recruitment. A block randomization method based on age was used for allocation. Patients randomised to group A received oral prednisolone at 60 mg/m2 as a single morning dose, while those randomised to group B received the same total dose as two divided doses, of which 2/3 was given in the morning and the rest in the evening. Treatment was continued until remission was achieved following which all patients were switched to alternate day prednisolone. An independent sample t test was used to compare the two groups. One hundred and four episodes of relapse occurring in 96 children were included of which 49 were treated with prednisolone as a split dose and 55 were treated with a single dose of prednisolone. The mean duration to achieve remission for the split-dose group was 8.02 days (SD 1.58) while it was 9.74 days (SD 3.72) for the single-dose group. This difference was statistically highly significant (t(102) = 3.004; p = 0.001; CI 0.58 to 2.86). There was no difference in the adverse events profile of the two groups.  Conclusion: The use of prednisolone as a split dose results in a shorter duration to achieve remission when compared to a single morning dose, resulting in a lower cumulative dose of prednisolone to achieve remission. What is Known: • Corticosteroids are the mainstay of treatment for childhood nephrotic syndrome. • Corticosteroids are given as a single dose in the morning to minimise adrenocortical suppression. What is New: • A more rapid attainment of remission can be achieved with a split dose of corticosteroids.

Split-dose versus day-before regimen of sodium picosulfate plus magnesium citrate for bowel cleansing before colonoscopy in children: Randomized controlled trial.

OBJECTIVES: Polyethylene glycol (PEG) split-dose regimen is recommended as the option of choice for colon preparation before colonoscopy in children and adults. Sodium picosulfate plus magnesium citrate (SPMC) is equally effective but better tolerated than PEG for bowel preparation before colonoscopy in children. The aim of this study was to assess the superiority of SPMC split-dose regimen compared with SPMC day-before regimen for bowel cleansing before colonoscopy in children. METHODS: This was a multicenter, randomized, single-blind study. Pediatric inpatients undergoing colonoscopy received SPMC either in the day-before dosing or in split dosing. Overall bowel cleansing was assessed using the Boston Bowel Preparation Scale (BBPS) and was rated as successful when BBPS was ≥6. Patient tolerability, acceptability, and compliance were recorded. RESULTS: The rate of successful cleansing level was significantly higher in the split-dose group than in the day-before group (P < 0.001). The BBPS scores were significantly higher in the split-dose group than in the day-before group for the whole colon (P < 0.001), the right colon (P < 0.001) and transverse colon (P < 0.001). Patient acceptability was better in the split-dose group (P = 0.0003; P = 0.005). The percentage of children needing nasogastric tube placement was better in the split-dose group (P = 0.007). CONCLUSIONS: The split-dose regimen of SPMC was superior to the day-before regimen in terms of successful colon cleansing and acceptability.

Is split-dose better than single-dose? Results of Turkish Stem Cell Coordination Center (TURKOK) donors in the era of rising biosimilar G-CSF.

BACKGROUND: Turkish Stem Cell Coordination Center (TURKOK) carries out the procurement process of unrelated allogeneic hematopoietic stem cells in Turkey. This study aims to compare the efficacy of both once-daily and divided-dose G-CSF administration and the original and biosimilar G-CSF use and the frequency and severity of adverse events in TURKOK donors. METHOD: The study was conducted retrospectively with 142 healthy TURKOK donors. For PBSC mobilization, two different subcutaneous G-CSF programs were used as 10 µ/kg/day single-dose and 5 µ/kg/12 h. Neupogen (Amgen, Puerto Rico) and Tevagrastim (Teva, Kfar Saba, Israel) were used as G-CSF. All donors started apheresis on the fifth day, and all side effects were recorded during the procedure. RESULTS: Stem cell yield was similar between single-dose and divided-doses based on donor weight, favoring the split-dose based on recipient weight (P = .506 and P = .023, respectively). Both G-CSF posologies were comparable if the target CD34+ cell yield was ≥4 × 106 /kg. CD34+ cell yield was equivalent when evaluated against recipient weight, significantly favoring Tevagrastim vs Neupogen by donor weight (P = .740 and P = .021, respectively). Side effects, duration of pain, and need for analgesia favor Tevagratim over Neupogen. CONCLUSION: Split-dose may be recommended for cases where the need for large numbers of CD34+ cells to be harvested is anticipated due to significant cell yield relative to recipient weight. However, sufficient hematopoietic stem cells can be collected with both posology. Tevagrastim is non-inferiority effective to Neupogen. Side effects during administration are both low-grade and temporary.

The Impact of Patient Education Level on Split-Dose Colonoscopy Bowel Preparation for CRC Prevention.

INTRODUCTION: AGA guidelines emphasize split-dose bowel preparation (BP) to ensure high-quality colonoscopy for the prevention of colorectal cancer (CRC). Split dose results in higher-quality preparation, but understanding instructions might be more difficult. Lower education levels may negatively influence BP quality. The confounding role of education level on BP quality was investigated. METHODS: This was a cross-sectional study of 60 patients given split-dose BP. Patients consented and were asked three Likert scale questions based on BP instructions before the procedure. Compliance was self-reported. BP adequacy and the number of adenomas were recorded. BP was characterized as adequate (excellent, good) or inadequate (fair, poor). Data was analyzed with chi-square, odds ratio, Mann-Whitney, and regression analysis. RESULTS: Thirty-one (52%) patients were high school graduates, 21 (38%) completed some college, and 6 (10%) were college graduates. College-educated patients had adequate BP (72%) more often than high school graduates (51%) (p = 0.02). Adenoma findings were not significantly different. The Likert scale mean ranks for patient understanding and reviewing of instructions were comparable between the two groups. Patient rating of scheduler explanations of the importance of following instructions was significantly better in the college group (mean ranks 2.59 and 1.83, respectively; p = 0.018). DISCUSSION: Patient education level significantly affected the success of BP. Split BP can be more complex to comprehend, and instructions should consider patient education level. Specific intervention programs should be implemented to advise patients with less education that poor preparation may result in missed advanced neoplasias and subsequent procedures.

Kinetics of cytokine mRNA and protein expression by plastic adherent cells in the thymus after split-dose irradiation.

Whole body irradiation causes significant apoptosis in various tissues such as the thymus. If apoptotic cells outnumber the phagocytic capacity of macrophages, apoptosis becomes secondary necrosis, inducing inflammatory cytokine expression in macrophages. Radiation also induces thymic lymphomas in C57BL/6 mice after four consecutive irradiations with 1.6 Gy X-rays with nearly 100% incidence. Since cancer development is modulated by a microenvironment involving macrophages, we examined the kinetics of thymocyte number and plastic adherent cell number in the thymus as well as cytokine mRNA expression by plastic adherent cells in the thymus after split-dose irradiation. Upon split-dose irradiation, thymocyte number changed dramatically, whereas plastic adherent cell number did not. Among cytokine mRNAs tested, IL-1ß, IL-11 and IL-12p40 mRNAs were up regulated 2 days after the 1st and 2nd, 3rd and 4th, and 2nd and 3rd irradiations, respectively. On the other hand, TNF-α mRNA was up regulated 2 days after the 3rd irradiation and 2 weeks after the 4th irradiation. The level of IL-11 protein was also increased 2 days after 3rd and 4th irradiations. These results suggest that, upon split-dose irradiation, macrophages in the thymus produce various cytokines in a time-dependent manner, thereby contributing to induction of thymic lymphomas.

Comparison of Small Versus Large Volume Split Dose Preparation for Colonoscopy: A Study of Colonoscopy Outcomes.

BACKGROUND: Split dose bowel preparations (SDP) have superior outcomes for colonoscopy as compared to evening before regimens. However, the association of the actual volume of the SDP to colonoscopy outcome measures has not been well studied. AIMS: Compare adenoma detection rate (ADR), sessile serrated polyp detection rate (SDR), mean bowel cleanse score, and predictors of inadequate exams between small volume SDP and large volume SDP. METHODS: We have conducted a retrospective study in patients undergoing colonoscopy with small volume SDP versus large volume SDP between July 2014 and December 2014. Basic demographics (age, gender and BMI) along with clinical co-morbidities were recorded. Quality of the bowel preparation, ADR and SDR was compared between these groups. Univariate and multivariable logistic regressions were used to assess the determinants of inadequate exams in each group. RESULTS: 1573 patients with split dose preparation were included in this retrospective study. 58.4% (920/1573) patients took small volume SDP. There was no difference in ADR (37.9 vs. 38.8%, p = 0.2); however, SDR was higher for small volume SDP compared to large volume SDP (11.9 vs. 7.9% p = 0.005). There was no difference in the rate of inadequate exams between the two groups (p = 0.7). A history of diabetes and constipation was associated with inadequate exams only in the small volume SDP. CONCLUSIONS: SDR was higher in small volume SDP. There was no difference in rate of inadequate exams between the two groups. A history of diabetes and constipation was associated with inadequate exams only in patients with the small volume SDP.

Split-Dose Preparations Are Superior to Day-Before Bowel Cleansing Regimens: A Meta-analysis.

BACKGROUND & AIMS: There are different regimens of preparing the colon for colonoscopy, including polyethylene glycol (PEG), sodium phosphate, picosulfate, or oral sulfate solutions. We performed a meta-analysis to determine the efficacy of split-dose vs other colon preparation regimens, the optimal products for use, and the most effective preparation volumes. METHODS: We performed systematic searches of MEDLINE, EMBASE, Scopus, CENTRAL, and ISI Web of knowledge databases, from January 1980 to March 2014, for published results from randomized trials that assessed split-dose regimens vs day-before colonoscopy preparation. We excluded studies that included pediatric or hospitalized patients, or patients with inflammatory bowel disease. The primary outcome was efficacy of bowel cleansing. Secondary outcomes included side effects or complications, outcomes of procedures, patients' willingness to repeat the procedure, and the amount of time required for patients to resume daily activities. RESULTS: We identified 47 trials that fulfilled our inclusion criteria (n = 13,487 patients). Split-dose preparations provided significantly better colon cleansing than day-before preparations (odds ratio [OR], 2.51; 95% confidence interval, 1.86-3.39), as well as day-before preparations with PEG (OR, 2.60; 95% confidence interval, 1.46-4.63), sodium phosphate (OR, 9.34; 95% confidence interval, 2.12-41.11), or picosulfate (OR, 3.54; 95% confidence interval, 1.95-6.45). PEG split-dose preparations of 3 L or more yielded greater bowel cleanliness than lower-volume split-dose regimens (OR, 1.89; 95% confidence interval, 1.01-3.46), but only in intention-to-treat analysis. A higher proportion of patients were willing to repeat split-dose vs day-before cleansing (OR, 1.90; 95% confidence interval, 1.05-3.46), and low-volume split-dose preparations vs high-volume split-dose preparation (OR, 4.95; 95% confidence interval, 2.21-11.10). There were no differences between preparations in other secondary outcome measures. However, there was variation among studies in definitions and main and secondary outcomes. CONCLUSIONS: Based on meta-analysis, split-dose regimens increase the quality of colon cleansing and are preferred by patients compared with day-before preparations. Additional research is required to evaluate oral sulfate solution-based and PEG low-volume regimens further.

Split Dose of Prednisolone in the Treatment for Erythema Nodosum Leprosum: A Case Series.

Background Erythema nodosum leprosum (ENL) is an immune complex-mediated reaction that clinically presents as tender erythematous evanescent nodules, mostly associated with systemic symptoms. Oral prednisolone is the drug of choice, with doses ranging from 0.5 to 1 mg/kg. Some cases may develop new lesions and systemic symptoms despite 1 mg/kg prednisolone, and in ideal practice, physicians escalate the prednisolone dose for immediate arrest of inflammation to prevent complications. However, a high dose of prednisolone has more side effects in the long term and causes more immunosuppression. Methods In cases of ENL, those not responding to a conventional once-daily regimen were given a split dose of oral prednisolone instead of increasing the dose. They were followed up for response, and serum cortisol was measured to see for hypothalamic-pituitary-adrenal (HPA) axis suppression. Results Eight cases of ENL (three nodular, three necrotic, one pustular, and one nodulcerative) had a dramatic response to split-dose therapy without any relapse and HPA axis suppression. Conclusion A split-dosing regimen can be a good treatment option in ENL with better control, less steroid dependency, and a lower relapse rate.

Gut microbiota in children with split-dose bowel preparations revealed by metagenomics.

Objective: Split-dose polyethylene glycol (PEG) is routinely used for bowel preparation before colonoscopy. This study aimed to investigate the composition of gut microbiota and its functions in pediatric patients undergoing split-dose PEG bowel preparation for colonoscopy to understand the stability and resilience of gut microbiota. Material and methods: From September to December 2021, 19 pediatric patients were enrolled at Shenzhen Children's Hospital and 76 samples (4 time points) were analyzed using metagenomics. Time points included Time_1 (one day before bowel preparation), Time_2 (one day after colonoscopy), Time_3 (two weeks after bowel preparation), and Time_4 (four weeks after bowel preparation). Result: Alpha diversity comparison at both the species and gene levels showed a decrease in community richness after colonoscopy, with little statistical significance. However, the Shannon diversity index significantly decreased (P<0.05) and gradually returned to pre-preparation levels at two weeks after bowel preparation. The genus level analysis showed six genera (Eubacterium, Escherichia, Intertinibacter, Veillonella, Ruminococcaceae unclassified, and Coprobacillus) significantly different across the four time periods. Additionally, at the species level, the abundance of Escherichia coli, Bacteroides fragilis, and Veillonella parvula significantly increased at one day after colonoscopy before gradually decreasing at two weeks after bowel preparation. In contrast, the abundance of Intertinibacter bartlettii decreased at one day after colonoscopy but then recovered at two weeks after bowel preparation, reaching the preoperative level at four weeks after bowel preparation. Furthermore, five functional pathways (base excision repair, biosynthesis of ansamycins, biosynthesis of siderophore group nonribosomal peptide, flavonoid biosynthesis, and biosynthesis of type II polyketide products) were significantly different across the four time periods, with recovery at two weeks after bowel preparation and reaching preoperative levels at four weeks after bowel preparation. Conclusions: Gut microbiota at the genus level, species level, and functional pathways are impacted in pediatric patients undergoing split-dose PEG bowel preparation and colonoscopy, with recovery two weeks following bowel preparation. However, the phylum level was not impacted. Modifications in gut microbiota composition and function may be investigated in future studies of bowel preparation. This study highlights the stability and resilience of gut microbiota among pediatric patients during bowel preparation.

Efficacy of cisplatin plus vinorelbine adjuvant chemotherapy with split-dose administration of cisplatin after complete resection of stage II-IIIA non-small cell lung cancer.

Although co-administration of cisplatin (CDDP) and vinorelbine (VNR) has been established as a standard of care adjuvant chemotherapy for non-small cell lung cancer (NSCLC), there is a lack of clinical data on its safety and efficacy in Japanese patients receiving split-dose administration of CDDP. The present study analyzed patients who received CDDP + VNR with split-dose administration of CDDP after undergoing complete resection of NSCLC. Patients received four courses of CDDP (40 mg/m2) and VNR (25 mg/m2) on days 1 and 8, every 3 weeks. There were 27 male and 13 female patients; the mean age was 65 years (range 38-78 years), the postoperative disease staging distribution was IIA/IIB/IIIA: 14/8/18 patients, and histological distribution was adenocarcinoma/squamous cell carcinoma/others: 24/12/4 patients, respectively. Of the 40 patients, 28 (70%) completed the four courses of treatment. The mean total dose administered was 279 mg/m2 CDDP (87.2%) and 172 mg/m2 VNR (86%). The major adverse events included Grade (G) 3 or higher neutropenia (80%), G3 phlebitis (5%) and vomiting (2.5%). There was no G2 or higher serum creatinine level elevation, G3 or higher anorexia and nausea, or any treatment-related deaths. The overall completion rate of four courses was 70 and 62.5% for patients aged 70 years and older, whereas the overall percentage of patients that could complete three or more courses was 85 and 87.5% for patients aged 70 years and older. The relapse-free survival rate was 60% at 3 years and 57.5% at 5 years. Overall survival rate was 80% at 3 years and 60% at 5 years. The present study demonstrated the sufficient tolerability, safety and efficacy of combined CDDP + VNR adjuvant chemotherapy with split-dose administration of CDDP, with a low risk of gastrointestinal toxicities or nephrotoxicity.

Effectiveness of Dynamic Contrast Enhanced MRI with a Split Dose of Gadoterate Meglumine for Detection of Prostate Cancer.

RATIONALE AND OBJECTIVES: To evaluate whether dynamic contrast enhanced (DCE) MRI with a split injection of 30% followed by 70% of a standard dose (30PSD and 70PSD) of gadoterate meglumine (DOTAREM) can improve diagnosis of prostate cancer (PCa). MATERIALS AND METHODS: MRI for twenty patients was performed on a Philips Ingenia 3T scanner without an endorectal coil followed by subsequent radical prostatectomy. DCE 3D T1-FFE data were acquired with injection of 0.03 mmol/kg followed after 2 minutes by 0.07 mmol/kg of DOTAREM. Regions-of-interest on histologically verified PCa and normal tissue in different prostate zones and the iliac artery were drawn. Average signal intensity as function of time was calculated for each ROI and fitted by using the signal intensity form of the Tofts (SI-Tofts) model to extract physiological parameters (Ktrans and ve). In addition, the scaled arterial input function (AIF) obtained from 30PSD data was used to analyze 70PSD data. RESULTS: The AIF obtained from 30PSD data showed both first and second passes clearly and had much higher peak magnitude than AIFs from 70PSD data. Ktrans was significantly (p < 0.05) larger in PCa than in normal tissue in peripheral zone (PZ) and central zone (CZ) for both 70PSD and 70PSD data analyzed with a scaled AIF. Ktrans in cancer overlapped with that of normal tissue in the transition zone (TZ). There was no statistical difference in ve between cancer and normal tissue. Receiver operating characteristic analysis showed that use of the AIF from 30PSD data to analyze 70PSD data increased the diagnostic efficacy of Ktrans in the PZ and CZ. CONCLUSION: The split dose protocol for injection of Dotarem increased diagnostic accuracy of quantitative analysis with the SI-Tofts model.

Comparison of cisplatin-induced nephrotoxicity between single-dose and split-dose administration to rats.

To prevent cisplatin (CDDP)-induced nephrotoxicity, co-treatment with massive hydration is essential for its clinical use. However, some patients are ineligible for this treatment. For such patients, a split dose of CDDP has been suggested as an alternative strategy. This study aimed to evaluate the nephrotoxicity of a split dose of CDDP by direct comparison with the conventional single dose of CDDP in rats. Rats were allocated to single- or split-dose groups. In the single-dose group, rats received the total dose of CDDP (from 0 to 7.5 mg/kg) with a single injection, whereas the same total dose of CDDP was split equally across five doses in the corresponding split-dose group. Blood samples were taken until day 21 after the first CDDP injection to monitor the plasma creatinine (Cr) concentration as an index of nephrotoxicity. CDDP-induced nephrotoxicities from day 1-10 and from day 15-21 were defined as acute kidney injury (AKI) and subchronic kidney injury (sCKI), respectively. The toxicity of CDDP-induced AKI in the split-dose group was found to be significantly lower than that in the single-dose group at any given total dose level. At a total dose of 7.5 mg/kg, a decrease of approximately 90% in AKI was found in the split-dose group, while the extent of attenuation of CDDP-induced sCKI in this group was approximately 30%. Our results provide evidence that a split-dose regimen could be an alternative strategy for CDDP-ineligible patients; however, the optimal regimen needs to be determined in future studies.

Same-day single-dose vs large-volume split-dose regimens of polyethylene glycol for bowel preparation: A systematic review and meta-analysis.

BACKGROUND: Split-dose regimens (SpDs) of 4 L of polyethylene glycol (PEG) have been established as the "gold standard" for bowel preparation; however, its use is limited by the large volumes of fluids required and sleep disturbance associated with night doses. Meanwhile, the same-day single-dose regimens (SSDs) of PEG has been recommended as an alternative; however, its superiority compared to other regimens is a matter of debate. AIM: To compare the efficacy and tolerability between SSDs and large-volume SpDs PEG for bowel preparation. METHODS: We searched MEDLINE/PubMed, the Cochrane Library, RCA, EMBASE and Science Citation Index Expanded for randomized trials comparing (2 L/4 L) SSDs to large-volume (4 L/3 L) SpDs PEG-based regimens, regardless of adjuvant laxative use. The pooled analysis of relative risk ratio and mean difference was calculated for bowel cleanliness, sleep disturbance, willingness to repeat the procedure using the same preparation and adverse effects. A random effects model or fixed-effects model was chosen based on heterogeneity analysis among studies. RESULTS: A total of 18 studies were included. There was no statistically significant difference of adequate bowel preparation (relative risk = 0.97; 95%CI: 0.92-1.02) (14 trials), right colon Boston Bowel Preparation Scale (mean difference = 0.00; 95%CI: -0.04, 0.03) (9 trials) and right colon Ottawa Bowel Preparation Scale (mean difference = 0.04; 95%CI: -0.27, 0.34) (5 trials) between (2 L/4 L) SSDs and large-volume (4 L/3 L) SpDs, regardless of adjuvant laxative use. The pooled analysis favored the use of SSDs with less sleep disturbance (relative risk = 0.52; 95%CI: 0.40, 0.68) and lower incidence of abdominal pain (relative risk = 0.75; 95%CI: 0.62, 0.90). During subgroup analysis, patients that received low-volume (2 L) SSDs showed more willingness to repeat the procedure using the same preparation than SpDs (P < 0.05). No significant difference in adverse effects, including nausea, vomiting and bloating, was found between the two arms (P > 0.05). CONCLUSION: Regardless of adjuvant laxative use, the (2 L/4 L) SSD PEG-based arm was considered equal or better than the large-volume (≥ 3 L) SpDs PEG regimen in terms of bowel cleanliness and tolerability. Patients that received low-volume (2 L) SSDs showed more willingness to repeat the procedure using the same preparation due to the low-volume fluid requirement and less sleep disturbance.

Determinants of symptom burden related to bowel preparation for colonoscopy.

BACKGROUND: Symptoms developing during bowel preparation are major concerns among subjects who refuse the procedure. AIMS: We aimed to explore the determinants of symptoms occurring during preparation among patients undergoing elective colonoscopy. METHODS: This is a prospective multicenter study conducted in 10 Italian hospitals. A multidimensional approach collecting socio-demographic, clinical, psychological and occupational information before colonoscopy through validated instruments was used. Outcome was a four-category cumulative score based on symptoms occurring during preparation, according to the Mayo Clinic Bowel Prep Tolerability Questionnaire, weighted by intensity. Missing values were addressed through multiple imputation. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through multivariate logistic regression models. RESULTS: 1137 subjects were enrolled. Severe symptoms were associated with female sex (OR=3.64, 95%CI 1.94-6.83), heavier working hours (OR=1.13, 95% CI=1.01-1.25), previous gastrointestinal symptoms (OR=7.81, 95% CI 2.36-25.8 for high score), somatic symptoms (OR=2.19, 95% CI=1.06-4.49 for multiple symptoms), day-before regimen (OR=2.71, 95%CI 1.28-5.73). On the other hand, age ≥60 years (OR=0.10, 95% CI 0.02-0.44) and good mood (p=0.042) were protective factors. A high-risk profile was identified, including women with low mood and somatic symptoms (OR=15.5, 95%CI 4.56-52.7). CONCLUSIONS: We identified previously unreported determinants of symptoms burdening bowel preparation and identified a particularly vulnerable phenotype. Symptoms during preparation especially impact heavier working activity.

Radiation responses of cancer and normal cells to split dose fractions with uniform and grid fields: increasing the therapeutic ratio.

PURPOSE: Radiation treatment of cancer is usually delivered in a prescribed sequence of dose fractions within which the dependence of dose on time is determined by the treatment plan. New techniques, such as stereotactic body radiation therapy (SBRT) and image guided radiation therapy (IGRT) have been introduced with the motivation of improving therapeutic outcomes, with the consequence that the time dependence of the dose within a fraction is modified. Here, we test whether an increased toxicity to cancer cells arises when a radiation treatment fraction is delivered in two equal parts, allowing time for the expression of factors, for example, RONS and cytokines, in response to the first dose which may sensitize cells to the second dose. A medium time delay between 15 and 60 minutes is proposed to allow factors to be expressed before repair takes place. A grid field is used to enhance diffusion of the factors. MATERIALS AND METHODS: The cell lines used in the study were two prostate cancers (LNCaP and DU 145), a normal prostate (PNT1A), a non-small cell lung cancer (NCI-H460), and a glioma (Hs 683). Uniform or spatially modulated grid fields, delivering the same mean dose, were used. The results for the clonogenic survival fractions were grouped into a 'short' delay (under 10 minutes) and a 'medium' delay (between 15 and 60 minutes). RESULTS: The medium delay with a grid field yielded a significant increase in toxicity for the four cancer cell lines. The medium delay with a uniform field gave a significant increase in toxicity for the two prostate cancer cell lines. A highly significant increase was found in the therapeutic ratio, defined as the ratio of the survival of prostate normal to prostate cancer cells. CONCLUSIONS: The findings show that the intra-fractional dose schedule with medium time delay offers an opportunity to increase the toxicity of radiation to cancer cells, relative to a single radiation delivery. For all cancer cell lines, a grid field gives a greater toxic effect than a uniform field. The split dose treatment offers an increase in cancer toxicity while preserving normal cells, improving the outcomes of a treatment.

Split-dose low-volume polyethylene glycol is non-inferior but less preferred compared with same-day bowel preparation for afternoon colonoscopy.

Currently, the same-day polyethylene glycol-electrolyte lavage solution (PEG-ELS) regimen is particularly recommended for afternoon colonoscopy as an alternative to the split-dose regimen in western countries. However, in Japan, the split-dose regimen has never been used as a standard colonoscopy preparation regimen. The aim of this study was to compare the efficacy and tolerability of split-dose PEG containing ascorbic acid (ASC) with same-day single dose PEG-ASC in Japan.This was a single-blinded, non-inferiority, two-center, randomized, controlled study. In-hospital patients were randomized to the same-day regimen or the split regimen using a web-based registry system. The same-day group was instructed to take 5 mL of sodium picosulfate in the evening, and on the day of the colonoscopy, they took 1.5 L of PEG-ASC. The split group was instructed to take 1 L of PEG-ASC before the day of colonoscopy, followed by another 1 L of PEG-ASC on the day of colonoscopy. Bowel cleansing was evaluated by the Boston Bowel Preparation Scale.A total of 153 patients were randomized to either the same-day group (n=78, males 60.0%, mean age 62.7 years) or the split group (n=75, 61.3%, 61.9 years). The rates of successful bowel cleansing were 83.3% in the same-day group vs. 92.0% (83.4%-97.0%) in the split group, P=0.10). No serious adverse events occurred in the study population. However, more patients in the same-day group were willing to repeat the same preparation regimen (P<0.001). The split-dose regimen was not inferior to the same-day regimen with respect to the efficacy of bowel preparation, but the patients preferred the same-day regimen.