The Fate of Residual Fragments After Percutaneous Nephrolithotomy: Results from the Endourologic Disease Group for Excellence Research Consortium

Background: Residual fragments (RFs) after percutaneous nephrolithotomy (PCNL) have a significant impact on patients' quality of life and clinical course. There is a paucity of studies that evaluate the natural history of RFs after PCNL. The objective of this study is to compare rates of reintervention, complications, stone growth, and passage in patients with RFs >4, ≤4, and ≤2 mm after PCNL. Methods: Sites from the Endourologic Disease Group for Excellence (EDGE) research consortium examined data of PCNL patients from 2015 to 2019 with at least 1-year follow-up. RF passage, regrowth, reintervention, and complications were recorded and RFs were stratified into >4 and ≤4 mm groups, as well as >2 and ≤2 mm groups. Potential predictors for stone-related events after PCNL were determined using multivariable logistic regression analysis. It was hypothesized that larger RF thresholds would result in lower passage rates, faster regrowth, and greater clinically significant events (complications and reinterventions) than smaller RF thresholds. Results: A total of 439 patients with RFs >1 mm on CT postoperative day 1 were included in this study. For RFs >4 mm, rates of reintervention were found to be significantly higher and Kaplan-Meier curve analysis showed significantly higher rates of stone-related events. Passage and RF regrowth were not found to be significantly different compared with RFs ≤4 mm. However, RFs ≤2 mm had significantly higher rates of passage, and significantly lower rates of fragment regrowth (>1 mm), complications, and reintervention compared with RFs >2 mm. On multivariable analysis, older age, body mass index, and RF size were found to be predictive of stone-related events. Conclusions: With the largest cohort to date, this study by the EDGE research consortium further confirms that clinically insignificant residual fragment is problematic for patients after PCNL, particularly in older more obese patients with larger RFs. Our study underscores the importance of complete stone clearance post-PCNL and challenges the use of Clinically insignificant residual fragment (CIFR).

The effect of daily probiotics on the incidence and severity of necrotizing enterocolitis in infants with very low birth weight

Background:

Necrotizing enterocolitis remains a leading cause of morbidity and mortality in premature infants. The role of prophylactic probiotics in its prevention is unclear. This study evaluates the effect of routine probiotics on the incidence and severity of necrotizing enterocolitis in infants with very low birth weight in the neonatal intensive care unit.

Methods:

This retrospective cohort study compared infants cared for at a single institution before and after implementation of routine probiotic administration (2014– 2018). Babies born after July 2016 received probiotics containing Bifidobacterium and Lactobacillus daily until 35 weeks corrected gestational age. Baseline characteristics, necrotizing enterocolitis incidence and severity, infections, mortality, and length of stay were compared between groups.

Results:

Of the 665 infants included in the study, 310 received probiotics and 355 did not. The 2 groups did not differ with regard to gestational age, birth anthropometrics, mode of delivery, comorbidities, and type of enteral feed. The incidence of necrotizing enterocolitis (Bell’s stage 2 of 3) was similar between groups (4% v. 5%, p = 0.35), as was its severity (p = 0.10). In addition, there were no significant differences in mortality and length of stay between the groups. Significantly fewer infants receiving probiotics developed infections (27% v. 34%, p = 0.046), with the rate of urinary tract infections having the largest reduction.

Conclusion:

The routine use of Bifidobacterium and Lactobacillus probiotics in infants with very low birth weight did not significantly affect the incidence and severity of necrotizing enterocolitis. However, the use of probiotics was associated with fewer overall infections.

Measurements using mammography and ultrasonography underestimate the size of high-volume ductal carcinoma in situ

BACKGROUND

Surgical decisions for ductal carcinoma in situ (DCIS) are based on lesion sizes. This study aims to determine the accuracy of pre-operative imaging in estimating the size of DCIS.

METHODS

This was a retrospective review of clinicopathologic data of patients treated for DCIS with breast conserving surgery (BCS) between 2012 and 2018. Mammographic and sonographic lesion sizes were compared with final pathology sizes.

RESULTS

For the 152 lesions visible on mammography, mean size on imaging was significantly smaller when compared to final pathology (2.3 vs. 3.6 cm, p < 0.001). The mean difference of 1.3 cm was a significant underestimation with a correlation coefficient of 0.367 (p < 0.001). For 48 sonographically visible lesions, the radiologic size was significantly smaller than pathologic size (1.7 vs. 4.1 cm, p < 0.001), but the degree of underestimation was not significantly correlated (p = 0.379).

CONCLUSION

DCIS size was significantly underestimated by imaging. This must be taken into consideration during surgical planning.

Factors in Sustained Compliance to a Symptom-Reporting Mobile Application: Implications for Clinical Implementation

Background: The Internet-based Computerized Patient Assessment System (iComPAsS), a remote pain- and symptom-reporting application was developed to optimize pain monitoring and management. This subanalysis sought to examine factors influencing compliance, to gauge the sustainability of its effects and to guide further development and implementation as part of usual care. Aim: This analysis sought to examine factors influencing compliance, to gauge the sustainability of its effects and to guide further development and implementation as part of usual care. Methods: Patients ≥ 18 years old, with cancer and moderate-severe pain were randomized to standard pain management with pain diary or iComPAsS. Pain and symptom severity (using Edmonton Symptom Assessment Scale) and compliance (to iComPAsS or diary) were evaluated at week 0, 3, 6, 12 and 20. The Treatment Self-regulation Questionnaire (TSRQ), used to assess patient motivation, was administered at week 0, 6, 12 and 20. Pain levels and compliance were compared between the groups using the Student t-test. The Pearson correlation coefficient was used to examine the relationship between compliance and pain control, perceived competence in pain self-care, and relative autonomy index. Results: Out of 100 patients enrolled, 76 were included in the analysis (control; 37; iComPAsS, 39). Baseline pain levels and TSRQ characteristics were similar between the groups. Initial compliance and pain control at week 3 were significantly higher in the iComPAsS group. For the iCompAsS group, compliance directly correlated with uncontrolled pain and intrinsic motivation, and was more sustained compared with the control group. Conclusion: The iComPAsS elicited rapid uptake and sustained compliance through intrinsic motivation. When adopting the iComPAsS for clinical use, patient baseline motivation levels may be assessed using the TSRQ, and depressive symptoms and other barriers to engagement must be identified.

Effect of FK506 in reducing scar formation by inducing fibroblast apoptosis after sciatic nerve injury in rats

We previously demonstrated that FK506, a generally applied immunosuppressant in organ transplantation, could promote peripheral nerve regeneration through reducing scar formation. However, little is known about how FK506 reduces scar formation. Herein we investigated the influence of FK506 on fibroblast proliferation and its correlation with scar formation after sciatic nerve injury in rats, and further explored the effect of FK506 on fibroblast proliferation and apoptosis in vitro. Masson staining and immunohistochemistry revealed that scar area and fibroblast number in the nerve anastomosis of sciatic nerve-injured rats were significantly reduced after FK506 administration. The scar area had a significant positive correlation with the fibroblast number, as detected by linear correlation analysis. CCK-8 assay and flow cytometry indicated that FK506 also inhibited proliferation and induced apoptosis of fibroblasts in vitro. It was primarily phosphorylation of JNK and ERK that were activated during the apoptosis of fibroblast. Pretreatment of cells with JNK inhibitor, SP600125, or ERK inhibitor, PD98059, could inhibit FK506-induced fibroblast apoptosis, respectively. Moreover, simultaneous application of both inhibitors had additive roles in cell protection from apoptosis. These results suggest that FK506-induced fibroblast apoptosis contributes to the suppression of fibroblast proliferation and then results in the reduction of scar formation in sciatic nerve-injured rat, and that JNK and ERK are involved in FK506-induced fibroblast apoptosis.

Epithelial stem/progenitor cells in lung postnatal growth, maintenance, and repair

The adult lung consists of a trachea leading into a system of branched airways ending in millions of alveolar sacs. It contains many different epithelial cell types arranged in precise patterns along the proximodistal axis. Each region of the lung has the capacity to repair through the proliferation of different epithelial cell types. However, the precise identity of the cells mediating repair is not fully resolved. To address this problem, we are using genetic lineage-labeling techniques in the mouse. The tools we have made will also be useful for understanding how progenitor cell behavior is regulated under normal and pathological conditions.

Unusual persistence in healthy volunteers and ill patients of hyperimmune immunoglobulin directed against multiple Pseudomonas O-chain and Klebsiella serotypes after intravenous infusion

Persistence of intravenous (i.v.) hyperimmune immunoglobulin (100 mg/kg) directed against clinically predominant serotypes of Pseudomonas and Klebsiella in ill, febrile patients was compared to healthy volunteers to determine if ill patients have a decreased Ig half-life resulting in an increased immunoglobulin requirement. Type-specific antibodies were measured by ELISA for 83 days in eight healthy volunteers and for 35 days in eight ill patients with surgical complications or hematologic malignancy. Mean values and fold rises of antibody concentrations for the two groups were above preinfusion values at 35 days. The antibody fold rises in patients and in healthy volunteers were similar. Type-specific antibody levels in some patients increased after illness coincident with elevation of total immunoglobulins. We conclude that the duration of potentially therapeutic levels of infused type-specific hyperimmune immunoglobulin may persist for a longer period of time than what has been measured for total immunoglobulin. While the mechanism of this persistence remains to be characterized, the possibility of type-specific antibody synthesis induced by immunoglobulin administration must be considered.

Does bowel preparation improve the quality of abdominal gallium scintigraphy?

Physiological accumulation of gallium in the intestine is a major weakness of gallium scintigraphy in evaluating the abdomen. In this study, we used two different cathartics to evaluate the efficacy of bowel cleansing in improving the quality of abdominal gallium imaging. One hundred and fifty patients underwent gallium scintigraphy and were randomly divided into three groups. Group A received no bowel preparation, Group B received 30 ml of castor oil the night before imaging, and Group C received bisacodyl the night before imaging. Gallium activity in the intestine was rated on a three-point scale from 0 to II based on the anterior view of a delayed 48-h gallium image. Our data showed that the incidence of gallium accumulation in the small intestine was low. On the contrary, there was high prevalence of gallium activity in the colon. Forty-eight percent of Group A patients had obvious gallium activity in the colon. The percentage decreased significantly to 28% and 22% in Groups B and C, respectively. No significant difference was noted between Group B and Group C. In conclusion, our data suggest that the application of either castor oil or bisacodyl significantly improves the quality of 48-h abdominal gallium scintigraphy. There were no significant differences in the efficacy of bowel cleansing on gallium activity between these two laxatives.

Modulation of excitatory synaptic transmission by low concentrations of glutamate in cultured rat hippocampal neurons

1. The effects of low micromolar concentrations of glutamate on fast excitatory synaptic responses were studied in microcultures of postnatal rat hippocampal neurons using whole-cell patch clamp recordings. 2. Glutamate depressed the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor component of excitatory autaptic currents (EACs) with an EC50 of 3.8 microM. 3. Both pre- and postsynaptic effects contributed to the depression of AMPA receptor-mediated EACs. Cyclothiazide and wheatgerm agglutinin, agents which inhibit AMPA receptor desensitization, partially reversed the depression produced by glutamate, as did pertussis toxin, an agent that blocks presynaptic inhibition mediated by metabotropic glutamate receptors. 4. In neurons in which both the AMPA and N-methyl-D-aspartate (NMDA) receptor components of EACs were examined, low concentrations of glutamate depressed the NMDA component of EACs to a greater extent. The EC50 for inhibiting the NMDA component was 1.3 microM. 5. Calcium-dependent desensitization of postsynaptic NMDA receptors contributed to the depression of NMDA receptor-mediated synaptic responses. Both depolarization of postsynaptic neurons to +70 mV to decrease Ca2+ influx via NMDA channels and inclusion of high concentrations of a calcium chelator in recording pipettes decreased the depression of NMDA receptor-mediated EACs. 6. Threo-3-hydroxy-aspartate (THA), an inhibitor of glutamate transport, depressed EACs by about 10% and increased the degree of depression produced by 2.5 microM glutamate, suggesting that glutamate transport in microcultures helps to control ambient glutamate levels. 7. Because the normal extracellular concentration of glutamate is about 1 microM, these results suggest that the ambient glutamate level is an important determinant of synaptic efficacy. Relatively small changes in extracellular glutamate can alter fast excitatory synaptic transmission by both presynaptic and postsynaptic mechanisms.

Passive and synaptic properties of hippocampal neurons grown in microcultures and in mass cultures

1. We used whole cell recordings to compare passive membrane properties and synaptic properties of postnatal rat hippocampal neurons grown for 7-15 days in either conventional mass cultures or on physically restricted microisland cultures. Despite matching microisland and mass culture cell across several variables, there were significant differences between neurons in the two groups regarding passive membrane characteristics and synaptic properties. 2. Microisland neurons displayed significantly faster charging of the membrane capacitance than mass culture counterparts matched with microisland neurons for age, somal diameter, and transmitter phenotype. When we used a two-compartment equivalent circuit model to quantify this result, microisland neurons displayed approximately half the distal capacitance of mass culture neurons. These data suggest that microisland neurons elaborate less extensive neuritic arborizations than mass culture neurons. 3. Evoked synaptic responses were enhanced on microislands compared with mass cultures. Excitatory and inhibitory autaptic currents were more frequent and displayed larger amplitudes on single-neuron microislands than in matched mass culture neurons. 4. In recordings from pairs of neurons in the two environments, we observed a significantly higher probability of obtaining a monosynaptic response on two-neuron microislands than in matched mass culture pairs (85% vs. 42%). Evoked excitatory postsynaptic currents were also significantly larger in the microisland environment, with evoked excitatory synaptic currents from two-neuron microislands exhibiting a mean amplitude 20-fold larger than mass culture monosynaptic responses. 5. The differences in evoked synaptic responses were not reflected in differences in the amplitude or frequency of spontaneous miniature excitatory postsynaptic currents (mEPSCs). Analysis of mEPSC rise times, decay times, and peak amplitudes within individual cells suggests that electrotonic filtering is not an important contributor to the variability of peak amplitudes and decay times of synaptic currents in cells of either culture environment. However, composite data across neurons in both cultures reveal a significant correlation between mEPSC rise and decay times. 6. Out results suggest that the microisland preparation may be a useful tool for exploring factors that influence synapse formation and development. Additionally, the preparation is a particularly convenient model for the study of single-neuron-mediated synaptic events.

Safety and immunogenicity of a polyvalent Escherichia coli vaccine in human volunteers

Since a limited number of O serogroups account for nearly 70% of bacteremic and meningitic Escherichia coli isolates, a polyvalent vaccine was made by conjugating a Pseudomonas aeruginosa exotoxin A carrier protein to the O polysaccharide of 12 serogroups of E. coli (O1, O2, O4, O6-O8, O12, O15, O16, O18, O25, O75). No serious reactions occurred in 88 vaccinees. Four-fold or greater increases in ELISA antibody levels over baseline were greatest (> 60% of vaccinees) for O1, O2, O6-O8 and O15; intermediate (approximately 50%) for O18 and O75, and poorest (> or = 45%) for O4, O12, O16, and O25. Responses with functionally active opsonophagocytic antibody generally paralleled ELISA antibody responses. With the availability of a safe, immunogenic E. coli vaccine, active and passive immunization strategies merit further development as adjunctive treatment for E. coli bacteremia and neonatal meningitis.

Barbiturate depression of a K+ dependent inhibitory synapse is independent of dendritic cable filtering

Technical limitations with intracellular electrophysiological methods usually restrict recording of postsynaptic potentials only from neuronal soma, a site remote from the actual synapse. The intervening dendritic cable interposed between the actual synapse and the site of recording can significantly filter the synaptic signal. Therefore, investigations of drug effect on synaptic mechanisms, based on postsynaptic recordings obtained at the soma, must be interpreted with care. The potential role of dendritic cable filtering in the atypical pentobarbital depression of a K(+)-dependent inhibitory synapse between the P to Nut cell in the posterior packet of the leech was investigated. The effective electrical geometry under the conditions of control and 0.5 mM PNB sufficient to completely abolish the postsynaptic potential were determined from analyses of the membrane charging curves assuming the lumped-soma-short-cable model. Under the control condition, the postsynaptic Nut cell exhibits dendritic dominance with rho = 2.52, normalized equivalent cable length L = 1.08, and a membrane time constant tau o = 52 ms. With phenobarbital application, changes in the geometrical parameters consistent with a decrease in the specific membrane resistance Rm are observed. Simulation of the drug induced change in the electrical geometry demonstrates that the decrease in the post synaptic potential is largely due to the decrease in the soma input resistance and an increase in the cable filter contributes little to the observed depression of the postsynaptic potential. However, the combined effect of the decrease in the input resistance and the increase in the cable filtering of synaptic current is insufficient in explaining the observed total block of the synaptic potential by PNB.(ABSTRACT TRUNCATED AT 250 WORDS)