Spleen phenotype in autosomal dominant polycystic kidney disease

AIM

To evaluate splenic phenotype in autosomal dominant polycystic kidney disease (ADPKD) including presence of cysts and splenomegaly to determine if these are ADPKD related or represent unrelated incidental findings.

MATERIALS AND METHODS

The axial/coronal T2-weighted images of ADPKD patients (n=215) and age/gender-matched controls (n=215) were evaluated for the presence of T2-bright splenic lesions by three blinded observers. Spleen volume (SV) was evaluated in the context of clinical and imaging features as well as results of gene testing for PKD1 and PKD2 mutations.

RESULTS

T2-bright splenic lesions were found in 16 of 215 (7%) ADPKD patients compared to 11 of 215 (5%) control patients (p=0.32) and their prevalence was similar in patients with either PKD1 or PKD2 mutations. Median SV was significantly higher in ADPKD patients than controls (236 [182; 313 ml] versus 176 [129; 264 ml], p<0.0001). In multivariable analysis, height-adjusted SV (htSV) was not associated with the presence of liver cysts, haemorrhagic cysts, or infections; however, htSV was directly associated with height-adjusted total kidney volume (htTKV), a biomarker for ADPKD disease severity.

CONCLUSIONS

The prevalence of T2-bright splenic lesions is similar in ADPKD patients and non-ADPKD controls, suggesting no relation to the diagnosis of ADPKD; however, splenic enlargement in ADPKD compared to controls could not be explained by liver cystic involvement, by infection/inflammatory conditions, or by haemorrhagic renal cysts. This combined with direct correlation of htSV with htTKV, a biomarker of ADPKD severity, suggests splenomegaly may be related to the pathogenesis of ADPKD.

Implications of ICD-10 for Sarcopenia Clinical Practice and Clinical Trials: Report by the International Conference on Frailty and Sarcopenia Research Task Force

Establishment of an ICD-10-CM code for sarcopenia in 2016 was an important step towards reaching international consensus on the need for a nosological framework of age-related skeletal muscle decline. The International Conference on Frailty and Sarcopenia Research Task Force met in April 2017 to discuss the meaning, significance, and barriers to the implementation of the new code as well as strategies to accelerate development of new therapies. Analyses by the Sarcopenia Definitions and Outcomes Consortium are underway to develop quantitative definitions of sarcopenia. A consensus conference is planned to evaluate this analysis. The Task Force also discussed lessons learned from sarcopenia trials that could be applied to future trials, as well as lessons from the osteoporosis field, a clinical condition with many constructs similar to sarcopenia and for which ad hoc treatments have been developed and approved by regulatory agencies.

Implications of ICD-10 for Sarcopenia Clinical Practice and Clinical Trials: Report by the International Conference on Frailty and Sarcopenia Research Task Force

Establishment of an ICD-10-CM code for sarcopenia in 2016 was an important step towards reaching international consensus on the need for a nosological framework of age-related skeletal muscle decline. The International Conference on Frailty and Sarcopenia Research Task Force met in April 2017 to discuss the meaning, significance, and barriers to the implementation of the new code as well as strategies to accelerate development of new therapies. Analyses by the Sarcopenia Definitions and Outcomes Consortium are underway to develop quantitative definitions of sarcopenia. A consensus conference is planned to evaluate this analysis. The Task Force also discussed lessons learned from sarcopenia trials that could be applied to future trials, as well as lessons from the osteoporosis field, a clinical condition with many constructs similar to sarcopenia and for which ad hoc treatments have been developed and approved by regulatory agencies.

Autosomal dominant polycystic kidney disease caused by somatic and germline mosaicism

Autosomal dominant polycystic kidney disease (ADPKD) is a heterogeneous genetic disorder caused by loss of function mutations of PKD1 or PKD2 genes. Although PKD1 is highly polymorphic and the new mutation rate is relatively high, the role of mosaicism is incompletely defined. Herein, we describe the molecular analysis of ADPKD in a 19-year-old female proband and her father. The proband had a PKD1 truncation mutation c.10745dupC (p.Val3584ArgfsX43), which was absent in paternal peripheral blood lymphocytes (PBL). However, very low quantities of this mutation were detected in the father's sperm DNA, but not in DNA from his buccal cells or urine sediment. Next generation sequencing (NGS) analysis determined the level of this mutation in the father's PBL, buccal cells and sperm to be ∼3%, 4.5% and 10%, respectively, consistent with somatic and germline mosaicism. The PKD1 mutation in ∼10% of her father's sperm indicates that it probably occurred early in embryogenesis. In ADPKD cases where a de novo mutation is suspected because of negative PKD gene testing of PBL, additional evaluation with more sensitive methods (e.g. NGS) of the proband PBL and paternal sperm can enhance detection of mosaicism and facilitate genetic counseling.

Simulation of the Impact of Atropisomer Interconversion on Plasma Exposure of Atropisomers of an Endothelin Receptor Antagonist

BMS-207940, a potent endothelin receptor antagonist, exists as rapidly interconverting atropisomers. The plasma interconversion t(1/2) is approximately 2.5 hours at 400 microg/mL under room temperature and decreases to < 0.1 hours at 20 microg/mL, making it extremely difficult to conduct pharmacokinetic studies of individual atropisomers. The pharmacokinetics of the 50/50 racemate of BMS-207940 in humans were reasonably described by a one-compartmental model with an apparent terminal elimination t(1/2) of 15 hours. Given the above rates, simulations were conducted based on a one-compartmental model to explore the possible range of individual rates of atropisomer elimination and potential difference in plasma exposure to the two atropisomers. Simulations demonstrated that the elimination rates of the individual atropisomers are bounded between 0 and 0.046 h(-1) and between 0.046 and 0.092 h(-1), respectively. The estimation of the upper bounds for atropisomer elimination rate constants is robust and relatively insensitive to the rate of atropisomer interconversion compared to the rate of racemate elimination. Simulations of the administration of a single atropisomer or the 50/50 racemate, based on all the possible scenarios of individual atropisomer elimination, showed little difference in plasma exposure to the two atropisomers. Potential differences in plasma exposure to the two atropisomers depend, to a larger extent, on the ratio of the rate of atropisomer interconversion versus racemate elimination and, to a lesser extent, on the conformation of atropisomers administered. When atropisomer interconversion is 10-fold or more rapid than racemate elimination, the largest possible difference in plasma exposure between the two atropisomers is below 20%, regardless of the route and conformation of the atropisomer(s) administered.

Effects of an 11β-hydroxysteroid dehydrogenase type 1 inhibitor, MK-0916, in patients with type 2 diabetes mellitus and metabolic syndrome

AIM

We examined the effects of the 11β-hydroxysteroid dehydrogenase type 1 (HSD1) inhibitor, MK-0916, on the multiple components of the metabolic syndrome (MetS) in patients with type 2 diabetes (T2DM) and MetS.

METHODS

This was a 12-week, multicentre, randomized, double-blind, placebo-controlled study. Patients with T2DM (mean baseline A1C: 7.3%) and National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III)-defined MetS were randomized 1 : 1 : 1 : 1 to 0.5, 2 or 6 mg/day MK-0916 or placebo. The primary efficacy endpoint was a change from baseline at week 12 in fasting plasma glucose (FPG). Secondary endpoints included glycosylated haemoglobin A(1c) (A1C), 2-h postprandial glucose (2-h PPG), body weight, waist circumference, blood pressure and lipid profile.

RESULTS

Treatment with MK-0916 had no significant effect relative to placebo on FPG at week 12. Compared to placebo, 6 mg MK-0916 produced a modest, significant (p = 0.049) reduction in A1C of 0.3% at week 12, but no significant difference was observed in 2-h PPG. Six milligram MK-0916 increased LDL-C relative to placebo by 10.4% (p = 0.041). Treatment with MK-0916 led to modest dose-dependent decreases in blood pressure and body weight. Overall, MK-0916 was generally well tolerated. MK-0916 produced mechanism-based activation of the hypothalamic-pituitary-adrenal axis, resulting in mean increases in adrenal androgen levels that remained within the normal range at all doses tested.

CONCLUSIONS

Inhibition of HSD1 with MK-0916 was generally well tolerated in patients with T2DM and MetS. Although no significant improvement in FPG was observed with MK-0916 compared to placebo, modest improvements in A1C, body weight and blood pressure were observed.

Urine calcium excretion predicts bone loss in idiopathic hypercalciuria

Although idiopathic hypercalciuria (IH) is associated with reduced bone mineral density (BMD), no studies to date have identified predictors of BMD change over an extended period of observation. We have studied change in femoral neck and spine BMD z-scores in men and women with IH and stone disease (IHSF) and their first-degree relatives in order to determine the predictive value of commonly made clinical measurements. Urine calcium excretion was inversely correlated with change in femoral neck z-score over 3 years, and marginally correlated with fall in spine z-score. Markers of bone turnover, serum calcitriol, and urine measurements of acid-base balance such as ammonium and sulfate had no predictive value, nor did calcium intake assessed using a well-established questionnaire. It would appear that IHSF with the highest 24-h urine calcium excretion rates are at highest risk for loss of femoral neck bone mineral over a 3-year period.

Cost analysis of fentanyl and remifentanil in coronary artery bypass graft surgery without cardiopulmonary bypass

BACKGROUND

Opiates such as remifentanil have the potential to reduce time to extubation (TTE), shorten length of stay (LOS) and lower hospital costs, because of a short duration of action. However, the cost of remifentanil is approximately ten times higher than longer-acting opiates like fentanyl.

OBJECTIVES

The objective of this analysis was to compare TTE, LOS and total hospital costs between patients who received remifentanil and fentanyl during off-pump bypass surgery.

METHODS

The study was prospective and observational in design. Consecutive patients who underwent off-pump cardiac bypass surgery and received either remifentanil or fentanyl from September 1998 to August 1999 were screened for study entry. Patient bills and charges were converted to costs using hospital cost-to-charge ratios. The percent of patients' extubated in the operating room (OR), LOS and hospital costs were compared between the groups.

RESULTS

The baseline demographics (age: 66 +/- 12 years mean +/- SD; female 36%) and intraoperative variables were similar between the remifentanil (n=39) and fentanyl (n=20) groups. Patients given remifentanil during surgery were significantly more likely to be extubated in the OR than patients given fentanyl (15 vs. 64%; P < 0.001). Mean LOS was similar in both groups (7.3 +/- 3.1 vs. 8.3 +/- 2.7 days; P=0.27). Patients who received remifentanil incurred lower pulmonary function testing ($0 +/- 0 vs. $34 +/- 103; P=0.045), recovery room ($31 +/- 40 vs. $65 +/- 33; P=0.002) and lower ward costs ($3973 +/- 1719 vs. $4808 +/- 1794; P=0.09) than patients who received fentanyl. Anesthesia costs were higher among patients who received remifentanil ($476 +/- 102 vs. $416 +/- 130; P=0.06). Medical and surgical supplies, OR, intensive care unit, laboratory, respiratory therapy, pharmacy, radiology and transfusion costs were similar between the two groups. The total cost was $15 272 +/- 5556 and $15 616 +/- 4169 in the remifentanil and fentanyl groups, respectively (P=0.81).

CONCLUSION

Remifentanil, when used in off-pump bypass surgery, is associated with an increased likelihood of extubation in the OR. However, LOS and total hospital costs remain unchanged.

Characterization of immunologic tolerance induced by transfusion of UV-B--irradiated allogeneic mononuclear leukocytes

Transfusions of UV-B--irradiated peripheral blood mononuclear cells (UV-B--PBMCs) from BALB/c (H-2(d)) mice into CBA (H-2(k)) mice can induce humoral immune tolerance to H-2(d) antigens, and the induced tolerance is partially mediated by negative regulatory PBMCs. To further identify which subset of spleen mononuclear leukocytes (MNLs) in the tolerant CBA mice is responsible for the negative regulatory activity, adoptive transfer experiments were conducted using spleen MNLs from the tolerant CBA mice. Results showed that only CD4(+) T cells could transfer the negative regulatory activity in a dose-dependent manner. This negative regulatory activity was significantly reduced when CD25(+) helper T cells were removed. Further study suggested that inhibition of IL-12 production by UV-B--irradiated PBMCs played a role in the induction of immune tolerance. In vitro study of the cytokine production profile by CBA CD4(+) T cells, after stimulation with gamma-irradiated BALB/c spleen cells, revealed an enhanced production of the type 2 T-cell cytokines after tolerance induction. Induction of tolerance also prevented the development of cytotoxic T cells in CBA mice against BALB/c MNLs. Adoptive transfer study suggested that the cellular immune tolerance was also mediated by CD4(+) negative regulatory T cells. The induced immune tolerance was nullified after 400 cGy sublethal gamma irradiation. These results suggest that the ex vivo study of cytokine production by T cells may be used to monitor tolerance induction and the selection of gamma radiation dose is critical for potential clinical application of the tolerance induced by UV-B--PBMCs. (Blood. 2001;98:1239-1245)

Ticlopidine inhibits phenytoin clearance

Because cases of phenytoin toxicity during concomitant ticlopidine therapy have been reported, we investigated the effects of multiple doses of ticlopidine on phenytoin pharmacokinetics in six patients receiving phenytoin monotherapy. Two steady-state dosing rate and serum phenytoin minimum concentration (Cmin) pairs were obtained for each patient administered oral phenytoin alone, then phenytoin plus 250 mg ticlopidine twice daily. All patients had serum Cmin ticlopidine values of 0.06 to 0.25 microg/mL when receiving ticlopidine. Individual pharmacokinetic parameters for phenytoin were calculated. The Michaelis-Menten constant (Km) was determined as the slope and maximum velocity (Vmax; equivalent to the maximal rate of elimination or the maximum daily dose that can be metabolized) as the y-intercept of the linear Michaelis-Menten plot. Mean phenytoin Km significantly increased from 5.8 to 12.3 during ticlopidine coadministration compared with administration of phenytoin alone (P = .02). Mean phenytoin Vmax was not significantly changed by the coadministration of ticlopidine. These data indicate that ticlopidine inhibits the clearance and alters the clinical pharmacokinetics of phenytoin so that dosage adjustment of phenytoin should be considered when ticlopidine is coadministered. The results are consistent with previous human liver microsome findings that ticlopidine is a potent inhibitor of CYP2C19, a P450 isozyme that is significantly responsible for phenytoin metabolism.

Idiopathic intracranial hypertension in prepubertal pediatric patients: characteristics, treatment, and outcome

PURPOSE

To report the features of idiopathic intracranial hypertension in prepubertal children, with emphasis on presentation, treatment, and outcome.

METHODS

We retrospectively reviewed the charts of all patients 11 years and younger diagnosed with idiopathic intracranial hypertension at two university-affiliated medical centers. Inclusion critera included papilledema, normal brain computed tomography or magnetic resonance imaging, cerebrospinal fluid pressure greater than 200 mm H2O, normal cerebrospinal fluid content, and a nonfocal neurologic examination except for sixth nerve palsy. Patients with concomitant systemic illness were excluded.

RESULTS

Of the 10 patients, four were girls and six were boys. Only one patient was obese. The most common presenting symptoms were stiff neck (four patients) and diplopia (four patients), and the most common presenting sign was strabismus (eight patients). Six of eight patients with strabismus had abducens nerve palsy (four bilateral), one patient had a sensory exotropia, and one had a comitant esotropia. Visual field abnormalities were present in 11 of 13 eyes (85%), and severe visual loss resulting in no light perception vision occurred in one eye of one patient. Nine patients were treated medically, four with a combination of prednisone or dexamethasone and acetazolamide and five with acetazolamide alone. One patient in this group also required a lumboperitoneal shunt. One patient was treated with lumbar puncture only. Resolution of papilledema occurred rapidly in all patients, with a mean of 4.7 +/- 2.6 months. Resolution of sixth nerve palsy also occurred rapidly in four of six patients in a mean of 1.6 +/- 1.2 months. One patient required strabismus surgery for persistent esotropia and one was lost to follow-up.

CONCLUSIONS

Idiopathic intracranial hypertension in prepubertal children is rare and is different than the disease in adults. In our series, there appeared to be no sex predilection, and obesity was uncommon. Children are likely to present with strabismus and stiff neck rather than headache or pulsatile tinnitus. Both papilledema and sixth nerve palsy resolved rapidly with treatment. However, children can sustain loss of visual field and visual acuity despite treatment.

Impaired adrenocortical response to stress by brown trout, Salmo trutta, living in metal-contaminated waters of the Eagle River, Colorado

Brown trout, Salmo trutta, were collected from two sites contaminated with cadmium (Cd) and zinc (Zn) and one uncontaminated site. These fish were subjected to a continuous confinement stressor in wire cages placed in the river (moderate stress) or in 5-gal. plastic buckets on land (severe stress). Plasma cortisol and corticotropin (ACTH) were determined for fish in buckets by radioimmunoassay after 0, 1, 3, 12, or 24 h of confinement. Plasma cortisol and ACTH levels of brown trout from both contaminated and uncontaminated sites initially were the same and increased with time. However, the rise in plasma cortisol was delayed significantly in fish residing in contaminated sites, even though ACTH secretion initially was elevated compared with control trout. Furthermore, secretion of cortisol and ACTH by these fish declined significantly between 3 and 24 h of confinement. Fish from the uncontaminated site responded more rapidly to confinement with increased cortisol secretion and elevated levels of ACTH and continued to exhibit elevated levels of both hormones up to 24 h of confinement. Caged fish examined after 0, 3, 12, and 24 h of confinement exhibited similar plasma cortisol responses regardless of previous exposure to metals. These results suggest that the overall response to severe, short-term confinement stress by the hypothalamo-pituitary-adrenocortical axis of fish chronically exposed to Cd and Zn was depressed and that these fish could not sustain the stress response as readily as fish living in uncontaminated water.

Designing a system for managing the performance of mental health managed care: an example from New York State's prepaid mental health plan

The organization, financing, and delivery of publicly funded behavioral health services are undergoing massive changes nationwide. Managed care principles and practices are being implemented widely and are being relied on increasingly to meet the challenges of containing costs and improving service effectiveness. To meet these goals, comprehensive systems are under development for measuring and reporting outcomes experienced by individuals who received services and for assessing the impact of managed care strategies on the service delivery system. This article presents an example from the Prepaid Mental Health Program in New York State. It highlights the development, implementation, and early experiences with the plan's performance management system for public sector managed behavioral health, a basis for continuous quality improvement activities and information reporting products such as report cards. Policy, administrative, and financial implications are illuminated.

Unusual ocular motility disturbances with increased intracranial pressure

We evaluated nine patients with external ophthalmoparesis and increased intracranial pressure. The eye movements normalized when the intracranial pressure was controlled. Investigations for an underlying cause of elevated cerebrospinal fluid pressure are warranted when ocular motility disorders are present.

Association of increased basement membrane invasiveness with absence of estrogen receptor and expression of vimentin in human breast cancer cell lines

Lack of estrogen receptor (ER) and presence of vimentin (VIM) associate with poor prognosis in human breast cancer. We have explored the relationships between ER, VIM, and invasiveness in human breast cancer cell lines. In the matrigel outgrowth assay, ER+/VIM- (MCF-7, T47D, ZR-75-1), and ER-/VIM- (MDA-MB-468, SK-Br-3) cell lines were uninvasive, while ER-/VIM+ (BT549, MDA-MB-231, MDA-MB-435, MDA-MB-436, Hs578T) lines formed invasive, penetrating colonies. Similarly, ER-/VIM+ cell lines were significantly more invasive than either the ER+/VIM- or ER-/VIM- cell lines in the Boyden chamber chemoinvasion assay. Invasive activity in nude mice was only seen with ER-/VIM+ cell lines MDA-MB-231, MDA-MB-435 and MDA-MB-436. Hs578T cells (ER-/VIM+) showed hematogenous dissemination to the lungs in one of five mice, but lacked local invasion. The ER-/VIM+ MCF-7ADR subline was significantly more active than the MCF-7 cells in vitro, but resembled the wild-type MCF-7 parent in in vivo activity. Data from these cell lines suggest that human breast cancer progression results first in the loss of ER, and subsequently in VIM acquisition, the latter being associated with increased metastatic potential through enhanced invasiveness. The MCF-7ADR data provide evidence that this transition can occur in human breast cancer cells. Vimentin expression may provide useful insights into mechanisms of invasion and/or breast cancer cell progression.

An unusual type of infantile lipofuscinosis

The case of a child is described who at the age of 2 years showed the first evidence of a developing neurological disease. Within a couple of years, profound mental retardation and severe motor deficit with spastic tetraplegia became established. No seizures and no pigmentation of the retina were observed. The condition remained practically unchanged for some 8 years and the patient died at 12 years of age of terminal bronchopneumonia. At autopsy there was conspicuous diffuse atrophy of the brain. The cerebral cortex was particularly involved. Most of the cortical neurons were destroyed and neuroglia showed abundant proliferation. The few remaining neurons contained inclusion material which was identified as lipofuscin. Noticeable cedifferences from the various types of amaurotic idiocies are noted and similarities to a case of lipidosis recently reported from Finland are suggested.

Arteriosclerosis due to homocyst (e) inemia. Failure to reproduce the model in weanling rabbits

Weanling rabbits were injected subcutaneously daily for 35 days with homocysteine thiolactone in an attempt to repeat the results of McCully and Ragsdale. We failed to produce sustained homocyst(e)inemia (or homocysteine thiolactonemia); indeed, transient homocyst(e)inemia could only be demonstrated with a much higher dose of the free base of homocysteine given intraperitoneally. Homocysteine thiolactonemia was observed up to 15 minutes, only after an intravenous injection of homocysteine thiolactone. Analysis of urine and various organs for free amino acids also failed to detect homocyst(e)ine or the thiolactone. Morphologically, we were unable to distinguish between the experimental and control animals.