Whole genome amplification of cell-free DNA enables detection of circulating tumor DNA mutations from fingerstick capillary blood

The ability to measure mutations in plasma cell-free DNA (cfDNA) has the potential to revolutionize cancer surveillance and treatment by enabling longitudinal monitoring not possible with solid tumor biopsies. However, obtaining sufficient quantities of cfDNA remains a challenge for assay development and clinical translation; consequently, large volumes of venous blood are typically required. Here, we test proof-of-concept for using smaller volumes via fingerstick collection. Matched venous and fingerstick blood were obtained from seven patients with metastatic breast cancer. Fingerstick blood was separated at point-of-care using a novel paper-based concept to isolate plasma centrifuge-free. Patient cfDNA was then analyzed with or without a new method for whole genome amplification via rolling-circle amplification (WG-RCA). We identified somatic mutations by targeted sequencing and compared the concordance of mutation detection from venous and amplified capillary samples by droplet-digital PCR. Patient mutations were detected with 100% concordance after WG-RCA, although in some samples, allele frequencies showed greater variation likely due to differential amplification or primer inaccessibility. These pilot findings provide physiological evidence that circulating tumor DNA is accessible by fingerstick and sustains presence/absence of mutation detection after whole-genome amplification. Further refinement may enable simpler and less-invasive methods for longitudinal or theranostic surveillance of metastatic cancer.

A 10-Fr ultrasound catheter with integrated micromotor for 4-D intracardiac echocardiography

We developed prototype real-time 3-D intracardiac echocardiography catheters with integrated micromotors, allowing internal oscillation of a low-profile 64-element, 6.2-MHz phased-array transducer in the elevation direction. Components were designed to facilitate rotation of the array, including a low-torque flexible transducer interconnect and miniature fixtures for the transducer and micromotor. The catheter tip prototypes were integrated with two-way deflectable 10-Fr catheters and used in in vivo animal testing at multiple facilities. The 4-D ICE catheters were capable of imaging a 90° azimuth by up to 180° elevation field of view. Volume rates ranged from 1 vol/sec (180° elevation) to approximately 10 vol/sec (60° elevation). We successfully imaged electrophysiology catheters, atrial septal puncture procedures, and detailed cardiac anatomy. The elevation oscillation enabled 3-D visualization of devices and anatomy, providing new clinical information and perspective not possible with current 2-D imaging catheters.

A randomized pilot study in Type 1 diabetes complicated by severe hypoglycaemia, comparing rigorous hypoglycaemia avoidance with insulin analogue therapy, CSII or education alone

AIM

To determine potential for amelioration of recurrent severe hypoglycaemia without worsening in overall control in individuals with long-standing Type 1 diabetes (T1DM).

METHODS

Twenty-one people with T1DM characterized by altered hypoglycaemia awareness and debilitating severe hypoglycaemia were randomized in a pilot 24-week prospective study to optimized analogue therapy (ANALOGUE; lispro/glargine); continuous subcutaneous insulin infusion therapy (CSII; lispro); or re-education with relaxation of blood glucose targets on existing conventional insulin regimen (EDUCATION). Glycaemic profiles and duration of biochemical hypoglycaemia were measured by continuous subcutaneous glucose monitoring and self-monitored blood glucose.

RESULTS

Further severe hypoglycaemia was prevented in five participants (71%) in each group (P = 0.06). Incidence of severe hypoglycaemia was: 0.6 (ANALOGUE), 0.9 (CSII), and 3.7 (EDUCATION) episodes per patient year. Restoration of hypoglycaemia awareness was confirmed by validated questionnaire in three (43%) ANALOGUE, four (57%) CSII and five (71%) EDUCATION patients. Glycated haemoglobin (HbA1c) was significantly improved in the ANALOGUE group between weeks 0 and 24 (8.6 +/- 1.1 vs. 7.6 +/- 0.8%; P = 0.04 for change). Non-significant improvement was seen in the CSII group (8.5 +/- 1.9 vs. 7.4 +/- 1.0%; P = 0.06). No change in HbA1c was seen in the EDUCATION group (8.5 +/- 1.1 vs. 8.3 +/- 1.0%; P = 0.54). There were no episodes of diabetic ketoacidosis or any other adverse events in any group.

CONCLUSIONS

In this pilot randomized trial comparing optimized ANALOGUE, CSII or EDUCATION alone in unselected individuals with recurrent severe hypoglycaemia, we show potential for restoring hypoglycaemia awareness and preventing further severe hypoglycaemia with concomitant improvement in glycaemic control in ANALOGUE and CSII groups.

284THE EFFECT OF FEEDING PROPYLENE GLYCOL TO DAIRY COWS DURING THE EARLY POSTPARTUM PERIOD ON SERUM INSULIN CONCENTRATION AND THE RELATIONSHIP WITH OOCYTE DEVELOPMENTAL COMPETENCE

High yielding dairy cows are typically in negative energy balance postpartum (pp). It has been shown that initiation of the first pp ovulation and, therefore, the resumption of normal oestrous cycles is delayed in high genetic merit dairy cows and is associated with lower circulating insulin concentration (Gutierrez et al., 1999 J. Reprod. Fertil. 24, 32 abst). Evidence shows that propylene glycol (PG) rapidly elevates systemic concentrations of insulin (Bremmer et al., 2000 J. Dairy Sci. 83, 2239–2251). The aim of this study was to determine the effects of PG feeding to dairy cows in the early pp period, on serum insulin and ovarian function, and on oocyte developmental competence after in vitro maturation, fertilization, and culture. Thirteen Holstein-Friesian cows were assigned to PG (n=6) or control (n=7) groups. Each treated cow received 500mL of PG and each control was given 500mL of water daily from Day 5pp until day of AI. Blood samples for insulin were collected at 0, 30, 60 and 90min post-drenching on Days 5, 15 and 25 pp. All cows were fed 3kg concentrates at milking (twice daily) and had ad libitum access to a 50:50 maize silage : grass silage forage from the time of last blood collection. Oocytes were collected by ovum pick-up (OPU) in four sessions (following treatment with pFSH) beginning on Day 25–35 pp. The recovered oocytes were graded (Grade 1 to 4) in terms of their surrounding cumulus cells and the appearance of the cytoplasm. Grade 1–2 oocytes were matured in vitro, then fertilized using frozen-thawed bull semen, and subsequently cultured up to Day 8 in synthetic oviduct fluid. All data were analyzed using SAS version 6.12 and split-plot designs, following square root or arc sine transformation, if appropriate. PG significantly increased (P<0.001) serum insulin concentration (0min: 1.55±0.19; 30min: 4.48±0.82; 60min: 4.74±0.72; 90min: 4.10±0.56) compared to the control group (0min: 1.91±0.28; 30min 1.96±0.27; 60min: 2.37±0.44; 90min: 2.04±0.26). The follicle size distribution was similar between treated and control cows for categories 2–4mm (4.0±0.47; 4.3±0.70), 8–10mm (3.2±0.47; 2.5±0.39), and >10mm (0.42±0.12; 0.67±0.17). However, there were significantly more follicles in the 5–7mm category (6.2±0.82 v. 3.3±0.43; P<0.05) for treated cows. The number of follicles punctured (13.8±1.02; 10.7±1.04), the number of oocytes recovered (4.5±0.53; 3.5±0.61), and the number of Grade 1–2 oocytes (2.8±0.35; 1.8±0.35) were not different between treated and control cows. Although cleavage rate (68.3 v. 58.9%) and blastocyst yield (25.3 v. 14.4%) were higher for treated cows, the differences were not significant. In conclusion, these results indicate that feeding cows with PG during the early pp period increased the circulating insulin concentration. However, the developmental competence of the recovered oocytes did not differ between the groups.

Surgical "touch artefacts" of the cerebral cortex. An experimental study with light and electron microscopic analysis

In surgically excised brain tissue a very common artefact, unrelated to the presence or absence of a genuine pathological process, involves the water content of cortical neurons. Nerve cells may show massive watery swelling of both their cytoplasm and nuclei or conversely may become shrunken and dark-staining. The most important aspect of this alteration is that it may lead to mistaken histopathological interpretation, but the question also arises whether such changes, presumably caused by exposure, touch, pressure or the combination of all 3, in the living patient, would persist after surgery and would eventually result in irreversible damage to the involved neurons? Thirty rats were operated in this experiment: craniotomy and opening of the dura mater was done over one convexity and slight pressure (uniformly calibrated for all animals) was applied to the exposed cortex. The wound was closed and the animals were sacrificed at various intervals, ranging from immediately after the operation to 6 weeks. The areas that suffered compression were examined by light and electron microscopy. Initial changes included marked watery swelling of neuronal perikarya and nuclei which predominated over pyknotic changes. The changes thus produced were identical with those seen in portions of the cortex excised immediately after pressure was applied to the area in 10 additional rats.(ABSTRACT TRUNCATED AT 250 WORDS)

A profile of the noncompliant patient: a thirty-month review of outpatient psychiatry referrals

Missed appointments to outpatient psychiatry programs have been identified as a major form of noncompliance in the literature. Over a two-and-a-half year period, 874 referrals to the outpatient psychiatry department of a large teaching hospital were examined for significant differences between compliant and noncompliant patients. Noncompliant patients comprised 17.8% of the total number of cases dispositions and were significantly more likely to be single, diagnosed personality disorder or substance abuse, and referred from the Emergency Department than complaint patients. Further analysis of emergency referrals, the single most significant predictor, indicated that patients from this referral source were more likely to be male, unmarried, unemployed or on welfare, and diagnosed personality disorder or substance abuse than referrals from general practice and internal sources. The results are discussed in light of previous research, and recommendations are made for increasing compliance to outpatient appointments.

Predictive testing with the subrenal capsule assay

Measurement of drug activity as an oncolytic effect, use of the control only to monitor the quality of tissue implanted, and the rapid clearance of necrotic tissue from the subcapsular site, as significant factors incorporated into the design of the assay, have permitted use of a simple tumor size parameter for evaluating drug activity. The simplicity and economy of such a parameter, the predictability and reproducibility of the 6-day assay observed thus far, and evidence that the assay does measure a biological property of the tumor apart from host response, have warranted the continued use of the 6-day time frame and the normal immunocompetent CDF1 mouse as xenograft host. These studies have demonstrated the feasibility of using human tumor explants obtained from a variety of solid human malignancies in a straightforward, short term, in vivo predictive assay system. Preliminary correlations between in vivo (assay) tumor sensitivity and clinical response have given reasonable concurrence. This crucial point will require further study, with larger numbers of patients, under more rigid conditions. Final validation of this, and other, predictive assays will require a prospective, randomized study in large numbers of patients. Our present prospective study is being continued, therefore, with expansion to a multi-institutional design over a broader geographic area.

CT findings in a nasopharyngeal extramedullary plasmacytoma

We report a case of an extramedullary plasmacytoma arising from the nasopharynx. The computed tomographic appearance of this rare tumor is discussed.

An in vitro model for studying the effects of pharmacological agents on human ciliary beat frequency: effects of lignocaine

1 The effects of lignocaine hydrochloride on ciliary beat frequency (CBF), measured photometrically in vitro, using human epithelium obtained by nasal brushing was studied in 20 healthy subjects. Above lignocaine concentrations of 2.5 x 10(-3) g/ml cilio-inhibition occurred in a dose-dependent manner. Concentrations greater than 2 x 10(-2) g/ml caused ciliostasis. 2 Lignocaine aerosol was sprayed in vivo on the mucosa of one nasal cavity in five healthy subjects and five patients premedicated for bronchoscopy. CBF, measured in vitro in nasal brushings, was not different for treated and untreated sides. 3 Variation of intrinsic CBF with time after nasal brushings were taken was studied in ten normal subjects. No significant change in CBF was found until after 24 h. 4 We conclude that lignocaine hydrochloride, at concentrations three orders of magnitude above drug levels encountered in clinical practice, inhibits human CBF in a dose-dependent manner. Aerosolised lignocaine hydrochloride in doses which produce local nasal mucosal anaesthesia, does not inhibit CBF subsequently measured in vitro. Lignocaine is a suitable local anaesthetic for use at fibreoptic bronchoscopy when samples are being obtained for study of ciliary function. 5 The measurement of CBF in nasal mucosal brushings provides an in vitro model suitable for studying the effects of pharmacological agents on human ciliary activity.

Nasal brushing and measurement of ciliary beat frequency. An in vitro method for evaluating pharmacologic effects on human cilia

Human respiratory tract epithelium suitable for measuring ciliary beat frequency (CBF) may be obtained by nasal brushing. We have used such ciliated epithelium in an in vitro preparation to study the effects on CBF of lidocaine hydrochloride administered topically in vivo before brushing or in vitro after brushing. Beat frequency measured after in vivo administration was unchanged compared to control values while incubating ciliated epithelium in vitro in increasing concentrations of lidocaine resulted in dose-related cilioinhibition. Drug concentrations required to depress ciliary activity in vitro were much higher than those occurring in clinical practice.

The monitoring of saliva drug levels: psychiatric applications

An overview is presented of the status of human saliva as a clinical monitoring medium in medicine and psychiatry. Despite the present controversy about the reliability of saliva lithium levels, an evaluation of the prospects of saliva for other pharmacokinetic estimations as well is recommended. The second part of the paper outlines the authors' attempt to expand the use of saliva monitoring in a depot neuroleptic clinic and a methadone maintenance program. This technique, well accepted by the patient populations, is found useful as a screening tool for drug use and compliance can be checked. It can also be indicated prior to the evaluation of the toxicity of prescribed medication as well as the assessment of drug interaction. On humanitarian, clinical and economical grounds, further investigation of the clinical applications of saliva in psychiatric practice is warranted.

Estrogen receptor values in patients with benign breast disease

Tissue specimens from 55 female patients with benign breast disease were assayed for estrogen receptor. Twenty-one of 55 patients (38%) had tumors which contained significant amounts of estrogen receptor (greater than 10 femtomoles/mg protein). Fibroadenomas possessed estrogen receptor more frequently than fibrocystic disease or other benign breast tumors. Estrogen receptor positivity did not correlate with laterality of the tumor; location or size of the largest nodule. Patients with estrogen receptor positive tumors had a mean age of 26.9 years compared to 36.4 years for patients with estrogen receptor negative tumors (p less than 0.01). Twenty of 46 (43%) premenopausal patients had benign tumors which were estrogen receptor positive compared to zero of 8 postmenopausal patients (p less than 0.05).