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Many studies exist of thalamocortical synapses in primary sensory cortex, but much less in known about higher-order thalamocortical projections to higher-order cortical areas. We begin to address this gap using genetic labeling combined with large volume serial electron microscopy (i.e., "connectomics") to study the projection from the thalamic posterior medial nucleus to the secondary somatosensory cortex in a mouse. We injected into this thalamic nucleus a cocktail combining a cre-expressing virus and one expressing cre-dependent ascorbate peroxidase that provides an electron dense cytoplasmic label. This "intersectional" viral approach specifically labeled thalamocortical axons and synapses, free of retrograde labeling, in all layers of cortex. Labeled thalamocortical synapses represented 14% of all synapses in the cortical volume, consistent with previous estimates of first-order thalamocortical inputs. We found that labeled thalamocortical terminals, relative to unlabeled ones: were larger, were more likely to contain a mitochondrion, more frequently targeted spiny dendrites and avoided aspiny dendrites, and often innervated larger spines with spine apparatuses, among other differences. Furthermore, labeled terminals were more prevalent in layers 2/3 and synaptic differences between labeled and unlabeled terminals were greatest in layers 2/3. The laminar differences reported here contrast with reports of first-order thalamocortical connections in primary sensory cortices where, for example, labeled terminals were larger in layer 4 than layers 2/3 (Viaene et al., 2011a). These data offer the first glimpse of higher-order thalamocortical synaptic ultrastructure and point to the need for more analyses, as such connectivity likely represents a majority of thalamocortical circuitry., (© 2020 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Objective: To evaluate the effectiveness of nurse-led telephone follow-up (TFU) for patients with stage-I endometrial cancer., Design: Multicentre, randomised, non-inferiority trial., Setting: Five centres in the North West of England., Sample: A cohort of 259 women treated for stage-I endometrial cancer attending hospital outpatient clinics for routine follow-up., Methods: Participants were randomly allocated to receive traditional hospital based follow-up (HFU) or nurse-led TFU., Main Outcome Measures: Primary outcomes were psychological morbidity (State Trait Anxiety Inventory, STAI-S) and patient satisfaction with the information provided. Secondary outcomes included patient satisfaction with service, quality of life, and time to detection of recurrence., Results: The STAI-S scores post-randomisation were similar between groups [mean (SD): TFU 33.0 (11.0); HFU 35.5 (13.0)]. The estimated between-group difference in STAI-S was 0.7 (95% confidence interval, 95% CI -1.9 to 3.3); the confidence interval lies above the non-inferiority limit (-3.5), indicating the non-inferiority of TFU. There was no significant difference between groups in reported satisfaction with information (odds ratio, OR 0.9; 95% CI 0.4-2.1; P = 0.83). Women in the HFU group were more likely to report being kept waiting for their appointment (P = 0.001), that they did not need any information (P = 0.003), and were less likely to report that the nurse knew about their particular case and situation (P = 0.005)., Conclusions: The TFU provides an effective alternative to HFU for patients with stage-I endometrial cancer, with no reported physical or psychological detriment. Patient satisfaction with information was high, with similar levels between groups., Tweetable Abstract: ENDCAT trial shows effectiveness of nurse-led telephone follow-up for patients with stage-I endometrial cancer., (© 2016 Royal College of Obstetricians and Gynaecologists.)

Gamma-hydroxybutyric acid (GHB) is gaining popularity as a drug of abuse. Reports of toxicity and lethality associated with GHB use have increased. This survey study was designed to identify patterns of GHB use, its effects, and withdrawal syndrome. A survey inquiring about the effects of GHB was administered to 42 users. The results showed that GHB was used to increased feelings of euphoria, relaxation, and sexuality. Adverse effects occurred more frequently in daily users and polydrug users than in occasional GHB users. Loss of consciousness was reported by 66%, overdose by 28%, and amnesia by 13% of participants during GHB use and by 45% after GHB use. Three daily users developed a withdrawal syndrome that presented with anxiety, agitation, tremor, and delirium. Participants described GHB intoxication as having similarities to sedative-hypnotic or alcohol intoxication. Regular use has been shown to produce tolerance and dependence. Participants dependent on GHB reported using multiple daily doses around the clock. High frequency users appeared at the greatest risk for developing withdrawal delirium and psychosis after abrupt discontinuation of GHB use.

To compare the efficacy and acceptability of conventional intravenous sedation with patient-controlled inhalational isodesox, 57 women undergoing outpatient oocyte recovery were randomly allocated to receive isodesox by face mask, while 55 women were given intravenous fentanyl and midazolam. Women's satisfaction with pain relief, peroperative pain, clouding of memory and the surgeons' assessment of operating conditions were evaluated. Thirty-eight women in the inhalation group (67%) and 41 (75%) women in the intravenous group were 'very satisfied' with their analgesia (p = 0. 41). The mean (SD) pain score in women given isodesox was 46.8 (34. 7), while in the intravenous group it was 34.1 (21.3) (p = 0.02). Oxygen saturation levels < 94% were recorded in one woman using isodesox and in 16 (29%) women given intravenous analgesia. Despite higher pain scores, in comparison with the conventional analgesia, patient-controlled isodesox offers a safer method of pain relief with comparable satisfaction rates.

Objectives: Recent NHS changes have included an increasing emphasis on primary care settings, and hence community needs assessment. This has led to suggestions that medical education should become more community-oriented if today's medical students are to become effective medical practitioners. Recent curriculum reforms in a number of medical schools frequently involve a more student-centred approach, which encourages students to learn by intellectual discovery and critical thinking. We describe one such exercise in community diagnosis that has been developed in Glasgow's new undergraduate medical curriculum., Design: The exercise has been developed as three teaching sessions, each with specific learning objectives. The first session explores the strengths and weaknesses of routine statistics, and reveals the lack of information regarding individual's and community's health and health care needs. The second session is a community-based rapid participatory appraisal arranged by general practitioners. Students interview patients, carers, and local key informants and health care professionals about their perceptions of health and health needs. In the final campus-based session, students combine and present their findings. Development included two pilot exercises involving detailed evaluation., Setting: University of Glasgow., Subjects: Medical students., Results: Students valued the contrasting perspectives and information provided by different sources. After completing the three sessions, most students and tutors considered it an interesting, enjoyable and educational experience., Conclusions: This innovative community-oriented teaching programme gave students some insight into how health, morbidity and mortality are measured, why these might vary between different communities, and how different community members' perspectives might differ regarding perceived health and social needs.

1. Heterocyclic amines are formed in parts per billion levels when meat is cooked. 2. The heterocyclic amines MeIQx and PhIP are efficiently absorbed into the systemic circulation after ingestion of cooked food. 3. We have shown that MeIQx and PhIP, both in vitro and in vivo, are substrates for human hepatic CYP1A2, which exclusively and efficiently catalyses their conversion to genotoxic hydroxylamines. 4. MeIQx and PhIP are promutagens. MeIQx is a very powerful bacterial mutagen whereas PhIP is a more potent mammalian cell mutagen. Using a mammalian cell target gene, hprt, we have shown that PhIP induces a characteristic mutational 'fingerprint'. 5. MeIQx and PhIP are carcinogenic in bioassays. The PhIP mutational 'fingerprint' has been detected in the Apc gene of 5/8 colonic tumours induced by PhIP in rats.

1. Mono(ADP-ribosyl)transferase activity has been identified on the external surface of human polymorphonuclear neutrophil leucocytes (PMNs). The enzyme is released from the plasma membrane by phosphoinositide-specific phospholipase C, suggesting a glycosylphosphatidylinositol (GPI) linkage of the enzyme to the plasma membrane. Partial sequence of cDNA encoding the enzyme suggests that it is identical to the GPI-linked mono(ADP-ribosyl)-transferase identified previously on human skeletal muscle. 2. A panel of inhibitors of mono(ADP-ribosyl)transferase (including vitamins K1 and K3, novobiocin and nicotinamide) showed a rank order of inhibitory potency similar to that described for other mono(ADP-ribosyl)transferases. Furthermore, the mono(ADP-ribosyl)ation of agmatine was inhibited also by diethylamino (benzylidineamino)guanidine (DEA-BAG), another substrate of the enzyme related structurally to arginine. 3. There was a close linear correlation between the IC50 values for inhibition of mono(ADP-ribosyl)ation of agmatine by DEA-BAG or the enzyme inhibitors and their IC50 values for inhibition of receptor-dependent polymerization of cytoskeletal actin and chemotaxis. 4. These results suggest a role for mono(ADP-ribosyl)transferase in the transduction pathway involved in receptor-dependent re-alignment of the cytoskeleton during neutrophil chemotaxis.

1. Mass spectrometry (MS) has played a vital role in the research of the department of clinical pharmacology for over 25 years. 2. MS has been used for trace analysis of endogenous compounds and xenobiotics in plasma and urine, and also for a wide range of structural studies. 3. Examples of current applications are reported, including data from gas chromatography-mass spectrometry (GC-MS) assays for mevalonic acid, the identification of an antibiotic produced by Pseudomonas aeruginosa which is active against Helicobacter pylori, high pressure liquid chromatography (h.p.l.c)-electropray MS studies on steroid sulphates, the aspergillus ciliotoxin, gliotoxin, and ADP ribosyltransferase activity in human polymorphonuclear neutrophil leucocytes (PMNs). The value of electrospray MS in the molecular weight determination of proteins is exemplified by the analysis of human serum amyloid component P.

1. Furafylline (1,8-dimethyl-3-(2'-furfuryl)methylxanthine) is a methylxanthine derivative that was introduced as a long-acting replacement for theophylline in the treatment of asthma. Administration of furafylline was associated with an elevation in plasma levels of caffeine, due to inhibition of caffeine oxidation, a reaction catalysed by one or more hydrocarbon-inducible isoenzymes of P450. We have now investigated the selectivity of inhibition of human monooxygenase activities by furafylline. 2. Furafylline was a potent, non-competitive inhibitor of high affinity phenacetin O-deethylase activity of microsomal fractions of human liver, a reaction catalysed by P450IA2, with an IC50 value of 0.07 microM. 3. Furafylline had either very little or no effect on human monooxygenase activities catalysed by other isoenzymes of P450, including P450IID1, P450IIC, P450IIA. Of particular interest, furafylline did not inhibit P450IA1, assessed from aryl hydrocarbon hydroxylase activity of placental samples from women who smoked cigarettes. 4. It is concluded that furafylline is a highly selective inhibitor of P450IA2 in man. 5. Furafylline was a potent inhibitor of the N3-demethylation of caffeine and of a component of the N1- and N7-demethylation. This confirms earlier suggestions that caffeine is a selective substrate of a hydrocarbon-inducible isoenzyme of P450 in man, and identifies this as P450IA2. Thus, caffeine N3-demethylation should provide a good measure of the activity of P450IA in vivo in man. 6. Although furafylline selectively inhibited P450IA2, relative to P450IA1, in the rat, this was at 1000-times the concentration required to inhibit the human isoenzyme, suggesting a major difference in the active site geometry between the human and the rat orthologues of P50IA2.

1. It has been suggested that poor metabolisers of debrisoquine are at reduced risk of developing lung cancer from smoking cigarettes. This has been investigated in 82 patients with established cancer of the lung. 2. The frequency of poor metaboliser subjects was not different from that in the normal population. 3. There was no tendency for subjects with lung cancer to metabolise debrisoquine more rapidly than non-cancer subjects. 4. It is concluded that debrisoquine metabolic phenotype is not a good predictor of risk of developing lung cancer in the population at large.

The mammalian lateral geniculate nucleus seems organized to gate or control the gain of retinogeniculate transmission, the result of which is then relayed to the visual cortex. We have performed in vivo intracellular studies of retinogeniculate transmission along these retino-geniculo-cortical pathways in cats by recording the retinally evoked excitatory postsynaptic potential (EPSP) in geniculate neurons. In cats, these pathways are organized into two parallel and functionally distinct channels, the X and Y pathways. We found that nearly all geniculate X cells display a fairly conventional voltage dependency for their retinally evoked EPSPs, because the amplitudes of these EPSPs decrease fairly linearly with membrane depolarization as the EPSP reversal potential is approached. Rare X cells and all Y cells, however, show an unconventional response: over a wide range of membrane potentials, their EPSP amplitudes increase with membrane depolarization. This increase does not result from alterations in neuronal input resistance and instead seems due to changes in synaptic conductance. The underlying cause of this voltage dependency remains to be determined. None the less, it does afford an interesting means by which retinogeniculate transmission can be gated, since non-retinal inputs (e.g. corticogeniculate axons) that can control a relay Y cell's membrane potential can also modulate the cell's EPSP amplitude.

1 A method for the assay of debrisoquine 4-hydroxylase activity in vitro by microsomal fractions of human liver is described. The assay utilises gas chromatography-mass spectrometry with d9-4-hydroxydebrisoquine as internal standard. 2 The limit of detection of 4-hydroxydebrisoquine was 2 ng ml -1 and the coefficient of variation was 4.4%. 3 Debrisoquine 4-hydroxylase activity was linear with protein to concentrations above 2.1 mg ml -1 and with incubation times of at least 15 min. 4 Debrisoquine 4-hydroxylase is a microsomal enzyme with a requirement for NADPH. Activity was inhibited by carbon monoxide. It is concluded that the activity is catalysed by cytochrome P-450. 5 In three samples of human liver the mean value for Vmax of debrisoquine 4-hydroxylase activity was 69.9 +/- 14.3 pmol mg -1 min -1 and for Km it was 130 +/- 24 microM. 6 The only variable from smoking status, alcohol ingestion, sex of the patients, source of liver sample and presence of liver disease that had a significant effect on 4-hydroxylation of debrisoquine was the presence of liver disease. This was associated with a decrease in enzyme activity.

A case is reported of tension pneumothorax following left subclavian venous cannulation for placement of a fibreoptic pulmonary artery flotation catheter. Mixed venous oxygen saturation was continuously monitored and a fall in this was the first indication of the problem. Observations on the cardiovascular consequences of tension pneumothorax were made and followed during its treatment. The value of continuous monitoring of mixed venous oxygen saturation in the early detection of haemodynamic disturbances is emphasized.

Twenty-eight samples of human liver have been characterised for cytochrome P-450 content, aldrin epoxidase, debrisoquine 4-hydroxylase and bufuralol 1'-hydroxylase activities. Evidence is presented here and elsewhere that bufuralol 1'-hydroxylase and debrisoquine 4-hydroxylase are activities catalysed by the same form of cytochrome P-450 in man, and that this form is different from that catalysing the epoxidation of aldrin. Attempts to phenotype liver samples in vitro, in the absence of any metabolic data in vivo for debrisoquine 4-hydroxylation status, met with limited success. A combination of enzyme assays will most probably be required in any such phenotyping of human liver samples.

The half-life of antipyrine has been estimated from saliva samples in ten subjects by a gas chromatographic method. Half-life, apparent volume of distribution and total body clearance estimated from saliva and plasma concentrations of antipyrine are not significantly different. The concentration of antipyrine in saliva is independent of flow rate within the range expected in healthy subjects in response to mechanical and sapid stimuli. Antipyrine estimation in saliva could facilitate many areas of phaamacokinetic research limited by the difficulty of obtaining serial plasma samples.

Phenacetin O-deethylase activity was impaired, both in vivo and in vitro, in poor metabolisers of debrisoquine, consistent with the work of others. No impairment was observed in the oxidation of acetanilide, amylobarbitone or antipyrine in the PM phenotype. There was a good correlation (r = 0.804) between the high affinity component of phenacetin O-deethylase and debrisoquine 4-hydroxylase activities. No such correlation was observed with the low affinity component of phenacetin O-deethylase activity. Although debrisoquine was a competitive inhibitor of phenacetin O-deethylase activity, phenacetin was without effect on debrisoquine 4-hydroxylation. There was also marked differences in the effects of sparteine, guanoxan and alpha-naphthoflavone on the two activities. Cigarette smoking was associated with a significant, two-fold, increase in phenacetin O-deethylase activity whilst debrisoquine 4-hydroxylase activity was not affected. It is concluded that the high affinity component of phenacetin O-deethylase and debrisoquine 4-hydroxylase activities are catalysed by different isozymes of cytochrome P-450 but that these are most probably regulated by closely linked genes.

1 The metabolism of antipyrine to its three main oxidative metabolites, 4-hydroxyantipyrine, 3-hydroxymethylantipyrine and norphenazone was investigated in vivo and in vitro in separate groups of subjects with normal hepatic function and in the same group of patients with suspected liver disease. 2 The rank order for the rate of formation of the three metabolites of antipyrine was similar in vivo and in vitro. 3 There was no significant correlation between the rates of formation of any pair of antipyrine metabolites either in vivo or in vitro. 4 Despite this there was a significant correlation between the in vivo and in vitro rates for formation of each of the three metabolites in the same group of patients. 5 It is concluded that determination of rates of formation of antipyrine metabolites from their excretion in urine provides an indication of the activity of the enzymes involved in their formation.

The dose of combination chemotherapy in Hodgkin's disease is commonly calculated from a formula based on the body surface area. A method is described for measuring the intensity of combination chemotherapy actually received compared to the calculated planned dose. The technique is applied to 56 patients receiving mustine, vinblastine, procarbazine and prednisolone, but would also be suitable for other cytotoxic regimens. The planned dosage intensity had to be significantly reduced in over half of the patients because of marrow toxicity. Splenectomized patients received a higher dose intensity than those in whom the procedure was not performed.

Quinidine and its diastereoisomer quinine were tested in vitro for their effect on the 4-hydroxylation of debrisoquine, the O-deethylation of phenacetin and the 1'-hydroxylation of bufuralol, by human liver microsomal samples; quinidine was studied for its effect on debrisoquine 4-hydroxylation in vivo. Quinidine was a potent inhibitor of the 4-hydroxylation of debrisoquine and the 1'-hydroxylation of bufuralol, with IC50 values of 0.7 and 0.2 microM, being around 100 times more potent in this respect than quinine. Very much higher (1000-fold) levels of quinidine were required to inhibit the O-deethylation of phenacetin, being rather less potent in this than quinine. Eight subjects were phenotyped for their debrisoquine oxidation status and found to be extensive metabolisers (EM). They were tested again after the co-administration of 50 mg of quinidine with the debrisoquine. The concomitant administration of quinidine increased the metabolic ratios (MRs) by a mean of 26-fold. The effects of quinidine at a dose of only 50 mg, on the metabolism of a new drug in EM subjects may prove a useful method of assessing the contribution of the debrisoquine 4-hydroxylase isozyme to the elimination of the drug tested.