Pharmacological Treatments for Anhedonia

Anhedonia - the reduced ability to experience or respond to pleasure - is an important symptom domain for many psychiatric disorders. It is particularly relevant to depression and other mood disorders and it is a diagnostic criterion of a major depressive episode. Developing safe and effective pharmacological interventions for anhedonia is a critical public health need. The current chapter will review the state of the field with respect to both the efficacy of currently available pharmacotherapies for anhedonia and the recent clinical research focusing on new brain targets, including the kappa-opioid receptor and the KCNQ2/3 receptors. The evidence for anti-anhedonic effects of ketamine and psychedelic agents will be reviewed, as well.

Sam68 Enables Metabotropic Glutamate Receptor-Dependent LTD in Distal Dendritic Regions of CA1 Hippocampal Neurons

The transport and translation of dendritic mRNAs by RNA-binding proteins (RBPs) allows for spatially restricted gene expression in neuronal processes. Although local translation in neuronal dendrites is now well documented, there is little evidence for corresponding effects on local synaptic function. Here, we report that the RBP Sam68 promotes the localization and translation of Arc mRNA preferentially in distal dendrites of rodent hippocampal CA1 pyramidal neurons. Consistent with Arc function in translation-dependent synaptic plasticity, we find that Sam68 knockout (KO) mice display impaired metabotropic glutamate-receptor-dependent long-term depression (mGluR-LTD) and impaired structural plasticity exclusively at distal Schaffer-collateral synapses. Moreover, by using quantitative proteomics, we find that the Sam68 interactome contains numerous regulators of mRNA translation and synaptic function. This work identifies an important player in Arc expression, provides a general framework for Sam68 regulation of protein synthesis, and uncovers a mechanism that enables the precise spatiotemporal expression of long-term plasticity throughout neurons.

Opioid system is necessary but not sufficient for antidepressive actions of ketamine in rodents

Slow response to the standard treatment for depression increases suffering and risk of suicide. Ketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, can rapidly alleviate depressive symptoms and reduce suicidality, possibly by decreasing hyperactivity in the lateral habenula (LHb) brain nucleus. Here we find that in a rat model of human depression, opioid antagonists abolish the ability of ketamine to reduce the depression-like behavioral and LHb hyperactive cellular phenotypes. However, activation of opiate receptors alone is not sufficient to produce ketamine-like effects, nor does ketamine mimic the hedonic effects of an opiate, indicating that the opioid system does not mediate the actions of ketamine but rather is permissive. Thus, ketamine does not act as an opiate but its effects require both NMDA and opiate receptor signaling, suggesting that interactions between these two neurotransmitter systems are necessary to achieve an antidepressant effect.

Presynaptic Protein Synthesis Is Required for Long-Term Plasticity of GABA Release

Long-term changes of neurotransmitter release are critical for proper brain function. However, the molecular mechanisms underlying these changes are poorly understood. While protein synthesis is crucial for the consolidation of postsynaptic plasticity, whether and how protein synthesis regulates presynaptic plasticity in the mature mammalian brain remain unclear. Here, using paired whole-cell recordings in rodent hippocampal slices, we report that presynaptic protein synthesis is required for long-term, but not short-term, plasticity of GABA release from type 1 cannabinoid receptor (CB₁)-expressing axons. This long-term depression of inhibitory transmission (iLTD) involves cap-dependent protein synthesis in presynaptic interneuron axons, but not somata. Translation is required during the induction, but not maintenance, of iLTD. Mechanistically, CB₁ activation enhances protein synthesis via the mTOR pathway. Furthermore, using super-resolution STORM microscopy, we revealed eukaryotic ribosomes in CB₁-expressing axon terminals. These findings suggest that presynaptic local protein synthesis controls neurotransmitter release during long-term plasticity in the mature mammalian brain.

Oxytocin improves behavioral and electrophysiological deficits in a novel Shank3-deficient rat

Mutations in the synaptic gene SHANK3 lead to a neurodevelopmental disorder known as Phelan-McDermid syndrome (PMS). PMS is a relatively common monogenic and highly penetrant cause of autism spectrum disorder (ASD) and intellectual disability (ID), and frequently presents with attention deficits. The underlying neurobiology of PMS is not fully known and pharmacological treatments for core symptoms do not exist. Here, we report the production and characterization of a Shank3-deficient rat model of PMS, with a genetic alteration similar to a human SHANK3 mutation. We show that Shank3-deficient rats exhibit impaired long-term social recognition memory and attention, and reduced synaptic plasticity in the hippocampal-medial prefrontal cortex pathway. These deficits were attenuated with oxytocin treatment. The effect of oxytocin on reversing non-social attention deficits is a particularly novel finding, and the results implicate an oxytocinergic contribution in this genetically defined subtype of ASD and ID, suggesting an individualized therapeutic approach for PMS.

DOI:http://dx.doi.org/10.7554/eLife.18904.001

Phelan-McDermid syndrome is a genetic disorder on the autism spectrum that affects how children develop in several ways, with additional symptoms including attention deficits, delays in learning to speak and motor problems. This syndrome is known to be caused by changes in a single gene known as SHANK3 that disrupt communication between brain cells involved in memory and learning. However, we do not know how these changes relate to the symptoms of Phelan-McDermid syndrome.

To understand how genetic changes affect the human brain, researchers often carry out experiments in rats or other small rodents because they have brains that are similar to ours. Harony-Nicolas et al. genetically modified rats to carry changes in the SHANK3 gene that reflect those found in people with Phelan-McDermid syndrome. The rats had disabilities related to those seen in Phelan-McDermid syndrome, including limits in long-term social memory and reduced attention span. They also showed changes in the connections between important parts of the brain. Therefore, studying these rats could help us to understand the link between molecular and cellular changes in the brain and how they affect people with Phelan-McDermid syndrome, and associated symptoms.

Previous studies have shown that a chemical called oxytocin, which is naturally produced by the brain, helps to form bonds between individuals and can cause positive feelings in relation to certain memories. Harony-Nicolas et al. found treating the rats with oxytocin boosted social memory and led to improvements in other symptoms of Phelan-McDermid syndrome. In particular, oxytocin treatment helped to increase the attention span of the rats.

Rats with changes in the SHANK3 gene will be a useful tool for future research into Phelan-McDermid syndrome, particularly in understanding how it affects the connections between brain cells, leading to the symptoms of Phelan-McDermid syndrome. A future challenge will be to find out whether oxytocin has the potential to be developed into a therapy to treat Phelan-McDermid syndrome in humans. Since there is evidence that SHANK3 is involved in other forms of autism, these rats will also be useful in understanding the other ways in which autism can develop.

DOI:http://dx.doi.org/10.7554/eLife.18904.002

Presynaptic Protein Synthesis Is Required for Long-Term Plasticity of GABA Release

Long-term changes of neurotransmitter release are critical for proper brain function. However, the molecular mechanisms underlying these changes are poorly understood. While protein synthesis is crucial for the consolidation of postsynaptic plasticity, whether and how protein synthesis regulates presynaptic plasticity in the mature mammalian brain remain unclear. Here, using paired whole-cell recordings in rodent hippocampal slices, we report that presynaptic protein synthesis is required for long-term, but not short-term, plasticity of GABA release from type 1 cannabinoid receptor (CB₁)-expressing axons. This long-term depression of inhibitory transmission (iLTD) involves cap-dependent protein synthesis in presynaptic interneuron axons, but not somata. Translation is required during the induction, but not maintenance, of iLTD. Mechanistically, CB₁ activation enhances protein synthesis via the mTOR pathway. Furthermore, using super-resolution STORM microscopy, we revealed eukaryotic ribosomes in CB₁-expressing axon terminals. These findings suggest that presynaptic local protein synthesis controls neurotransmitter release during long-term plasticity in the mature mammalian brain.

Abstract P6-07-02: Prediction of oncotype DX® recurrence score using pathology generated equations

BACKGROUND: Oncotype DX® is a quantitative reverse transcription polymerase chain reaction based assay that has been shown to have prognostic and predictive value in estrogen receptor (ER) positive breast cancers. The result is reported as a recurrence score (RS) ranging from 0–100, divided into low risk (<18), intermediate risk (18–30), and high risk (≥31) categories. Prior studies have shown that RS is influenced by ER and progesterone receptor (PR) expression, HER2 status, proliferation index, and tumor grade. Our pilot study showed that RS can be predicted by an equation incorporating standard morpho-immunohistologic variables (referred to as Original Magee Equation; Mod Pathol. 2008;21:1255–1261).

METHODS: Using a dataset of 817 cases, we formulated three additional equations to predict the RS category for an independent set of 255 cases. Three models were built based on different hypotheses and data availability and are represented below.

New Magee Equation 1 (nME1): RS = 15.31385 + Nottingham score*1.4055+ ER H-score*(−0.01924) + PR H-score*(−0.02925) + (0 for HER2 negative, 0.77681 for equivocal, 11.58134 for HER2 positive) + Tumor size*0.78677 + KI67 index*0.13269.

New Magee Equation 2 (nME2): RS = 18.8042+ Nottingham score*2.34123 + ER H-score*(−0.03749) + PR H-score*(−0.03065) + (0 for HER2 negative, 1.82921 for equivocal, 11.51378 for HER2 positive) + Tumor size*0.04267.

New Magee Equation 3 (nME3): RS = 24.30812+ ER H-score*(−0.02177) + PR H-score*(−0.02884) + (0 for HER2 negative, 1.46495 for equivocal, 12.75525 for HER2 positive) + KI-67*0.18649.

RESULTS: The concordance between the risk category of oncotype DX® and our equations was 55.8%, 59.4%, and 54.4% for nME1, nME2, and nME3 respectively. With exclusion of the intermediate risk categories for both the actual RS and estimated RS, the concordance for each equation increased to more than 95%, reflecting the very low two step discordance (100% {76/76}, 98.6% {75/76}, and 98.7% {79/80} for nME1, nME2, and nME3 respectively). Even when the estimated RS fell in the intermediate category with any of the equations, the actual RS was either intermediate or low in more than 85% of the cases. The Pearson correlation coefficient between estimated and actual RS was similar for each of the equations (0.61661, 0.60386 and 0.59407 for nME1, nME2 and nME3, respectively).

CONCLUSIONS: Any of the 3 equations can be used to estimate the RS depending on available data. If the estimated RS is clearly high or low, the oncologists should not expect a dramatically different result from oncotype DX®, and the oncotype DX® test may not be needed. Conversely, an oncotype DX® result that is dramatically different from what is expected based on standard morpho-immunohistologic variables should be thoroughly investigated.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-02.

Homeostatic regulation of MeCP2 expression by a CREB-induced microRNA

Both increases and decreases in methyl CpG-binding protein 2 (MeCP2) levels cause neurodevelopmental defects. We found that MeCP2 translation is regulated by microRNA 132 (miR132). Block of miR132-mediated repression increased MeCP2 and brain-derived neurotrophic factor (BDNF) levels in cultured rat neurons and the loss of MeCP2 reduced BDNF and miR132 levels in vivo. This feedback loop may provide a mechanism for homeostatic control of MeCP2 expression.

Role reversal: the regulation of neuronal gene expression by microRNAs

In a similar fashion to transcription factors, non-coding RNAs can be essential regulators of gene expression. The largest class of non-coding RNAs is the microRNAs. These approximately 22 nt double-stranded RNA molecules can repress translation or target mRNA degradation. There has been a surge of research in the past year stimulated by the recent availability of specialized techniques, both in vitro and in silico, for predicting and characterizing microRNAs. The accumulating evidence suggests that microRNAs are ubiquitous regulators of gene expression during development. The combined actions of microRNAs and transcription factors are able to tune the expression of proteins on a global level in a manner that cannot be achieved by transcription factors alone.

A cAMP-response element binding protein-induced microRNA regulates neuronal morphogenesis

MicroRNAs (miRNAs) regulate cellular fate by controlling the stability or translation of mRNA transcripts. Although the spatial and temporal patterning of miRNA expression is tightly controlled, little is known about signals that induce their expression nor mechanisms of their transcriptional regulation. Furthermore, few miRNA targets have been validated experimentally. The miRNA, miR132, was identified through a genome-wide screen as a target of the transcription factor, cAMP-response element binding protein (CREB). miR132 is enriched in neurons and, like many neuronal CREB targets, is highly induced by neurotrophins. Expression of miR132 in cortical neurons induced neurite outgrowth. Conversely, inhibition of miR132 function attenuated neuronal outgrowth. We provide evidence that miR132 regulates neuronal morphogenesis by decreasing levels of the GTPase-activating protein, p250GAP. These data reveal that a CREB-regulated miRNA regulates neuronal morphogenesis by responding to extrinsic trophic cues.

Microsecond pulsed optical parametric oscillator pumped by a Q-switched fiber laser

We report on what is to our knowledge the first optical parametric oscillator (OPO) pumped by microsecond pulses from a wavelength-tunable solid-state laser. The singly resonant OPO (SRO) is based on a periodically poled LiNbO3 crystal and pumped with 2.1-micros-long pulses from an actively Q-switched Yb fiber laser. At an average fiber laser power of 3.6 W, the SRO generates 1.9-micros-long pulses with a repetition rate of 25 kHz and an average power of 560 mW at 3360 nm. The SRO was tuned from 1518 to 1634 nm (signal) and from 3145 to 3689 nm (idler) via the crystal temperature and poling period. By all-electronic tuning of the fiber laser wavelength over 19 nm, tuning of the mid-infrared idler wavelength over 195 nm was achieved.

Rapidly tunable continuous-wave optical parametric oscillator pumped by a fiber laser

We report on rapid, all-electronically controlled wavelength tuning of a continuous-wave (cw) optical parametric oscillator (OPO) pumped by an ytterbium fiber laser. The OPO is singly resonant for the signal wave and consists of a 40-mm-long periodically poled lithium niobate crystal in a four-mirror ring cavity. By tuning of the fiber-laser wavelength over 33 nm through an intracavity acousto-optic tunable filter, the OPO idler wavelength is tuned from 3160 to 3500 nm in 330 micros, corresponding to an idler frequency-tuning speed of 28 THz/ms. At a fiber-laser power of 6.6 W at 1074 nm, the singly resonant OPO generates 1.13-W cw idler radiation at 3200 nm.

Wide wavelength tuning of an optical parametric oscillator through electro-optic shaping of the gain spectrum

We present a novel technique for tuning an optical parametric oscillator (OPO) through electro-optically induced shape variations of the parametric gain spectrum in quasi-phase-matched lithium niobate (LN). The diode-pumped, triply resonant continuous-wave OPO is based on a 58-mm-long LN crystal that consists of three equally long sections, the outer sections being periodically poled with a 50% duty cycle. The center section is single-domain material and serves as a tunable phase shifter through the electro-optic effect. By application of a voltage of up to 1230 V, the OPO signal and idler wavelengths are tuned over 102 nm from 1560 to 1660 nm, in good agreement with theory.

Fiber-laser-pumped continuous-wave singly resonant optical parametric oscillator

We report on what is to our knowledge the first continuous-wave (cw) optical parametric oscillator (OPO) that is pumped by a tunable fiber laser. The OPO is singly resonant for the signal wave and consists of a 40-mm-long periodically poled LiNbO(3) crystal in a four-mirror ring cavity. At a pump power of 8.3 W provided by the wavelength-tunable Yb-doped fiber laser, the singly resonant OPO generates 1.9 W of 3200-nm cw idler radiation. The singly resonant OPO was tuned from 1515 to 1633 nm (signal) and from 3057 to 3574 nm (idler) by means of the crystal temperature and poling period. We obtained a wide idler tuning range, from 2980 to 3700 mn, by tuning the wavelength of the fiber laser from 1032 to 1095 nm.

2.5-GHz repetition-rate singly resonant optical parametric oscillator synchronously pumped by a mode-locked diode oscillator amplifier system

We report on an optical parametric oscillator (OPO) that is synchronously pumped directly by a diode laser. This laser is an actively mode-locked master-oscillator power-amplifier system that produces 20-ps pulses at 927 nm with a repetition rate of 2.5 GHz and an average power of 0.9 W. The OPO, which is a singly resonant device based on periodically poled lithium niobate, generates 7.8-ps pulses. The OPO threshold is 300 mW of average pump power, and the maximum average idler output power is 78 mW at a wavelength of 2100 nm. By changing the crystal temperature we can wavelength tune the output in the ranges 1530-1737 nm (signal) and 1986-2348 nm (idler). Rapid wavelength tuning of the OPO over 46 nm (signal) and 74 nm (idler) is achieved through tuning the cavity length over 28 microm by use of a piezoelectric transducer.

Diode-pumped singly resonant continuous-wave optical parametric oscillator with wide continuous tuning of the near-infrared idler wave

We demonstrate wide, continuous tuning of the single-frequency idler wave of a cw singly resonant optical parametric oscillator (SRO). The SRO consists of a periodically poled LiNbO(3) crystal for quasi-phase matching in a four-mirror signal-resonant ring cavity. The SRO, excited by 2.25 W of 924-nm radiation from an InGaAs diode laser, generates as much as 200 mW of single-frequency 2.1-mum idler radiation. We tune the idler frequency continuously within a range as large as 56 GHz by changing the wavelength of the diode pump laser. The versatility of this continuously tunable single-frequency infrared source is demonstrated by recording of N(2)O rovibrational absorption lines near 2.1 mum.

EGO-1 is related to RNA-directed RNA polymerase and functions in germ-line development and RNA interference in C. elegans

BACKGROUND

Cell-fate determination requires that cells choose between alternative developmental pathways. For example, germ cells in the nematode worm Caenorhabditis elegans choose between mitotic and meiotic division, and between oogenesis and spermatogenesis. Germ-line mitosis depends on a somatic signal that is mediated by a Notch-type signaling pathway. The ego-1 gene was originally identified on the basis of genetic interactions with the receptor in this pathway and was also shown to be required for oogenesis. Here, we provide more insight into the role of ego-1 in germ-line development.

RESULTS

We have determined the ego-1 gene structure and the molecular basis of ego-1 alleles. Putative ego-1 null mutants had multiple, previously unreported defects in germ-line development. The ego-1 transcript was found predominantly in the germ line. The predicted EGO-1 protein was found to be related to the tomato RNA-directed RNA polymerase (RdRP) and to Neurospora crassa QDE-1, two proteins implicated in post-transcriptional gene silencing (PTGS). For a number of germ-line-expressed genes, ego-1 mutants were resistant to a form of PTGS called RNA interference.

CONCLUSIONS

The ego-1 gene is the first example of a gene encoding an RdRP-related protein with an essential developmental function. The ego-1 gene is also required for a robust response to RNA interference by certain genes. Hence, a protein required for germ-line development in C. elegans may be a component of the RNA interference/PTGS machinery.

Singly resonant continuous-wave optical parametric oscillator pumped by a diode laser

We report on what is believed to be the first singly resonant cw optical parametric oscillator (SRO) that is directly pumped by a diode laser. The SRO consists of a 38-mm-long periodically poled LiNbO(3) crystal in a four-mirror signal-resonant ring cavity. Pumped by 2.5 W of 925-nm diode-laser radiation, the SRO generates 480 mW of single-frequency idler radiation at 2.1mum . The wavelengths of the signal and the idler output are tuned in the ranges of 1.55 to 1.70mum and 2.03 to 2.29mum, respectively, by tuning the wavelength of the diode laser from 924.0 to 925.4 nm.

Periodically poled potassium niobate for second-harmonic generation at 463 nm

We report on the fabrication and characterization of quasi-phase-matched potassium niobate crystals for second-harmonic generation. Periodic 30-mum -pitch antiparallel ferroelectric domains are fabricated by means of poling in an electrical field. Both birefrigence and periodic phase shift of the generated second harmonic contribute to phase matching when the d(31) nonlinear optical tensor element is used. 3.8 mW of second-harmonic radiation at 463 nm is generated by frequency doubling of the output of master-oscillator power-amplifier diode laser in a 5-mm-long crystal. The measured effective nonlinear coefficient is 3.7pm/V. The measured spectral acceptance bandwidth of 0.25 nm corresponds to the theoretical value.

Diode-pumped continuous-wave widely tunable optical parametric oscillator based on periodically poled lithium tantalate

We report on a diode-laser pumped cw optical parametric oscillator (OPO) based on quasi-phase-matched periodically poled lithium tantalate. Pumped by the 2.3-W single-frequency, nearly diffraction-limited 925-nm output of an InGaAs diode master-oscillator power amplifier, the pump and signal resonant OPO generates a single-frequency idler wave with an output of as much as 244 mW. The wavelengths of the signal and idler waves are widely tunable in the range 1.55-2.3mum by use of different poling periods (27.3 to 27.9mum) and by variation of the crystal temperature in the range 70-190 degrees C.

trans-2-phenylcyclopropylamine is a substrate for and inactivator of horseradish peroxidase

Horseradish peroxidase (HRP) is well known for mediating the electron-transfer oxidation of electron-rich aromatic 'donors' such as phenols and anilines, but has not been described to oxidize aliphatic amines. We here confirm the inability of HRP to oxidize typical aliphatic amines, even those which would exist significantly as free bases at the operative pH. In contrast, trans-2-phenylcyclopropylamine (2-PCPA) is both a substrate (turnover product is cinnamaldehyde) and a time-dependent inactivator of HRP. These activities of 2-PCPA are consistent with either a concerted or rapid sequential one-electron-oxidation/ring-opening to give an intermediate capable of covalent binding to the enzyme. 2-PCPA is the first known example of a simple aliphatic amine which serves as a substrate for HRP under turnover conditions.

Haemoprotein-mediated metabolism of enamines and the possible involvement of one-electron oxidations

1. Microsomal metabolism of 1-benzylpiperidine (1-BP), its cis-2,6-dimethyl (cis-2,6-DMBP), 4,4-dimethyl (4,4-DMBP), and alpha, alpha-dimethyl (alpha, alpha-DMBP) analogues, and phencyclidine (PCP) has been studied to assess the involvement of P450 oxidation of the enamine tautomers of the initial endocyclic iminium metabolites. 2. The selective prevention by cyanide of the metabolite production of 1-benzyl-3-piperidone but not 1-benzyl-3-piperidinol from 1-BP is consistent with the enamine as the source of the 3-one metabolite. 3. The parent amines and particularly the independently prepared iminium species induced a pattern of metabolism-dependent irreversible inactivation of P450 benz-phetamine demethylase activity, consistent with involvement of enamine C-3 oxidation in the inactivation process. 4. Substrate activity of the endocyclic enamines and alpha-aminoketones (presumably the enol-enamine tautomers) for horseradish peroxidase under conditions where simple aliphatic amines display no activity is consistent with metabolic one-electron oxidations of the enamines.

Incidence and pattern of jaundice in healthy breast-fed infants during the first month of life

The incidence and pattern of jaundice in 155 normal, full-term, breast-fed, white infants was examined. Infants were screened for jaundice on Days 2, 3, 5, 7, 9, 11, and 13 following birth using transcutaneous bilirubinometry (TcB). By Day 3, 49.7% of the infants were classified as jaundiced (> 10 mg/dl). Infants with low TcB indices on Days 2, 3, and 5 never developed jaundice as indicated by elevated TcB indices on Days 7, 9, 11, and 13. Hence, it may be possible to target infants at risk for severe jaundice prior to discharge. The observed rate of 10.3% for breast-milk jaundice (jaundice present at Day 13) is significantly higher than the highest reported rate of 2.4% (z = 6.43, p < .01). Furthermore, the pattern of jaundice in these infants does not appear to have two peaks, indicating that it is not possible to distinguish between exaggerated physiologic jaundice and breast-milk jaundice using TcB.

Transcutaneous bilirubinometer: intermeter reliability

This study examined intermeter reliability on two transcutaneous bilirubinometers on 30 white prephototherapy infants between 36 and 42 weeks' gestation with birthweights greater than 2500 g. All infants were screened with both meters, on the forehead, within a 5-minute period. Meter readings were taken within 30 minutes following infant heelstick for serum bilirubin. The Pearson correlations between serum bilirubin and jaundice meter measurements were .75 for meter 1 and .76 for meter 2. The correlation between jaundice meter indices from the two meters was .87, leaving 13% of the variance in one meter not accounted for by the correlation with the other meter. An examination of the differences between the two meters revealed that in the upper range (greater than or equal to 16) meter 1 was always higher than meter 2 by, on the average, 2.6 points (SD = 1.3). In readings of 15 or less, the differences between the meters were inconsistent. Additionally, in 16 of 30 cases, the action levels from the two meters led to the same conclusion; in the remaining 14 cases, meter 1 gave a positive reading (indicating the need to determine serum bilirubin) while meter 2 gave an equivocal reading (indicating user discretion in deciding whether serum bilirubin should be determined). These data indicate that each meter should be individually evaluated to determine action indices, and that jaundice meters should not be used interchangeably on the same infant.

[Hemorrhagic internal pachymeningitis. A clinical study of 131 cases]

Between 1980 and 1985, 131 patients suffering from haemorrhagic internal pachymeningitis had undergone surgery. Mean patient age was 59 years (range: 16-90 years). Operation technique was burr-hole craniotomy with closed-system drainage in 124 cases. In five cases primary, in 24 cases secondary removal of the capsule was performed. An Ommaya reservoir was implanted in eight cases. All patients were re-examined after an average of six months and classified into six groups according to the neurological findings. Comparison of initial findings and final results showed an improvement in the patients' condition in 83 cases (63%). There was no change in 20 patients (15%) and deterioration in seven (5%). Twenty-one patients (16%) died during the observation period.

An analysis of bowel perforation in patients with intussusception

A barium colon examination is recommended for the diagnosis and reduction of intussusception in children, except when bowel perforation is evident either radiographically or clinically. In our experience and contrary to recent reports neither radiographic evidence of bowel obstruction nor an age of less than six months is a contraindication. We reviewed 40 patients diagnosed as having had intussusception and found five children aged more than six months with perforations discovered at operation. Three of the five children had plain radiographic findings of small bowel obstruction as did nine other children. In four of the 12 children with evidence of small bowel obstruction a successful hydrostatic reduction of the intussusception was carried out. Barium studies were performed for diagnosis and therapy in eight children with ileo-colic intussusception aged six months or less, four of whom had evidence of small bowel obstruction. In five, including two with obstruction, reduction of the intussusception was successful. The major contraindication to barium examination is radiographic or clinical evidence of perforation.

Cyclophosphamide and dimethylsulfoxide in the treatment of squamous carcinoma of the lung. Therapeutic efficacy, toxicity, and pharmacokinetics

To determine whether dimethylsulfoxide (DMSO) can potentiate antitumor activity of cyclophosphamide (CYC) in patients with squamous cell carcinoma of the lung, 14 patients were treated with 5 l of a 5% or 6% DMSO solution PO over 3 days and 1,500 mg CYC/m2 IV as a 60-min infusion on the third day of treatment. Serial blood, CSF, and urine samples were collected to assess the pharmacokinetics of CYC. Courses were repeated every 3-4 weeks. No antitumor responses were observed. Toxicity was mainly hematologic and similar to that of CYC alone. There was one death from infection during granulocytopenia. Nonhematologic toxicity was moderate to severe and included nausea (14 patients) and vomiting (five patients). The plasma pharmacokinetics of CYC in this study are similar to previously reported results for CYC alone, but the 24-h urinary excretion of CYC in our study is much lower than previously reported. Further studies in tumors more responsive to CYC may be warranted.

Carcinoma of the lung and cigarette smoking. Effect on serum ribonuclease activity

Serum ribonuclease levels were determined in 54 patients with lung carcinoma, 74 long-term cigarette smokers, and 172 nonsmokers. The mean serum ribonuclease level was significantly higher in patients with lung carcinoma and long-term smokers compared with healthy nonsmokers (P less than .001). The serum ribonuclease activity level was not related to chronological age, sex, or race of the smoker or nonsmoker population. Forty (75%) of 53 patients with lung cancer and 49 (66%) of 74 smokers had elevated serum ribonuclease levels compared with 13 (7%) of 179 nonsmoker healthy controls (P less than .001). The highest incidence of elevation was noted in patients with epidermoid carcinoma (95%).