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By combining DNA nanotechnology and high-bandwidth single-molecule detection in nanopipets, we demonstrate an electric, label-free hybridization sensor for short DNA sequences (<100 nucleotides). Such short fragments are known to occur as circulating cell-free DNA in various bodily fluids, such as blood plasma and saliva, and have been identified as disease markers for cancer and infectious diseases. To this end, we use as a model system an 88-mer target from the RV1910c gene in Mycobacterium tuberculosis, which is associated with antibiotic (isoniazid) resistance in TB. Upon binding to short probes attached to long carrier DNA, we show that resistive-pulse sensing in nanopipets is capable of identifying rather subtle structural differences, such as the hybridization state of the probes, in a statistically robust manner. With significant potential toward multiplexing and high-throughput analysis, our study points toward a new, single-molecule DNA-assay technology that is fast, easy to use, and compatible with point-of-care environments.

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BACKGROUND: In young patients with native aortic coarctation (CoA), the management of choice is surgery. However, in re-coarctation (re-CoA) surgery is associated with increased morbidity and even mortality. Some children with native CoA present relative contraindications for surgery. METHODS: From 2006 to 2017, thirty-four patients (male n = 20; 59%) from two centres with re-CoA (31) and native CoA (3) were managed by stent implantation with premounted balloon expandable stents. Inclusion criteria were age < 3 years and >1 month, weight < 16 kg. Median age was 6,5 months (min. 1; max. 34 months), median weight 6,2 kg (min. 3,7; max. 16 kg). Thirteen patients (38%) had Re-CoA and hypoplastic left heart syndrome (HLHS). In three patients (9%) the native CoA was stented due to contraindications for surgical treatment. RESULTS: All procedures were successful. The median peak invasive systolic pressure gradient declined from 31 mm Hg (max. 118; min. 4) to 0 mm Hg (max. 32; min.-7) (p < 0.001). The median minimal diameter of the narrowed segment of aorta increased from 3 mm (max. 6,9; min. 1,0) to 7 mm (max. 11,5; min. 3,5) (p < 0.001). There were no serious complications. The median follow-up time was 12,5 months (max. 88; min. 0 month). During this time ten patients (29%) required re-dilatation and two of them re-stenting. CONCLUSION: Percutaneous stent implantation for Re-CoA and in selected patients for native CoA can be performed successfully in very young patients with a good immediate hemodynamical result. However, repeated stent angioplasties and further on interventional 'opening' of the stent is necessary to augment the aorta to adult size.

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Especially complicated, renal lithiasis contributes to the general inflammatory syndrome development that interferes with nonspecific, humoral and cellular immune system. The surgical treatment of nephrolithiasis is closely related to drug therapy of urinary infection, one of the reasons being the reduction of the immune status. The work is performed by evaluating the immunological status preoperatively in 58 patients with complicated lithiasis. The analysis of the status in these patients demonstrated that complicated urolithiasis results in significant changes in the immune system, these changes being expressed at the cellular and humoral level of immunity.

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Clostridial neurotoxins have assumed increasing importance in clinical application. The toxin's light chain component (LC) inhibits synaptic transmission by digesting vesicle-docking proteins without directly altering neuronal health. To study the properties of LC gene expression in the nervous system, an adenoviral vector containing the LC of tetanus toxin (AdLC) was constructed. LC expressed in differentiated neuronal PC12 cells was shown to induce time- and concentration-dependent digestion of mouse brain synaptobrevin in vitro as compared to control transgene products. LC gene expression in the rat lumbar spinal cord disrupted hindlimb sensorimotor function in comparison to control vectors as measured by the Basso-Beattie-Bresnahan (BBB) scale (P<0.001) and rotarod assay (P<0.003). Evoked electromyography (EMG) showed increased stimulus threshold and decreased response current amplitude in LC gene-transferred rats. At the peak of functional impairment, neither neuronal TUNEL staining nor reduced motor neuron density could be detected. Spontaneous functional recovery was observed to parallel the cessation of LC gene expression. These results suggest that light chain gene delivery within the nervous system may provide a nondestructive means for focused neural inhibition to treat a variety of disorders related to excessive synaptic activity, and prove useful for the study of neural circuitry.

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STUDY OBJECTIVES: Opioids delivered to the pons inhibit REM sleep, whereas pontine administration of adenosine enhances REM sleep. In other brain areas opioids and adenosine interact to produce antinociception. Adenosine A1 receptors and mu opioid receptors each activate Gi/Go proteins. This study tested the hypothesis that combined treatment with the adenosine A1 receptor agonist SPA and the mu opioid agonist DAMGO would enhance G protein activation to a greater level than produced by either agonist alone. G protein activation was quantified in seven brainstem regions regulating sleep and nociception. This study also tested the hypothesis that G protein activation caused by SPA would be concentration dependent and blocked by the adenosine A1 receptor antagonist DPCPX. DESIGN: Activation of G proteins was assessed autoradiographically by agonist stimulation of [35S]GTPgammaS binding in slide-mounted sections of rat brainstem. G protein activation was quantified in nCi/g tissue for pontine reticular formation, dorsal raphe, ventrolateral and dorsomedial periaqueductal gray, and laterodorsal and pedunculopontine tegmental nuclei. SETTING: N/A. PATIENTS OR PARTICIPANTS: N/A. MEASUREMENTS AND RESULTS: Combined treatment with SPA and DAMGO caused a partially additive increase in G protein activation that was significantly (p<0.01) greater than G protein activation caused by either agonist alone. Treatment with SPA alone caused a concentration dependent (p<0.001) increase in [35S]GTPgammaS binding that was blocked by DPCPX. CONCLUSION: Agonist activation of adenosine A1 receptors stimulates G proteins in brainstem nuclei regulating sleep and nociception. In these same nuclei, G protein activation by combined treatment with DAMGO and SPA was partially additive, suggesting that mu opioid and adenosine A1 receptors activate some common G protein pools.

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Rats decrease intake of a saccharin conditioned stimulus (CS) when followed by: (1) the administration of an aversive agent such as lithium chloride (referred to as a conditioned taste aversion, CTA); (2) access to a very palatable concentration of sucrose (referred to as an anticipatory contrast effect, ACE); or (3) the administration of a drug of abuse. It is not clear, however, whether the suppressive effects of drugs of abuse are mediated by their aversive or rewarding properties. The present set of experiments addressed this issue by examining the suppressive effects of morphine in rats with a lesion thought to dissociate the two phenomena (i.e., CTA and ACE). The results show that bilateral ibotenic acid lesions of the gustatory thalamus eliminate the suppressive effects of morphine, but fail to disrupt the suppressive effects of the aversive agent, lithium chloride. This pattern of results argues against the CTA account in favor of the reward comparison hypothesis. Specifically, the data suggest that rats suppress intake of a saccharin CS in anticipation of the availability of a preferred drug of abuse and that the gustatory thalamus is essential for this type of reward comparison process.

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Intake of a saccharin-conditioned stimulus (CS) can be suppressed following pairing with an aversive agent such as lithium chloride (LiCl) or x-rays (referred to as a conditioned taste aversion or CTA), a highly rewarding sucrose solution (referred to as an anticipatory contrast effect), or a drug of abuse such as morphine or cocaine. Although the suppressive effects of LiCl and sucrose are clear examples of aversive and appetitive conditioning, respectively, it is not certain which properties (aversive or appetitive) mediate the suppressive effects of drugs of abuse. It is known, however, that the suppressive effects of a rewarding sucrose US are attenuated when using a caloric sucrose CS in food deprived rats, while LiCl induced CTAs are much less effected. Standard CTA testing typically is conducted in water-deprived rather than food-deprived rats and, although LiCl is known to suppress intake of a sucrose CS in water-deprived rats, the suppressive effects of drugs of abuse have not been evaluated under these conditions. The present experiment, then, compared the suppressive effects of a standard dose of morphine (15 mg/kg) and a matched dose of LiCl (0.009 M) on intake of a sucrose CS in water-deprived and free-feeding rats. The results showed that both drugs suppressed intake in free-feeding subjects, but only the aversive agent, LiCl, reduced CS intake in the water-deprived rats. This finding dissociates the suppressive effects of morphine and LiCl and, in so doing, aligns the suppressive effects of morphine with those of an appetitive sucrose US.

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The early pathophysiology of diabetic retinopathy and the involvement of neural and vascular malfunction are poorly understood. Glial cells provide structural and metabolic support for retinal neurons and blood vessels, and the cells become reactive in certain injury states. We therefore used the streptozotocin rat model of short-term diabetic retinopathy to study glial reactivity and other glial functions in the retina in the first months after onset of diabetes. With a two-site enzyme-linked immunosorbent assay, we measured the expression of the intermediate filament glial fibrillary acidic protein (GFAP). After 1 month, GFAP was largely unchanged, but within 3 months of the beginning of diabetes, it was markedly induced, by fivefold (P < 0.04). Immunohistochemical staining showed that the GFAP induction occurred both in astrocytes and in Müller cells. Consistent with a glial cell malfunction, the ability of retinas to convert glutamate into glutamine, assayed chromatographically with an isotopic method, was reduced in diabetic rats to 65% of controls (P < 0.01). Furthermore, retinal glutamate, as determined by luminometry, increased by 1.6-fold (P < 0.04) after 3 months of diabetes. Taken together, these findings indicate that glial reactivity and altered glial glutamate metabolism are early pathogenic events that may lead to elevated retinal glutamate during diabetes. These data are the first demonstration of a specific defect in glial cell metabolism in the retina during diabetes. These findings suggest a novel understanding of the mechanism of neural degeneration in the retina during diabetes, involving early and possibly persistent glutamate excitotoxicity.

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Rare heterogeneous syndrome, the prune belly syndrome was first described in 1839 and associates the agenesis of the abdominal musculature with other complex malformations of the genitourinary tract and bilateral cryptorchidism. In this plurimalformative context, the main evolutive problem is represented by the chronic renal insufficiency. The work presents a new case of prune belly syndrome which through its clinical evolutive aspects joins the category of classical cases published in literature.

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The paper reports on a case of chronic pyelonephritis with bacillus Proteus, generated by an intravesical foreign body (sewing needle). The needle was extracted with surgical cystoscope. After removing the foreign body, nalidixic acid was administered. The immediate evolution of the case was good.

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The paper reports on three cases of congenital lobular emphysema with warning respiratory manifestations as early as infancy. Starting from the clinical picture of respiratory distress, the diagnosis was established radiologically. The authors discuss the etiopathogenic aspects of the disease and its clinical-radiological manifestations, with the decisive role of the radiological exploration in diagnosis. The extension of respiratory dysfunction and the possible complications determine the opportunity of surgery.

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The paper reports on the etiopathogenetic aspects of mediastinitis, clinical and radiological semeiology, the latter with a decisive role in establishing the diagnosis. The priority character of therapy is emphasized. Three cases of mediastinitis in children are presented: a mediastinal abscess, a suppurated mediastinitis with favourable evolution after drainage and a mediastinitis secondary to a fistula on a postcaustic stenosed esophagus.

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The paper reports on two cases of pneumomediastinum in the newborn child: a benign form with clinical picture and radiological scan of subcutaneous cervical emphysema; and a severe form of pneumocystosis complicated with suffocating pneumomediastinum and pneumothorax. The authors discuss the etiopathogenic aspects of pneumomediastinum in the newborn, the clinical and radiological semeiologies, the latter being of a high diagnosis importance. The therapeutic modalities are indicated in terms of the extent to which breathing is affected.

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Leukocyte migration inhibitory factor (LMIF) activity was tested before and after glucagon administration both in vivo and in vitro. In vivo glucagon 1 mg i.v. vs saline administration inhibited LMIF production by T lymphocytes in 85.21% patients (p less than 0.01). In vitro glucagon in physiologic (125 pg/ml) and pharmacologic (50 ng/ml) doses increased the migration area vs PPD 250 microL (migration index 0.5127 vs 0.3210; p less than 0.05). These results show a significant inhibitory effect of glucagon upon LMIF activity. We suggest that glucagon acts by enhancement of the intralymphocytic cAMP/cGMP ratio (cyclic adenosine monophosphate/cyclic guanosine monophosphate).

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Spirographic investigations were carried out in a lot of 125 children and adolescents with surgical exeresis or collapse, performed between 1965 and 1972 for suppurations, tuberculosis and other thoraco-pulmonary diseases. Spirographic determinations before and 1--2 months after surgery showed that the postoperative sequelae were milder in children than in adults. Recovery of the ventilation function was more complete than that of the pulmonary circulation. The necessity of a correct postoperative care and systematic, prolonged respiratory kinesitherapy is emphasized.

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