Selective vulnerability of the ventral hippocampus-prelimbic cortex axis parvalbumin interneuron network underlies learning deficits of fragile X mice

High-penetrance mutations affecting mental health can involve genes ubiquitously expressed in the brain. Whether the specific patterns of dysfunctions result from ubiquitous circuit deficits or might reflect selective vulnerabilities of targetable subnetworks has remained unclear. Here, we determine how loss of ubiquitously expressed fragile X mental retardation protein (FMRP), the cause of fragile X syndrome, affects brain networks in Fmr1y/- mice. We find that in wild-type mice, area-specific knockout of FMRP in the adult mimics behavioral consequences of area-specific silencing. By contrast, the functional axis linking the ventral hippocampus (vH) to the prelimbic cortex (PreL) is selectively affected in constitutive Fmr1y/- mice. A chronic alteration in late-born parvalbumin interneuron networks across the vH-PreL axis rescued by VIP signaling specifically accounts for deficits in vH-PreL theta-band network coherence, ensemble assembly, and learning functions of Fmr1y/- mice. Therefore, vH-PreL axis function exhibits a selective vulnerability to loss of FMRP in the vH or PreL, leading to learning and memory dysfunctions in fragile X mice.

The effect of botulinum toxin A in unilateral cleft lip scar: comparison of results with different sites of injection

Botulinum toxin type A (BTA) injections into the subjacent orbicularis oris muscle have been shown to improve appearance and produce narrower cheiloplasty scars. This study was performed to determine the effect of BTA injected at different sites on the unilateral cleft lip scar and cleft side nostril width. A double-blind, randomized prospective trial was conducted involving 64 consecutive patients with unilateral cleft lip undergoing primary cheiloplasty between September 2016 and January 2019. The patients were randomized to receive BTA injections either into the subjacent orbicularis oris muscle (4 points group) or into the bilateral nasolabial fold region (6 points group) during cheiloplasty. The scars were assessed by photographic scar width measurements and Vancouver scar scale assessment tool. The cleft side nostril width was compared to the non-cleft side width. Fifty-six patients completed the trial, 24 in the 4 points group and 31 in the 6 points group. There was no significant difference in scar width or nostril width measurements between the groups at the end of follow-up. The Vancouver scar scale assessment was also similar between the groups. There was no significant difference in scar width or nostril width measurements after cleft lip repair between patients treated with botulinum toxin injections to the subjacent orbicularis oris muscle and patients treated with injections in the nasolabial region.

Parvalbumin Interneuron Plasticity for Consolidation of Reinforced Learning

Parvalbumin (PV) basket cells are widespread local interneurons that inhibit principal neurons and each other through perisomatic boutons. They enhance network function and regulate local ensemble activities, particularly in the γ range. Organized network activity is critically important for long-term memory consolidation during a late time window 11-15 h after acquisition. Here, we discuss the role of learning-related plasticity in PV neurons for long-term memory consolidation. The plasticity can lead to enhanced (high-PV) or reduced (low-PV) expression of PV/GAD67. High-PV plasticity is induced upon definite reinforced learning in early-born PV basket cells, whereas low-PV plasticity is induced upon provisional reinforced learning in late-born PV basket cells. The plasticity is first detectable 6 h after acquisition, at the end of a time window for memory specification through experience, and is critically important 11-15 h after acquisition for enhanced network activity and long-term memory consolidation. High- and low-PV plasticity appear to regulate activity in distinct local networks of principal neurons and PV basket cells. These findings suggest how flexibility and stability in learning and memory might be implemented through parallel circuits and networks.

Non-response to first-line anti-tuberculosis treatment in Sikkim, India: a risk-factor analysis study

Setting: Sikkim, India, has the highest proportion of tuberculosis (TB) patients on first-line anti-tuberculosis regimens with the outcome 'failure' or 'shifted to regimen for multidrug-resistant TB (MDR-TB)'. Objective: To assess the factors associated with non-response to treatment, i.e., 'failure' or 'shifted to MDR-TB regimen'. Methods: We conducted a retrospective cohort study using Revised National Tuberculosis Control Programme data of all TB patients registered in 2015 for first-line TB treatment. In addition, we interviewed 42 patients who had not responded to treatment to ascertain their current status. Results: Of 1508 patients enrolled for treatment, about 9% were classified as non-response to treatment. Patient factors associated with non-response were urban setting (adjusted odds ratio [aOR] 2.39, 95%CI 1.22-4.67), ethnicity (being an Indian tribal, aOR 1.73, 95%CI 1.17-2.57, Indian [other] aOR 1.83, 95%CI 1.29-2.60 compared to patients of Nepali origin) and those on retreatment (aOR 2.40, 95%CI 1.99-2.91). Of the patients interviewed, 28 (67%) had received treatment for drug-resistant TB. Conclusion: In Sikkim, one in 11 patients had not responded to first-line anti-tuberculosis treatment. Host-pathogen genetics and socio-behavioural studies may be required to understand the reasons for the differences in non-response, particularly among ethnic groups.

Surgical safety distances in the infratemporal fossa: three-dimensional measurement study

The wedge-shaped infratemporal fossa is a constricted space and has long been a surgical challenge, mainly due to difficulties in access. Three-dimensional (3D) reconstruction of the skull, internal carotid artery (ICA), and internal jugular vein (IJV) was carried out using enhanced computed tomography (CT) data, to measure the safety distances in relation to infratemporal fossa surgery. Fifty enhanced CT datasets were selected to reconstruct 3D images by segmentation technique. The anatomical routes of the ICA, IJV, and the styloid process (SP) were observed. The following were measured: SP length, height of the pterygoid plates (PP height), distances from the pterygoid process (antero-inferior and anterosuperior border) to the leading edge of the ICA (PP-ICA (inferior), PP-ICA (superior)), and distance between the most prominent point of the zygomatic arch and the medial pterygoid plate (Zyg-MPP). The mean measurements of SP length, PP height, and the distances PP-ICA (inferior), PP-ICA (superior), and Zyg-MPP were 30.64 mm, 26.61 mm, 31.16 mm, 34.37 mm, and 51.37 mm, respectively. No significant differences were observed by age group, except the distance of PP-ICA (inferior) on the left side. In centres without intraoperative navigation facilities, proper knowledge of the anatomy, particularly of bony landmarks and the safe distances to nearby neurovascular structures, can provide useful information to ensure safe operations.

Distribution and skill mix of health workforce in Nepal

BACKGROUND

Distribution and skill mix of health workforce has always been a challenge in rural Nepal. Workforce surpluses or shortages and inappropriate skill mix, decrease productivity and efficiency, deplete scarce resources and squander worker capabilities. This study was aimed at generating evidences on the current distribution and skill mix of health workforce in Nepal.

METHODS

A cross-sectional study was conducted using both qualitative and quantitative methods.Fifteen districts representing three eco-developmental regions of Nepal were selected using multi-stage cluster sampling method. Out of 404 sampled health institutions, 747 health workers from 375 health institutions were interviewed. Observation was carried out in 256 health facilities.

RESULTS

Currently, the vacant positions are mostly of doctors 74(38%) technicians 28 (21%) nurses 50 (10%) and paramedics 26 (6%)with respect to sanctioned positions. Variations of fulfilled positions occurred in all three ecological belts, with the Hill belt having the highest proportion of vacant posts 116 (16%).On the basis of types of health facilities, ayurvedic centres have the highest fulfilled positions 55 (95%) and the lowest in primary healthcare centres (PHCCs) 162 (81%). Proper skill mix was observed in 6 (43%) of hospitals and 3(18%) of PHCCs.Only 132 (17.7%) of health workers have taken part in orientation on non-communicable diseases (NCDs) despite the increasing trend of NCDs.

CONCLUSIONS

There is scarcity of health workforce with appropriate skills, particularly in rural Nepal. Sanctioned positions and categories of health workers need to be revised on the basis of population growth and epidemiological shifts.

Synthesis, molecular modeling, and pharmacological testing of bis-quinolinium cyclophanes: potent, non-peptidic blockers of the apamin-sensitive Ca(2+)-activated K(+) channel

The synthesis and pharmacological testing of two series of novel bis-quinolinium cyclophanes as blockers of the apamin-sensitive Ca(2+)-activated K(+) (SK(Ca)) channel are presented. In these cyclophanes the two 4-aminoquinolinium groups are joined at the ring N atoms (linker L) and at the exocyclic N atoms (linker A). In those cases where A and L contain two or more aromatic rings each, the activity of the compound is not critically dependent upon the nature of the linkers. When A and L each have only one benzene ring, the blocking potency changes dramatically with simple structural variations in the linkers. One of these smaller cyclophanes having A = benzene-1,4-diylbis(methylene) and L = benzene-1, 3-diylbis(methylene) (3j, 6,10-diaza-1,5(1,4)-diquinolina-3(1,3),8(1, 4)-dibenzenacyclodecaphanedium tritrifluoroacetate, UCL 1684) has an IC(50) of 3 nM and is the most potent non-peptidic SK(Ca) channel blocker described to date. Conformational analysis on the smaller cyclophanes using molecular modeling techniques suggests that the differences in the blocking potencies of the compounds may be attributable to their different conformational preferences.

Intravenous streptokinase in the management of a subset of patients with unstable angina: a randomized controlled trial

We report the results of a randomized controlled trial of intravenous streptokinase in a subset of patients with unstable angina. Seventy-six patients were admitted with prolonged (more than 20 minutes) angina at rest of less than 3 weeks onset. Fifty-two patients continued to have more than 3 episodes of prolonged angina in 48 hours on medical therapy with metoprolol, isosorbide dinitrate, nifedipine and intravenous nitroglycerin. Forty-eight patients consented to enter the study and were randomized into two groups. The first group, of 24 patients, received 1.5 million units of streptokinase infusion and the second group, also of 24 patients, received a placebo. Pain relief within 48 hours was achieved in 19/24 (79.1%) patients after streptokinase infusion as compared to 9/24 (37.5%) of the controls (P less than 0.05). Approximately 90% (17/19) of patients responding to streptokinase therapy were relieved of chest pain within the first six hours as against none in the controls. The incidence of acute myocardial infarction within six months was 12.5% (3/24) in those receiving streptokinase and 25% (6/24) in the controls. Mortality at six months stood at 8.33% (2/24) in the treated patients and 16.6% (4/24) in the controls. Intravenous streptokinase thus appears to be of benefit in patients with angina at rest of recent onset which does not respond to conventional medical therapy.

Failure of oral atenolol and verapamil to increase the capacity and duration of exercise in patients in sinus rhythm with mitral stenosis

The efficacy of oral atenolol in increasing the capacity and duration of exercise in 43 patients in sinus rhythm with mitral stenosis was evaluated and compared with that of oral verapamil in an open-label cross-over design. It was observed that although oral atenolol (100 mg per day) caused significant reductions in heart rate while resting and during exercise (P less than 0.001), the increases in capacity and duration of exercise were not significant. Oral verapamil (80 mg three times per day) also caused significant reductions in the heart rates at rest and during exercise (P less than 0.05) but the increases observed, although greater than that with atenolol, failed to reach the level of statistical significance. Occasional side effects occurred with both the drugs. Subjective symptoms of dyspnoea at rest and on exertion were relieved with both the drugs. We conclude that, although both drugs reduce the symptoms of dyspnoea, they cause only minor increases in the objective parameters. They do not, therefore, provide an alternative to surgery and have only a temporary place in the management of patients in sinus rhythm with mitral stenosis who are awaiting surgery.

Development of subaortic stenosis and regurgitation several years after successful operation on a common atrium

A patient who had had successful operation for a common atrium subsequently developed subaortic stenosis and regurgitation several years later. The diagnosis of subaortic lesion was confirmed by echocardiography. This case shows that the left ventricular outflow tract gradient should be measured before operation for common atrium and that after operation such cases should be examined by cross sectional echocardiography at follow up visits.

Sinus arrest caused by atenolol-verapamil combination

A case on concomitant atenolol-verapamil therapy for hypertension and angina pectoris, developing sinus arrest and life-threatening bradycardia is described. The complication occurred with low doses of both the agents and normal electrophysiologic status of the heart. The example suggests that pharmacodynamic synergism contributes more than pharmacokinetic interaction causing adverse reactions during beta blocker-verapamil therapy.

Value of the treadmill exercise test in asymptomatic and minimally symptomatic patients with chronic severe aortic regurgitation

The value of the graded treadmill exercise test was assessed in 19 asymptomatic and minimally symptomatic (13 NYHA class I and 6 NYHA class II) male patients with chronic severe aortic regurgitation. It was observed that, in 2 patients who showed significant ST segment depression at peak exercise, the total exercise duration was significantly shorter (P less than 0.001) than in the patients not showing such changes. During left ventricular and aortic root angiography (in both patients) and selective left coronary angiography (in one of them), ST segment changes similar to those seen during exercise testing were observed. The mean rise in left ventricular end-diastolic pressure after injection of contrast material was significantly more (P less than 0.001) in these 2 patients compared to the other 17 patients. Both patients had normal resting M-mode echocardiographic parameters. It is concluded that ST segment depression on exercise testing and reduced exercise capacity are indicants of exercise-induced left ventricular dysfunction in asymptomatic and minimally symptomatic patients with chronic severe aortic regurgitation. Furthermore, it is suggested that this simple and cheap test can be used for serial evaluation of such patients in the absence of the facility of radionuclide cineangiography.