Starting A Peripheral Nerve Surgery Unit in an Area of Limited Resources - Our Experience

Dedicated peripheral nerve surgery centers are few in developing countries where majority of affected patients either remain untreated or are simply palliated with just physiotherapy. In this chapter, we review our experience with surgery for peripheral nerve lesions and peripheral nerve injuries over a 5-year period. A total of 68 procedures were carried out for 58 patients with various peripheral nerve lesions and injuries. Among the 19 surgeries for adult brachial plexus injuries, 10 were for pan-brachial plexus injury, 2 procedures for lower brachial plexus injuries, and 7 procedures for upper brachial plexus injury, while 11 repair surgeries were done for pediatric brachial plexus injuries. The remaining 38 surgeries included 21 peripheral nerve sheath tumor excisions, 5 ablative procedures for chronic neuralgia, 8 procedures for non-carpal tunnel peripheral nerve entrapments, and 4 adults with upper or lower limb isolated nerve injury repairs. The patients were followed up between 6 months and 2 years post-surgery for functional outcome assessment. Overall, as many as 57.5% of the patients had significant neurologic improvement noticed at 2 years of follow-up. Despite its challenges, optimal outcomes following surgery are still possible for patients with nerve injuries, entrapments, and nerve tumors in developing countrie

Electron induced nanoscale nuclear spin relaxation probed by hyperpolarization injection

We report on experiments that quantify the role of a central electronic spin as a relaxation source for nuclear spins in its nanoscale environment. Our strategy exploits hyperpolarization injection from the electron as a means to controllably probe an increasing number of nuclear spins in the bath, and subsequently interrogate them with high fidelity. Our experiments are focused on a model system of a nitrogen vacancy (NV) center electronic spin surrounded by several hundred 13C nuclear spins. We observe that the 13C transverse spin relaxation times vary significantly with the extent of hyperpolarization injection, allowing the ability to measure the influence of electron mediated relaxation extending over several nanometers. These results suggest interesting new means to spatially discriminate nuclear spins in a nanoscale environment, and have direct relevance to dynamic nuclear polarization and quantum sensors and memories constructed from hyperpolarized nuclei.Comment: 5 pages, 4 figures. SI: 1 page, 2 figures. 3 anc movie files (also available on Youtube

Non-descent vaginal hysterectomy in women with previous caesarean section scar: our experience

Background: Hysterectomy is one of the common gynaecological major surgeries performed worldwide. In spite of technological advancement with laparoscopic and robotic hysterectomy conventional hysterectomy through vaginal route of nonprolapse uterus popularly known as, Non-Descent Vaginal Hysterectomy (NDVH) remains a justifiable cost effective, cosmetically appealing option especially in resource-crunched developing country. NDVH in post caesarean scarred uterus too a technically challenged procedure requiring skills and expertise.Assessment of technical feasibility and safety of non-descent vaginal hysterectomy in women with previous caesarean section scar were studied.Methods: The study was a prospective observational study of 72 patients with LSCS scar requiring hysterectomy for benign conditions were selected based on the inclusion and exclusion criteria carried out from June 2012 to May 2017. Operating time, blood loss, surgical techniques, intra/postoperative challenges, conversion to laparotomy or laparoscopic assistance and length of hospital stay were recorded for each case. Patients were followed up till 03 months of surgery.Results: Vaginal hysterectomy was successful in all cases. Morcellation, bisection or myomectomy, were done in 86% cases. Two patients had bladder injury, which was repaired vaginally, two cases required support of laparoscopy.  No patients needed blood transfusion. None of the patients were converted to laparotomy.Conclusions: Vaginal hysterectomy is a safe and effective procedure for benign non-prolapsed uteri in women with previous caesarean section scar when uterine size is less than 14 weeks. Standby operating laparoscopy provides added advantages to surgeon in doubtful or difficult cases to avoid conversion laparotomy

MEROPENEM INDUCED REDUCTION IN SERUM VALPROATE LEVEL- A CASE REPORT

Objective: To report a case of meropenem induced reduction in serum valproate level. Methods: The clinical data of an epileptic patient who experienced a decrease in seizure control due to a drug interaction between valproate and meropenem is described.Results: The patient was a 26 years old male who was a known case of refractory focal epilepsy and underwent surgery for the same. This patient was on five antiepileptic drugs including valproate. On treatment with meropenem for the management of post surgical site infection due to multidrug resistant Klebsiella pneumoniae, the patient experienced seizures due to decline in valproate level. Increasing the dose of valproate could not control the seizures. However, changing the antibiotics to a non carbapenem controlled the seizures.Conclusion: The present report highlights the potential drug interaction between valproate and meropenem. Physicians should thus avoid co-administration of both these agents. If concomitant administration is essential, close monitoring of valproate concentration and clinical monitoring for breakthrough seizures are necessitated.Â

Floquet prethermalization with lifetime exceeding 90s in a bulk hyperpolarized solid

We report the observation of long-lived Floquet prethermal states in a bulk solid composed of dipolar-coupled $^{13}$C nuclei in diamond at room temperature. For precessing nuclear spins prepared in an initial transverse state, we demonstrate pulsed spin-lock Floquet control that prevents their decay over multiple-minute long periods. We observe Floquet prethermal lifetimes $T_2'\approx$90.9s, extended >60,000-fold over the nuclear free induction decay times. The spins themselves are continuously interrogated for $\sim$10min, corresponding to the application of $\approx$5.8M control pulses. The $^{13}$C nuclei are optically hyperpolarized by lattice Nitrogen Vacancy (NV) centers; the combination of hyperpolarization and continuous spin readout yields significant signal-to-noise in the measurements. This allows probing the Floquet thermalization dynamics with unprecedented clarity. We identify four characteristic regimes of the thermalization process, discerning short-time transient processes leading to the prethermal plateau, and long-time system heating towards infinite temperature. This work points to new opportunities possible via Floquet control in networks of dilute, randomly distributed, low-sensitivity nuclei. In particular, the combination of minutes-long prethermal lifetimes and continuous spin interrogation opens avenues for quantum sensors constructed from hyperpolarized Floquet prethermal nuclei.Comment: 5 pages, 5 figures. SI: 2 pages, 4 figure

Temporal fossa arachnoid cyst presenting with bilateral subdural hematoma following trauma: two case reports

<p>Abstract</p> <p>Introduction</p> <p>Intracranial arachnoid cysts are considered to be congenital malformations with a predilection for the temporal fossa. They are often asymptomatic but can sometimes be symptomatic due to enlargement or hemorrhage. There are multiple case reports of arachnoid cysts becoming symptomatic with hemorrhagic complications following head trauma. In such cases, the bleeding is often confined to the side ipsilateral to the arachnoid cyst. Occurrence of contralateral subdural hematomas in patients with temporal fossa arachnoid cysts has rarely been observed and is reported less frequently in the medical literature.</p> <p>Case presentation</p> <p>We report two cases of people (a 23-year-old man and a 41-year-old man) with temporal fossa arachnoid cysts complicated by a subdural hematoma following head injury. Both patients developed a subdural hematoma contralateral to the side of a temporal fossa arachnoid cyst. It is likely that lack of adequate intracranial cushioning in the presence of an intracranial arachnoid cyst may result in injury not only to ipsilateral but also to contralateral bridging veins, following head trauma.</p> <p>Conclusion</p> <p>It is important to identify and report such rare complications with intracranial arachnoid cysts, so that asymptomatic patients with an intracranial arachnoid cyst can be counseled about such possibilities following head trauma.</p

Effective permittivity of random plasmonic composites

An effective-medium theory (EMT) is developed to predict the effective permittivity \epsilon_eff of dense random dispersions of high optical-conductivity metals such as Ag, Au and Cu. Dependence of \epsilon_eff on the volume fraction \phi, a microstructure parameter \kappa related to the static structure factor and particle radius a is studied. In the electrostatic limit, the upper and lower bounds of \kappa correspond to Maxwell-Garnett and Bruggeman EMTs respectively. Finite size effects are significant when |\beta^2(ka/n)^3| becomes O(1) where \beta, k, and n denote the nanoparticle polarizability, wavenumber and matrix refractive index respectively. The coupling between the particle and effective medium results in a red-shift in the resonance peak, a non-linear dependence of \epsilon_eff on \phi, and Fano resonance in \epsilon_eff.Comment: Manuscript submitted to J. Opt. Soc. Am. B. 33 page

Phase I Study of the Safety and Pharmacokinetics of Plerixafor in Children Undergoing a Second Allogeneic Hematopoietic Stem Cell Transplantation for Relapsed or Refractory Leukemia

AbstractThe safety, pharmacokinetics, and biological effect of plerixafor in children as part of a conditioning regimen for chemo-sensitization in allogeneic hematopoietic stem cell transplantation (HSCT) have not been studied. This is a phase I study of plerixafor designed to evaluate its tolerability at dose of .24 mg/kg given intravenously on day −4 (level 1); day −4 and day −3 (level 2); or day −4, day −3, and day −2 (level 3) in combination with fludarabine, thiotepa, melphalan, and rabbit antithymocytic globulin for a second allogeneic HSCT in children with refractory or relapsed leukemia. Immunophenotype analysis was performed on blood and bone marrow before and after plerixafor administration. Twelve patients were enrolled. Plerixafor at all 3 levels was well tolerated without dose-limiting toxicity. Transient gastrointestinal side effects of National Cancer Institute–grade 1 or 2 in severity were the most common adverse events. The area under the concentration-time curve increased proportionally to the dose level. Plerixafor clearance was higher in males and increased linearly with body weight and glomerular filtration rate. The clearance decreased and the elimination half-life increased significantly from dose level 1 to 3 (P < .001). Biologically, the proportion of CXCR4+ blasts and lymphocytes both in the bone marrow and peripheral blood increased after plerixafor administration

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe