Nuclear export of the pre-60S ribosomal subunit through single nuclear pores observed in real time.

Ribosomal biogenesis has been studied by biochemical, genetic and electron microscopic approaches, but live cell data on the in vivo kinetics are still missing. Here we analyse the export kinetics of the large ribosomal subunit (pre-60S particle) through single NPCs in human cells. We established a stable cell line co-expressing Halo-tagged eIF6 and GFP-fused NTF2 to simultaneously label pre-60S particles and NPCs, respectively. By combining single molecule tracking and super resolution confocal microscopy we visualize the dynamics of single pre-60S particles during export through single NPCs. For export events, maximum particle accumulation is found in the centre of the pore, while unsuccessful export terminates within the nuclear basket. The export has a single rate limiting step and a duration of ∼24 milliseconds. Only about 1/3 of attempted export events are successful. Our results show that the mass flux through a single NPC can reach up to ~125 MDa·s-1 in vivo.

Crumbs2 Is an Essential Slit Diaphragm Protein of the Renal Filtration Barrier.

BACKGROUND: Crumbs2 is expressed at embryonic stages as well as in the retina, brain, and glomerular podocytes. Recent studies identified CRB2 mutations as a novel cause of steroid-resistant nephrotic syndrome (SRNS). METHODS: To study the function of Crb2 at the renal filtration barrier, mice lacking Crb2 exclusively in podocytes were generated. Gene expression and histologic studies as well as transmission and scanning electron microscopy were used to analyze these Crb2podKO knockout mice and their littermate controls. Furthermore, high-resolution expansion microscopy was used to investigate Crb2 distribution in murine glomeruli. For pull-down experiments, live cell imaging, and transcriptome analyses, cell lines were applied that inducibly express fluorescent protein-tagged CRB2 wild type and mutants. RESULTS: Crb2podKO mice developed proteinuria directly after birth that preceded a prominent development of disordered and effaced foot processes, upregulation of renal injury and inflammatory markers, and glomerulosclerosis. Pull-down assays revealed an interaction of CRB2 with Nephrin, mediated by their extracellular domains. Expansion microscopy showed that in mice glomeruli, Crb2 and Nephrin are organized in adjacent clusters. SRNS-associated CRB2 protein variants and a mutant that lacks a putative conserved O-glycosylation site were not transported to the cell surface. Instead, mutants accumulated in the ER, showed altered glycosylation pattern, and triggered an ER stress response. CONCLUSIONS: Crb2 is an essential component of the podocyte's slit diaphragm, interacting with Nephrin. Loss of slit diaphragm targeting and increasing ER stress are pivotal factors for onset and progression of CRB2-related SRNS.

Carbamazepine-induced hyponatremia - A wakeup call.

Carbamazepine-induced hyponatremia is a rare condition. The patients may or may not be symptomatic. Epilepsy is considered a social taboo. Hence, patients do not reveal history of being on antiepileptic agents. Carbamazepine is a known antiepileptic and psychotropic agent. It is commonly used for the treatment of seizures and psychiatric disorders. We present a case of a 60-year-old female patient presenting in emergency department with history of carbamazepine-induced hyponatremia. It raises antidiuretic hormone (ADH) levels. This leads to increased sensitivity of renal tubules to ADH levels. She was diagnosed as a case of syndrome of inappropriate ADH and was treated accordingly. She was asymptomatic and was ambulatory. She recovered significantly. Hence, it is essential to monitor sodium levels in patients on carbamazepine therapy and also on drugs with similar mechanism of action.

Epidural Volume Extension with Saline in Combined Spinal-Epidural Anesthesia for Hip Surgeries Using Low Dose of Intrathecal Hyperbaric Bupivacaine.

BACKGROUND AND AIMS: The aim of the study was to evaluate the effectiveness of epidural volume extension (EVE) technique in terms of sensory and motor block characteristics along with hemodynamic parameters as a part of combined spinal-epidural anesthesia (CSEA). MATERIALS AND METHODS: A total of 60 patients undergoing hip surgeries were assigned to one of the two groups containing 30 patients each. Group I (the CSE-EVE group) patients were anesthetized using CSE with EVE and Group II (the CSE group) patients were anesthetized using CSE without EVE, using the same technique and low dose of intrathecal hyperbaric bupivacaine. Sensory block characteristics were recorded using pinprick method, whereas motor blockade was assessed by modified Bromage scale. RESULTS: There was a statistically significant difference between the two groups regarding the level of maximum sensory block (P < 0.001), as Group I showed sensory block level extending to up to T4, whereas in Group II, it was limited to below T6. Time required for maximum sensory blockade was faster in Group I, ranging from 7 to 12 min (mean ± standard deviation [SD]: 9.83 ± 1.72), whereas in Group II, it ranged from 9 to 15 min (mean ± SD: 12.33 ± 1.83; P < 0.001). Two-segment regression was faster in Group II, ranging from 50 to 70 min (mean ± SD: 60.0 ± 6.30), whereas in Group I, it ranged from 80 to 105 min (mean ± SD: 89.67 ± 8.19; P < 0.001). The time required to reach the maximum motor block was faster in Group I, ranging from 2 to 4 min (mean ± SD: 2.67 ± 0.84), whereas in Group II, the time ranged from 2 to 6 min (mean ± SD: 3.50 ± 1.31; P < 0.001). CONCLUSION: CSEA with EVE is associated with early onset of sensory and motor blockade, high level of sensory block, and longer time of two-segment regression while maintaining hemodynamic stability due to decreased dose of intrathecal local anesthetic.

Lumbar epidural depth using transverse ultrasound scan and its correlation with loss of resistance technique: A prospective observational study in Indian population.

BACKGROUND AND OBJECTIVES: The objective of the present study was to evaluate the skin-epidural space distance as assessed by ultrasonography and conventional loss of resistance (LOR) technique and to find the correlation of epidural depth with body mass index (BMI). METHODS: Ninety-eight patients of either sex, American Society of Anesthesiology I/II, BMI <30 kg/m2 requiring lumbar epidural for surgery were enrolled. The epidural space was assessed with a curvilinear ultrasound (US) probe, 2-5 MHz, in the transverse plane at L3-L4 intervertebral space. Thereafter, the epidural depth from skin was assessed with conventional LOR method while performing the epidural. The needle depth (ND) was measured using a sterile linear scale, and any change in the needle direction or intervertebral space was noted. RESULTS: The patients were demographically similar. Depth of epidural space measured by US depth (UD) was 3.96 ± 0.44 cm (range 3.18-5.44 cm) and by ND was 4.04 ± 0.52 cm (range 2.7-5.7 cm). The Pearson's correlation coefficient (r) between UD and ND was 0.935 (95% confidence interval: 0.72-0.92, r2 = 0.874, P < 0.001), and Bland-Altman analysis revealed the 95% limits of agreement -0.494-0.652 cm. CONCLUSION: The present study demonstrates a good correlation between UD and ND and shows that the preprocedural US scan in transverse plane provides accurate needle entry site with a high success rate in single attempt for lumbar epidurals in patients with a BMI <30 kg/m2.

Malarial hepatopathy: a 6-year retrospective observational study from Uttarakhand, North India.

Background: Jaundice in malaria is multifactorial. Plasmodium falciparum causes malarial hepatopathy in around 2.5% of cases. The spectrum of hepatic dysfunction in patients with malaria varies from mild clinical and biochemical abnormalities to fulminant hepatic failure, although hepatic encephalopathy almost never occurs. We undertook this study in order to estimate the magnitude of hepatopathy in malaria, and study the associated clinical features, complications and outcome of patients. Methods: We retrospectively analyzed the data of patients with acute malaria hospitalized from between 2009 and 2015. We compared the clinical features, demographic parameters, laboratory findings, complications and outcome of patients with and without hepatopathy. Results: Hepatopathy was observed in 22% (215/978) (n=215) of those with acute malaria (n=978) due to mono-infection by Plasmodium vivax (56.7%) or P. falciparum (38.1%) and their co-infection (5.1%). The age of the patients ranged from 2 to 96 years, with male preponderance (63.2%). Bleeding events, thrombocytopenia, total leukocyte count, levels of transaminases (aspartate transaminases, alanine transaminases), serum bilirubin, serum albumin and serum creatinine, duration of hospitalization and mortality were significantly greater in patients with malarial hepatopathy (p<0.05). Also, hepatopathy and renal dysfunction were significantly associated (OR 5.35; p<0.001). Conclusion: Hepatopathy is a serious complication of malaria, and is associated with other organ dysfunction and greater mortality.

Efficacy of Platelet Rich Plasma via Lumbar Epidural Route in Chronic Prolapsed Intervertebral Disc Patients-A Pilot Study.

INTRODUCTION: Lumbar radiculopathy is a major health problem often treated by surgery or guided lumbar epidural steroids for pain relief. We have used Platelet Rich Plasma (PRP) a novel therapeutic tool of autologous nature that has emerged strongly in recent years to treat patients of prolapsed intervertebral disc. AIM: To evaluate the efficacy of PRP via interlaminar epidural route in treatment of pain in patients with prolapsed inter vertebral disc. MATERIALS AND METHODS: Ten patients were injected with five ml of autologous platelet rich plasma under fluoroscopic guidance via interlaminar lumbar epidural injection into area of affected nerve root. They were followed using VAS (Visual Analogue Scale), SLRT (Straight Leg Raising Test) and MODQ (Modified Oswestry Disability Questionnaire) for clinical improvement. RESULTS: Patients who had received epidural injections of autologous PRP showed improvements in their scores of evaluation tools. Improvement was sustained during the 3 month study period and was not associated with any complications. CONCLUSION: Autologous PRP can be considered as a good alternative to epidural steroids and surgery in management of patients with chronic prolapsed intervertebral disc.

Anaesthetic Management of Caesarean Section in a Term Pregnancy with Ventricular Septal Defect and Pulmonary Hypertension with Severe Pulmonary Stenosis.

Pregnancy with pulmonary hypertension - WHO risk class IV cardiac disease is associated with significant haemodynamic burden due to cardiocirculatory changes which is a significant indirect cause of maternal mortality. We report a very rare case - primigravida term pregnancy with pulmonary hypertension, large ventricular septal defect (2.4 cm(2)), bidirectional shunt mainly left to right with severe pulmonary stenosis with peak gradient of 144mmHg. Caesarean section was done under general anaesthesia with successful maternal and neonatal outcome.

Herpes Simplex Encephalitis: An Uncommon Presentation.

Herpes Simplex Virus (HSV) encephalitis is an uncommon illness, with about 2 cases per 250,000 per year. Most are caused by HSV-1, with 10% having HSV-2 as the aetiologic factor. We present a case of Herpes simplex type1encephalitis in a 70 year old male with an uncommon presentation. The patient was a known case of endogenous depression with no medical records and on no treatment for the same, reported with acute changes in mental state for the past five days. He was talking irrelevantly, had hallucinations and was unduly aggressive and violent. He was subjected to a thorough clinical and diagnostic work-up which included cerebrospinal fluid analysis, CT head and MRI brain. MRI brain was suggestive of mild subdural effusion which hinted towards infectious cause of encephalitis. The cerebrospinal fluid viral serology panel detected herpes simplex type 1 virus (HSV1) that was later confirmed by CSF Polymerase Chain Reaction (PCR) technique. Hence, acyclovir was initiated by intravenous route at a dosage of 10mg/kg body weight and continued for two weeks. This case holds significance in view of the fact that organic causes must be excluded in suspected cases of psychiatric illness especially in the absence of fever. Also, CSF-PCR testing plays a pivotal role in diagnosing herpes simplex encephalitis.

A Fatal Case of Acute Myeloid Leukaemia-Methotrexate Related or Primary Autoimmune Disease Related: A Rare Case Report.

Methotrexate is being used for many years in the treatment of chronic medical disorders e.g. rheumatoid arthritis since 1951. It has been associated with various systemic toxicities and complications including bone marrow suppression and lymphomas. The development of leukaemia in a patient of chronic rheumatoid arthritis is either related with the primary disease or due to the drugs which are used in the treatment like cyclophosphamide. In our present case, a 70-year-old female who was a known case of Rheumatoid Arthritis (RA) and was on methotrexate once a week orally for the past 20 years presented with complaints of loss of appetite, loss of weight and anaemia since 2 months. After thorough examination and investigation, she was diagnosed with acute myeloid leukaemia (AML-M4) with bilateral chest consolidation.

Addition of clonidine or lignocaine to ropivacaine for supraclavicular brachial plexus block: a comparative study

<p><b>INTRODUCTION</b>Clonidine is used with local anaesthetics to improve analgesia. However, the improvement conferred when clonidine is used together with ropivacaine is controversial. Thus, the present study aimed to evaluate the improvement in analgesia when clonidine is used together with ropivacaine for supraclavicular brachial plexus block.</p><p><b>METHODS</b>This was a prospective, randomised, double-blind controlled study. A total of 75 patients who were scheduled to undergo supraclavicular block were randomly assigned into three groups (i.e. clonidine, lignocaine and control groups) of 25. Patients in all three groups received 20 mL of 0.75% ropivacaine. In addition to that, patients in the clonidine group received 1 mL of clonidine (150 μg) plus 9 mL of saline, patients in the lignocaine group received 10 mL of 2% lignocaine with adrenaline (1:200,000), and patients in the control group received 10 mL of saline. The characteristics of anaesthesia and analgesia for these three groups were assessed.</p><p><b>RESULTS</b>The addition of 2% lignocaine with adrenaline to ropivacaine led to earlier onset of the sensory block (by 4.88 mins), but no increase in the duration of analgesia when compared to analgesia using ropivacaine alone. The addition of clonidine to ropivacaine led to earlier onset of sensory and motor blocks (by 2.88 mins and 3.28 mins, respectively), as well as an increased duration of sensory and motor blocks (by 222.64 mins and 192.92 mins, respectively) when compared to analgesia using ropivacaine alone. The total duration of analgesia was increased by 208.24 mins with clonidine when compared to analgesia using ropivacaine alone. There were no significant differences in sedation score and no side effects in all three groups.</p><p><b>CONCLUSION</b>When compared to the use of ropivacaine alone, the addition of 150 μg clonidine to ropivacaine for brachial plexus block achieved earlier analgesic onset and improved duration of analgesia, without unwanted side effects.</p>