Transitional metals and metal compounds have been used in versatile platforms for biomedical applications and therapeutic intervention. Severe side effects of anticancer drugs produce an urgent urge to develop new classes of anticancer agents with great potency as well as selectivity. In this background, recent studies demonstrate that monomeric manganese (MnII) thiocyanate complex (MMTC) holds great promise to exert effective antileukemic effects. MMTC was developed by a simple chemical reaction and characterized by elemental analyses, thermal analyses, and Fourier transform infrared (FTIR) spectroscopy. Anti-leukemic efficacy of the developed MMTC was estimated in KG-1A (AML) and K562 (CML) cell lines. Cell viability study, drug uptake assay, cellular redox balance (GSH and GSSG level), nitric oxide (NO) release level, reactive oxygen species (ROS) formation, alteration of mitochondrial membrane potential (MMP), and DNA fragmentation revealed that MMTC was able to produce significant antiproliferative effects on both cell lines at 25 μg mL−1 without showing any toxicological impact on normal lymphocytes. These findings will enlighten the biomedical application of manganese-based metal complexes as anti-leukemic agents.
Lampreys are representatives of an ancient vertebrate lineage that diverged from our own ~500 million years ago. By virtue of this deeply shared ancestry, the sea lamprey (P. marinus) genome is uniquely poised to provide insight into the ancestry of vertebrate genomes and the underlying principles of vertebrate biology. Here, we present the first lamprey whole-genome sequence and assembly. We note challenges faced owing to its high content of repetitive elements and GC bases, as well as the absence of broad-scale sequence information from closely related species. Analyses of the assembly indicate that two whole-genome duplications likely occurred before the divergence of ancestral lamprey and gnathostome lineages. Moreover, the results help define key evolutionary events within vertebrate lineages, including the origin of myelin-associated proteins and the development of appendages. The lamprey genome provides an important resource for reconstructing vertebrate origins and the evolutionary events that have shaped the genomes of extant organisms.
The anaesthesia gas supply system is designed to provide a safe, cost-effective and convenient system for the delivery of medical gases at the point of-use. The doctrine of the anaesthesia gas supply system is based on four essential principles: Identity, continuity, adequacy and quality. Knowledge about gas supply system is an integral component of safe anaesthetic practice. Mishaps involving the malfunction or misuse of medical gas supply to operating theatres have cost many lives. The medical gases used in anaesthesia and intensive care are oxygen, nitrous oxide, medical air, entonox, carbon dioxide and heliox. Oxygen is one of the most widely used gases for life-support and respiratory therapy besides anaesthetic procedures. In this article, an effort is made to describe the production, storage and delivery of anaesthetic gases. The design of anaesthesia equipment must take into account the local conditions such as climate, demand and power supply. The operational policy of the gas supply system should have a backup plan to cater to the emergency need of the hospital, in the event of the loss of the primary source of supply.
Cylinders; manifolds; medical gases; pipelines; vacuum-insulated evaporators
Correlation between the clinical and electroencephalogram-based monitoring has been documented sporadically during the onset of sedation. Propofol and midazolam have been studied individually using the observer's assessment of awareness/sedation (OAA/S) score and Bispectral index score (BIS). The present study was designed to compare the time to onset of sedation for propofol and midazolam using both BIS and OAA/S scores, and to find out any correlation.
A total of 46 patients (18-60 years, either sex, American Society of Anesthesiologists (ASA) I/II) posted for infraumbilical surgeries under spinal anaesthesia were randomly allocated to receive either injection propofol 1 mg/kg bolus followed by infusion 3 mg/kg/h (Group P, n=23) or injection midazolam 0.05 mg/kg bolus followed by infusion 0.06 mg/kg/h (Group M, n=23). Spinal anaesthesia was given with 2.5 ml to 3.0 ml of 0.5% bupivacaine heavy. When sensory block reached T6 level, sedation was initiated. The time to reach BIS score 70 and time to achieve OAA/S score 3 from the start of study drug were noted. OAA/S score at BIS score 70 was noted. Data from 43 patients were analyzed using SPSS 12 for Windows.
Time to reach BIS score 70 using propofol was significantly lower than using the midazolam (P<0.05). Time to achieve OAA/S score 3 using propofol was comparable with midazolam (P=0.358).
A divergence exists between the time to reach BIS score 70 and time to achieve OAA/S score 3 using midazolam, compared with propofol, during the onset of sedation.
Bispectral index score; midazolam; observer's assessment of awareness/sedation score; propofol; sedation
The study of immune related genes in lampreys and hagfish provides a unique perspective on the evolutionary genetic underpinnings of adaptive immunity and the evolution of vertebrate genomes. Separated from their jawed cousins at the stem of the vertebrate lineage, these jawless vertebrates have many of the gene families and gene regulatory networks associated with the defining morphological and physiological features of vertebrates. These include genes vital for innate immunity, inflammation, wound healing, protein degradation, and the development, signaling and trafficking of lymphocytes. Jawless vertebrates recognize antigen by using leucine-rich repeat (LRR) based variable lymphocyte receptors (VLRs), which are very different from the immunoglobulin (Ig) based T cell receptor (TCR) and B cell receptor (BCR) used for antigen recognition by jawed vertebrates. The somatically constructed VLR genes are expressed in monoallelic fashion by T-like and B-like lymphocytes. Jawless and jawed vertebrates thus share many of the genes that provide the molecular infrastructure and physiological context for adaptive immune responses, yet use entirely different genes and mechanisms of combinatorial assembly to generate diverse repertoires of antigen recognition receptors.
Adaptive immunity; Antigen receptor; Evolution; Jawless vertebrate; Leucine-rich repeat; Phylogeny; Somatic diversification; Variable Lymphocyte Receptor.
Immunoglobulins (or antibodies) are an essential element of the jawed vertebrate adaptive immune response system. These molecules have evolved over the past 500 million years and generated highly specialized proteins that recognize an extraordinarily large number of diverse substances, collectively known as antigens. During vertebrate evolution the diversification of the immunoglobulin-encoding loci resulted in differences in the genomic organization, gene content, and ratio of functional genes and pseudogenes. The tinkering process in the immunoglobulin-encoding loci often gave rise to lineage-specific characteristics that were formed by selection to increase species adaptation and fitness. Immunoglobulin loci and their encoded antibodies have been shaped repeatedly by contrasting evolutionary forces, either to conserve the prototypic structure and mechanism of action or to generate alternative and diversified structures and modes of function. Moreover, evolution favored the development of multiple mechanisms of primary and secondary antibody diversification, which are used by different species to effectively generate an almost infinite collection of diverse antibody types. This review summarizes our current knowledge on the genomics and evolution of the immunoglobulin-encoding loci and their protein products in jawed vertebrates.
Antibodies; gnathostomes; genomic organization; cladistic markers; microRNA; comparative genomics.
Sore throat and hoarseness are common complications of endotracheal intubation. It may be very distressing for the patient and may lead to sleep disturbances and unpleasant memories.
Materials and Methods:
This prospective double-blinded randomized control trial was aimed to determine the efficacy of prophylactic intravenous dexamethasone to reduce the incidence of postoperative sore throat at 1 hour after tracheal extubation. Ninety six patients of either sex aged between 18 to 60 years scheduled for elective surgeries needing general anesthesia with endotracheal intubation, were randomly allocated into two groups A and B. The patients received either intravenous 0.2 mg/kg dexamethasone (group A, n = 48) or normal saline (group B, n = 47) just before induction. Trachea was intubated with appropriate size disposable endotracheal tubes for securing the airway. Follow up for the incidence of sore throat, cough and hoarseness was done at 1, 6 and 24 hours post-extubation.
At 1 hour post-extubation, the incidence of sore throat in the control group was 48.9% compared with 18.8% in the dexamethasone group (P<0.002).
Prophylactic intravenous dexamethasone in a dose of 0.2 mg/kg can reduce the incidence of postoperative sore throat at 1 hour post-extubation by around 30%, with the efficacy being around 60%.
Intravenous dexamethasone; Intubation; Postoperative sore throat
Airway management in patients with faciomaxillary injuries is challenging due to disruption of components of upper airway. The anesthesiologist has to share the airway with the surgeons. Oral and nasal routes for intubation are often not feasible. Most patients have associated nasal fractures, which precludes use of nasal route of intubation. Intermittent intraoperative dental occlusion is needed to check alignment of the fracture fragments, which contraindicates the use of orotracheal intubation. Tracheostomy in such situations is conventional and time-tested; however, it has life-threatening complications, it needs special postoperative care, lengthens hospital stay, and adds to expenses. Retromolar intubation may be an option, But the retromolar space may not be adequate in all adult patients. Submental intubation provides intraoperative airway control, avoids use of oral and nasal route, with minimal complications. Submental intubation allows intraoperative dental occlusion and is an acceptable option, especially when long-term postoperative ventilation is not planned. This technique has minimal complications and has better patients’ and surgeons’ acceptability. There have been several modifications of this technique with an expectation of an improved outcome. The limitations are longer time for preparation, inability to maintain long-term postoperative ventilation and unfamiliarity of the technique itself. The technique is an acceptable alternative to tracheostomy for the good per-operative airway access.
Adult; intubation; intratracheal methods; maxillofacial injuries/surgery; oral/methods; surgery
Paediatric patients often present with different painful conditions that require immediate surgical interventions. Despite a plethora of articles on the ketamine–propofol combination, comprehensive evidence regarding the suitable sedoanalgesia regime is lacking due to heterogeneity in study designs.
This prospective, randomized, double-blind, active–controlled trial was conducted in 100 children, of age 3–14 years, American Society of Anesthesiologist physical status IE-IIE, posted for emergency short surgical procedures. Patients were randomly allocated to receive either 2 mL of normal saline (pre-induction) plus calculated volume of drug from the 11 mL of ketamine–propofol solution for induction (group PK, n=50) or fentanyl 1.5 μg/kg diluted to 2 mL with normal saline (pre-induction) plus calculated volume of drug from the 11 mL of propofol solution for induction (group PF, n=50). In both the groups, the initial bolus propofol 1 mg/kg i.v. (assuming the syringes contained only propofol, for simplicity) was followed by adjusted infusion to achieve a Ramsay Sedation Scale score of six. Mean arterial pressure (MAP) was the primary outcome measurement.
Data from 48 patients in group PK and 44 patients in group PF were available for analysis. Hypotension was found in seven patients (14.6%) in group PK compared with 17 (38.6%) patients in group PF (P=0.009). Intraoperative MAP was significantly lower in group PF than group PK when compared with baseline.
The combination of low-dose ketamine and propofol is more effective and a safer sedoanalgesia regimen than the propofol–fentanyl combination in paediatric emergency short surgical procedures in terms of haemodynamic stability and lesser incidence of apnoea.
Drug combinations; fentanyl; ketamine; paediatric emergency; procedural sedation; propofol
General anaesthesia is currently the conventional technique used for surgical treatment of breast lump. Paravertebral block (PVB) has been used for unilateral procedures such as thoracotomy, breast surgery, chest wall trauma, hernia repair or renal surgery.
We compared unilateral thoracic PVB with general anaesthesia (GA) in 60 consenting ASA physical status I and II female patients of 18–65 years age, scheduled for unilateral breast surgery. Patients were randomly assigned into two groups, P (n=30) or G (n=30), to receive either PVB or GA, respectively.
The average time to first post-operative analgesic requirement at visual analogue scale score≥4 (primary endpoint) was significantly longer in group P (303.97±76.08 min) than in group G (131.33±21.36 min), P<0.001. Total rescue analgesic (Inj. Tramadol) requirements in the first 24 h were 105.17±20.46 mg in group P as compared with 176.67±52.08 mg in group G (P<0.001). Significant post-operative nausea and vomiting requiring treatment occurred in three (10.34%) patients of the PVB group and eight (26.67%) patients in the GA group.
The present study concludes that unilateral PVB is more efficacious in terms of prolonging post-operative analgesia and reducing morbidities in patients undergoing elective unilateral breast surgery.
Unilateral breast surgery; anaesthetic technique; unilateral thoracic paravertebral block; general anaesthesia; post-operative analgesia; multiple-injection technique
To evaluate the free radical generation and antioxidant enzymes status in murine peritoneal macrophage during in vitro amikacin resistant Pseudomonas aeruginosa (ARPA) treatment with different time interval.
Peritoneal macrophages were treated with 1×108 CFU/mL ARPA cell suspension in vitro for different time interval (1, 2, 3, 6, 12, and 24 h) and super oxide anion generation, NO generation, reduced glutathione level and antioxidant enzymes status were analyzed.
Super oxide anion generation and NO generation got peak at 12 h, indicating maximal free radical generation through activation of NADPH oxidase in murine peritoneal macrophages during ARPA transfection. Reduced glutathione level and antioxidant enzymes status were decreased significantly (P<0.05) with increasing time of ARPA transfection. All the changes in peritoneal macrophages after 12 h in vitro ARPA transfection had significant difference (P<0.05).
From this study, it may be summarized that in vitro ARPA infection not only generates excess free radical but also affects the antioxidant system and glutathione cycle in murine peritoneal macrophage.
Antioxidant enzyme; ARPA; Oxidative stress; Peritoneal macrophage; Free radical generation
This randomized double blind study was started with an objective of management of spinal anaesthesia-induced hypotension in elective caesarean section by combining two commonly used vasopressors – ephedrine and phenylephrine in half of their usual doses with an expectation of reducing their foetomaternal side effects.
One hundred and thirty two patients were randomized into three groups to receive either 100 μg/ml phenylephrine (group-P, n=31) or 3 μg/ml ephedrine (group-E, n=33) or 50 mg phenylephrine plus 1.5 mg ephedrine/ml (group-PE, n=29). Immediately after spinal injection the study solution was started prophylactically in every patient at the rate of 40 ml/h. A predefined algorithm was used to adjust the infusion rate according to the systolic blood pressure (SBP).
Mean fall of SBP was significantly more in group-E than group-P (P=0.009) and group-PE (P=0.013). This was not significantly different when compared between group-P and group-PE (P=0.9). Episodes of hypotension and tachycardia were more in group-E than the other two groups. Statistically significant tachycardia was seen in Group-E than that in other two groups. Incidence of bradycardia and hypertension did not differ significantly among the groups. Maternal nausea and Apgar score were also comparable in three groups.
Current study claims that prophylactic phenylephrine 100 mg/ml is a better choice than ephedrine (3 mg/ml) or 50 mcg phenylephrine plus 1.5 mg ephedrine/ml in prevention of spinal anaesthesia-induced hypotension in elective caesarean section. Combination of two drugs in half the usual dose has no added advantage over phenylephrine, but this is better than ephedrine alone.
Bradycardia; elective caesarean section; hypotension; spinal anaesthesia; vasopressors
Defensin genes encode small cationic antimicrobial peptides that form an important part of the innate immune system. They are divided into three families, alpha (α), beta (β), and theta (θ), according to arrangement of the disulfide bonding pattern between cysteine residues. Considering the functional importance of defensins, investigators have studied the evolution and the genomic organization of defensin genes. However, these studies have been restricted mainly to β-defensins. To understand the evolutionary dynamics of α-defensin genes among primates, we identified the α-defensin repertoires in human, chimpanzee, orangutan, macaque, and marmoset. The α-defensin genes in primates can be classified into three phylogenetic classes (class I, II, and III). The presence of all three classes in the marmoset indicates that their divergence occurred before the separation of New World and Old World monkeys. Comparative analysis of the α-defensin genomic clusters suggests that the makeup of the α-defensin gene repertoires between primates is quite different, as their genes have undergone dramatic birth-and-death evolution. Analysis of the encoded peptides of the α-defensin genes indicates that despite the overall high level of sequence divergence, certain amino acid residues or motifs are conserved within and between the three phylogenetic classes. The evolution of α-defensins in primates, therefore, appears to be governed by two opposing evolutionary forces. One force stabilizes specific amino acid residues and motifs to preserve the functional and structural integrity of the molecules and the other diversifies the sequences generating molecules with a wide range of activities against a large number of pathogens.
alpha-defensin gene; primate evolution; innate immunity; comparative genomics; positive selection; birth-and-death evolution
Staphylococcus aureus is the most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Lymphocyte is an important immune cell. The aim of the present paper was to test the ameliorative role of nanoconjugated vancomycin against Vancomycin-sensitive Staphylococcus aureus (VSSA) and vancomycin-resistant Staphylococcus aureus (VRSA) infection-induced oxidative stress in lymphocytes. VSSA and VRSA infections were developed in Swiss mice by intraperitoneal injection of 5 × 106 CFU/mL bacterial solutions. Nanoconjugated vancomycin was adminstrated to VSSA- and VRSA-infected mice at its effective dose for 10 days. Vancomycin was adminstrated to VSSA- and VRSA-infected mice at a similar dose, respectively, for 10 days. Vancomycin and nanoconjugated vancomycin were adminstrated to normal mice at their effective doses for 10 days. The result of this study reveals that in vivo VSSA and VRSA infection significantly increases the level of lipid peroxidation, protein oxidation, oxidized glutathione level, nitrite generation, nitrite release, and DNA damage and decreases the level of reduced glutathione, antioxidant enzyme status, and glutathione-dependent enzymes as compared to control group, which were increased or decreased significantly near to normal in nanoconjugated vancomycin-treated group. These findings suggest the potential use and beneficial role of nanoconjugated vancomycin against VSSA and VRSA infection-induced oxidative stress in lymphocytes.
MicroRNAs 125a and 125b are predicted to be able to bind to the B lymphocyte-induced maturation protein-1 (BLIMP-1) and IFN regulatory protein-4 (IRF-4) transcription factors, which are essential for plasma cell differentiation. A computational survey of the human and mouse genomes revealed that miR-125a and miR-125b are members of a multigene family located in paralogous clusters. The miR-125a cluster on chromosome 19 in humans includes miR-99b and let-7e, whereas the miR-125b cluster on chromosome 21 includes miR-99a and miR-let-7c. Our analysis of the expression profiles for these six miRs during B lineage differentiation indicated that mature miR-125a, miR-125b, miR-99b and let-7e transcripts are preferentially expressed by the actively dividing centroblasts in germinal centers (GC). However, miR-99b and let-7e are not predicted to bind BLIMP-1 or IRF-4 transcripts, and binding to the untranslated region of BLIMP-1 and IRF-4 messenger RNAs could be confirmed only for miR-125b. When the effect of miR-125b over-expression on terminal B cell differentiation was evaluated in an LPS-responsive B cell line, the induction of BLIMP-1 expression and IgM secretion was inhibited in this model system. Furthermore, miR-125b over-expression inhibited the differentiation of primary B cells and compromised the survival of cultured myeloma cells. These findings suggest that miR-125b promotes B lymphocyte diversification in GC by inhibiting premature utilization of essential transcription factors for plasma cell differentiation.
BLIMP-1; centroblasts; gene regulation; IRF-4; MicroRNA; plasma cell differentiation
All jawed vertebrates produce immunoglobulins (IGs) as a defense mechanism against pathogens. Typically, IGs are composed of two identical heavy chains (IGH) and two identical light chains (IGL). Most tetrapod species encode more than one isotype of light chains. Chicken is the only representative of birds for which genomic information is currently available and is an exception to the above rule because it encodes only a single IGL isotype (i.e., lambda). Here, we show that the genome of zebra finch, another bird species, encodes a single IGL isotype, that is, lambda, like the chicken. These results strongly suggest that the second isotype (i.e., kappa) present in both reptiles and mammals was lost in a very early stage of bird evolution. Furthermore, we show that both chicken and zebra finch contain a single set of functional variable, joining, and constant region genes and multiple variable region pseudogenes. The latter finding suggests that this type of genomic organization was already present in the common ancestor of these bird species and remained unchanged over a long evolutionary time. This conservation is in contrast with the high levels of variation observed in the mammalian IGL loci. The presence of a single functional variable region gene followed by multiple variable pseudogenes in zebra finch suggest that this species may be generating antibody diversity by a gene conversion-like mechanism like the chicken.
immunoglobulin genes; cladistic molecular markers; antibody diversity; gene conversion; comparative genomics; repetitive elements
We have studied the genomic structure and evolutionary pattern of immunoglobulin kappa deleting element (KDE) and three kappa enhancers (KE5′, KE3′P, and KE3′D) in eleven mammalian genomic sequences. Our results show that the relative positions and the genomic organization of the KDE and the kappa enhancers are conserved in all mammals studied and have not been affected by the local rearrangements in the immunoglobulin kappa (IGK) light chain locus over a long evolutionary time (∼120 million years of mammalian evolution). Our observations suggest that the sequence motifs in these regulatory elements have been conserved by purifying selection to achieve proper regulation of the expression of the IGK light chain genes. The conservation of the three enhancers in all mammals indicates that these species may use similar mechanisms to regulate IGK gene expression. However, some activities of the IGK enhancers might have evolved in the eutherian lineage. The presence of the three IGK enhancers, KDE, and other recombining elements (REs) in all mammals (including platypus) suggest that these genomic elements were in place before the mammalian radiation.
Immunoglobulin kappa light chain; Kappa deleting element (KDE); Recombination signal sequence (RSS); Kappa enhancer; Transcription factor
The genomic organizations and functions of many miRNA genes have been described in recent years, but the origin and evolution of miRNAs in the exons of protein-coding genes are not well understood. The overlap of miR-650 genes with the protein-coding region of immunoglobulin lambda variable (IGVL) region genes has given a unique opportunity to witness a birth of miRNA gene. Both sequence comparisons and structure predictions indicate that the miR-650 genes are present in multiple copies and overlap in the same transcription orientation with the leader exon of primate IGVL genes of a specific phylogenetic clan (clan II). By reconstructing the phylogeny of the clan II IGVL genes, the stages in which the mutations accumulated in the leader exon and gave rise to a stable hairpin structure of miR-650 could be documented. The copy number variation of miR-650 genes among different species is the result of the duplication or deletion of the IGVL genes. To my knowledge, this is the first report of a genomic association between miRNA and the protein-coding genes of a multigene family. Analysis of the upstream region of the leader exon suggests that the IGVL and the mir-650 genes use the same promoter region for their transcription. However, in contrast to the general expectation about the expression of miRNAs that overlap with other genes in the same transcriptional orientation, this analysis provides evidence that the miR-650 gene is apparently transcribed independently of the IGVL gene with which it overlaps because they are expressed in different cell types.
micro-RNA evolution; immunoglobulin lambda variable region genes; micro-RNA host genes; micro-RNA transcription; overlapping genes; multigene family
Atrial fibrillation occurs frequently (2–20%) in chronic hyperthyroidism patients. Poorly treated thyrotoxic patients may present with a life-threatening cerebrovascular accident giving little scope to revert the situation. At times, it is difficult to make a patient euthyroid with conventional management. The definitive treatment of choice is 131I, radioiodine. An adjusted dose of an oral anticoagulant is highly efficacious for the prevention of all types of strokes. Timely intervention by a skilled airway manager with right instruments is the key to success in airway management. A 50-year-old thyrotoxic, semiconscious male presented with a sudden onset of haemiplegia. He had chronic AF, a huge thyroid swelling with gross tracheal deviation and dilated cardiomyopathy. A CT scan showed infarction in the left middle cerebral artery territory. After initial improvement with conservative management, patient’s condition deteriorated in the next 48 h. Repeat CT scan showed increase in the infarct size with haemorrhage and midline shift. Finally, he died despite all resuscitative measures.
Atrial fibrillation; anticoagulant; airway management; hyperthyroidism; ischaemic stroke
Clonidine has been used as adjuvant to local anesthetics in order to extend the duration of analgesia in various regional and central neuraxial blocks. It is previously reported that clonidine added to bupivacaine increases analgesia duration in brachial plexus block. We evaluated the effect of this combination in supraclavicular brachial plexus block for upper limb orthopedic procedures.
Materials and Methods:
A randomized double-blind placebo controlled trial was done with 70 patients of American Society of Anesthesiologists Grade I or II status undergoing upper limb orthopedic procedures. Group A (n = 35) patients received 25 ml of 0.5% bupivacaine and 0.2 ml (30 mcg) clonidine, whereas group B (n = 35) received 25 ml of 0.5% bupivacaine and 0.2 ml normal saline through a supraclavicular approach for brachial plexus block. Vital parameters were recorded 10 min prior to block placement and every 3 min thereafter till the end of the procedure. Onset and duration of both sensory and motor blocks and sedation score were recorded. All patients were observed in postanesthesia care unit and received tramadol injection as soon as they complained of pain as rescue analgesic. Duration of analgesia was taken as the time from placement of block till injection of rescue analgesic.
Analgesia duration was 415.4 ± 38.18 min (mean ± standard deviation) in Group A (clonidine) compared to 194.2 ± 28.74 min in Group B (control). No clinically significant difference was observed in heart rate, blood pressure, and oxygen saturation. Sedation score was higher in the clonidine group.
Addition of a small dose of clonidine to 0.5% bupivacaine significantly prolonged the duration of analgesia without producing any clinically important adverse reactions other than sedation.
Clonidine; bupivacaine; supraclavicular brachial plexus block; adjuvant; duration of analgesia; randomized controlled trial