Delay in diagnosis is the most important proximate reason for mortality in hereditary angio-oedema: our experience at Chandigarh, India

BACKGROUND

Hereditary angio-oedema (HAE) is a rare autosomal dominant disorder characterized clinically by recurrent episodes of nonpruritic subcutaneous and/or submucosal oedema. Laryngeal oedema is the commonest cause of mortality in patients with HAE. Prior to the availability of first-line treatment options for the management of HAE, mortality was as high as 30%. Mortality has significantly declined in countries where first-line treatment options are available and patients can access these therapies. There is a paucity of literature on the outcomes of patients with HAE in developing countries where availability of and access to first-line treatment options are still a challenge.

OBJECTIVES

To report our experience on mortality in patients with HAE and to report factors associated with the death of these patients.

METHODS

We carried out a record review of all patients diagnosed with HAE between January 1996 and August 2022. Families with HAE who had reported the death of at least one family member/relative from laryngeal oedema were studied in detail.

RESULTS

Of the 65 families (170 patients) registered in the clinic, 16 families reported the death of at least one family member/relative from laryngeal oedema (total of 36 deaths). Of these 16 families, 14 reported that 1 or more family members had experienced at least 1 attack of laryngeal oedema. One patient died during follow-up when she was taking long-term prophylaxis with stanozolol and tranexamic acid, while the remaining 35 patients were not diagnosed with HAE at the time of their death. At the time of death of all 36 patients, at least 1 other family member had symptoms suggestive of HAE, but the diagnosis was not established for the family.

CONCLUSIONS

To our knowledge, this is the largest single-centre cohort of patients with HAE in India reporting mortality data and factors associated with death in these families. The delay in diagnosis is the most important reason for mortality.

Transmission patterns of C1-INH deficiency hereditary angioedema favors a wild-type male offspring: Our experience at Chandigarh, India

BACKGROUND

Deficiency of C1-inhibitor (C1-INH) protein, caused by pathogenic variants in the Serpin family G member 1 (SERPING1) gene, is the commonest pathophysiological abnormality (in ∼95 % cases) in patients with hereditary angioedema (HAE). C1-INH protein provides negative control over kallikrein-kinin system (KKS). Although the inheritance of the HAE-C1-INH is autosomal dominant, female predominance has often been observed in patients with HAE.

OBJECTIVE

To analyze the risk of transmission of SERPING1 gene variant from father or mother to their offspring.

METHODS

Pedigree charts of 42 families with a confirmed diagnosis of HAE-C1-INH and a pathogenic variant in the SERPING1 gene were analysed. Patients with HAE who had had at least one child were included for analyses to assess the risk of transmission from the father or mother to their offspring.

RESULTS

Overall, 49 % (189/385) of all offspring inherited the genetic defect. In the subgroup analyses, 54.8 % (90/164) female offspring and 44.8 % (99/221; p < 0.02) male offspring inherited the genetic defect. Inheritance of the genetic defect was significantly lower in male offspring. Fathers with SERPING1 gene variant had a statistically significant skewed transmission of the wild type to the male offspring as compared to the variant (57.8 % wild type vs. 42.1 % variant; p < 0.02), whereas no statistically significant difference was found when a father transmitted the variant to a female offspring. Mothers with SERPING1 gene variant had no statistically significant difference in variant transmission to male or female offsprings.

CONCLUSION

Results of the study suggest that the transmission pattern of SERPING1 gene variant favours the transmission of wild-type alleles in males, especially when the father is the carrier; hence, overall, fewer males and more female offspring inherited the variant. This could be because of a selection of wild-type male sperms during spermatogenesis, as the KLK system has been reported to play a crucial role in the regulation of spermatogenesis. Although, a similar pattern was observed in the maternal transmission of the SERPING1 gene variant; the difference was not statistically significant, likely because of a small sample size.

Fatal COVID-19 Infection in Two Children with STAT1 Gain-of-Function

While SARS-CoV-2 infection causes a mild disease in most children, SARS-CoV-2 infection may be lethal in a few of them. In the defense against SARS-CoV-2, type I interferons are key players, and several studies have identified a defective or neutralized interferon response as the cause of overwhelming viral infection. However, inappropriate, untimely, or excessive interferon production may also be detrimental to the host. Here, we describe two patients with STAT1 gain-of-function (GOF), a known type I interferonopathy, who died of COVID-19. Whole-exome sequencing and interferon-gamma-activated sequence (GAS) and interferon-sensitive responsive element (ISRE) reporter assay were performed to identify and characterize STAT1 variants. Patient 1 developed hemophagocytic lymphohistiocytosis (HLH) in the context of COVID-19 infection and died in less than a week at the age of 4 years. Patient 2 developed a high fever, cough, and hypoxemia and succumbed to COVID-19 pneumonia at the age of 5 years. Two heterozygous missense variants, p.E563Q and p.K344E, in STAT1 were identified. Functional validation by reporter assay and immunoblot confirmed that both variants are gain-of-function (GOF). GOF variants transiently expressing cells exhibited enhanced upregulation of downstream genes, including ISG15, MX1, and OAS1, in response to IFN-α stimulation. A catastrophic course with HLH or acute respiratory failure is thought to be associated with inappropriate immunoregulatory mechanisms to handle SARS-CoV-2 in STAT1 GOF. While most patients with inborn errors of immunity who developed COVID-19 seem to handle it well, these cases suggest that patients with STAT1-GOF might be at risk of developing fatal complications due to SARS-CoV-2.

Folate Deficiency: A Possible Association with Congenital Heart Defects

Congenital heart defects continue to remain a major cause of serious morbidity and mortality, especially in the developing world. This study was planned to get some insight into the role of modifiable nutritional elements in structural CHD etiology. This cross-sectional, observational study was conducted at a hospital in Northern India from January 2017 to December 2017. Infants < 6 mo with structural CHD as cases and those without structural heart disease were enrolled as controls. Blood samples were collected from mother-child pairs and tested for serum folate, vitamin B12, and homocysteine. It was found that 46.7% infant-mother pairs, out of 45 in the cases group had folate deficiency, whereas in the control group, only 20% had folate deficiency, which was statistically significant (p = 0.013). Baby (0-6 mo) with congenital heart defects (CHD) and their mothers are more likely to have low folate levels compared to those not having CHD.

Case report: Corticosteroids as an adjunct treatment for the management of liver abscess in Papillon-Lefèvre syndrome: A report on two cases

Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive disorder characterized clinically by palmoplantar keratoderma, periodontitis, and recurrent pyogenic infections. Liver abscess is rarely reported in patients. The use of corticosteroids for the treatment of liver abscess akin to chronic granulomatous disease (CGD) has not been reported previously. Here, we report 2 cases of liver abscess in PLS that responded to corticosteroids.

Hypnosis and progressive muscle relaxation for anxiolysis and pain control during extraction procedure in 8-12-year-old children: a randomized control trial

Introduction

Hypnosis (H) and Progressive Muscle Relaxation (PMR) have proven to be effective in a variety of medical settings; there is a paucity of their practical application in paediatric dentistry. The study aimed to comparatively evaluate the role of H and PMR on anxiety, heart rate (HR), oxygen saturation (SPO₂), blood pressure (BP), pain, and analgesic requirement during extraction in children.

Materials and methods

Sixty children aged 8–12 years undergoing primary molar extractions were randomly allocated to three groups—H, PMR, and control (C). The anxiety (proposed Visual Facial Anxiety scale), HR, and SPO₂ were measured pre/post-operatively with/without interventions (H, PMR, C) at 4 intervals. The BP and pain (Wong-Baker faces pain scale) were recorded pre- and post-operatively. Need for analgesic post-operatively was assessed.

Results

Statistically significant reduction in anxiety was noted post-extraction in H (0.30 ± 0.80), PMR (0.50 ± 0.69) (p < 0.001*). HR showed a statistically significant drop after H, PMR application. (p < 0.001*) No significant difference in SPO₂ was noted in the three groups (p > 0.05). Pain control was well achieved using H (85%), PMR (70%); BP was well-regulated in the H, PMR compared to C group (p < 0.001*). Need for analgesics was reduced in H (45%), PMR (50%) versus C (100%). Both techniques H, PMR were comparable in all measures.

Conclusion

Hypnosis and PMR are effective techniques for anxiolysis and pain control in paediatric dental patients.

Middle Meningeal Artery Embolization Using Combined Particle Embolization and n-BCA with the Dextrose 5% in Water Push Technique for Chronic Subdural Hematomas: A Prospective Safety and Feasibility Study

BACKGROUND AND PURPOSE

Embolization of the middle meningeal artery for treatment of refractory or recurrent chronic subdural hematomas has gained momentum during the past few years. Little has been reported on the use of the n-BCA liquid embolic system for middle meningeal artery embolization. We present the technical feasibility of using diluted n-BCA for middle meningeal artery embolization.

MATERIALS AND METHODS

We sought to examine the safety and technical feasibility of the diluted n-BCA liquid embolic system for middle meningeal artery embolization. Patients with chronic refractory or recurrent subdural hematomas were prospectively enrolled from September 2019 to June 2020. The primary outcome was the safety and technical feasibility of the use of diluted n-BCA for embolization of the middle meningeal artery. The secondary end point was the efficacy in reducing hematoma volume.

RESULTS

A total of 16 patients were prospectively enrolled. Concomitant burr-hole craniotomies were performed in 12 of the 16 patients. Two patients required an operation following middle meningeal artery embolization for persistent symptoms. The primary end point was met in 100% of cases in which there were no intra- or postprocedural complications. Distal penetration of the middle meningeal artery branches was achieved in all the enrolled cases. A 7-day post-middle meningeal artery embolization follow-up head CT demonstrated improvement (>50% reduction in subdural hematoma volume) in 9/15 (60%) patients, with 6/15 (40%) showing an unchanged or stable subdural hematoma. At day 21, available CT scans demonstrated substantial further improvement (>75% reduction in subdural hematoma volume).

CONCLUSIONS

Embolization of the middle meningeal artery using diluted n-BCA and ethiodized oil (1:6) is safe and feasible from a technical standpoint. The use of a dextrose 5% bolus improves distal penetration of the glue.

Molecular dynamics modeling of lithium ion intercalation induced change in the mechanical properties of LixMn2O4

The objective of this study is to understand the fracture mechanisms in the lithium manganese oxide (LiMn₂O₄) electrode at the molecular level by studying mechanical properties of the material at different values of the State of Charge (SOC) using the principles of molecular dynamics (MD). A 2 × 2 × 2 cubic structure of the LiMn₂O₄ unit cell containing eight lithium ions, eight trivalent manganese ions, eight tetravalent manganese ions, and 32 oxygen ions is studied using a large-scale atomic/molecular massively parallel simulator. As part of the model validation, the lattice parameter and volume changes of Li_xMn₂O₄ as a function of SOC (0 < x < 1) have been studied and validated with respect to the experimental data. This validated model has been used for a parametric study involving the SOC value, strain rate (charge and discharge rate), and temperature. The MD simulations suggest that the lattice constant varies from 8.042 Å to 8.235 Å during a full discharging cycle, in agreement with the experimental data. The material at higher SOC shows more ductile behavior compared to low SOC values. Furthermore, yield and ultimate stresses are less at lower SOC values except when SOC values are within 0.125 and 0.375, verifying the phase transformation theory in this range. The strain rate does not affect the fully intercalated material significantly but seems to influence the material properties of the partially charged electrode. Finally, a study of the effect of temperature suggests that diffusion coefficient values for both high and low-temperature zones follow an Arrhenius profile, and the results are successfully explained using the vacancy diffusion mechanism.

Microstructural and Compositional Characterisation of Electronic Materials

<p class="p1"> </p><p class="p2"><span class="s1"> </span>Microstructural and compositional characterisation of electronic materials in support of the development of GaAs, GaN, and GaSb based multilayer device structures is described. Electron microscopy techniques employing nanometer and sub-nanometer scale imaging capability of structure and chemistry have been widely used to characterise various aspects of electronic and optoelectronic device structures such as InGaAs quantum dots, InGaAs pseudomorphic (pHEMT), and metamorphic (mHEMT) layers and the ohmic metallisation of GaAs and GaN high electron mobility transistors, nichrome thin film resistors, GaN heteroepitaxy on sapphire and silicon substrates, as well as InAs and GaN nanowires. They also established convergent beam electron diffraction techniques for determination of lattice distortions in III-V compound semiconductors, EBSD for crystalline misorientation studies of GaN epilayers and high-angle annular dark field techniques coupled with digital image analysis for the mapping of composition and strain in the nanometric layered structures. Also, <em>in-situ </em>SEM experiments were performed on ohmic metallisation of pHEMT device structures. The established electron microscopy expertise for electronic materials with demonstrated examples is presented.</p>

A Five-Year Study of Intrapleural Fibrinolytic Therapy in Loculated Pleural Collections

BACKGROUND

Pleural fluid loculations due to complicated parapneumonic effusion (CPE), empyema, tubercular effusion and traumatic hemothorax can be managed either by video-assisted thoracoscopic surgery (VATS) or intrapleural ibrinolytic therapy (IPFT). The former is more invasive, not easily available and is also more expensive. On the other hand, IPFT is less invasive, cheaper, easily accessible and if used early, in loculated pleural collections, break loculations and early pleural peel, thereby facilitating pleural space drainage.

OBJECTIVE

To study the efficacy of IPFT in facilitating pleural space drainage in loculated pleural collections of diverse aetiologies.

METHODS

A five-year retrospective, observational study of 200 patients, with loculated pleural collections and failed tube drainage and managed with IPFT was carried out. Responders were defined as those with significant volume of fluid drained and significant radiological resolution.

RESULTS

There were 106 (53%) cases of CPE, 59 (29.5%) cases of tubercular effusion, 23 (11.5%) cases of empyema and 12 (6%) cases of hemothorax. Responders were 148 (74%) in number. The distribution of responders as per type of loculated pleural collection was as follows: CPE 88 (83%), tubercular 37 (62.7%), empyema 14 (60.8%) and traumatic hemothorax 11 (91.6%). The adverse effects were mild and included chest pain in six patients and low-grade transient fewer in three cases.

CONCLUSIONS

Intrapleural fibrinolytic therapy is a safe and cost-effective option in the management of selected patients with loculated pleural effusions.

Study of Self-Induced Growth of AlGaAs Nanoneedles on Silicon Substrates Using Metal Organic Chemical Vapor Deposition Technique

A simple catalyst free growth method was used for the growth of single crystalline AlGaAs nanoneedles on Si substrate by metal organic chemical vapor deposition (MOCVD) technique. The growth mechanism of catalyst free growth of nanoneedles was investigated. The effect of growth rate, growth temperature and V/III ratio was studied in detail. The growth of nanoneedles required a careful optimization of the growth conditions. The formation of well-faceted nanoneedles with hexagonal cross-section was found to be influenced by the growth parameters. Based on these studies, the growth mechanism has been explained using nucleation theory. The growth of nanoneedles was believed to proceed via Vapor-Solid (VS) growth mechanism after the initial AlGaAs cluster formation depending on the growth conditions.

Prospective glioma grading using single-dose dynamic contrast-enhanced perfusion MRI

AIM

To evaluate the sensitivity and specificity of single-dose dynamic contrast-enhanced (DCE) perfusion magnetic resonance imaging (MRI) in prospective evaluation of glioma grading and to correlate the relative cerebral blood volume (rCBV) values with mitotic and ki-67 indexes obtained at histopathology.

MATERIALS AND METHODS

A total of 53 histologically proven patients with glioma were included in this study. DCE-MRI perfusion with a single dose of contrast medium was included in brain tumour protocol and prospective grading of glioma into low and high grade was done based on a previously reported rCBV cut-off value of 3. Tumours with rCBV ≥ 3 were considered to be high grade and rCBV < 3 were considered to be low grade. The sensitivity and specificity of the cut-off value were estimated. Ki-67 and mitotic indexes were also obtained on histopathological analysis along with histological grading.

RESULTS

Based on pre-defined rCBV cut-off values, prospective grading of low- and high-grade glioma was achieved with a sensitivity and specificity of 97.22% and 100%, respectively. Significant correlation was found between the mitotic/ki-67 indexes and rCBV values when data for high- and low-grade tumours was combined.

CONCLUSION

DCE-MRI performed with a single dose of contrast medium is as effective as a protocol with a double-dose of contrast medium for glioma grading using 3 T MRI and could be added to the routine evaluation protocol of brain tumours.

Diagnostic Utility of Biomarkers in COPD

BACKGROUND

COPD will become the third leading cause of death by 2020. There are many situations in which spirometry, the primary tool for diagnosis of COPD, cannot be performed, and thus, the staging and status of these patients cannot be determined. To date, there is no known biochemical marker used for diagnosing COPD. This study aimed to explore the utility of biomarkers for diagnosis of COPD.

METHODS

This was an observational study composed of 96 stable subjects with COPD and 96 subjects with normal lung function. Each group contained an equal number of smokers and nonsmokers. Serum levels of superoxide dismutase 3, glutathione peroxidase, catalase, ceruloplasmin ferroxidase activity, C-reactive protein, and surfactant protein D (SPD) were estimated. Ferroxidase activity was estimated by a kinetic method, whereas the other analytes were measured by enzyme-linked immunosorbent assay. The cutoff value, sensitivity and specificity at the cutoff value, and area under the curve for each analyte were determined from receiver operating characteristic curve.

RESULTS

Significantly decreased superoxide dismutase 3 and increased ferroxidase activity, SPD, glutathione peroxidase, and C-reactive protein levels were found in subjects with COPD. For all subjects and nonsmoking subjects with COPD, the area under the curve was highest for ferroxidase activity, followed by glutathione peroxidase, SPD, and C-reactive protein, with a sensitivity and specificity of > 73%. For smoking subjects with COPD, the area under the curve was highest for SPD, followed by glutathione peroxidase, ferroxidase activity, and C-reactive protein, with a sensitivity and specificity > 67%. Some combinations of markers were found to give either a sensitivity or specificity of > 95%, which can be utilized to rule in and rule out COPD.

CONCLUSIONS

Biomarkers can be reliably utilized in the diagnosis of COPD. Of all the markers, SPD appears to be the most promising in smokers, whereas ferroxidase activity shows promise in nonsmokers. To rule out COPD, ferroxidase activity or glutathione peroxidase can be potentially useful, whereas to rule in COPD, ferroxidase activity and glutathione peroxidase appear to be the most promising combination in both nonsmoking and smoking subjects.

Synthesis of Bisphosphodiester Surfactants Derived from Tetradecanol and Different Methylene Chains as a Spacer Derived from α-ω-Alkyl Dibromides

Bisphosphodiester surfactant is a name assigned to a family of synthetic amphiphiles possessing a hydrocarbon chain attached to another hydrocarbon chain via different methylene chains as a spacer derived from α-ω-alkyl dibromide (1,4-DBB, 1,6-DBH and 1,8-DBO). In the present study, a series of bisphosphodiester surfactants having C14 hydrophobic tail and different methylene chains as a spacer derived from α-ω-alkyl dibromide have been synthesized at 35°C. The effect of reaction variables like temperature, duration and molar ratios of mono tetradecyl phosphate, tetramethyl ammonium hydroxide and spacer on the yield of bisphosphodiester surfactants has also been reported. Modern instrumental techniques viz. FT-IR, 1HNMR, and 13CNMR were utilized to characterize the functional groups presence in synthesized bisphosphodiester surfactants. Elemental analysis of synthesized bisphosphodiester surfactants was also carried out. Surface active properties viz. surface tension, interfacial tension, critical micelle concentration and aqueous properties viz. foaming stability, wetting ability, emulsifying ability and dispersing power of synthesized gemini surfactants were also determined. Among all synthesized bisphosphodiester surfactants IIIb had maximum anionic content of 78.9%; and showed highest foaming ability (70 ml), superior dispersing ability (45.7%), whereas IIIc showed low CMC values (0.00026 mmol/l); minimum surface tension and interfacial tension (37.3 mN/m and 31.6 mN/m) respectively.

Synthesis, Structural Properties and Applications of Gemini Surfactants: A Review

Gemini surfactants are most exciting new types of surfactants. They have two hydrophilic head groups and two hydrophobic groups in a molecule separated by a spacer group. Nowadays different types of geminis have been synthesized. Geminis show some characteristic features like low cmc, high surface activity, high solubility in water, good foaming and wetting properties, as well as low Krafft temperature. Geminis imply low eye and skin irritation. These surfactants are widely used as antifoaming and antimicrobial agents. This review paper deals with synthesis, properties and applications of various gemini surfactants.

Synthesis and Properties of Di-n-hexadecyl-α,ω-Alkyl Bisphosphate Surfactants

Amphipatic compounds with connecting group between two lipophilic groups were prepared by phosphorylating a long chain alcohol (hexadecanol) with pyrophosphoric acid to prepare hexadecyl phosphate. Then the resulting hexadecyl phosphate was used to prepare bisphosphate surfactants with terminal dibromo alkanes viz. 1,4-dibromo butane or 1,6-dibromo hexane or 1,8-dibromo octane using acetonitrile as solvent. The structure of synthesized products were verified by modern analytical techniques viz. FT-IR, and 1H-NMR. The disodium salts of bisphosphate surfactants were obtained by neutralization of free acid with sodium hydroxide. The performance properties viz. foaming, wetting, emulsifying ability and anionic content of synthesized surfactants were also evaluated. The synthesized bisphosphate surfactant with 1,6-dibromo hexane possessed maximum anionic content and showed good water solubility, foaming, wetting, and emulsifying ability compared to conventional analogs.

Growth of aluminum catalyzed AlGaAs nanowires on silicon substrate

Aluminum catalyzed AlGaAs nanowires were fabricated on Si (111) substrates using metal-organic chemical vapor deposition (MOCVD) technique at a low growth temperature of 450 degrees C. Grown structures were characterized by field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectroscopy (EDS) and photoluminescence (PL) techniques. Nanowire clusters were observed all over the substrate. Multiprong root-grown AlGaAs nanowire clusters as well as catalyst particle terminated growth was observed. The growth is explained by Vapor-Solid-Solid (VSS) and Vapor-Solid (VS) growth mechanisms using Al-Si binary phase diagram. EDS and PL measurement confirm the formation of AlGaAs nanowires.

The prevalence of nursing caries in Davangere preschool children and its relationship with feeding practices and socioeconomic status of the family

The aim of the present study was to find the prevalence of nursing caries in Davangere preschool children and its relationship with feeding practices and socioeconomic status of the family.

MATERIALS AND METHODS

A total of 813 children aged 2-6 years were screened for the present study from randomly selected three kindergarten schools each from Government, Government aided, and private managements. Clinical examination was done inside the respective schools. At the time of examination, a proforma was filled for each child comprising of DFS index. The questionnaire by Winter et al. was modified and used in this study. The completed proformas were statistically analyzed to find if any correlation existed between the nursing caries to the feeding practices and socioeconomic status of the family.

RESULTS

Duration of breastfeeding increases the number of children with nursing caries and the mean DFS. There is a strong and significant relationship between the severity of nursing caries and the degree of feeding abuse. Children from low socioeconomic status have increased early childhood caries.

CONCLUSION

The prevalence of nursing caries was 19.2% in Davangere preschool population. Nursing caries were more in children who were taking a feeding bottle to bed at night and were increasingly seen in large families and lower socioeconomic groups.

Inhibitors of cyclin dependent kinases: useful targets for cancer treatment

Cancer drug discovery is one of the most rapidly changing areas of pharmaceutical research. Uncontrolled proliferation is a hallmark of cancer cells. Over the past two decades, it has become increasingly clear that in many human cancers, hyperactivity of Cyclin Dependent Kinases (CDKs) is one of the mechanisms underlying the physiological hyper-proliferation. CDKs are serine/threonine protein kinases, which play an important role in cell-cycle regulation. Their sequential activation ensures, the correct timing and ordering of events required for cell cycle progression. Therefore, inhibition of CDKs, through the insertion of small molecules into its ATP binding pocket has emerged as a potential therapy method for cancers. Consequently, a number of small molecules with CDK inhibitory properties have been developed. Many of these have been evaluated as potent inhibitors and some are currently in clinical-trials for various types of cancer. This review reports various CDK inhibitors, natural as well as small molecules, along with their reported activities for various CDKs. It will highlight the potential for the development of novel anti-cancer molecules.

Hypertonic saline: a clinical review

Literature suggest that hypertonic saline (HTS) solution with sodium chloride concentration greater than the physiologic 0.9% can be useful in controlling elevated intracranial pressure (ICP) and as a resuscitative agent in multiple settings including traumatic brain injury (TBI). In this review, we discuss HTS mechanisms of action, adverse effects, and current clinical studies. Studies show that HTS administered during the resuscitation of patients with a TBI improves neurological outcome. HTS also has positive effects on elevated ICP from multiple etiologies, and for shock resuscitation. However, a prospective randomized Australian study using an aggressive resuscitation protocol in trauma patients showed no difference in amount of fluids administered during prehospital resuscitation, and no differences in ICP control or neurological outcome. The role of HTS in prehospital resuscitation is yet to be determined. The most important factor in improving outcomes may be prevention of hypotension and preservation of cerebral blood flow. In regards to control of elevated ICP during the inpatient course, HTS appears safe and effective. Although clinicians currently use HTS with some success, significant questions remain as to the dose and manner of HTS infusion. Direct protocol comparisons should be performed to improve and standardize patient care.

Efficacy of three doses of tramadol with bupivacaine for caudal analgesia in paediatric inguinal herniotomy

BACKGROUND

This study was designed to evaluate the analgesic efficacy of three doses of tramadol, administered caudally with bupivacaine, in providing postoperative pain relief in children.

METHODS

Eighty children, aged between 2 and 8 yr, undergoing inguinal herniotomy were randomly allocated to receive bupivacaine 0.25% 0.75 ml kg(-1) (Group B; n=20), bupivacaine 0.25% 0.75 ml kg(-1) with tramadol 1 mg kg(-1) (Group BT1; n=20), bupivacaine 0.25% 0.75 ml kg(-1) with tramadol 1.5 mg kg(-1) (Group BT1.5; n=20), or bupivacaine 0.25% 0.75 ml kg(-1) with tramadol 2 mg kg(-1) (Group BT2; n=20) by the caudal route immediately after induction of general anaesthesia. Heart rate, arterial pressure and oxygen saturation were monitored. Postoperative pain was assessed at regular intervals for 24 h using All India Institute of Medical Sciences pain score. Analgesia was supplemented whenever pain score was >or=4. Duration of analgesia and requirement for additional analgesics was noted.

RESULTS

Duration of analgesia was longer in Group BT2 [(mean (SD) 12 (0.9) h] compared with Group B [4 (1) h], Group BT1 [8 (0.9) h], or Group BT1.5 [11 (1) h]; all P<0.001. Total consumption of rescue analgesic was significantly lower in group BT2 compared with other groups (P<0.001). There were no significant changes in heart rate, arterial pressure and oxygen saturation between groups. Adverse effects were not observed.

CONCLUSIONS

Caudal tramadol 2 mg kg(-1), combined with bupivacaine 0.25% 0.75 ml kg(-1), provided longer duration of postoperative analgesia and reduced requirement for rescue analgesic compared with tramadol 1 mg kg(-1) or 1.5 mg kg(-1) in children undergoing inguinal herniotomy.

Protective role of certain chemicals against UV-B-induced damage in the nitrogen-fixing cyanobacterium, Nostoc muscorum

The protective effects of L-cysteine, ascorbic acid, reduced glutathione, L-tryptophan, and sodium pyruvate against UV-B-induced damages were studied in the nitrogen-fixing cyanobacterium, Nostoc muscorum. When added to the culture suspension during UV-B treatment, these chemicals caused a significant protective effect on survival and growth of the organism. Sodium pyruvate conferred the strongest protection whereas the weakest effect was elicited by tryptophan. A 20 min exposure of a culture suspension to UV-B completely inactivated nitrogenase activity but the inactivation was strongly prevented by exogenous addition of ascorbic acid or reduced glutathione during UV-B exposure, and weakly prevented by pyruvate, cysteine and tryptophan. In vivo nitrate reductase activity was not completely lost even after 80 min of UV-B exposure, and addition of the test chemicals did not confer any significant protection to this enzyme. Whereas (14)CO(2) uptake was drastically inhibited (78% inhibition) by 30 min exposure to UV-B in the absence of any test chemical, about 76% activity remained when the UV-B exposure was given to cultures in the presence of ascorbic acid. These results suggest that the damaging effects of UV-B are substantially minimized by certain reducing agents, the protective effect being particularly strong on the O(2) sensitive enzyme, nitrogenase. Presence of these chemicals in their natural habitat or inside the cells of living organisms may partially protect/repair the damaging effects of UV-B radiation.

The gene for the axonal cell adhesion molecule TAX-1 is amplified and aberrantly expressed in malignant gliomas

The human TAX-1 gene encodes a Mr 135,000 glycoprotein that is transiently expressed on the surface of a subset of neurons during development and is involved in neurite outgrowth. The TAX-1 gene has been mapped to a region on chromosome 1 that has been implicated in microcephaly and the Van der Woude syndrome. Using restriction landmark genome scanning to search for amplified genes in gliomas, we found TAX-1 to be amplified in 2 high-grade gliomas among a group of 26 gliomas investigated. Real-time reverse transcription-quantitative PCR analysis detected high levels of TAX-1 mRNA in glial tumors, even in the absence of TAX-1 gene amplification. Immunohistochemical analysis revealed abundant levels of TAX-1 in neoplastic glial cells of glioblastoma multiforme tumors. Because glial tumors are highly invasive and in view of the role of TAX-1 in neurite outgrowth, we investigated the potential role of TAX-1 in glioma cell migration. Using an in vitro assay, we found that the migration of glioma tumor cells is profoundly reduced in the presence of either an anti-TAX-1 antibody or a TAX-1 antisense oligonucleotide. Our findings suggest that TAX-1 plays a role in glial tumorigenesis and may provide a potential target for therapeutic intervention.

Enhancement of catalytic activity of enzymes by heating in anhydrous organic solvents: 3D structure of a modified serine proteinase at high resolution

For the first time, it is demonstrated that exposure of an enzyme to anhydrous organic solvents at optimized high temperature enhances its catalytic power through local changes at the binding region. Six enzymes, namely, proteinase K, wheat germ acid phosphatase, alpha-amylase, beta-glucosidase, chymotrypsin and trypsin were exposed to acetonitrile at 70 degrees C for three hr. The activities of these enzymes were found to be considerably enhanced. In order to understand the basis of this change in the activity of these enzymes, proteinase K was analyzed in detail using X-ray diffraction method. The overall structure of the enzyme was found to be similar to the native structure in aqueous environment. The hydrogen bonding system of the catalytic triad remained intact after the treatment. However, the water structure in the substrate binding site underwent some rearrangement as some of the water molecules were either displaced or completely absent. The most striking observation concerning the water structure was the complete deletion of the water molecule which occupied the position at the so-called oxyanion hole in the active site of the native enzyme. Three acetonitrile molecules were found in the present structure. All the acetonitrile molecules were located in the recognition site. Interlinked through water molecules, the sites occupied by acetonitrile molecules were independent of water molecules. The acetonitrile molecules are involved in extensive interactions with the protein atoms. The methyl group of one of the acetonitrile molecules (CCN1) interacts simultaneously with the hydrophobic side chains of Leu 96, Ile 107 and Leu 133. The development of such a hydrophobic environment at the recognition site introduced a striking conformation change in Ile 107 by rotating its side chain about C alpha-C beta bond by 180 degrees to bring about the delta-methyl group within the range of attractive van der Waals interactions with the methyl group of CCN1. A similar change had earlier been observed in proteinase K when it was complexed to a substrate analogue, lactoferrin fragment.

Enhancement of catalytic efficiency of enzymes through exposure to anhydrous organic solvent at 70 degrees C. Three-dimensional structure of a treated serine proteinase at 2.2 A resolution

The enzyme behavior in anhydrous media has important applications in biotechnology. So far chemical modifications and protein engineering have been used to alter the catalytic power of the enzymes. For the first time, it is demonstrated that an exposure of enzyme to anhydrous organic solvents at optimized high temperature enhances its catalytic power through local changes at the binding region. Six enzymes: proteinase K, wheat germ acid phosphatase, alpha-amylase, beta-glucosidase, chymotrypsin and trypsin have been exposed to acetonitrile at 70 degrees C for three hours. The activities of these enzymes were found to be considerably enhanced. In order to understand the basis of this change in the activity of these enzymes, the structure of one of these treated enzymes, proteinase K has been analyzed in detail using X-ray diffraction method. The overall structure of the enzyme is similar to the native structure in aqueous environment. The hydrogen bonding system of the catalytic triad is intact after the treatment. However, the water structure in the substrate binding site undergoes some rearrangement as some of the water molecules are either displaced or completely absent. The most striking observation concerning the water structure pertains to the complete deletion of the water molecule which occupied the position at the so-called oxyanion hole in the active site of the native enzyme. Three acetonitrile molecules were found in the present structure. All the acetonitrile molecules are located in the recognition site. The sites occupied by acetonitrile molecules are independent of water molecules. The acetonitrile molecules are involved in extensive interactions with the protein atoms. All of them are interlinked through water molecules. The methyl group of one of the acetonitrile molecules (CCN1) interacts simultaneously with the hydrophobic side chains of Leu-96, Ile-107, and Leu-133. The development of such a hydrophobic environment at the recognition site introduces a striking conformation change in Ile-107 by rotating its side chain about C(alpha)--C(beta) bond by 180 degrees to bring about the delta-methyl group within the range of attractive van der Waals interactions with the methyl group of CCN1. A similar change has earlier been observed in proteinase K when it is complexed to a substrate analog lactoferrin fragment.

Carbodi-imide coupling of enzymes to the reversibly soluble insoluble polymer Eudragit S-100

The coupling of proteins and enzymes to soluble-insoluble polymers by carbodi-imide can be performed by using numerous variations of the protocol. This protocol has been investigated for the coupling of five different enzymes, namely wheatgerm acid phosphatase, beta-glucosidase, beta-galactosidase, trypsin and xylanase, to an enteric methacrylate polymer Eudragit S-100. The following results were found. (1) The activity of the bioconjugate was critically dependent on the physical state of the polymer and the pH of the coupling reaction. For example, in the case of wheatgerm acid phosphatase, the activity of the bioconjugate was 49% when coupling was performed at pH 7.2 and 67% when coupling was performed at pH 4. 5. With beta-galactosidase the corresponding values were 57% and 23% and with beta-glucosidase they were 57% and 52% respectively. (2) In some cases, such as beta-glucosidase and beta-galactosidase, it might be necessary to remove excess carbodi-imide before the addition of the enzyme to the activated matrix. (3) In most of the cases investigated, a sig-nificant amount of the enzyme (more than 90%) could be bound to the matrix merely by adsorption. (4) More importantly, after the carbodi-imide coupling procedure, a sufficient fraction of the bound enzyme could be eluted off the matrix, indicating that this was merely adsorbed and not covalently coupled.

GAC1, a new member of the leucine-rich repeat superfamily on chromosome band 1q32.1, is amplified and overexpressed in malignant gliomas

We have used two-dimensional electrophoresis of enzyme-digested genomic DNA to identify a novel gene GAC1, which maps at 1q32.1 and which is overexpressed in malignant gliomas in which it is amplified. GAC1 encodes a protein which belongs to the leucine-rich repeat superfamily. Amplification and overexpression of GAC1 was demonstrated in two of eight tumors where amplifications were previously evidenced by comparative genomic hybridization (one glioblastoma multiforme and one anaplastic astrocytoma), and in one of eight unselected glioblastomas multiforme. GAC1 exhibits sequence homology with other proteins which function as cell-adhesion molecules or as signal transduction receptor and is a likely candidate for the target gene in the 1q32.1 amplicon in malignant gliomas.

Synthesis and anti-inflammatory activity of some potential cyclic phenothiazines

Some new schiff's bases (IVa-IVe), thiazolidinones (Va-Ve), delta 2-triazolines (VIa-VIe) and formazans (VIIa-VIIe) of 2-chlorophenothiazine have been synthesized and screened against Carrageenin induced oedema in albino rats. Some compounds of the series have shown promising activity. The most active compound is 2-chloro-10[5-(2-fluorophenyl-2-oxo-4 thiazolidin-1-yl)-amino acetyl] phenothiazine was found to be most potent. This compound (Vb) was further evaluated in detail and compared with phenylbutazone for its relative anti inflammatory potency (ED50), ulcerogenic liabilities (UD50) and acute toxicity (ALD50). It was found to be almost comparable to phenylbutazone as regards anti-inflammatory activity was concerned but and minimum ulcerogenic liability and cardiovascular effects. Hence, it seems promising as an anti-inflammatory agent in our preliminary studies.

Chemical modification and chemical cross-linking for protein/enzyme stabilization

The protein function as well as its stability is governed by the amino acid sequence which in turn defines the collective noncovalent interactions leading to its specific conformation. Hence, it is not surprising that chemical modification with monofunctional and bifunctional reagents (the latter is called chemical cross-linking) causes structural changes (sometimes even subtle) which can result in significant changes in the stability. This review, while recapitulating the early lessons, analyses recent work (including work from authors' laboratory) involving these twin approaches for protein stabilization. In the case of chemical modification, both surface hydrophilization and enhancing surface hydrophobicity are reported to have enhanced protein stability in different cases. For cross-linking, the nature, span, and position of the cross-link are important factors in the stabilization achieved. It is also pointed out that in the case of aqueous-organic cosolvent mixtures, protein stability may depend upon the nature of the organic solvents. In the case of polyphenol oxidase and trypsin (at least), it is possible to choose "good" solvents on the basis of the Polarity index of the solvent.

Immobilization of Aspergillus niger xylanase on magnetic latex beads

Xylanase from Pectinex 3XL was purified 70-fold by precipitation with an enteric polymer, Eudragit S-100. The purified xylanase was immobilized on magnetic latex beads via carbodi-imide coupling. The immobilized preparation showed 80% of the total activity bound to the beads. The pH optimum remained unchanged at 6.0 and the Km increased from 0.25 g/100 ml (free enzyme) to 0.39 g/100 ml on immobilization. Immobilization resulted in significant thermal stability at 60 degrees C. The time course of hydrolysis of xylan at 60 degrees C by free enzyme as well as immobilized enzyme was also studied.

Purification and characterization of an acid phosphatase from Arachis hypogaea

An acid phosphatase from Arachis hypogaea (peanuts) has been purified. The electrophoretically homogeneous enzyme preparation is free of any phophodiesterase activity. The enzyme has a molecular weight of 120,000. Among the various phosphomonoesters tested, p-nitrophenylphosphate was found to be its most effective substrate. The Km for p-nitrophenylphosphate was 1.21 mM at pH 5.0 and 25 degrees C. The enzyme was thermostable and did not loose activity after 1 hr at 50 degrees C.

An insoluble aggregate of commercially available bovine serum albumin shows antiproteolytic activity

Chemical aggregation of bovine serum albumin by extensive chemical crosslinking with glutaraldehyde yielded an insoluble protein preparation with significant antiproteolytic activity. This was presumably due to the presence of alpha 2-macroglobulin in bovine serum albumin preparations. Chemical crosslinking of bovine serum albumin under optimum conditions was found to increase its antitryptic activity by about four times. The results indicate that enhanced rigidity of alpha 2-macroglobulin structure increases its antitryptic activity.