Defining the clinical, molecular and imaging spectrum of adaptor protein complex 4-associated hereditary spastic paraplegia

Bi-allelic loss-of-function variants in genes that encode subunits of the adaptor protein complex 4 (AP-4) lead to prototypical yet poorly understood forms of childhood-onset and complex hereditary spastic paraplegia: SPG47 (AP4B1), SPG50 (AP4M1), SPG51 (AP4E1) and SPG52 (AP4S1). Here, we report a detailed cross-sectional analysis of clinical, imaging and molecular data of 156 patients from 101 families. Enrolled patients were of diverse ethnic backgrounds and covered a wide age range (1.0-49.3 years). While the mean age at symptom onset was 0.8 ± 0.6 years [standard deviation (SD), range 0.2-5.0], the mean age at diagnosis was 10.2 ± 8.5 years (SD, range 0.1-46.3). We define a set of core features: early-onset developmental delay with delayed motor milestones and significant speech delay (50% non-verbal); intellectual disability in the moderate to severe range; mild hypotonia in infancy followed by spastic diplegia (mean age: 8.4 ± 5.1 years, SD) and later tetraplegia (mean age: 16.1 ± 9.8 years, SD); postnatal microcephaly (83%); foot deformities (69%); and epilepsy (66%) that is intractable in a subset. At last follow-up, 36% ambulated with assistance (mean age: 8.9 ± 6.4 years, SD) and 54% were wheelchair-dependent (mean age: 13.4 ± 9.8 years, SD). Episodes of stereotypic laughing, possibly consistent with a pseudobulbar affect, were found in 56% of patients. Key features on neuroimaging include a thin corpus callosum (90%), ventriculomegaly (65%) often with colpocephaly, and periventricular white-matter signal abnormalities (68%). Iron deposition and polymicrogyria were found in a subset of patients. AP4B1-associated SPG47 and AP4M1-associated SPG50 accounted for the majority of cases. About two-thirds of patients were born to consanguineous parents, and 82% carried homozygous variants. Over 70 unique variants were present, the majority of which are frameshift or nonsense mutations. To track disease progression across the age spectrum, we defined the relationship between disease severity as measured by several rating scales and disease duration. We found that the presence of epilepsy, which manifested before the age of 3 years in the majority of patients, was associated with worse motor outcomes. Exploring genotype-phenotype correlations, we found that disease severity and major phenotypes were equally distributed among the four subtypes, establishing that SPG47, SPG50, SPG51 and SPG52 share a common phenotype, an 'AP-4 deficiency syndrome'. By delineating the core clinical, imaging, and molecular features of AP-4-associated hereditary spastic paraplegia across the age spectrum our results will facilitate early diagnosis, enable counselling and anticipatory guidance of affected families and help define endpoints for future interventional trials.

Snow cover area analysis and its relation with climate variability in Chandra basin, Western Himalaya, during 2001-2017 using MODIS and ERA5 data

Glaciers and snow cover area (SCA) plays an important role in river runoff in Himalayan region. There is a need to monitor SCA on spatio-temporal basis for better and efficient utilization of water resources. Moderate Resolution Imaging Spectroradiometer (MODIS) provides less cloudy data due to high temporal resolution as compared to other optical sensors for high elevation regions, and its 8-day snow cover product is globally used for snow cover estimation. The main objective of the present paper is to estimate annual and seasonal SCA in Chandra basin, Western Himalaya, and analysis of its variation with elevation, aspect, and slope during 2001 to 2017 using MODIS Terra (MOD10A2) and Aqua (MYD10A2) snow cover product as well as to correlate the same with temperature and precipitation using fifth generation European Centre for Medium-Range Weather Forecasts (ECMWF) Atmospheric Reanalysis of the global climate (ERA5) data. The total average SCA observed is 84.94% of basin area during the study period. The maximum annual average SCA was found as 91.23% in 2009 with minimum being 76.37% in 2016. Strong correlation is observed in annual and seasonal SCA with temperature which indicate that SCA variability is highly sensitive to temperature.

Response of Proliferative Lupus Nephritis with Pulse Cyclophosphamide Therapy during Induction Period: A Single Centre Study in Bangladesh

This prospective study was conducted to assess the response of proliferative lupus nephritis with pulse cyclophosphamide therapy during induction period in the department of Nephrology of Dhaka Medical College, Dhaka, Bangladesh from December 2012 to November 2013. A total of 35 clinically diagnosed SLE patients of class III/IV lupus nephritis were included. But 3 patients were dropped out during follow-up, therefore finally 32 patients (class III = 4, class IV = 28) were studied. The patients were evaluated for response on the basis of proteinuria, serum creatinine & active sediment in urine after 6th cycle of cyclophosphamide and 62.5% patients achieved complete response, 25% patients achieved partial response & 12.5% patients achieved no response. The factors favored complete response was early clinical presentation (7 months duration), proteinuria ≤3gm/day& normal renal function during their initial presentation. And higher anti ds DNA titre was an independent predictor for partial response/no response.

MP2: PATHOPHYSIOLOGY AND METABOLIC PHENOTYPE OF LOW BODY MASS INDEX DIABETES

Purpose of Study

Millions of individuals with low body mass index (BMI) globally have diabetes of unclear etiology. These include patients with Fibrocalculous Pancreatic Diabetes (FCPD) and Lean Diabetes (LD), defined by the presence or absence of pancreatic calcifications on ultrasound. We present the first studies using gold-standard methodologies to assess their metabolic phenotype.

Methods Used

Stepped euglycemic-hyperinsulinemic (∼30 and 80 mU/m2/min) clamp studies were performed in n=8 Indian males with LD (age 38±3 y, BMI 18.4±0.1 kg/m2, HbA1c 11.0±0.8%) and n=22 with FCPD (age 30±1 y, BMI 19.7±0.6 kg/m2, HbA1c 10.2±0.6%), compared with n=12 type 2 diabetes subjects (T2DM, BMI 25.7±0.3 kg/m2, HbA1c 9.7±0.6%) and n=12 age and BMI matched non-diabetic (ND) subjects and n=16 with type 1 diabetes (T1DM, HbA1c 9.1±0.3%). Therapeutic regimens were intensified for two weeks to correct glucose toxicity in all groups. Lean body mass was determined for all subjects from percentage of total body fat as assessed by DXA.

Summary of Results

Peripheral insulin sensitivity (Rd, mg/kg lean body weight/min), was markedly impaired in T2DM (2.3±0.6; p<0.01) compared to LD (9.2±1.6) and FCPD (5.8±0.7). Rd did not differ between T1DM (5.8±0.7), LD and FCPD groups (figure 1).

Conclusions

Thus, these comprehensive studies suggest patients with LD and FCPD are only mildly insulin resistant once hyperglycemia is corrected. This promotes a paradigm shift in our understanding of low body mass index diabetes and could have profound therapeutic implications for millions of people.

Abstract MP2 Figure 1

13: LOW BODY MASS INDEX DIABETES IS CHARACTERIZED BY IMPAIRED INSULIN SECRETION

Purpose of Study

Fibrocalculous Pancreatic Diabetes (FCPD) and Lean Diabetes (LD) are unique forms of diabetes affecting millions of people in developing countries, characterized by the presence or absence of pancreatic calcifications on ultrasound and insulin-requiring but ketosis-resistant diabetes. To optimize therapeutic strategies for FCPD and lean diabetes patients, it is imperative to conclusively assess their insulin secretion using gold-standard methodologies.

Methods Used

Comprehensive tests were undertaken in n=22 Indian males with FCPD (age 30±2 y, BMI 19.7±0.6 kg/m2, HbA1c 9.0±0.3%) and n=6 with LD (age 36±4 y, BMI 18.3±0.1 kg/m2, HbA1c 11.6±1.3%), and compared with n=12 age, BMI matched ND, n=16 T1D (HbA1c 9.1±0.3%) and n=12 T2D subjects (age 36±2 y, BMI 26.0±0.3 kg/m2, HbA1c 9.7±0.6%). Following correction of hyperglycemia for over two weeks, mixed-meal tolerance tests (MMTT) and C-peptide deconvolution analysis was performed to assess beta-cell function.

Summary of Results

Glucose and C-peptide responses to MMTT suggest subjects with FCPD (14.5±2.2 pmol/kg/min) and LD (15.0±2.9 pmol/kg/min) have markedly impaired insulin secretion relative to both ND and T2D (p<0.001), and not statistically different from T1D (figure 1).

Conclusions

Thus, we report the first studies showing that patients with low BMI diabetes have impaired insulin secretion despite correction of hyperglycemia, consistent with nutritional effects on beta cell development or function.

Abstract 13 Figure 1

Stereo-specific synthesis of analogs of nerve agents and their utilization for selection and characterization of paraoxonase (PON1) catalytic scavengers

Fluorogenic organophosphate inhibitors of acetylcholinesterase (AChE) homologous in structure to nerve agents provide useful probes for high throughput screening of mammalian paraoxonase (PON1) libraries generated by directed evolution of an engineered PON1 variant with wild-type like specificity (rePON1). Wt PON1 and rePON1 hydrolyze preferentially the less-toxic R(P) enantiomers of nerve agents and of their fluorogenic surrogates containing the fluorescent leaving group, 3-cyano-7-hydroxy-4-methylcoumarin (CHMC). To increase the sensitivity and reliability of the screening protocol so as to directly select rePON1 clones displaying stereo-preference towards the toxic S(P) enantiomer, and to determine accurately K(m) and k(cat) values for the individual isomers, two approaches were used to obtain the corresponding S(P) and R(P) isomers: (a) stereo-specific synthesis of the O-ethyl, O-n-propyl, and O-i-propyl analogs and (b) enzymic resolution of a racemic mixture of O-cyclohexyl methylphosphonylated CHMC. The configurational assignments of the S(P) and R(P) isomers, as well as their optical purity, were established by X-ray diffraction, reaction with sodium fluoride, hydrolysis by selected rePON1 variants, and inhibition of AChE. The S(P) configuration of the tested surrogates was established for the enantiomer with the more potent anti-AChE activity, with S(P)/R(P) inhibition ratios of 10-100, whereas the R(P) isomers of the O-ethyl and O-n-propyl were hydrolyzed by wt rePON1 about 600- and 70-fold faster, respectively, than the S(P) counterpart. Wt rePON1-induced R(P)/S(P) hydrolysis ratios for the O-cyclohexyl and O-i-propyl analogs are estimated to be >>1000. The various S(P) enantiomers of O-alkyl-methylphosphonyl esters of CHMC provide suitable ligands for screening rePON1 libraries, and can expedite identification of variants with enhanced catalytic proficiency towards the toxic nerve agents.

Municipal solid waste characteristics and management in Allahabad, India

Increasing population levels, rapid economic growth and rise in community living standard accelerates the generation rate of municipal solid waste (MSW) in Indian cities. Improper management of MSW causes hazards to inhabitants. The objectives of the study are to determine the quantitative and qualitative characteristics of MSW along with basic information and to create GIS maps for Allahabad city. The samples have been randomly collected from various locations and analyzed to determine the characteristics of MSW. A questionnaire survey has been carried out to collect data from inhabitants including MSW quantity, collection frequency, satisfaction level, etc. The Geographic Information System (GIS) has been used to analyze existing maps and data, to digitize the existing sanitary ward boundaries and to enter the data about the wards and disposal sites. The total quantity of MSW has been reported as 500 ton/day, and the average generation rate of MSW has been estimated at 0.39 kg/capita/day. The generated ArcGis maps give efficient information concerning static and dynamic parameters of the municipal solid waste management (MSWM) problem such as the generation rate of MSW in different wards, collection point locations, MSW transport means and their routes, and the number of disposal sites and their attributes.

WITHDRAWN: Municipal solid waste characteristics and management in Allahabad, India

The publisher regrets that this article was an accidental duplication of an article that has already been published in Waste Management, . The duplicate article has therefore been withdrawn.

Modelling of gaseous effluents by implementing Gaussian model under GIS environment

In the present work, Gaussian based air quality model has been implemented under GIS environment for the air quality emission data obtained from IFFCO power plant at Phulpur, Allahabad, India. The application of corrections for the non-point source, obstacles on ground, surface roughness and observation time has made the Gaussian based air pollution model more accurate and flexible for its use and in its adaptation for any other location. The Gaussian based air pollution model for the IFFCO plant, implemented under GIS environment, has been tested for various validation points to check its efficacy and has been found to be suitable for prediction of air pollutants in future. Further, a user interactive modelling interface has been developed using Visual Basic as a front-end, implementing the ArcObjects of the ArcGIS 8.3 to make it more user-friendly and increase its acceptability among environmentalists, planners and decision makers.

Germ-line msh6 mutations in colorectal cancer families

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is due primarily to inherited mutations in two mismatch repair genes, MSH2 and MLH1, whereas germ-line mutations in other mismatch repair genes are rare. We examined the frequency of germ-line msh6 mutations in a population-based series of 140 colorectal cancer patients, including 45 sporadic cases, 91 familial non-HNPCC cases, and 4 HNPCC cases. Among the 91 population-based familial non-HNPCC cases, germ-line msh6 mutations were found in 6 patients (7.1% of probands analyzed; median age at diagnosis, 61 years). These mutations included a splice site mutation, a frameshift mutation, two missense mutations that were demonstrated to be loss of function mutations, and two missense mutations for which functional studies were not possible. In contrast, germ-line msh6 mutations were not found in any of the 45 sporadic cases and the 4 HNPCC cases in the population-based series or in the second series of 58 clinic-based, primarily HNPCC families. Our data suggest that germ-line msh6 mutations predispose individuals to primarily late-onset, familial colorectal carcinomas that do not fulfill classic criteria for HNPCC.

The zinc finger gene Krox20 regulates HoxB2 (Hox2.8) during hindbrain segmentation

The zinc finger gene Krox20 and many Hox homeobox genes are expressed in segment-restricted domains in the hindbrain. The restricted expression patterns appear before morphological segmentation, suggesting that these transcription factors may play an early role in the establishment and identity of rhombomeric segments. In this paper, we show that the HoxB2 (Hox2.8) gene is normally upregulated in rhombomeres (r) 3, 4, and 5, and we identify an enhancer region upstream of the gene that imposes r3/r5 expression in transgenic mice. This enhancer contains three Krox20-binding sites required in vitro for complex formation with Krox20 protein and in vivo for rhombomere-restricted expression. In transgenic mice, Krox20 expressed in ectopic domains can transactivate a reporter construct containing the HoxB2 r3/r5 enhancer. These data demonstrate that Krox20 is a part of the upstream transcriptional cascade that directly regulates HoxB2 expression during hindbrain segmentation.

Electrocardiographic changes in tetanus: a serial study

Serial electrocardiograms (ECGs) were recorded in 20 consecutive male patients admitted to the Infectious Diseases Hospital, Calcutta with generalised tetanus. Age of patients varied from 5 to 40 years (mean age 20.4 years). Ten patients died. ECGs were recorded daily for the first week after admission and later every 2nd or 3rd day. Altogether, 167 ECGs were analysed. Sinus tachycardia was present in 17 (85%) patients, prolonged QT interval in 12 (60%) patients, non-specific ST-T abnormalities in 12 (60%) patients and P wave changes in 10 (50%) patients. Other abnormalities recorded, included short PR interval, supraventricular tachycardia, intraventricular conduction delay, sinus bradycardia, 1 degree A-V block, abnormal axis deviation, right ventricular hypertrophy and sino-atrial Wenckebach phenomenon, although all of the findings cannot clearly be attributed to tetanus. Spatial QRS-T angle was calculated in 18 of these patients to determine any possible change in this parameter of prognostic significance. Two out of 9 who survived had abnormally wide (greater than or equal to 55 degrees) spatial QRS-T angle on admission; the angle narrowed with recovery. In the non-survivor group, 4 patients had abnormally wide QRS-T angles on admission; further widening was noted in patients on whom follow-up tracings were available. The difference in spatial QRS-T angle between the survivor and the non-survivor groups was statistically significant (p less than 0.05). Spatial QRS-T angle changes have not been reported in tetanus before. Although non-specific, serial study in individual cases would be useful in assessing prognosis.

Influence of the dwarfing gene dw on egg production and viability under summer heat stress

1. Dwarf egg layer (Narmada XL) dwarf broiler (DB) and normal bodied sib (NB) hens were studied under cyclic summer hot and dry heat stress of 21.1 to 45.5 degrees C for a period of 50 d. The genotype effect for egg production was significant (P less than 0.01). 2. N-XL and DB genotypes laid 12.1% more eggs than NB. Egg production declined by 3.17, 1.27 and 3.25% for a rise in temperature (maximum) of 1 degree C for N-XL, DB and NB genotypes respectively. 3. Egg production in Narmada XL declined by 42% compared to 25% in the dwarf broilers. The regression coefficients differed significantly. 4. For polygenically identical DB and NB broiler breeder hens the heat stressor significantly reduced egg production 1.98% more in the NB genotype compared with DB with a 1 degree C rise in temperature. 5. Mortality was less in the N-XL as compared to DB, but NB hens showed 11.7% more mortality than dwarfs.

Direct oxidimetric determination of thiocarbonate sulphur with ferricyanide, using iron(II)-dimethylglyoxime or sodium nitroprusside as indicator

Direct determination of 15-50 mg of thiocarbonate sulphur can be achieved by a one-step titration with potassium ferricyanide, using iron(II)-dimethylglyoxime or sodium nitroprusside as indicator. Only one sulphur atom of the thiocarbonate ion undergoes oxidation to elemental sulphur, the other two separating as carbon disulphide.

Effect of dietary protein composition on placental protein, nucleic acid, free alpha amino N and enzymes in rats

Pregnant rats were fed six different diets from the first to the 15th, 17th or 19th day of pregnancy. Diets 1 to 5 contained the same amount of nitrogen (10% casein and unsupplemented or supplemented wheat or Bengalgram diets). Diet 6 contained 20% casein. Total placental protein, RNA, free alpha amino N contents and the activities of the enzymes arginase (EC 3.5.3.1), tyrosine amino transferase (TAT, EC 2.6.1.5) and lactate dehydrogenase (LDH, EC 1.1.1.27) were estimated. The fetal weight and placental weight, total placental protein, RNA and free alpha amino N and the activities of the enzymes increased with the gestational age, but the DNA content became constant after day 17 of gestation. The placental weight, protein, free alpha amino N and RNA contents were significantly reduced on wheat and Bengalgram diets as compared to 10% casein (control) diet. The low activities of arginase, TAT and LDH on these diets indicated impaired protein synthesis, as a result of reduction in the amino acid pool size. The fortification of wheat with lysine and Bengalgram with cystine, methionine and tryptophan showed significant improvement in the fetal weight and placental parameters. The values on the 20% casein diet were significantly higher than those observed on the 10% casein diet.

Familial occurrence of sinus bradycardia, short PR interval, intraventricular conduction defects, recurrent supraventricular tachycardia, and cardiomegaly

Four members of a family presenting with sinus bradycardia, a short P-R interval, intraventricular conduction defects, recurrent supraventricular tachycardia (SVT), syncope, and cardiomegaly had His bundle studies and were found to have markedly shortened A-H intervals (30 to 55 msec.) with normal H-V times (35 to 50 msec.). Right atrial pacing at rates as high as 170 to 215 per minute failed to increase the A-H or H-V intervals significantly. The data are compatible with the presence of an A-V nodal bypass tract (James bundle) or even complete absence of an A-V node. Ventricular pacing and spontaneous ventricular premature beats resulted in a short ventriculoatrial conduction time (110 msec.) suggesting that if A-V nodal bypass tracts exist, they are utilized in an antegrade and retrograde fashion. None of the features of WPW syndrome was present. The mechanism of syncope in the mother and daughter was intermittent third-degree heart block. Both went on to develop permanent complete heart block despite electrophysiologic studies demonstrating 1:1 A-V conduction at extremely rapid atrial pacing rates and both required implantation of permanent pacemakers. The mechanism of syncope in the two brothers was possibly marked sinus bradycardia, but transient complete heart block has not been ruled out. Permanent pacemaker therapy was recommended for both. The nature of the cardiomegaly, which was mild in three patients, is not known. Although not well documented, several maternal relatives have had enlarged hearts, SVT, complete heart block, and syncope.

Determination and comparison of the stability constants of some metal complexes of 8-hydroxyquinoline N-oxide and 8-hydroxyquinoline

The stability constants of 8-hydroxyquinoline N-oxide (or "oxine N-oxide") complexes with MnII, Fell, CoII, Kill, CuII, ZnII, CdII, UO211, AlIII, FeIII, YIII, LaIII, CeIII, PrIII, NdIII, SmIII, GdIII, DyIII, HoIII, ErIII, TmIII, YbIII, and LuIII, and oxine complexes with LnIII and YIII have been determined using pH-metric titrations in 50% v/v aqueous dioxan in the presence of 0.30M sodium perchlorate as the constant ionic medium. With both the ligands, the "gadolinium break" is observed in the case of the lanthanon complexes, whereas the bivalent ion complexes follow the Irving-Williams order of stability constants in the case of the oxine complexes. The stability constants of the oxine complexes have been found to be larger than those of the N-oxide complexes, though the oxine anion is only five times as basic as the N-oxide anion. A possible explanation for the increased stability of the oxine complexes in comparison with the corresponding N-oxide derivative is proposed.