Clinical and radiological spectrum of acquired inflammatory demyelinating diseases of the central nervous system in a tertiary care center

Objectives

Demyelinating diseases of central nervous system (CNS) are a broad spectrum of conditions with autoimmune process against myelin. In a resource limited country like India, it is imperative to perform proper clinical evaluation, neuroimaging to differentiate among various categories of CNS demyelinating diseases to decide regarding further workup and treatment. The objective of our study was to determine clinical presentation, imaging findings, serology results, diagnosis, and treatment outcome of primary demyelinating disorders of CNS.

Materials and Methods

In this prospective study, a total of 44 patients were enrolled over a period of 1 year. After proper evaluation, patients were categorized into different groups applying newer diagnostic criteria. Patients were treated with steroids, appropriate immunomodulatory therapy, and outcomes were analyzed.

Results

The majority of cases were of neuromyelitis optica spectrum disorder (NMOSD) (45.5%) with an overall female-to-male ratio of 3.4:1 and mean age of presentation was 30.5 ± 11.15. Myelitis (52.3%) followed by optic neuritis (45.5%) was the most common initial presentation. The most common site of involvement on magnetic resonance imaging was the spinal cord (particularly the cervicodorsal cord). The majority showed good response to therapy (77.27%) and two patients did not survive.

Conclusion

Higher disability observed among seropositive NMOSD patients warrants aggressive treatment during the first attack itself. It is important to suspect myelin oligodendrocyte glycoprotein antibody disease in patients with preceding viral infection. A good outcome in the majority is likely due to the availability of serological assays and aggressive immunomodulatory therapy.

AMAN with Ophthalmoparesis: A Rare Presentation

Acute motor axonal neuropathy (AMAN) is a variant of Guillain-Barré syndrome (GBS), characterized by acute areflexic flaccid quadriparesis with motor axonal changes and absence of demyelinating findings in electrophysiological studies. A 30-year-old man presented with acute onset flaccid type of weakness involving all four limbs, along with drooping of eyelids. Examination revealed ptosis with restricted horizontal and vertical eye movements. Spinomotor system examination revealed acute flaccid areflexic quadriparesis. Nerve conduction studies (NCS) showed features suggestive of motor axonal neuropathy changes. Cerebrospinal fluid (CSF) revealed albuminocytological dissociation. The diagnosis of AMAN was made, and the patient was treated with intravenous immunoglobulin (IVIg). His weakness gradually improved over 1 month, with partial improvement in ptosis and eye movements. This case highlights the occurrence of ophthalmoparesis in the AMAN variant of GBS. The presence of ophthalmoparesis and areflexia makes it necessary to exclude Miller-Fisher syndrome. But, the presence of axonal changes in nerve conduction study and the profound weakness with negative serum anti-GQ1b antibody profile, supports the diagnosis of AMAN. How to cite this article: Budumuru U, Muralidharan K, Sowmini PR, et al. AMAN with Ophthalmoparesis: A Rare Presentation. J Assoc Physicians India 2023;71(11):103-104.

Therapeutic Opportunities for Immunoreceptor-Engineered T Cell Therapy for Modulation of Alloimmunity

Achieving immunosuppression-free immune tolerance to an allograft is one of the central goals of transplantation. In this article, we review recent developments in the fields of T cell-based therapies and T cell engineering using chimeric Ag receptors and their potential for effective and targeted immune modulation of T and B cell activity in an effort to eliminate pre-existing alloantibodies (desensitization) and achieve long-term tolerance. Approaches that span preclinical to early clinical studies in transplantation will be reviewed, with specific emphasis on advances in T cell immunotherapy that have shown promise. Lastly, we conclude with a forward-looking discussion of how T cell-based therapies in other fields of medicine can be potentially applied to solid organ transplantation.

Considerations for addressing anti-vaccination campaigns: How did we get here and what can we do about it?

A course on vaccine development asked students to write a blog addressing general anti‐vaccination strategies and their significance today, in the context of the resistance seen against novel SARS‐CoV‐2 mRNA vaccines. This perspective explores how and why these efforts are successful at reducing vaccine uptake and why, for the most part, efforts to combat the movement have been unsuccessful. This summary of the collective view of the class provides recommendations for combatting current and future campaigns of misinformation. It is hoped that this perspective will serve as a call to action for clinical pharmacologists and translational scientists to do their part to educate the lay community and promote the science in an open and transparent manner to ensure that current and future vaccines fulfill their potential.

Germinal center responses to SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals

Vaccine-mediated immunity often relies on the generation of protective antibodies and memory B cells, which commonly stem from germinal center (GC) reactions. An in-depth comparison of the GC responses elicited by SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals has not yet been performed due to the challenge of directly probing human lymph nodes. Herein, through a fine-needle aspiration-based approach, we profiled the immune responses to SARS-CoV-2 mRNA vaccines in lymph nodes of healthy individuals and kidney transplant recipients (KTXs). We found that, unlike healthy subjects, KTXs presented deeply blunted SARS-CoV-2-specific GC B cell responses coupled with severely hindered T follicular helper cell, SARS-CoV-2 receptor binding domain-specific memory B cell, and neutralizing antibody responses. KTXs also displayed reduced SARS-CoV-2-specific CD4 and CD8 T cell frequencies. Broadly, these data indicate impaired GC-derived immunity in immunocompromised individuals and suggest a GC origin for certain humoral and memory B cell responses following mRNA vaccination.

Digital haemophilia: Insights into the use of social media for haemophilia care, research and advocacy

INTRODUCTION

The haemophilia community on Twitter is diverse, consisting of advocacy groups, patients, physicians, researchers and other users. However, the scope of this community is uncharacterized, and limited data is available regarding effective participation in this community.

AIM

To assess the types of users active in the haemophilia community on Twitter, as well as major themes present in haemophilia-related tweets.

METHODS

Forty-nine thousand five hundred and twelve tweets between September 2019 and September 2021 were classified using regular expressions. A subset of the classified tweets was manually analysed to identify prevalent discussion themes.

RESULTS

Among the top 250 users by post count, the largest categories of users were support and advocacy groups, people with bleeding disorders and healthcare providers. The largest thematic categories of tweets were gene therapy, contaminated haemophilia blood products, haemophilia research, clinical management of haemophilia and COVID-19. While misinformation was rare, negative and incorrect perceptions of haemophilia were present among the general public.

CONCLUSION

Our results demonstrate patterns of effective Twitter usage for patient care, research and advocacy purposes among the haemophilia community.

Utility of bilateral inferior petrosal sinus sampling for diagnosis and lateralization of Cushing's disease in the pediatric population: case series and review of the literature

OBJECTS

Cushing's disease (CD) is the most common cause of ACTH-dependent hypercortisolism in children age ≥ 7. The utility of bilateral inferior petrosal sinus sampling (BIPSS), an important test in adults, is less defined in children. We present a case series of children with ACTH-dependent hypercortisolemia and review the literature to assess the utility of BIPSS in the diagnosis and localization of CD.

METHODS

We performed an IRB-approved chart review of patients aged ≤ 18 with ACTH-dependent hypercortisolism at MGH between 2000 and 2019 and collected clinical, laboratory, radiographic, BIPSS, surgical, and outcomes data.

RESULTS

In our cohort (n = 21), BIPSS had a sensitivity of 93% and specificity of 100% for diagnosis of CD. Compared to surgery, successful BIPSS correctly predicted adenoma laterality in 69% of cases vs. 70% by MRI. Among patients with lesions ≥ 4 mm (n = 9), BIPSS correctly lateralized in 50% vs. 100% by MRI. In patients with subtle lesions (< 4 mm, n = 7), BIPSS correctly lateralized in 80% vs. 71% by MRI. In patients (n = 4) with CD and negative MRIs, BIPSS correctly lateralized in 75% cases. Surgical cure was achieved in 90% of patients and 95% of patients had long-term disease control.

CONCLUSIONS

In our cohort (n = 21; n = 20 CD, n = 1 ectopic ACTH secretion), BIPSS was sensitive and specific for the diagnosis of CD. Compared to MRI, BIPSS was not additionally helpful for lateralization in patients with lesions ≥ 4 mm on MRI. BIPSS was helpful in guiding surgical exploration and achieving immediate postoperative remission among patients with subtle and negative MRI findings.

The National Mental Health Survey of India (2016): Prevalence, socio-demographic correlates and treatment gap of mental morbidity

BACKGROUND

Recognizing the need for good quality, scientific and reliable information for strengthening mental health policies and programmes, the National Mental Health Survey (NMHS) of India was implemented by National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, in the year 2015-2016.

AIM

To estimate the prevalence, socio-demographic correlates and treatment gap of mental morbidity in a representative population of India.

METHODS

NMHS was conducted across 12 Indian states where trained field investigators completed 34,802 interviews using tablet-assisted personal interviews. Eligible study subjects (18+ years) in households were selected by a multi-stage, stratified, random cluster sampling technique. Mental morbidity was assessed using MINI 6. Three-tier data monitoring system was adopted for quality assurance. Weighted and specific prevalence estimates were derived (current and lifetime) for different mental disorders. Mental morbidity was defined as those disorders as per the International Statistical Classification of Diseases, Tenth Revision Diagnostic Criteria for Research (ICD-10 DCR). Multivariate logistic regression was conducted to examine risk for mental morbidity by different socio-demographic factors. Survey was approved by central and state-level institutional ethical committees.

RESULTS

The weighted lifetime prevalence of 'any mental morbidity' was estimated at 13.67% (95% confidence interval (CI) = 13.61, 13.73) and current prevalence was 10.56% (95% CI = 10.51, 10.61). Mental and behavioural problems due to psychoactive substance use (F10-F19; 22.44%), mood disorders (F30-F39; 5.61%) and neurotic and stress-related disorders (F40-F48; 3.70%) were the most commonly prevalent mental morbidity in India. The overall prevalence was estimated to be higher among males, middle-aged individuals, in urban-metros, among less educated and in households with lower income. Treatment gap for overall mental morbidity was 84.5%.

CONCLUSION

NMHS is the largest reported survey of mental morbidity in India. Survey estimated that nearly 150 million individuals suffer from one or the other mental morbidity in India. This information is to be used for planning, delivery and evaluating mental health programming in the country.

Distinct patterns of dentate gyrus cell activation distinguish physiologic from aberrant stimuli

Under physiologic conditions, the dentate gyrus (DG) exhibits exceptionally low levels of activity compared to other brain regions. A sparse activation pattern is observed even when the DG is engaged to process new information; for example, only ~1–3% of neurons in the DG granule cell layer (GCL) are activated after placing animals in a novel, enriched environment. Moreover, such physiologic stimulation of GCL neurons recruits young granule cells more readily than older cells. This sparse pattern of cell activation has largely been attributed to intrinsic circuit properties of the DG, such as reduced threshold for activation in younger cells, and increased inhibition onto older cells. Given these intrinsic properties, we asked whether such activation of young granule cells was unique to physiologic stimulation, or could be elicited by general pharmacological activation of the hippocampus. We found that administration of kainic acid (KA) at a low dose (5 mg/kg) to wildtype C57BL/6 mice activated a similarly sparse number of cells in the GCL as physiologic DG stimulation by exposure to a novel, enriched environment. However, unlike physiologic stimulation, 5 mg/kg KA activated primarily old granule cells as well as GABAergic interneurons. This finding indicates that intrinsic circuit properties of the DG alone may not be sufficient to support the engagement of young granule cells, and suggest that other factors such as the specificity of the pattern of inputs, may be involved.

A comparison of risperidone and olanzapine in the acute treatment of persistent delusional disorder: Data from a retrospective chart review

Introduction

There is a lack of pharmacological trials studying drug response in Persistent Delusional Disorder (PDD) to guide clinical practice. Available reviews of retrospective data indicate good response to second-generation antipsychotics, but even such data from India is sparse.

Objectives and aims

We aimed to compare the response of acute PDD to risperidone and olanzapine in our retrospective review.

Methods

We conducted a retrospective chart review of patients diagnosed with PDD (ICD-10) from 2000 to 2014 (n = 455) at our Center. We selected the data of patients prescribed either olanzapine or risperidone for the purpose of this analysis. We extracted data about dose, drug compliance and response, adverse effects, number of follow-up visits and hospitalizations. The study was approved by the Institute Ethics Committee.

Results

A total of 280/455 (61%) were prescribed risperidone and 86/455 (19%) olanzapine. The remaining (n = 89; 20%) had received other antipsychotics. The two groups were comparable in socio-demographic and clinical characteristics of PDD. Compliance was good and comparable in both groups (> 80%, P = 0.2). Response to treatment was comparable in both groups (85% partial response and > 52% good response, all P > 0.3). Olanzapine was effective at lower mean chlorpromazine equivalents than risperidone (240 vs. 391, P < 0.05).

Conclusion

Our study indicates a good response to both risperidone and olanzapine, if compliance to treatment can be ensured. In the absence of specific treatment guidelines for PDD, second-generation antipsychotics like risperidone and olanzapine offer good treatment options for this infrequently encountered and difficult to treat psychiatric disorder.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Childhood maltreatment and corpus callosum volume in recently diagnosed patients with bipolar I disorder: data from the Systematic Treatment Optimization Program for Early Mania (STOP-EM)

Childhood trauma (CT) has been associated with abnormalities in the corpus callosum (CC). Decreased CC volumes have been reported in children and adolescents with trauma as well as adults with CT compared to healthy controls. CC morphology is potentially susceptible to the effects of Bipolar Disorder (BD) itself. Therefore, we evaluated the relationship between CT and CC morphology in BD. We using magnetic resonance imaging in 53 adults with BD recently recovered from their first manic episode, with (n = 23) and without (n = 30) CT, defined using the Childhood Trauma Questionnaire (CTQ) and 16 healthy controls without trauma. ANCOVA was performed with age, gender and intracranial volume as covariates in order to evaluate group differences in CC volume. The total CC volume was found to be smaller in BD patients with trauma compared to BD patients without trauma (p < .05). The differences were more pronounced in the anterior region of the CC. There was a significant negative correlation between CTQ scores and total CC volume in BD patients with trauma (p = .01). We did not find significant differences in the CC volume of patients with/without trauma compared to the healthy subjects. Our sample consists of patients recovered from a first episode of mania and are early in the course of illness and reductions in CC volume may occur late in the course of BD. It might mean there may be two sources of CC volume reduction in these patients: the reduction due to trauma, and the further reduction due to the illness.

Phase-controlling phononic crystals: realization of acoustic Boolean logic gates

A phononic crystal (PC) consisting of a square array of cylindrical polyvinylchloride inclusions in air is used to construct a variety of acoustic logic gates. In a certain range of operating frequencies, the PC band structure shows square-like equi-frequency contours centered off the gamma point. This attribute allows for the realization of non-collinear wave and group velocity vectors in the PC wave vector space. This feature can be utilized to control with great precision, the relative phase between propagating acoustic waves in the PC. By altering the incidence angle of the impinging acoustic beams or varying the PC thickness, interferences occur between acoustic wave pairs. It is recognized that information can be encoded with this mechanism (e.g., wave amplitudes/interference patterns) and accordingly to construct a series of logic gates emulating Boolean functions. The NAND, XOR, and NOT gates are demonstrated with finite-difference time-domain simulations of acoustic waves impinging upon the PC.

Bifrontal ECT for drug-induced psychosis in Parkinson's disease

Psychosis has been documented to occur during treatment for idiopathic Parkinson's disease (PD). This case report describes an elderly male who developed psychosis during the course of treatment for idiopathic PD. He was treated with clozapine but experienced significant adverse effects without clinical improvement. He was prescribed bifrontal electroconvulsive therapy (BF-ECT). Here, we report the efficacy of BF-ECT in treating psychosis and motor symptoms in PD, without producing cognitive side effects in an elderly male.

Delayed onset, protracted delirium and aspiration pneumonitis associated with a combination of clozapine and electroconvulsive therapy

Few studies reported the efficacy and safety in combination of clozapine and electroconvulsive therapy (ECT) in schizophrenia; systematic studies are lacking. Side effects like seizure, and confusional state are reported. Authors report two cases of delayed onset/protracted delirium with ECT and clozapine in schizophrenia, one of whom developed aspiration pneumonitis possibly due to clozapine hyper-salivation. Delirium improved with stopping of ECT and clozapine. Clozapine monotherapy restarted to previous dosages in both cases without recurrence of delirium. Authors recommend for careful monitoring for delirium in ECT augmentation on high dose clozapine. Unilateral ECT may be preferred for augmenting clozapine.

Experimental and theoretical evidence for subwavelength imaging in phononic crystals

We show experimentally and theoretically that super resolution can be achieved while imaging with a flat lens consisting of a phononic crystal exhibiting negative refraction. This phenomenon is related to the coupling between the incident evanescent waves and a bound slab mode of the phononic crystal lens, leading to amplification of evanescent waves by the slab mode. Super resolution is only observed when the source is located very near to the lens, and is very sensitive to the location of the source parallel to the lens surface as well as to site disorder in the phononic crystal lattice.

High energy density materials from azido cyclophosphazenes

Azido substituted cyclophosphazenes were prepared and their standard heats of formation were calculated based on experimentally determined heats of combustion.

Preparation of the First Examples of Ansa−Spiro Substituted Fluorophosphazenes and Their Structural Studies: Analysis of C−H···F−P Weak Interactions in Substituted Fluorophosphazenes

The reactions of fluorophosphazenes, endo ansa FcCH(2)P(S)(CH(2)O)(2)[P(F)N](2)(F(2)PN) (1) (Fc = ferrocenyl) and spiro [RCH(2)P(S)(CH(2)O)(2)PN](F(2)PN)(2) (R = Fc (2), C(6)H(5) (3)], with dilithiated diols have been explored. The study resulted in the formation of the first examples of ansa-spiro substituted fluorinated cyclophosphazenes as well as a bisansa substituted fluorophosphazene. The bisansa compound [1,3-[FcCH(2)P(S)(CH(2)O)(2)]][1,5-[CH(2)(CH(2)O)(2)]]N(3)P(3)F(2) (4) was found to be nongeminaly substituted with both the ansa rings in cis configuration, which is in stark contrast to the observations on cyclic chlorophosphazenes where geminal bisansa formation has been observed. The ansa-spiro compounds (5-7) underwent the ansa to spiro transformation leading to dispiro compounds in the presence of catalytic amounts of CsF at room temperature. Two of the ansa-spiro compounds, endo-[3,5-[FcCH(2)P(S)(CH(2)O)(2)]][1,1-[CH(2)(CH(2)O)(2)]]N(3)P(3)F(2) (5) and endo-[3,5-[FcCH(2)P(S)(CH(2)O)(2)]][1,1-[FcCH(2)P(S)(CH(2)O)(2)]]N(3)P(3)F(2) (6), were structurally characterized, and the crystal structures indicate boat-chair conformation as well as crown conformation for the eight-membered ansa rings. Weak C-H.F-P interactions observed in the crystal structures of the ansa-spiro substituted fluorophosphazene derivatives have been analyzed and compared with C-H.F-P interactions of other fluorinated phosphazenes and thionyl phosphazenes.

Ansa versus spiro substitution of cyclophosphazenes: is fluorination essential for ansa to spiro transformation of cyclophosphazenes?

Fluorinated ansa substituted cyclophosphazenes endo-FcCH(2)P(S)(CH(2)O)(2)[P(F)N](2)(F(2)PN) [Fc = ferrocenyl] (1) and exo-FcCH(2)P(S)(CH(2)O)(2)[P(F)N](2)(F(2)PN) (2) readily transform to the spirocyclic compound [FcCH(2)P(S)(CH(2)O)(2)PN](F(2)PN)(2) (3) not only in the presence of CsF but also with non-fluorinated bases such as Cs(2)CO(3), K(2)CO(3), KOBu(t), Et(3)N, DABCO, DBN, and DBU. The analogous tetrachloro ansa compound exo-FcCH(2)P(S)(CH(2)O)(2)[P(Cl)N](2)(Cl(2)PN) (5), however, did not transform to the chlorinated spiro compound (6) in the presence of these bases. With excess of CsF, P-Cl bonds of 5 were found to undergo fluorination leading to the formation of 2, which transformed to spirocyclic compound 3. Time dependent (31)P NMR spectroscopy was used to monitor this transformation. Crystal structure studies on the ansa substituted compounds 4 and 5 have shown weak bonding interactions involving C-H...Cl, C-H...O, and C-H...S interactions.

Phylogeography of the asian elephant (Elephas maximus) based on mitochondrial DNA

Populations of the Asian elephant (Elephas maximus) have been reduced in size and become highly fragmented during the past 3,000 to 4,000 years. Historical records reveal elephant dispersal by humans via trade and war. How have these anthropogenic impacts affected genetic variation and structure of Asian elephant populations? We sequenced mitochondrial DNA (mtDNA) to assay genetic variation and phylogeography across much of the Asian elephant's range. Initially we compare cytochrome b sequences (cyt b) between nine Asian and five African elephants and use the fossil-based age of their separation (approximately 5 million years ago) to obtain a rate of about 0.013 (95% CI = 0.011-0.018) corrected sequence divergence per million years. We also assess variation in part of the mtDNA control region (CR) and adjacent tRNA genes in 57 Asian elephants from seven countries (Sri Lanka, India, Nepal, Myanmar, Thailand, Malaysia, and Indonesia). Asian elephants have typical levels of mtDNA variation, and coalescence analyses suggest their populations were growing in the late Pleistocene. Reconstructed phylogenies reveal two major clades (A and B) differing on average by HKY85/gamma-corrected distances of 0.020 for cyt b and 0.050 for the CR segment (corresponding to a coalescence time based on our cyt b rate of approximately 1.2 million years). Individuals of both major clades exist in all locations but Indonesia and Malaysia. Most elephants from Malaysia and all from Indonesia are in well-supported, basal clades within clade A. thus supporting their status as evolutionarily significant units (ESUs). The proportion of clade A individuals decreases to the north, which could result from retention and subsequent loss of ancient lineages in long-term stable populations or, perhaps more likely, via recent mixing of two expanding populations that were isolated in the mid-Pleistocene. The distribution of clade A individuals appears to have been impacted by human trade in elephants among Myanmar, Sri Lanka, and India, and the subspecies and ESU statuses of Sri Lankan elephants are not supported by molecular data.

Syntheses of novel exo and endo isomers of ansa-substituted fluorophosphazenes and their facile transformations into spiro isomers in the presence of fluoride ions

Reactions of the dilithiated diols RCH2P(S)(CH2OLi)2 [R = Fc (1), Ph (2) (Fc = ferrocenyl)] with N3P3F6 in equimolar ratios at -80 degrees C result exclusively in the formation of two structural isomers of ansa-substituted compounds, endo-RCH2P(S)(CH2O)2[P(F)N]2(F2PN) [R = Fc (3a), Ph (4a)] and exo-RCH2P(S)(CH2O)2[P(F)N]2(F2PN) [R = Fc (3b), Ph (4b)], which are separated by column chromatography. Increasing the reaction temperature to -40 degrees C results in more of the exo isomers 3b and 4b at the expense of the endo isomers. The formation of the ansa-substituted compounds is found to depend on the dilithiation of the diols, as a reaction of the silylated phosphine sulfide FcCH2P(S)(CH2OSiMe3)2 (5) with N3P3F6 in the presence of CsF does not yield either 3a or 3b but instead gives the spiro isomer [FcCH2P(S)(CH2O)2 PN](F2PN)2 (6) as the disubstitution product of N3P3F6. The ansa isomers 3a and 3b are transformed into the spiro compound 6 in the presence of catalytic amounts of CsF at room temperature in THF, while 4a and 4b are transformed into the spiro compound [PhCH2P(S)(CH2O)2PN](F2PN)2 (7) under similar conditions. The novel conversions of ansa-substituted phosphazenes into spirocyclic phosphazenes were monitored by time-dependent 31P NMR spectroscopy. The effect of temperature on a transformation was studied by carrying out reactions at various temperatures in the range from -60 to +33 degrees C for 3b. In addition, compounds 3a, 3b, 4a, and 6 were structurally characterized. In the case of the ansa compounds, the nitrogen atom flanked by the bridging phosphorus sites was found to deviate significantly from the plane defined by the five remaining atoms of the phosphazene ring.

Urine and plasma galactitol in patients with galactose-1-phosphate uridyltransferase deficiency galactosemia

Urinary excretion of galactitol was determined in 95 normals (N/N), 67 galactosemic (G/G), and 39 compound heterozygotes for the Duarte and galactosemia genotype (D/G). Galactitol excretion is age-dependent in both normal individuals and patients with classic galactosemia on lactose-restricted diets. In galactosemic patients who are homozygous for the Q188R mutation, urinary galactitol levels were fivefold to 10-fold higher than those of normal subjects of comparable age. All but a few patients with classic galactosemia with the Q188R mutation and another mutant G allele had urinary excretion comparable to the Q188R homozygous patients. African-American galactosemic patients with the S135L mutation of the galactose-1-phosphate uridyltransferase (GALT) gene also excreted abnormal quantities of galactitol. Most subjects with a Duarte allele and a G allele excrete normal amounts of the sugar alcohol. There is a correlation between galactitol excretion and red blood cell (RBC) galactose-1-phosphate (gal-1-P). Plasma galactitol was also elevated in galactosemic patients (3.4 to 23.2 micromol/L; undetectable in normal individuals). In contrast to the decrease in urinary galactitol with age, plasma levels remain in a narrow concentration range with no significant difference with age. Urine and plasma galactitol distinguish galactosemic patients from normals. In addition, urinary galactitol excretion may be an important parameter for the assessment of steady-state galactose metabolism in galactosemia.

Evidence that microdeletions in the alpha globin gene protect against the development of sickle cell glomerulopathy in humans

There is a large variability in the severity of the clinical manifestations of sickle cell anemia (SSA), including renal involvement. Haplotypes in the beta-globin gene cluster associated with the geographical origin of the sickle mutation, as well as microdeletions in the alpha-globin genes, could provide an epigenetic influence on the heterogeneous outcome in SSA. It has been determined that the cause of progressive renal insufficiency in SSA is a glomerulopathy, clinically detected by the presence of macroalbuminuria (albumin excretion rate >300 mg/g creatinine). To investigate the role of the alpha-globin gene microdeletion and beta-globin gene cluster haplotypes on the degree of glomerular involvement, 76 adult SSA patients (hemoglobin SS) were studied to determine the relationship between these genetic markers and the development of sickle cell glomerulopathy. Macroalbuminuria was present in 22 (29%) of 76 adult SSA patients. The coinheritance of microdeletions in one or two of the four alpha-globin genes (alpha-thalassemia) was associated with a lower prevalence of macroalbuminuria (13%) versus patients with intact alpha-globin genes (40%, P = 0.01). By contrast, there was no association between albuminuria and beta-globin gene haplotypes (Central African Republic [CAR] versus non-CAR haplotypes). Patients with alpha-globin gene microdeletions had lower mean corpuscular volumes and mean corpuscular hemoglobin concentration than patients with all four alpha genes (86+/-2 versus 99+/-3 fl, and 33.9+/-0.2 versus 34.9+/-0.2%, respectively, P<0.05). There were no such hematologic differences between CAR and non-CAR beta-globin haplotypes. There were no differences in duration of disease (age), hemoglobin levels, reticulocyte index, and lactate dehydrogenase levels between those with and without glomerulopathy, but the mean arterial pressure was higher (87+/-1 mm Hg) in patients with intact alpha gene locus versus those with microdeletions (80+/-2 mm Hg, P<0.05). It is concluded that the coinheritance of microdeletions in the alpha-globin gene locus in SSA patients confers "renoprotection" by mechanisms not related to the degree of anemia or the severity of hemolysis, but could be related to a reduced mean corpuscular volume or to a lower erythrocyte hemoglobin concentration.

Production of congenic mouse strains carrying NOD-derived diabetogenic genetic intervals: an approach for the genetic dissection of complex traits

Insulin-dependent (Type 1) diabetes (IDD) in the NOD mouse is inherited as a complex polygenic trait making the identification of susceptibility genes difficult. Currently none of the non-MHC IDD susceptibility genes in NOD have been identified. In this paper we describe the congenic mouse approach that we are using for the dissection of complex traits, such as IDD. We produced a series of six congenic strains carrying NOD-derived diabetogenic genomic intervals, which were previously identified by linkage analysis, on a resistant background. These congenic strains were produced for the purpose of characterizing the function of each of these genes, alone and in combinations, in IDD pathogenesis and to allow fine mapping of the NOD IDD susceptibility genes. Histological examination of pancreata from 6 to 8-month-old congenic mice reveals that intervals on Chromosomes (Chrs) 1 and 17, but not 3, 6, and 11, contain NOD-derived genes that can increase the trafficking of mononuclear cells into the pancreas. Insulitis was observed only very rarely, even in older congenic mice, indicating that multiple genes are required for this phenotype. These results demonstrate the utility of this congenic approach for the study of complex genetic traits.

Unique mosaicism of tetraploidy and trisomy 8: clinical, cytogenetic, and molecular findings in a live-born infant

We report on a live-born infant with mosaicism of tetraploidy and trisomy 8 who had craniofacial abnormalities, cardiac and genitourinary defects, agenesis of the corpus callosum, and anomalies of limbs. The infant died at age 14 weeks. Molecular studies were done on peripheral blood lymphocytes and cultured amniocytes to determine the origin of the cytogenetic abnormalities. On the basis of the results, we describe a possible mechanism to explain these abnormalities. To our knowledge, this infant represents the first reported case of mosaic trisomy 8 with a tetraploid cell line.

Asplenia syndrome in a child with a balanced reciprocal translocation of chromosomes 11 and 20 [46,XX,t(11;20)(q13.1;q13.13)]

We present a 6-year-old girl with a balanced 11;20 translocation [46,XX,t(11;20)(q13.1;q13.13)pat], asplenia, pulmonic stenosis, Hirschsprung disease, minor anomalies, and mental retardation. This case represents the second report of an individual with situs abnormalities and a balanced chromosome rearrangement involving a breakpoint at 11q13. Polymerase chain reaction (PCR) analysis of microsatellite markers excluded uniparental disomy for chromosomes 11 and 20. Segregation analysis of markers in the 11q13 region in the proposita and her phenotypically normal carrier sibs did not show a unique combination of maternal and paternal alleles in the patient. We discuss several possible explanations for the simultaneous occurrence of situs abnormalities and a balanced 11;20 translocation. These include (1) chance, (2) a further chromosome rearrangement in the patient, (3) gene disruption and random situs determination, and (4) gene disruption plus transmission of a recessive or imprinted allele from the mother.

Characterizations of candidate genes for IDD susceptibility from the diabetes-prone NOD mouse strain

The nucleotide sequences of the NOD and C57BL/6J alleles of Glut-2, Sod-2, and Il-2 were determined by RT-PCR sequencing. Each of these loci is located in intervals that strongly correlated with susceptibility to diabetes in an (NOD/Uf x C57BL/6J)F1 x NOD/Uf backcross. No significant variations in the alleles of Glut-2 at 16 cM on Chromosome (Chr) 3 or Sod-2 at 8 cM on Chr 17 were detected. However, the Il-2 allele in NOD at 20 cM on Chr 3 was found to differ from that in C57BL/6J by a complex mutation involving the contraction of a simple sequence repeat (SSR). Il-2 in NOD differs from the allele in C57BL/6J via a complex mutation involving a deletion of four CAG codons from the SSR together with a length-compensatory four-codon duplication of a segment 5' from the SSR. Two nonsynonymous mutations in the coding region 5' to the SSR were also detected. Only these two allelic forms of Il-2 were detected in a survey of 13 standard inbred lines and 4 wild mouse strains. We propose to designate these alleles as Il-2a (for alleles such as C57BL/6J that contain 12 CAG repeats) and Il-2b (for alleles such as NOD), which occurred in a variety of standard inbred strains and in all four wild Mus musculus domesticus tested. The distribution of these Il-2 alleles among inbred strains correlated with the detection of Chr 3 as an interval effecting diabetes susceptibility in three separate genetic crosses.(ABSTRACT TRUNCATED AT 250 WORDS)