Biomedical SERS - the current state and future trends.

Surface enhanced Raman spectroscopy (SERS) is meeting the requirements in biomedical science being a highly sensitive and specific analytical tool. By employing portable Raman systems in combination with customized sample pre-treatment, point-of-care-testing (POCT) becomes feasible. Powerful SERS-active sensing surfaces with high stability and modification layers if required are available for testing and application in complex biological matrices such as body fluids, cells or tissues. This review summarizes the current state in sample collection and pretreatment in SERS detection protocols, SERS detection schemes, i.e. direct and indirect SERS as well as targeted and non-targeted SERS, and SERS-active sensing surfaces. Moreover, the recent developments and advances of SERS in biomedical application scenarios, such as infectious diseases, cancer diagnostics and therapeutic drug monitoring is given, which enables the readers to identify the sample collection and preparation protocols, SERS substrates and detection strategies that are best-suited for their specific applications in biomedicine.

Diagnosis of 22q11.2 deletion syndrome in children with congenital heart diseases and facial dysmorphisms.

Background: Congenital heart diseases (CHDs) are the leading cause of birth defects. Approximately, 30% of CHDs are related to genetic syndromes accompanied by extracardiac anomalies. Aneuploidies and 22q11.2 deletions account for majority of cases. 22q11.2 deletion involves deletion of 30-40 genes, and varying deletions in this region lead to different phenotypes. Fluorescent in situ hybridization probes span a narrow region on chromosome 22 as compared to other recent techniques like multiplex ligation probe amplification assay (MLPA) which may also identify any gene duplications if present. Methods: Present study was a cross-sectional descriptive study. In total, 350 children with CHD reported to pediatric cardiology clinic during the study period. Of these, 60 children had associated facial dysmorphism. Out of these 60 children, 18 children had clinical phenotype characteristic of Down syndrome and hence these children were excluded from the study. Forty-two children with CHDs (conotruncal and other defects) and craniofacial features (subtle or obvious) suggestive of 22q11.2 deletion spectrum disorder were included in this study. Results: Nineteen percent of children presenting with CHDs and facial dysmorphisms had 22q11.2 deletion syndrome. All the samples were subjected to karyotyping. Conclusion: Metaphase FISH has been the method of choice for microdeletions. However, apart from technical challenges and longer turnaround time, FISH probes span a very narrow region in 22q11.2 chromosome (LCR22 D) and provide information about DiGeorge syndrome (DGS) only. Take home message is that patients of CHDs with facial dysmorphism should be investigated in an approach-based manner.

Correlation of renal length with anthropometric and demographic data in healthy children: A prospective cross sectional study.

Background: Renal size is an important parameter in the assessment of a child with renal disease. Renal size can be estimated by measuring renal length, renal volume, and cortical volume or thickness. Renal length depends on different factors, which include size, body mass index and gender. Ultrasonography is useful, non-invasive and easily available method for reliably performing the measurement of kidney length. This study was conducted to find out correlation between renal length and age and anthropometric variables in healthy children. This prospective cross sectional study was carried out with the following objectives: (a) To determine the anthropometric variable that correlated best with renal length in healthy children. (b) To develop a nomogram for renal length in healthy children. Methods: Five hundred healthy children were included in this study. Sonographic assessment of renal length was performed using real time mechanical sector scanner with 5 MHz and 8 MHz frequency. The renal length was correlated with somatic parameters like age, weight, height, body surface area and body mass index. Regression equations were derived for each pair of dependent and independent variables. Results: We performed the measurement of renal length in 500 healthy children. In our series, renal measuring parameters showed a good correlation with studied body parameters, height having the best correlation. Data from left and right kidneys are shown separately since there was small but statistically significant difference between them. Based on our study, using the height of the child, renal length may be calculated by using following equation: Left renal length (cm) = 0.052 × height (cm) + 1.042, Right renal length (cm) = 0.052 × height (cm) + 0.867. Conclusions: This study provides values of renal length (mean ± 2SD) in normal Indian children and its correlation with body parameters. Renal length may be easily calculated by derived linear regression equation. Nomograms of renal length with respect to age and height have been formulated. Renal Length was found to correlate best with height of the child.

Meckel Gruber and Joubert Syndrome Diagnosed Prenatally: Allelism between the Two Ciliopathies, Complexities of Mutation Types and Digenic Inheritance.

Background: Antenatally detected occipital encephalocele and polycystic kidneys are a common presentation of ciliopathies like Joubert syndrome and Meckel Gruber syndrome which have considerable genetic and phenotypic overlap. Case reports: We describe 3 cases of antenatally diagnosed occipital encephalocele and enlarged kidneys with fetal autopsy, histopathology & exome sequencing results. A novel nonsense variant in the CEP290 gene was reported in first case (Meckel syndrome). The second case shows the importance of fetal exome where the parents were carriers for 2 ciliopathy genes (TMEM138 & SDCCAG8). Diagnosis in this case was confirmed by fetal exome sequencing (Joubert syndrome). Multiexon deletion in TMEM67 and KIF14 present in trans was identified in the third case (Meckel syndrome), likely resulting in digenic inheritance. Conclusion: We report 2 cases of Meckel syndrome with a novel variant and multiexon deletion, and 1 case of Joubert syndrome which depicts the limitations of preconceptional carrier screening in ciliopathies due to overlapping phenotypes.

Hypomagnesemia with Secondary Hypoparathyroidism and Hypocalcemia due to Novel Variants in the Transient Receptor Potential Cation Channel Subfamily M Member 6 ( TRPM6 ) Gene.

HOMG1 (hypomagnesemia 1, intestinal) or hypomagnesemia with secondary hypocalcemia is a rare autosomal recessive disorder of magnesium metabolism, characterized by impaired magnesium absorption. This disorder may mimic other conditions presenting with neonatal seizures. Here, we report an infant diagnosed to have hypomagnesemia with secondary hypocalcemia due to novel variants in TRPM6 gene.

Monogenic lupus with neuroregression in an infant due to rare compound heterozygous variants in C1QA gene: Case based review.

BACKGROUND: Monogenic lupus is a rare variant of systemic lupus erythematosus (SLE) that develops in patients with a single gene disorder. Early complement component deficiencies were the first forms of monogenic lupus to be described and C1Q gene mutations are one of the most common forms. C1QA complement deficiency has been reported to occur usually due to biallelic variants in C1QA gene and compound heterozygous variants in C1QA gene have rarely been reported. Majority of the monogenic lupus patients with C1Q deficiency present with mucocutaneous, renal, and musculoskeletal manifestations. Our patient is an unusual case of monogenic lupus with severe neurological manifestations along with cutaneous, haematological, and hepatic manifestations secondary to rare compound heterozygous variants in C1QA gene and anti-ribosomal P autoantibody positivity. She was treated with glucocorticoids, rituximab and fresh frozen plasma with partial neurological recovery. Thus, we present a unique case of monogenic lupus due to a rare compound heterozygous variant in C1QA gene with a brief review of literature.

Novel combination of FLNC (c.5707G>A; p. Glu1903Lys) and BAG3 (c.610G>A; p.Gly204Arg) genetic variant expressing restrictive cardiomyopathy phenotype in an adolescent girl.

Pediatric restrictive cardiomyopathy (RCM) is the rarest in its group and accounts for only 2.5-5% of all the diagnosed cardiomyopathies in children. It is a relentless disease with poor prognosis, and heart transplantation is the only long-term treatment option. The aetiology of pediatric RCM varies and includes conditions such as endomyocardial fibrosis, storage disorder (Fabry's disease, MPS), drugs, radiation, post-cardiac transplantation and genetic. Genetic causes encompasses mutations in sarcomeric (troponin I and T, actin, myosin and titin) and nonsarcomeric protein-coding genes (Desmin, RSK2, lamin A/C and bcl-2-associated athanogene 3 (BAG3)). Inheritance of RCM could be autosomal dominant, autosomal recessive and X-linked. Here, we report a case of RCM in an adolescent girl, who was symptomatic with palpitations and breathlessness on exertion. The patient showed presence of rare variants in FLNC (c.5707G>A; p.Glu1903Lys) and BAG3 genes (c.610G>A; p.Gly204Arg). These two variants were detected individually in asymptomatic father and mother, respectively. FLNC gene codes for gamma filamin. These filamin proteins play important role in maintaining the structural integrity of the sarcomere. BAG3 is the main component of the chaperone-assisted selective autophagy (CASA) pathway. Mutant FLNC leads to the formation of protein aggregates which are cleared by an active protein quality control system including CASA pathway. For further verification, in silico protein-protein interaction was performed using online software and tools. The results showed evident interaction between FLNC and BAG3 with significant binding score (-826.6) between them.

Partial Trisomy 16q21-q24.3 with Novel Cardiac Manifestation of Left Ventricular Noncompaction Cardiomyopathy: A Case Report.

Partial trisomy 16q is most often a consequence of malsegregation from a balanced parental translocation involving chromosome 16q. It is characterized by nonspecific craniofacial dysmorphic features, hypotonia, developmental delay, psychomotor retardation, and systemic manifestations of cardiac defect, renal abnormalities, and lung abnormalities. The survival of these patients depends upon the extent and severity of the organs involved. The present literature was replete with cases of partial trisomy 16q having structural cardiac defects. However, in the present report we described a novel finding of myocardial disease in the form of left ventricular noncompaction (LVNC) cardiomyopathy associated with this genetic condition.

Type B lactic acidosis due to Warburg effect in a child presenting with T cell acute lymphoblastic leukaemia: a milder phenotype.

Lactic acidosis (LA) is characterised by persistently increased blood lactate >5 mmol/L. Type A LA due to anaerobic glycolysis is frequently seen during management of haematological malignancies. A rare form of LA known as type B LA, which occurs as a result of metabolic dysregulation at cellular level has been described recently. This has been reported to be because of Warburg effect (WE) or aerobic glycolysis, which is seen in cancerous cells as they rely on aerobic glycolysis rather than oxidative phosphorylation for energy generation. Presence of type B LA at initial presentation of haematological malignancies is a poor prognosticating factor and has rarely been reported in children. We present a child with T cell acute lymphoblastic leukaemia with mild phenotype of type B LA due to WE. She responded dramatically to definitive chemotherapy and tolerated intensive phase of chemotherapy without any significant morbidity.