APJ acts as a dual receptor in cardiac hypertrophy.

Cardiac hypertrophy is initiated as an adaptive response to sustained overload but progresses pathologically as heart failure ensues. Here we report that genetic loss of APJ, a G-protein-coupled receptor, confers resistance to chronic pressure overload by markedly reducing myocardial hypertrophy and heart failure. In contrast, mice lacking apelin (the endogenous APJ ligand) remain sensitive, suggesting an apelin-independent function of APJ. Freshly isolated APJ-null cardiomyocytes exhibit an attenuated response to stretch, indicating that APJ is a mechanosensor. Activation of APJ by stretch increases cardiomyocyte cell size and induces molecular markers of hypertrophy. Whereas apelin stimulates APJ to activate Gαi and elicits a protective response, stretch signals in an APJ-dependent, G-protein-independent fashion to induce hypertrophy. Stretch-mediated hypertrophy is prevented by knockdown of ß-arrestins or by pharmacological doses of apelin acting through Gαi. Taken together, our data indicate that APJ is a bifunctional receptor for both mechanical stretch and the endogenous peptide apelin. By sensing the balance between these stimuli, APJ occupies a pivotal point linking sustained overload to cardiomyocyte hypertrophy.

Coronary veins determine the pattern of sympathetic innervation in the developing heart.

Anatomical congruence of peripheral nerves and blood vessels is well recognized in a variety of tissues. Their physical proximity and similar branching patterns suggest that the development of these networks might be a coordinated process. Here we show that large diameter coronary veins serve as an intermediate template for distal sympathetic axon extension in the subepicardial layer of the dorsal ventricular wall of the developing mouse heart. Vascular smooth muscle cells (VSMCs) associate with large diameter veins during angiogenesis. In vivo and in vitro experiments demonstrate that these cells mediate extension of sympathetic axons via nerve growth factor (NGF). This association enables topological targeting of axons to final targets such as large diameter coronary arteries in the deeper myocardial layer. As axons extend along veins, arterial VSMCs begin to secrete NGF, which allows axons to reach target cells. We propose a sequential mechanism in which initial axon extension in the subepicardium is governed by transient NGF expression by VSMCs as they are recruited to coronary veins; subsequently, VSMCs in the myocardium begin to express NGF as they are recruited by remodeling arteries, attracting axons toward their final targets. The proposed mechanism underlies a distinct, stereotypical pattern of autonomic innervation that is adapted to the complex tissue structure and physiology of the heart.

Clinicopathological Profile of Appendicular Disease in Children: A Tertiary Health Care Center Study.

Background Acute appendicitis (AA) is the most common surgical emergency worldwide. Delay in diagnosis of disease often leads to serious complications such as perforation appendicitis (PA) and gangrenous appendicitis (GA). Aims and objectives The purpose of the study is to document clinicopathological outcomes in pediatric age group patients in a tertiary health care center. Material and method This study was a prospective observation study of 50 patients with pediatric appendicitis who had undergone emergency appendectomy from January 2022 to December 2022. All pediatric patients below 15 years of age with a diagnosis of AA were included. Institute ethical permission was granted before the study, and parent consent was taken for the surgery and also for inclusion in the study. After proper resuscitation, all patients underwent appendectomy, and necessary specimens were sent for histological examination. Based on histopathology reports, all patients were classified into four groups: AA, PA, GA, and normal appendix (NA). Results Out of 50 patients, 33 (66%) patients were males and 17 (34%) patients were females. The mean age of the patients was 10.22 ± 2.73 years. The mean age of AA, PA, GA, and NA patients were 10.25 ± 2.6 years, 9.78 ± 2.99 years, 10.00 ± 4.6 years, and 12.00 ± 2.8 years, respectively. The mean duration of symptoms at the time of hospital admission was 2.42 ± 0.97 days for histopathologically proven AA patients, 4.67 ± 2.1 days for GA patients, 2.8 ± 0.83 for PA patients, and one day for NA patients. Overall clinical presentation was right iliac fossa (RIF) pain in 36 (72%) patients, migration of pain in 31 (62%) patients, anorexia in 37 (74%) patients, nausea and vomiting in 43 (86%) patients fever in 26 (52%) patients, RIF tenderness in 50 (100%) patients, rebound tenderness in 39 (78%) patients, guarding in 19 (38%) patients, Psoas's sign in nine (18% patients), and Rovsing's sign in 19 (38%) patients. On histopathological examination of the sent specimen, AA was found in 36 (72%) patients, PA was found in nine (18%) patients, GA was found in three (6%) patients, and NA was found in two (4%) patients. Wound infection was the most common complication and was found in five (10%) patients. The average duration of hospital stay for AA, PA, GA, and NA was 4.33 ± 1.04 days, 9.56 ± 4.2 days, 12.33 ± 8.5 days, and 3.50 ± 0.71 days, respectively. Conclusion The appendicular disease is common in teenage male children. Fever, dehydration, and rebound tenderness at the RIF are clinically significant findings. Duration of symptoms at the time of diagnosis, post-appendectomy complication, and duration of hospital stay significantly correlated with histopathological findings.

Murine dishevelled 3 functions in redundant pathways with dishevelled 1 and 2 in normal cardiac outflow tract, cochlea, and neural tube development.

Dishevelled (Dvl) proteins are important signaling components of both the canonical beta-catenin/Wnt pathway, which controls cell proliferation and patterning, and the planar cell polarity (PCP) pathway, which coordinates cell polarity within a sheet of cells and also directs convergent extension cell (CE) movements that produce narrowing and elongation of the tissue. Three mammalian Dvl genes have been identified and the developmental roles of Dvl1 and Dvl2 were previously determined. Here, we identify the functions of Dvl3 in development and provide evidence of functional redundancy among the three murine Dvls. Dvl3(-/-) mice died perinatally with cardiac outflow tract abnormalities, including double outlet right ventricle and persistent truncus arteriosis. These mutants also displayed a misorientated stereocilia in the organ of Corti, a phenotype that was enhanced with the additional loss of a single allele of the PCP component Vangl2/Ltap (LtapLp/+). Although neurulation appeared normal in both Dvl3(-/-) and LtapLp/+ mutants, Dvl3(+/-);LtapLp/+ combined mutants displayed incomplete neural tube closure. Importantly, we show that many of the roles of Dvl3 are also shared by Dvl1 and Dvl2. More severe phenotypes were observed in Dvl3 mutants with the deficiency of another Dvl, and increasing Dvl dosage genetically with Dvl transgenes demonstrated the ability of Dvls to compensate for each other to enable normal development. Interestingly, global canonical Wnt signaling appeared largely unaffected in the double Dvl mutants, suggesting that low Dvl levels are sufficient for functional canonical Wnt signals. In summary, we demonstrate that Dvl3 is required for cardiac outflow tract development and describe its importance in the PCP pathway during neurulation and cochlea development. Finally, we establish several developmental processes in which the three Dvls are functionally redundant.

Surgical Management of Peptic Perforation in a Tertiary Care Center: A Retrospective Study.

BACKGROUND: The purpose of this study is to estimate disease burden, clinical features, and outcome in the emergency surgical management of peptic perforation in a rural government tertiary care center where patients are socioeconomically very poor and also impacted by lack of good quality health-care facility. MATERIALS AND METHODS: The study had retrospectively analyzed 121 patients with peptic perforation who had undergone emergency laparotomy at Midnapore medical college, West Bengal, India, from June 2018 to December 2019. All patients >12 years were included in this study. Exclusion criteria were other traumatic and nontraumatic gastrointestinal perforations. RESULTS: The study population had 112 males and 9 females with a mean age of 44.80 ± 15.29 years and maximum incidence in the 6th decade (P = 0.001). Smoking and alcohol were associated with 54.5% and 49.6%, respectively. The symptoms were pain abdomen (100%) with vomiting (38.8%) and fever (33.9%). The signs of hypotension, peritonitis, distension, and pneumoperitoneum were observed in 34.7%, 64.5%, 39.7%, and 83.5%, respectively. Only 20.7% of patients were admitted within the first 24 h. The mean duration of symptoms was 2.3 days. Most perforations were located on the duodenum (74.4%) with duodenal to gastric perforation ratio 2.9:1. The mean size was 1.02 cm. Chest infection (19%) was the most common complication. The mortality rate was 9.1%. The mean length of hospital stay was 11.1 days. CONCLUSION: Peptic perforation remains a major disease burden in our environment predominantly due to late presentation, leading to high morbidity and mortality.

Hypertension from targeted ablation of chromogranin A can be rescued by the human ortholog.

The secretory prohormone chromogranin A (CHGA) is overexpressed in essential hypertension, a complex trait with genetic predisposition, while its catecholamine release-inhibitory fragment catestatin is diminished, and low catestatin predicts augmented adrenergic pressor responses. These findings from studies on humans suggest a mechanism whereby diminished catestatin might increase the risk for hypertension. We generated Chga and humanized mice through transgenic insertion of a human CHGA haplotype in order to probe CHGA and catestatin in vivo. Chga mice displayed extreme phenotypic changes, including: (a) decreased chromaffin granule size and number; (b) elevated BP; (c) loss of diurnal BP variation; (d) increased left ventricular mass and cavity dimensions; (e) decreased adrenal catecholamine, neuropeptide Y (Npy), and ATP contents; (f) increased catecholamine/ATP ratio in the chromaffin granule; and (g) increased plasma catecholamine and Npy levels. Rescue of elevated BP to normalcy was achieved by either exogenous catestatin replacement or humanization of Chga mice. Loss of the physiological "brake" catestatin in Chga mice coupled with dysregulation of transmitter storage and release may act in concert to alter autonomic control of the circulation in vivo, eventuating in hypertension.

Interactions between telomerase and primase physically link the telomere and chromosome replication machinery.

In the ciliate Euplotes crassus, millions of new telomeres are synthesized by telomerase and polymerase alpha-primase during macronuclear development in mated cells. Concomitant with de novo telomere formation, telomerase assembles into higher-order complexes of 550 kDa, 1,600 kDa, and 5 MDa. We show here that telomerase is physically associated with the lagging-strand replication machinery in these complexes. Antibodies against DNA primase precipitated telomerase activity from all three complexes from mated cells but not the 280-kDa telomerase complex from vegetatively growing cells. Moreover, when telomerase was affinity purified, primase copurified with enzyme from mated cells but not with the 280-kDa vegetative complex. Thus, the association of telomerase and primase is developmentally regulated. Intriguingly, PCNA (proliferating cell nuclear antigen) was also found in the 5-MDa complex from mated cells. We therefore speculate that this complex is a complete telomere synthesis machine, while the smaller complexes are assembly intermediates. The physical association of telomerase and primase explains the coordinate regulation of telomeric G- and C-strand synthesis and the efficiency of telomere addition in E. crassus.

Serum-free generation of multipotent mesoderm (Kdr+) progenitor cells in mouse embryonic stem cells for functional genomics screening.

This unit describes a robust protocol for producing multipotent Kdr-expressing mesoderm progenitor cells in serum-free conditions, and for functional genomics screening using these cells. Kdr-positive cells are able to differentiate into a wide array of mesodermal derivatives, including vascular endothelial cells, cardiomyocytes, hematopoietic progenitors, and smooth muscle cells. The efficient generation of such progenitor cells is of particular interest because it permits subsequent steps in cardiovascular development to be analyzed in detail, including deciphering the mechanisms that direct differentiation. In addition, the oligonucleotide transfection protocol used to functionally screen siRNA and miRNA libraries is a powerful tool to reveal networks of genes, signaling proteins, and miRNAs that control the diversification of cardiovascular lineages from multipotent progenitors. Technical limitations, troubleshooting, and potential applications of these methods are discussed.

In vitro renaturation of alkaline family G/11 xylanase via a folding intermediate: alpha-crystallin facilitates refolding in an ATP-independent manner.

In this study, alkaliphilic family G/11 xylanase from alkali-tolerant filamentous fungi Penicillium citrinum MTCC 6489 was used as a model system to gain insight into the molecular aspects of unfolding/refolding of alkaliphilic glycosyl hydrolase protein family. The intrinsic protein fluorescence suggested a putative intermediate state of protein in presence of 2 M guanidium hydrochloride (GdmCl) with an emission maximum of 353 nm. Here we studied the refolding of GdmCl-denatured alkaline xylanase in the presence and the absence of a multimeric chaperone protein alpha-crystallin to elucidate the molecular mechanism of intramolecular interactions of the alkaliphilic xylanase protein that dictates its extremophilic character. Our results, based on intrinsic tryptophan fluorescence and hydrophobic fluorophore 8-anilino-1- naphthalene sulfonate-binding studies, suggest that alpha-crystallin formed a complex with a putative molten globule-like intermediate in the refolding pathway of xylanase in an ATP-independent manner. A 2 M GdmCl is sufficient to denature alkaline xylanase completely. The hydrodynamic radius (R(H)) of a native alkaline xylanase is 4.0, which becomes 5.0 in the presence of 2 M GdmCl whereas in presence of the higher concentration of GdmCl R(H) value was shifted to 100, indicating the aggregation of denatured xylanase. The alpha-crystallin.xylanase complex exhibited the recovery of functional activity with the extent of approximately 43%. Addition of ATP to the complex did not show any significant effect on activity recovery of the denatured protein.

Epidcermolytic hyperkeratosis: a case report.

Epidermolytic hyperkeratosis is a rare autosomal dominant genodermatosis that presents at birth as generalised erythema, blisters and erosions. In subsequent periods, erythema and blistering improves but patients go on to develop hyperkeratosis scalingthat is especially prominent along joint flexures, neck, hands and feet. The disease is caused by mutations in either keratin 1 or 10. Treatment options include topical emollients containing glycerin, lactic acid, urea and alpha-hydroxy acid and topical and systemic retinoids. Here a rare case in a 23 years old male is reported with epidermolytic hyperkeratosis and treated successfully with mixture of topical emollients with retinoid and systemic isotretinoin.

Tri-filial presentation of familial tuberous sclerosis with renal tumors.

Tuberous sclerosis is a rare neuro-cutaneous syndrome with autosomal dominant penetrance. Only some organs are involved, e.g., skin (earthy skin thickenings, ash leaf patches), cerebral cortex (hamartomatous nodules) and kidneys, (angiolipoma, adenocarcinoma). These hamar-tomatous swellings resemble potatoes and hence, referred to as tubers. We herein report on three patients (all familial), father, son and granddaughter, with this rare involvement, from the eastern part of India. The father and son had involvement of only the skin (i.e. nose) and kidneys while the disease penetrated further in the subsequent filial generations with son and granddaughter having skin, brain and bilateral kidney involvement. This kind of tri-filial progression has not till date, been reported from this region, making it an interesting case presentation.