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1.
Nucleic Acids Res ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041433

RESUMO

Increasingly many studies reveal how ribosome composition can be tuned to optimally translate the transcriptome of individual cell types. In this study, we investigated the expression pattern, structure within the ribosome and effect on protein synthesis of the ribosomal protein paralog 39L (RPL39L). With a novel mass spectrometric approach we revealed the expression of RPL39L protein beyond mouse germ cells, in human pluripotent cells, cancer cell lines and tissue samples. We generated RPL39L knock-out mouse embryonic stem cell (mESC) lines and demonstrated that RPL39L impacts the dynamics of translation, to support the pluripotency and differentiation, spontaneous and along the germ cell lineage. Most differences in protein abundance between WT and RPL39L KO lines were explained by widespread autophagy. By CryoEM analysis of purified RPL39 and RPL39L-containing ribosomes we found that, unlike RPL39, RPL39L has two distinct conformations in the exposed segment of the nascent peptide exit tunnel, creating a distinct hydrophobic patch that has been predicted to support the efficient co-translational folding of alpha helices. Our study shows that ribosomal protein paralogs provide switchable modular components that can tune translation to the protein production needs of individual cell types.

2.
J Biol Chem ; 300(5): 107287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636658

RESUMO

Mycobacterial genomes encode multiple adenylyl cyclases and cAMP effector proteins, underscoring the diverse ways these bacteria utilize cAMP. We identified universal stress proteins, Rv1636 and MSMEG_3811 in Mycobacterium tuberculosis and Mycobacterium smegmatis, respectively, as abundantly expressed, novel cAMP-binding proteins. Rv1636 is secreted via the SecA2 secretion system in M. tuberculosis but is not directly responsible for the efflux of cAMP from the cell. In slow-growing mycobacteria, intrabacterial concentrations of Rv1636 were equivalent to the concentrations of cAMP present in the cell. In contrast, levels of intrabacterial MSMEG_3811 in M. smegmatis were lower than that of cAMP and therefore, overexpression of Rv1636 increased levels of "bound" cAMP. While msmeg_3811 could be readily deleted from the genome of M. smegmatis, we found that the rv1636 gene is essential for the viability of M. tuberculosis and is dependent on the cAMP-binding ability of Rv1636. Therefore, Rv1636 may function to regulate cAMP signaling by direct sequestration of the second messenger. This is the first evidence of a "sponge" for any second messenger in bacterial signaling that would allow mycobacterial cells to regulate the available intrabacterial "free" pool of cAMP.


Assuntos
Proteínas de Bactérias , AMP Cíclico , Mycobacterium tuberculosis , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , AMP Cíclico/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/genética , Viabilidade Microbiana , Mycobacterium smegmatis/metabolismo , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/genética , Ligação Proteica
3.
J Indian Assoc Pediatr Surg ; 29(3): 199-203, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38912018

RESUMO

Aim: This study aims to compare the efficacy and safety of topical application of common salt (CS) in comparison to silver nitrate (SN) for treating infants with umbilical granuloma (UG). Materials and Methods: We conducted an open-label, prospective, single-center, pilot randomized controlled trial. Thirty-seven infants with a clinical UG diagnosis were enrolled between October 2022 and July 2023, excluding those previously treated for UG. Patients were randomly assigned (using the Randomizer® app) to receive either topical CS (applied thrice daily by caregivers at home for 5 days) or SN (applied by pediatric surgeon in clinic and kept under occlusive dressing for 48 h). Patients with partial/no healing received an additional session of the same treatment. Nonresponders transitioned from CS to SN, and vice versa, for two more applications. Healing rates were compared with a significance level of α =0.05. Results: Out of 34 patients (18 CS and 16 SN), 32 successfully completed the trial (17 CS and 15 SN). No significant differences were observed in baseline characteristics. Efficacy rates of CS (19/22; 86.36%) and SN (11/17; 64.71%) did not significantly differ (P = 0.056; 95% confidence interval [CI] -0.4832-0.0502). No major adverse events were reported. CS showed superior healing outcomes in infants below 3 months of age (19/22; 86.36%) compared to SN (11/17; 64.71%) (P = 0.056; 95% CI - 0.4832-0.0502). The timing of umbilical cord detachment did not significantly affect healing rates. Conclusion: Widespread availability, ease of access, suitability for safe home application, and cost-effectiveness make CS a primary treatment option for UG. Larger patient cohorts are needed for conclusive results.

4.
J Indian Assoc Pediatr Surg ; 29(4): 370-375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39149444

RESUMO

Background and Aims: Of late, there are many legal representations from select quarters to halt all medical interventions in children with differences of sex development (DSD). In this survey on management decisions in DSD, we distil the views of Indian stakeholders: parents, physicians, and grown-up patients with DSD on their management decisions to identify decisional satisfaction or gender dysphoria. Methods: The survey domains included the patient demographics, final diagnosis, decision on the sex of rearing, surgical interventions, opinion of the stakeholders on the preferred age of sex assignment, final sex of rearing, and agreement/disagreement about sex assignment (gender dysphoria). Results: A total of 106 responses were recorded (66% parents, 34% grown-up patients aged 12-50 years). Among parents, 65/70 (95%) preferred the sex to be assigned soon after birth. All grown-up patients preferred sex to be assigned soon after birth. Regarding decisions on surgery, 74% of physicians and 75% of the grown-up patients felt parents should be allowed to decide interventions. Among Indian parents, 90% felt they should have the right to decide surgery in the best interest of their child for a safe social upbringing. Overall, gender dysphoria among Indian DSD patients was <1% (1/103, 0.97%). Conclusions: The predominant preference and opinion of major Indian stakeholders (physicians, parents, and grown-up DSD patients) support the existing approach toward DSD management, including early sex assignment and necessary medical intervention.

5.
ChemMedChem ; : e202400309, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136592

RESUMO

Stimuli activatable systems have the potential to deliver drugs to targeted areas by releasing therapeutic agents in response to diseased specific microenvironments such as the acidic environment commonly found in diseased tissues. This review article focuses on gossypol, a bioactive compound with inherent toxicity due to its formyl groups. It highlights the potential of imine-linked gossypol-based prodrugs and nanoparticle formulations for targeted delivery and controlled release. The unique presence of polyphenolic cores on gossypol can be utilized to prepare nanoparticles. This review offers valuable insights into designing safer and more effective drug delivery systems by elucidating the masking effect and stimuli-responsive release mechanisms. Numerous examples demonstrate the conversion of formyl groups to imines, creating prodrugs that mask reactive functionalities and offer pH-responsive release. This insight can guide the design of combination therapeutics, where a second drug with an amine terminal group can form imine-linked prodrugs. Additionally, the second part discusses the use of polyphenolic moieties to create stable nanoparticles from infinite polymeric networks. Through a comprehensive examination of gossypol's properties and applications, this review emphasizes the broader implications of such a masking strategy for optimizing the therapeutic benefits of many similar bioactive compounds while minimizing adverse effects.

6.
Indian J Psychiatry ; 66(2): 142-147, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523769

RESUMO

Background: Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder and is closely linked to stress. Psychiatric morbidities such as anxiety and depression are common in IBS. Long-term follow-up studies on anxiety and depressive symptoms in IBS and the impact of treatment are lacking in the Indian scenario. Aims: This study aimed to assess the various subtypes of IBS according to the Rome IV criteria, assess anxiety and depressive symptoms in patients with IBS at baseline and also at various phases of follow-up over one year, and see the impact of the treatment of both IBS and associated anxiety and depressive symptoms if present, in the severity of IBS and other psychiatric symptoms. Materials and Methods: Patients with IBS, aged between 18 and 65 years, were enrolled for the study. Subtypes and severity of IBS were assessed. Anxiety and depressive symptoms were assessed by the Hamilton Rating Scale for Anxiety (HAM-A) and the Hamilton Rating Scale for Depression (HAM-D), respectively. The patients were treated with conventional treatment of IBS with concomitant treatment of anxiety and depressive symptoms and were followed up for 1 year. Results: Thirty-seven patients completed a 1-year follow-up. The mean age was 38.4 ± 11.6 years. The majority were males (81%), and IBS-D (84%) was the most common subtype. Stressful life events (67.6%) and chronic stressors (64.9%) were present in the majority of the patients. The patients had moderate-to-severe anxiety at baseline (HAM-A score 27.8 ± 6.4) and moderate-to-severe depression at baseline (HAM-D score 19.7 ± 6.6). The improvement over 1 year was statistically significant (P = 0.000, two-tailed). A positive correlation between the severity score of IBS and HAM-D (r = 0.604) and HAM-A (r = 0.536) scores was present. Conclusion: There is a high prevalence of anxiety and depression in patients with IBS. With adequate treatment of both IBS and concomitant anxiety-depressive symptoms, there is a significant decrease in the severity of IBS, anxiety, and depression.

7.
EBioMedicine ; 99: 104915, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38113760

RESUMO

BACKGROUND: Degenerative cervical myelopathy (DCM) is the most common cause of adult spinal cord dysfunction globally. Associated neurological symptoms and signs have historically been explained by pathobiology within the cervical spine. However, recent advances in imaging have shed light on numerous brain changes in patients with DCM, and it is hypothesised that these changes contribute to DCM pathogenesis. The aetiology, significance, and distribution of these supraspinal changes is currently unknown. The objective was therefore to synthesise all current evidence on brain changes in DCM. METHODS: A systematic review was performed. Cross-sectional and longitudinal studies with magnetic resonance imaging on a cohort of patients with DCM were eligible. PRISMA guidelines were followed. MEDLINE and Embase were searched to 28th August 2023. Duplicate title/abstract screening, data extraction and risk of bias assessments were conducted. A qualitative synthesis of the literature is presented as per the Synthesis Without Meta-Analysis (SWiM) reporting guideline. The review was registered with PROSPERO (ID: CRD42022298538). FINDINGS: Of the 2014 studies that were screened, 47 studies were identified that used MRI to investigate brain changes in DCM. In total, 1500 patients with DCM were included in the synthesis, with a mean age of 53 years. Brain alterations on MRI were associated with DCM both before and after surgery, particularly within the sensorimotor network, visual network, default mode network, thalamus and cerebellum. Associations were commonly reported between brain MRI alterations and clinical measures, particularly the Japanese orthopaedic association (JOA) score. Risk of bias of included studies was low to moderate. INTERPRETATION: The rapidly expanding literature provides mounting evidence for brain changes in DCM. We have identified key structures and pathways that are altered, although there remains uncertainty regarding the directionality and clinical significance of these changes. Future studies with greater sample sizes, more detailed phenotyping and longer follow-up are now needed. FUNDING: ODM is supported by an Academic Clinical Fellowship at the University of Cambridge. BMD is supported by an NIHR Clinical Doctoral Fellowship at the University of Cambridge (NIHR300696). VFJN is supported by an NIHR Rosetrees Trust Advanced Fellowship (NIHR302544). This project was supported by an award from the Rosetrees Foundation with the Storygate Trust (A2844).


Assuntos
Doenças da Medula Espinal , Humanos , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos Transversais , Imageamento por Ressonância Magnética , Doenças da Medula Espinal/diagnóstico por imagem
8.
PLoS Negl Trop Dis ; 18(1): e0011831, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38166151

RESUMO

Yaws is an endemic disease caused by Treponema pallidum subsp. pertenue (TPE) that primarily affects children in rural regions of the tropics. The endemic character of yaws infections and the expected exclusive reservoir of TPE in humans opened a new opportunity to start a yaws eradication campaign. We have developed a multi-locus sequence typing (MLST) scheme for TPE isolates combining the previously published (TP0548, TP0488) and new (TP0858) chromosomal loci, and we compared this typing scheme to the two previously published MLST schemes. We applied this scheme to TPE-containing clinical isolates obtained during a mass drug administration study performed in the Namatanai District of Papua New Guinea between June 2018 and December 2019. Of 1081 samples collected, 302 (28.5%) tested positive for TPE DNA, from which 255 (84.4%) were fully typed. The TPE PCR-positivity in swab samples was higher in younger patients, patients with single ulcers, first ulcer episodes, and with ulcer duration less than six months. Non-treponemal serological test positivity correlated better with PCR positivity compared to treponema-specific serological tests. The MLST revealed a low level of genetic diversity among infecting TPE isolates, represented by just three distinct genotypes (JE11, SE22, and TE13). Two previously used typing schemes revealed similar typing resolutions. Two new alleles (one in TP0858 and one in TP0136) were shown to arise by intragenomic recombination/deletion events. Compared to samples genotyped as JE11, the minor genotypes (TE13 and SE22) were more frequently detected in samples from patients with two or more ulcers and patients with higher values of specific TP serological tests. Moreover, the A2058G mutation in the 23S rRNA genes of three JE11 isolates was found, resulting in azithromycin resistance.


Assuntos
Treponema pallidum , Bouba , Criança , Humanos , Treponema pallidum/genética , Úlcera , Tipagem de Sequências Multilocus , Bouba/epidemiologia , Papua Nova Guiné/epidemiologia , Treponema/genética , Mutação , Genótipo
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