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1.
Acta Vet Hung ; 72(2): 99-108, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38900580

RESUMO

Platelet-rich plasma (PRP) has emerged as a cornerstone in veterinary regenerative medicine. The present study evaluated the impact of the operator on the qualitative and quantitative features of non-activated PRP derived from canine whole blood. Blood was collected in anticoagulant acid citrate dextrose from twelve healthy adult dogs and PRP was prepared according to the double-spin method. Both operators followed an identical protocol and utilized the same equipment for PRP preparation from the pooled blood samples. The resulting PRP underwent characterization, classification and coding based on minimum reporting standards. The consistency and internal reliability of different parameters were also assessed using the intraclass correlation coefficient and Cronbach's alpha values. Variables such as white blood cell (WBC) concentration, relative WBC composition and mean platelet volume (MPV) showed poor reliability, and WBC concentration and MPV also had unacceptable internal consistency. Significant differences were observed in several qualitative and quantitative parameters of the prepared PRP, highlighting the influence of the operator even when the same protocol and equipment were used. Our study has direct implications to regenerative medicine, reinforcing the urgency to set minimum requirements for reporting PRP in research studies.


Assuntos
Plasma Rico em Plaquetas , Animais , Cães/sangue , Masculino , Feminino
2.
Cell Tissue Bank ; 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542003

RESUMO

Biomaterials capable of managing wounds should have essential features like providing a natural microenvironment for wound healing and as support material for stimulating tissue growth. Eggshell membrane (ESM) is a highly produced global waste due to increased egg consumption. The unique and fascinating properties of ESM allow their potential application in tissue regeneration. The wound healing capacity of bone marrow-derived mesenchymal stem cells (BM-MSCs), ESM, and their combination in rabbits with full-thickness skin defect (2 × 2 cm2) was evaluated. Twenty-five clinically healthy New Zealand White rabbits were divided into five groups of five animals each, with group A receiving no treatment (control group), group B receiving only fibrin glue (FG), group C receiving FG and ESM as a dressing, group D receiving FG and BM-MSCs, and group E receiving a combination of FG, ESM, and BM-MSCs. Wound healing was assessed using clinical, macroscopical, photographic, histological, histochemical, hematological, and biochemical analysis. Macroscopic examination of wounds revealed that healing was exceptional in group E, followed by groups D and C, compared to the control group. Histopathological findings revealed improved quality and a faster rate of healing in group E compared to groups A and B. In addition, healing in group B treated with topical FG alone was nearly identical to that in control group A. However, groups C and D showed improved and faster recovery than control groups A and B. The macroscopic, photographic, histological, and histochemical evaluations revealed that the combined use of BM-MSCs, ESM, and FG had superior and faster healing than the other groups.

3.
Mol Biol Evol ; 38(12): 5782-5805, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34469576

RESUMO

Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome data sets from natural populations of this species have been published over the last years. A major challenge is the integration of disparate data sets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 previously published and unpublished population samples from over 100 locations in >20 countries on four continents. Several of these locations have been sampled at different seasons across multiple years. This data set, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental metadata. A web-based genome browser and web portal provide easy access to the SNP data set. We further provide guidelines on how to use Pool-Seq data for model-based demographic inference. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan data set. Our resource will enable population geneticists to analyze spatiotemporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail.


Assuntos
Drosophila melanogaster , Metagenômica , Animais , Drosophila melanogaster/genética , Frequência do Gene , Genética Populacional , Genômica
4.
Epidemiol Infect ; 146(3): 314-318, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29338804

RESUMO

This report describes the effective public health response to a measles outbreak involving a university campus in Brisbane, Australia. Eleven cases in total were notified, mostly university students. The public health response included targeted measles vaccination clinics which were established on campus and focused on student groups most likely to have been exposed. The size of the university population, social interaction between students on and off campus, as well as limited vaccination records for the university community presented challenges for the control of this extremely infectious illness. We recommend domestic students ensure vaccinations are current prior to matriculation. Immunisation information should be included in university student enrolment packs. Incoming international students should ensure routine vaccinations are up-to-date prior to arrival in Australia, thereby reducing the risk of importation of measles and other infectious diseases.


Assuntos
Surtos de Doenças , Sarampo/epidemiologia , Saúde Pública , Universidades , Adulto , Feminino , Humanos , Masculino , Sarampo/virologia , Pessoa de Meia-Idade , Queensland/epidemiologia , Estudantes/estatística & dados numéricos , Adulto Jovem
5.
Epidemiol Infect ; 144(2): 371-80, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26122675

RESUMO

Drinking raw date palm sap is the primary route of Nipah virus (NiV) transmission from bats to people in Bangladesh; subsequent person-to-person transmission is common. During December 2010 to March 2011, we investigated NiV epidemiology by interviewing cases using structured questionnaires, in-depth interviews, and group discussions to collect clinical and exposure histories. We conducted a case-control study to identify risk factors for transmission. We identified 43 cases; 23 were laboratory-confirmed and 20 probable. Thirty-eight (88%) cases died. Drinking raw date palm sap and contact with an infected person were major risk factors; one healthcare worker was infected and for another case transmission apparently occurred through contact with a corpse. In absence of these risk factors, apparent routes of transmission included drinking fermented date palm sap. For the first time, a case was detected in eastern Bangladesh. Identification of new epidemiological characteristics emphasizes the importance of continued NiV surveillance and case investigation.


Assuntos
Surtos de Doenças , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/transmissão , Vírus Nipah/isolamento & purificação , Vírus Nipah/fisiologia , Adolescente , Adulto , Bangladesh/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Infecções por Henipavirus/mortalidade , Infecções por Henipavirus/virologia , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
Mymensingh Med J ; 25(3): 402-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27612882

RESUMO

Cervical cancer is the second most common cause of cancer related morbidity and mortality in women with 50% mortality rate. It is preventable if cervical cellular changes are detected and managed at early stage. This was a retrospective study conducted at VIA center of outpatient department and Colposcopy clinic at in-patient department of Mymensingh Medical College Hospital, Bangladesh covering a period from September 2013 to November 2014. Objective of this study was detection of cervical cancer and precancerous condition amongst patients reported to VIA center and Colposcopy clinic. In primary screening at VIA Center, total respondents were 3604, their mean age was 35.9 and highest were in the age group 31 to 40 years. At VIA center, 110(3.05%) were found positive and highest were between 31 to 40 years. In Colposcopy Clinic, out of 700 patients, 51.7% were CIN 1, 4.9% CIN 2, 1.4% CIN 3, invasive carcinoma was 0.3% and unsatisfactory or inconclusive were 34.3%. Most of the respondents were housewives and majority had poor monthly income. Amongst respondents, 72.1% were from rural area and Colposcopic findings revealed in 62.5% abnormal cervical changes, 46.5% were from rural area. Mean age at marriage or age at first coitus was found 16.25 years and 92.7% were in 11 to 20 years. Maximum abnormal cervical findings including CIN were between the ages ranged from 11 to 20 years of marriage age. In patients having 1 - 5 number of child having abnormal (58%) cervical changes, 48% were CIN 1. Histopathology reports found 19.6% CIN 1 (Total CIN 20.7%), cervical carcinoma 1.3%, inflammatory 7.0% and 0.42% cases were reported normal. Amongst 438 histopathology advised cases, 230 respondent's reports with patients were not available. VIA followed by Colposcopy has been a feasible, easy and reliable tools for screening cervical cancer in Bangladesh.


Assuntos
Colposcopia , Neoplasias do Colo do Útero , Ácido Acético , Adolescente , Adulto , Bangladesh , Criança , Colposcopia/métodos , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal , Adulto Jovem
7.
J Viral Hepat ; 22(11): 948-56, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25817821

RESUMO

We investigated an outbreak of jaundice in urban Bangladesh in 2010 to examine the cause and risk factors and assess the diagnostic utility of commercial assays. We classified municipal residents reporting jaundice during the preceding 4 weeks as probable hepatitis E cases and their neighbours without jaundice in the previous 6 months as probable controls. We tested the sera collected from probable cases and probable controls for IgM anti-hepatitis E virus (HEV), and the IgM-negative sera for IgG anti-HEV using a commercial assay locally. We retested the IgM-positive sera for both IgM and IgG anti-HEV using another assay at the Centre for Disease Control and Prevention (CDC), USA. Probable cases positive for IgM anti-HEV were confirmed cases; probable controls negative for both IgM and IgG anti-HEV were confirmed controls. We explored the local water supply and sanitation infrastructure and tested for bacterial concentration of water samples. Probable cases were more likely than probable controls to drink tap water (adjusted odds ratio: 3.4; 95% CI: 1.2-9.2). Fifty-eight percentage (36/62) of the case sera were IgM anti-HEV positive; and 75% of the IgM-positive samples were confirmed positive on retesting with another assay at CDC. Compared to confirmed controls, cases confirmed using either or both assays also identified drinking tap water as the risk factor. Two tap water samples had detectable thermotolerant coliforms. Research exploring decentralized water treatment technologies for sustainable safe water might prevent HEV transmission in resource-poor cities. Detection of serological markers in a majority of probable cases implied that available diagnostic assays could adequately identify HEV infection during outbreaks.


Assuntos
Surtos de Doenças , Hepatite E/epidemiologia , Icterícia/etiologia , População Urbana , Adolescente , Adulto , Bangladesh/epidemiologia , Estudos de Casos e Controles , Cidades/epidemiologia , Feminino , Anticorpos Anti-Hepatite/sangue , Hepatite E/diagnóstico , Hepatite E/patologia , Humanos , Imunoensaio , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Icterícia/diagnóstico , Icterícia/patologia , Masculino , Microbiologia da Água , Adulto Jovem
8.
Epidemiol Infect ; 143(9): 1922-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25342551

RESUMO

This paper explores the utility of cluster- and case-based surveillance established in government hospitals in Bangladesh to detect Nipah virus, a stage III zoonotic pathogen. Physicians listed meningo-encephalitis cases in the 10 surveillance hospitals and identified a cluster when ⩾2 cases who lived within 30 min walking distance of one another developed symptoms within 3 weeks of each other. Physicians collected blood samples from the clustered cases. As part of case-based surveillance, blood was collected from all listed meningo-encephalitis cases in three hospitals during the Nipah season (January-March). An investigation team visited clustered cases' communities to collect epidemiological information and blood from the living cases. We tested serum using Nipah-specific IgM ELISA. Up to September 2011, in 5887 listed cases, we identified 62 clusters comprising 176 encephalitis cases. We collected blood from 127 of these cases. In 10 clusters, we identified a total of 62 Nipah cases: 18 laboratory-confirmed and 34 probable. We identified person-to-person transmission of Nipah virus in four clusters. From case-based surveillance, we identified 23 (4%) Nipah cases. Faced with thousands of encephalitis cases, integrated cluster surveillance allows targeted deployment of investigative resources to detect outbreaks by stage III zoonotic pathogens in resource-limited settings.


Assuntos
Infecções Protozoárias do Sistema Nervoso Central/epidemiologia , Surtos de Doenças , Infecções por Henipavirus/epidemiologia , Vírus Nipah/fisiologia , Vigilância da População/métodos , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Animais , Bangladesh/epidemiologia , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Infecções Protozoárias do Sistema Nervoso Central/transmissão , Criança , Análise por Conglomerados , Feminino , Infecções por Henipavirus/parasitologia , Infecções por Henipavirus/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Zoonoses/parasitologia , Zoonoses/transmissão
9.
Mymensingh Med J ; 24(2): 263-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26007252

RESUMO

Sputum microscopy still remains the primary tool for the laboratory diagnosis of tuberculosis. A retrospective study was conducted in the directly observed treatment, short-course (DOTS) corner of Mymensingh Medical College Hospital (MMCH), in Bangladesh from May 2013 to May 2014. The study was designed to evaluate the extent of smear positive microscopy including multi-drug resistance (MDR) amongst tuberculosis suspected cases. A total of 2,361 Pulmonary Tuberculosis (PTB) suspects were noticed to DOTS corner during this period, with the mean age of 43 years. The male female ratio was 2.02:1 and the smear positivity rate was about 10%. Study found majority of the suspects were in the economically productive year of life 20-70 years. Smear negative suspects were not re-evaluated further, though smear negativity does not rule out absence of tuberculosis. Extra pulmonary or non tuberculous mycobacteria were not evaluated in this study. Twenty two patients 0.9% of total 2361 were identified as MDR during the study period where 61 clinically highly suspected cases were sent for GeneXpert that seems to be much lesser than the national rate (3.6% in new cases and 19% in retreated cases). The smear positivity rate of all three (1st, 2nd and 3rd) smear was 94.5%, all the second smear was 100% positive and the third were 95.47% positive. It is evident from this study that two smear microscopy was found sufficiently reliable to diagnose TB. However, further in depth prospective study might be undertaken to ascertain the scenario of this chronic diseases.


Assuntos
Tuberculose , Adulto , Bangladesh , Feminino , Humanos , Masculino , Estudos Retrospectivos , Escarro
10.
J Periodontal Res ; 49(6): 836-44, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24620793

RESUMO

BACKGROUND AND OBJECTIVE: Various epidemiological studies have implied that local infection may increase the levels of systemic inflammatory mediators and lipid mediators, thereby promoting atherosclerosis. The aim of this study was to assess high-sensitivity C-reactive protein (HsCRP) and lipid levels in healthy adults and patients with coronary artery disease (CAD), with and without periodontitis. MATERIAL AND METHODS: A total of 100 subjects were included in the study and categorized into four groups of 25 subjects each, as follows: subjects with chronic periodontitis with angiographically proven CAD; nonperiodontitis subjects with angiographically proven CAD; otherwise healthy subjects with only chronic periodontitis; and systemically and orally healthy individuals. The periodontal parameters measured included plaque index, gingival index, probing pocket depth, clinical attachment level and marginal alveolar bone loss (which was recorded radiographically). Serum samples were collected for estimation of HsCRP, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglycerides (TGs). RESULTS: The serum HsCRP levels in subjects with either CAD or chronic periodontitis were elevated two-fold compared with those of healthy individuals, whereas in subjects with both diseases (CAD plus chronic periodontitis) the levels were elevated three-fold. The serum LDL level was higher, and the serum HDL level was lower, in all the test groups compared with the healthy group. No significant difference among the groups was detected in the TG levels. CONCLUSION: A persistent infection, such as chronic periodontitis, may influence changes in the systemic levels of HsCRP, LDL and HDL, which potentially have an impact on inflammation-associated atherosclerotic processes, such as CAD.


Assuntos
Proteína C-Reativa/análise , Periodontite Crônica/sangue , Doença da Artéria Coronariana/sangue , Lipídeos/sangue , Adulto , Idoso , Perda do Osso Alveolar/classificação , Perda do Osso Alveolar/diagnóstico por imagem , Glicemia/análise , Periodontite Crônica/complicações , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Estudos Transversais , Índice de Placa Dentária , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Pessoa de Meia-Idade , Perda da Inserção Periodontal/classificação , Índice Periodontal , Bolsa Periodontal/classificação , Radiografia Interproximal , Triglicerídeos/sangue
11.
Mymensingh Med J ; 23(2): 272-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24858154

RESUMO

Breast cancer with advanced stage is common in Bangladeshi women. For the treatment of this deadly disease neoadjuvant chemotherapy (NAT) is the recent standard of care. NAT is useful for down-staging and to prevent micro-metastasis of tumour, on the other hand it causes variable clinical and pathological responses. This observational study was aimed to evaluate the morphological changes in neoplastic, nonneoplastic breast tissue and in the lymph nodes after NAT. To identify the clinical response and post operative histologic changes, this study prospectively selected 35 patients with locally advanced breast cancer treated with NAT. In these patients clinical response was assessed based on tumour size. Mastectomy specimens were collected and samplings were done in specific method. Majority (68%) of patients presented with breast lump measuring over 5cm with enlarged lymph nodes. After NAT the lump size reduced to <5cm and lymph nodes became nonpalpable in most (60%) of the patient. Complete clinical response (cCR) was observed in five patients. For histopathological evaluation, the tumour cellularity was semi quantitatively measured. Seventeen percent (17%) patient presented with 50% tumour cellularity in tumour bed. Most striking cytologic atypia was nuclear changes. The characteristic patterns of stomal changes were observed. Only 8 patients showed nonneoplastic breast tissue changes. In lymph nodes hyaline stromal scar was most commonly (23%) seen. This study observed that 2 patients had pathological complete response out of 5 clinically complete response patients. This study concluded that the knowledge of morphologic spectrum of treatment-induced breast tissue change is important for the pathologist to avoid misdiagnosis. This will help the clinician to take rational decision for management of the locally advanced breast cancer.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma/patologia , Carcinoma/terapia , Adulto , Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Terapia Neoadjuvante , Adulto Jovem
12.
Indian J Orthop ; 58(7): 932-943, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38948364

RESUMO

Background: In bone tissue engineering segment, numerous approaches have been investigated to address critically sized bone defects via 3D scaffolds, as the amount of autologous bone grafts are limited, accompanied with complications on harvesting. Moreover, the use of bone-marrow-derived stem cells is also a limiting factor owing to the invasive procedures involved and the low yield of stem cells. Hence, research is ongoing on the search for an ideal bone graft system promoting bone growth and regeneration. Purpose of the Study: This study aims to develop a unique platform for tissue development via stem cell differentiation towards an osteogenic phenotype providing optimum biological cues for cell adhesion, differentiation and proliferation using biomimetic gelatin-based scaffolds. The use of adipose-derived mesenchymal stem cells in this study also offers an ideal approach for the development of an autologous bone graft. Methods: A gelatin-vinyl acetate-based 3D scaffold system incorporating Bioglass was developed and the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADMSCs) on the highly porous freeze-dried gelatin-vinyl acetate/ Bioglass scaffold (GB) system was analyzed. The physicochemical properties, cell proliferation and viability were investigated by seeding rat adipose tissue-derived mesenchymal stem cells (ADSCs) onto the scaffolds. The osteogenic differentiation potential of the ADMSC seeded GeVAc/bioglass system was assessed using calcium deposition assay and bone-related protein and genes and comparing with the 3D Gelatin vinyl acetate coppolymer (GeVAc) constructs. Results and Conclusion: According to the findings, the 3D porous GeVAc/bioglass scaffold can be considered as a promising matrix for bone tissue regeneration and the 3D architecture supports the differentiation of the ADMSCs into osteoblast cells and enhances the production of mineralized bone matrix.

13.
Vet Res Commun ; 48(3): 1973-1976, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38671338

RESUMO

The widespread application of mesenchymal stem cells (MSCs) in veterinary regenerative medicine highlights their promising therapeutic potential. However, the lack of standardized characterization and reporting practices across studies poses a significant challenge, compromising the assessment of their safety and efficacy. While criteria established for human MSCs serve as a foundation, the unique characteristics of animal-derived MSCs warrant updated guidelines tailored to veterinary medicine. A recent position statement outlining minimal reporting criteria for MSCs in veterinary research reflects efforts to address this need, aiming to enhance research quality and reproducibility. Standardized reporting criteria ensure transparency, facilitate evidence synthesis, and promote best practices adoption in MSC isolation, characterization, and administration. Adherence to minimal reporting criteria is crucial for maintaining scientific rigor and advancing the field of veterinary regenerative medicine. Ongoing collaboration among stakeholders is essential for effective implementation and adherence to updated guidelines, fostering excellence and innovation in MSC-based therapies for animal patients.


Assuntos
Células-Tronco Mesenquimais , Medicina Regenerativa , Animais , Medicina Regenerativa/normas , Células-Tronco Mesenquimais/citologia , Transplante de Células-Tronco Mesenquimais/veterinária , Transplante de Células-Tronco Mesenquimais/normas , Transplante de Células-Tronco Mesenquimais/métodos , Medicina Veterinária/normas , Medicina Veterinária/métodos
14.
Top Companion Anim Med ; 58: 100840, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37979613

RESUMO

Platelets contain a multitude of growth factors and play a crucial role in physiological processes such as thrombogenesis, tissue repair, and angiogenesis. As a result, platelet-derived products have significant potential for efficient utilization in the realm of regenerative medicine due to their therapeutic and biological attributes. Numerous studies have already substantiated the therapeutic viability of platelets in various canine ailments. The existing literature indicates a substantial surge in the clinical application of canine platelets, positioning platelet-derived products as a viable alternative to conventional therapeutic agents. Platelet concentrates, including platelet-rich plasma and platelet-rich fibrin are commonly used as a therapeutic modality in clinical cases. These therapeutic derivatives exhibit effectiveness in tissue regeneration and can serve as complementary therapies. Notably, they offer a cost-effective and easily accessible therapeutic option, which has demonstrated its benefits in chronic inflammatory disorders such as osteoarthritis and tendinitis, ophthalmic conditions, wound healing, and mandibular injuries in canine patients. The broad spectrum of therapeutic effects displayed by platelets is providing researchers with novel perspectives for crafting therapeutic models in future investigations. This review centers on exploring the therapeutic potential of canine platelets across diverse disorders. Further exploration into platelet products, encompassing their preparation and applicability in canine medicine, is imperative. These inquiries hold the promise of unveiling fresh horizons for the domain of regenerative medicine.


Assuntos
Doenças do Cão , Osteoartrite , Plasma Rico em Plaquetas , Animais , Cães , Plaquetas , Cicatrização , Plasma Rico em Plaquetas/fisiologia , Medicina Regenerativa , Osteoartrite/veterinária , Doenças do Cão/tratamento farmacológico
15.
Tissue Cell ; 88: 102380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615643

RESUMO

The use of mesenchymal stem cells (MSCs) in cartilage regeneration has gained significant attention in regenerative medicine. This paper reviews the molecular mechanisms underlying MSC-based cartilage regeneration and explores various therapeutic strategies to enhance the efficacy of MSCs in this context. MSCs exhibit multipotent capabilities and can differentiate into various cell lineages under specific microenvironmental cues. Chondrogenic differentiation, a complex process involving signaling pathways, transcription factors, and growth factors, plays a pivotal role in the successful regeneration of cartilage tissue. The chondrogenic differentiation of MSCs is tightly regulated by growth factors and signaling pathways such as TGF-ß, BMP, Wnt/ß-catenin, RhoA/ROCK, NOTCH, and IHH (Indian hedgehog). Understanding the intricate balance between these pathways is crucial for directing lineage-specific differentiation and preventing undesirable chondrocyte hypertrophy. Additionally, paracrine effects of MSCs, mediated by the secretion of bioactive factors, contribute significantly to immunomodulation, recruitment of endogenous stem cells, and maintenance of chondrocyte phenotype. Pre-treatment strategies utilized to potentiate MSCs, such as hypoxic conditions, low-intensity ultrasound, kartogenin treatment, and gene editing, are also discussed for their potential to enhance MSC survival, differentiation, and paracrine effects. In conclusion, this paper provides a comprehensive overview of the molecular mechanisms involved in MSC-based cartilage regeneration and outlines promising therapeutic strategies. The insights presented contribute to the ongoing efforts in optimizing MSC-based therapies for effective cartilage repair.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Regeneração , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Regeneração/fisiologia , Animais , Condrogênese/fisiologia , Cartilagem/metabolismo , Cartilagem/fisiologia , Diferenciação Celular , Condrócitos/metabolismo , Condrócitos/citologia , Transdução de Sinais
16.
Curr Res Transl Med ; 72(4): 103458, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38943898

RESUMO

Hydrogels are commonly used as carriers for cell delivery due to their similarities to the extracellular matrix. A contraction-suppressed full-thickness wound model was used to evaluate the therapeutic potential of Pluronic F127 (PF127) hydrogel loaded with adipose-derived stromal vascular fraction (AdSVF), mesenchymal stem cells (AdMSC), and conditioned media (AdMSC-CM) for the repair of wounds in a rabbit model. The experimental study was conducted on forty-eight healthy adult New Zealand white rabbits randomly divided into eight groups with six animals each and treated with AdSVF, AdMSC, and AdMSC-CM as an injectable or topical preparation. The healing potential of different adipose-derived cell-based and cell-free therapeutics was evaluated based on percentage wound healing, period of epithelialization, epidermal thickness, scar evaluation, histopathology analysis, histochemical evaluation, immunohistochemistry (collagen type I), and hydroxyproline assay by comparing with the positive and negative control. Collagen density analysis using different staining methods, immunohistochemistry, and hydroxyproline assay consistently showed that delivering AdMSC and AdMSC-CM in PF127 hydrogel enhanced epithelialization, collagen production, and organization, contributing to improved tissue strength and quality. Even though allogeneic AdSVF was found to promote wound healing in rabbits, it has a lower potential than AdMSC and AdMSC-CM. The wound healing potential of AdMSC and AdMSC-CM was enhanced when loaded in PF127 hydrogel and applied topically. Even though wounds treated with AdMSC outperformed AdMSC-CM, a significant difference in the healing quality was not observed in most instances, indicating almost similar therapeutic potential. The findings indicate that the wound healing potential of AdMSC and AdMSC-CM was enhanced when loaded in PF127 hydrogel and applied topically. These treatments promoted collagen production, tissue organization, and epidermal regeneration, ultimately improving overall healing outcomes.

17.
Clin Cancer Res ; 30(2): 263-268, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37610803

RESUMO

On March 16, 2023, the FDA approved dabrafenib in combination with trametinib (Tafinlar, Mekinist; Novartis Pharmaceuticals Corporation) for the treatment of pediatric patients with low-grade glioma (LGG) with a BRAFV600E mutation who require systemic therapy. FDA also approved oral formulations of both drugs suitable for patients who cannot swallow pills. This approval was based on the LGG cohort from study CDRB436G2201 (NCT02684058), a multicenter, open-label trial in which pediatric patients with LGG with a BRAFV600E mutation were randomly assigned 2:1 to dabrafenib plus trametinib (D+T) or carboplatin plus vincristine (C+V). The overall response rate (ORR) by independent review based on Response Assessment in Neuro-oncology LGG (2017) criteria was assessed in 110 patients randomly assigned to D+T (n = 73) or C+V (n = 37). ORR was 47% [95% confidence interval (CI), 35-59] in the D+T arm and 11% (95% CI, 3.0-25) in the C+V arm. Duration of response (DOR) was 23.7 months (95% CI, 14.5-NE) in the D+T arm and not estimable (95% CI, 6.6- NE) in the C+V arm. Progression-free survival (PFS) was 20.1 months (95% CI: 12.8, NE) and 7.4 months (95% CI, 3.6- 11.8) [HR, 0.31 (95% CI, 0.17-0.55); P < 0.001] in the D+T and C+V arms, respectively. The most common (>20%) adverse reactions were pyrexia, rash, headache, vomiting, musculoskeletal pain, fatigue, diarrhea, dry skin, nausea, hemorrhage, abdominal pain, and dermatitis acneiform. This represents the first FDA approval of a systemic therapy for the first-line treatment of pediatric patients with LGG with a BRAFV600E mutation.


Assuntos
Glioma , Imidazóis , Piridonas , Humanos , Criança , Piridonas/efeitos adversos , Pirimidinonas , Oximas , Glioma/tratamento farmacológico , Glioma/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
18.
Mymensingh Med J ; 22(3): 613-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23982561

RESUMO

Human immunodeficiency virus associated nephropathy (HIVAN) is clinically and morphologically a distinctive type of renal parenchymal disorder. It is presented in an HIV-seropositive individual by proteinuria and progressive renal insufficiency, usually without oedema or hypertension. Renal biopsy most commonly reveals a collapsing form of focal segmental glomerulosclerosis with marked proliferation of glomerular podocytes and tubular microcystic dilatation. These characteristic changes are attributed to incorporation of DNA and mRNA of human immunodeficiency virus type 1 into the renal parenchymal cells. Newly introduced highly active anti-retroviral therapy (HAART) has significantly reduced the incidence of HIVAN in the recent years. The HAART has been found to retard and revert the progression of renal insufficiency towards end-stage renal disease, and to increase survival of the patient. Therefore a renal biopsy should be performed in all suspected patients for definitive diagnosis of HIVAN and better patient management.


Assuntos
Nefropatia Associada a AIDS/diagnóstico , Nefropatia Associada a AIDS/patologia , Nefropatia Associada a AIDS/terapia , Biópsia , Diagnóstico Diferencial , Progressão da Doença , Humanos , Prognóstico
19.
Ann Med Surg (Lond) ; 85(10): 5275-5278, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37811040

RESUMO

Stem cell research has the transformative potential to revolutionize medicine. Language models like ChatGPT, which use artificial intelligence (AI) and natural language processing, generate human-like text that can aid researchers. However, it is vital to ensure the accuracy and reliability of AI-generated references. This study assesses Chat Generative Pre-Trained Transformer (ChatGPT)'s utility in stem cell research and evaluates the accuracy of its references. Of the 86 references analyzed, 15.12% were fabricated and 9.30% were erroneous. These errors were due to limitations such as no real-time internet access and reliance on preexisting data. Artificial hallucinations were also observed, where the text seems plausible but deviates from fact. Monitoring, diverse training, and expanding knowledge cut-off can help to reduce fabricated references and hallucinations. Researchers must verify references and consider the limitations of AI models. Further research is needed to enhance the accuracy of such language models. Despite these challenges, ChatGPT has the potential to be a valuable tool for stem cell research. It can help researchers to stay up-to-date on the latest developments in the field and to find relevant information.

20.
ACS Omega ; 8(15): 13799-13812, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37091371

RESUMO

A fascinating transition-metal dichalcogenide (TMDC) compound, MoSe2, has attracted a lot of interest in electrochemical, photocatalytic, and optoelectronic systems. However, detailed studies on the structural stability of the various MoSe2 polymorphs are still lacking. For the first time, the relative stability of 11 different MoSe2 polymorphs (1H, 2H, 3Ha, 3Hb, 2T, 4T, 2R1, 1T1, 1T2, 3T, and 2R2) is proposed, and a detailed analysis of these polymorphs is carried out by employing the first-principles calculations based on density functional theory (DFT). We computed the physical properties of the polymorphs such as band structure, phonon, and elastic constants to examine the viability for real-world applications. The electronic properties of the involved polymorphs were calculated by employing the hybrid functional of Heyd, Scuseria, and Ernzerhof (HSE06). The energy band gap of the polymorphs (1H, 2H, 3Ha, 3Hb, 2T, 4T, and 2R1) is in the range of 1.6-1.8 eV, coinciding with the experimental value for the polymorph 2H. The covalent bonding nature of MoSe2 is analyzed from the charge density, charge transfer, and electron localization function. Among the 11 polymorphs, 1H, 2H, 2T, and 3Hb polymorphs are predicted as stable polymorphs based on the calculation of the mechanical and dynamical properties. Even though the 4T and 3Ha polymorphs' phonons are stable, they are mechanically unstable; hence, they are considered to be under a metastable condition. Additionally, we computed the direction-dependent elastic moduli and isotropic factors for both mechanically and dynamically stable polymorphs. Stable polymorphs are analyzed spectroscopically using IR and Raman spectra. The thermal stability of the polymorphs is also studied.

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