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1.
Environ Monit Assess ; 196(8): 727, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995471

RESUMO

The present study provides an assessment of the distribution of key Non-Timber Forest Product species in India, namely Aegle marmelos (L.) Correa, Buchanania lanzan Spreng., Madhuca longifolia (J. Koenig ex L.) J. F. Macbr., Phyllanthus emblica L. and Terminalia bellirica (Gaertn.) Roxb. The suitable habitat was analyzed under current climate scenarios and subsequently, the future distribution (2050s and 2070s) was mapped under RCP 2.6 and 8.5 scenarios, along with the past distribution (mid-Holocene, ~ 6000 cal year BP) using the MaxEnt species distribution model. The distribution of all species is primarily driven by key bioclimatic factors, including annual precipitation (Bio_12), mean annual temperature (Bio_1), isothermality (Bio_3) and precipitation of the coldest quarter (Bio_19). The results indicate that the present distribution of these species is mainly centred in the Western Ghats regions, Central Highlands, North-eastern India and Siwalik hills. The current study suggests that under the future climate change, the suitable habitat for A. marmelos and T. bellirica is expected to increase while for B. lanzan, M. longifolia and P. emblica, it is projected to decline. A. marmelos and T. bellirica are anticipated to exhibit resilience to future climate changes and are expected to be minimally affected, while B. lanzan, M. longifolia and P. emblica are highly sensitive to high temperature and alteration in rainfall pattern expected under future climate changes. The projections of habitat suitability areas can be used as a valuable foundation for developing conservation and restoration strategies aimed at alleviating the climate change impacts on NTFP species.


Assuntos
Mudança Climática , Florestas , Clima Tropical , Índia , Ecossistema , Monitoramento Ambiental , Árvores , Conservação dos Recursos Naturais
2.
Proc Natl Acad Sci U S A ; 115(29): E6956-E6963, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29967142

RESUMO

A majority of emerging infectious diseases in humans are zoonoses. Understanding factors that influence the emergence and transmission of zoonoses is pivotal for their prevention and control. Toxoplasma gondii is one of the most widespread zoonotic pathogens known today. Whereas only a few genotypes of T. gondii dominate in the Northern Hemisphere, many genotypes coexist in South America. Furthermore, T. gondii strains from South America are more likely to be virulent than those from the Northern Hemisphere. However, it is not clear what factor(s) shaped modern-day genetic diversity and virulence of T. gondii Here, our analysis suggests that the rise and expansion of farming in the past 11,000 years established the domestic cat/mouse transmission cycle for T. gondii, which has undoubtedly played a significant role in the selection of certain linages of T. gondii Our mathematical simulations showed that within the domestic transmission cycle, intermediately mouse-virulent T. gondii genotypes have an adaptive advantage and eventually become dominant due to a balance between lower host mortality and the ability to superinfect mice previously infected with a less virulent T. gondii strain. Our analysis of the global type II lineage of T. gondii suggests its Old World origin but recent expansion in North America, which is likely the consequence of global human migration and trading. These results have significant implications concerning transmission and evolution of zoonotic pathogens in the rapidly expanding anthropized environment demanded by rapid growth of the human population and intensive international trading at present and in the future.


Assuntos
Toxoplasma/genética , Toxoplasma/patogenicidade , Toxoplasmose/genética , Toxoplasmose/transmissão , Zoonoses/genética , Zoonoses/transmissão , Animais , Gatos , Migração Humana , Humanos , Camundongos , América do Sul , Toxoplasmose/mortalidade , Zoonoses/mortalidade
3.
Exp Parasitol ; 174: 25-30, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28153801

RESUMO

Toxoplasma gondii is one of the most successful pathogens on earth, capable of infecting an extremely broad range of mammals and birds and causing potentially fatal disease in humans. The house mouse (Mus musculus) has been used as the primary laboratory animal model for determining the virulence of T. gondii strains. Epidemiological evidence also suggests a potential association between virulence in mice and disease severity in human toxoplasmosis. However, many factors can affect virulence measurements, including route of infection, life stage of the parasite, number of passages of the parasite in mice or cell culture, and the mouse host line used. Variability among these factors makes it difficult to compare results between different studies in different laboratories. Here, we discuss important factors that should be considered when carrying out T. gondii murine virulence assays and propose a standardized methodology that should facilitate integration of T. gondii virulence data throughout the research community in future studies and thereby enable more efficient and effective analysis of genetic and virulence patterns for this important parasite.


Assuntos
Modelos Animais de Doenças , Camundongos Endogâmicos , Toxoplasma/patogenicidade , Toxoplasmose Animal/parasitologia , Animais , Suscetibilidade a Doenças , Genótipo , Humanos , Camundongos , Fenótipo , Toxoplasma/genética , Toxoplasma/crescimento & desenvolvimento , Toxoplasmose Animal/mortalidade , Virulência
4.
Cureus ; 16(4): e58682, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38774176

RESUMO

OBJECTIVES: Sepsis is one of the leading causes of morbidity and mortality worldwide, and culture-negative sepsis, despite its prevalence, is largely understudied. The current study intends to examine clinical characteristics and biomarkers in culture-positive and culture-negative sepsis, focusing on 30-day mortality and duration of hospital stay in both groups.  Materials and methods: A prospective observational comparative cohort study was done on 150 patients admitted to the intensive care unit (ICU) and wards of Jaipur Golden Hospital. Patients with documented fungal, viral, or parasitic infections, as well as those who had undergone surgery or experienced trauma, were excluded.  Results: The mean age of the patients was 51.31±18.94 years. Of 150 patients, 95 (63.3%) were culture-negative, whereas 55 (36.7%) were culture-positive, with more men in the former and more women in the latter. Patients with negative cultures had fewer comorbidities. The levels of procalcitonin (PCT), C-reactive protein (CRP), and serum lactate were within the prescribed limit for both culture-negative and positive patients. A higher proportion (87.3%) of the organisms isolated from culture-positive individuals were gram-negative, with Escherichia coli (E. coli) having the highest prevalence (27.3%), followed by Klebsiella (20%). There were 12.7% gram-positive isolates. The culture-negative patients had significantly better outcomes (P=0.003) as well as the duration of hospital stay (P<0.001) than the culture-positive patients. Culture-positive patients had a more severe illness, a higher incidence of septic shock, and a higher fatality rate than culture-negative patients. CONCLUSION: It can be concluded that CRP and PCT can be used as clinically reliable sepsis biomarkers in both culture-positive and culture-negative patients. The study found that culture-negative sepsis is more prevalent and that there are substantial differences between culture-negative and culture-positive sepsis, with the former group having fewer comorbidities, less severe illness, a shorter duration of hospital stays, lower death rates, and better outcomes.

5.
Cell Rep ; 29(12): 3916-3932.e5, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31851923

RESUMO

Non-recirculating tissue-resident memory T cells (TRMs) are the predominant T cell subset in diverse tissue sites, where they mediate protective immune responses in situ. Here, we reveal a role for TRM in maintaining immune homeostasis in the human pancreas through interactions with resident macrophages and the PD-1/PD-L1 inhibitory pathway. Using tissues obtained from organ donors, we identify that pancreas T cells comprise CD8+PD-1hi TRMs, which are phenotypically, functionally, and transcriptionally distinct compared to TRMs in neighboring jejunum and lymph node sites. Pancreas TRMs cluster with resident macrophages throughout the exocrine areas; TRM effector functions are enhanced by macrophage-derived co-stimulation and attenuated by the PD-1/PD-L1 pathways. Conversely, in samples from chronic pancreatitis, TRMs exhibit reduced PD-1 expression and reduced interactions with macrophages. These findings suggest important roles for PD-1 and TRM-macrophage interactions in controlling tissue homeostasis and immune dysfunctions underlying inflammatory disease, with important implications for PD-1-based immunotherapies.


Assuntos
Antígeno B7-H1/metabolismo , Memória Imunológica/fisiologia , Pâncreas/metabolismo , Pancreatite/imunologia , Pancreatite/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Subpopulações de Linfócitos T/metabolismo , Antígeno B7-H1/genética , Antígenos CD58/metabolismo , Humanos , Imunidade nas Mucosas/genética , Imunidade nas Mucosas/fisiologia , Memória Imunológica/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Pâncreas/imunologia , Pâncreas/patologia , Pancreatite/genética , Receptor de Morte Celular Programada 1/genética , Transdução de Sinais , Subpopulações de Linfócitos T/imunologia
6.
Stem Cell Res Ther ; 9(1): 26, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29394953

RESUMO

BACKGROUND: Radiation-induced gastrointestinal syndrome (RIGS) results from the acute loss of intestinal stem cells (ISC), impaired epithelial regeneration, and subsequent loss of the mucosal barrier, resulting in electrolyte imbalance, diarrhea, weight loss, sepsis, and mortality. The high radiosensitivity of the intestinal epithelium limits effective radiotherapy against abdominal malignancies and limits the survival of victims of nuclear accidents or terrorism. Currently, there is no approved therapy to mitigate radiation toxicity in the intestine. Here we demonstrate that BCN057, an anti-neoplastic small molecular agent, induces ISC proliferation and promotes intestinal epithelial repair against radiation injury. METHODS: BCN057 (90 mg/kg body weight, subcutaneously) was injected into C57Bl6 male mice (JAX) at 24 h following abdominal irradiation (AIR) and was continued for 8 days post-irradiation. BCN057-mediated rescue of Lgr5-positive ISC was validated in Lgr5-EGFP-Cre-ERT2 mice exposed to AIR. The regenerative response of Lgr5-positive ISC was examined by lineage tracing assay using Lgr5-EGFP-ires-CreERT2-TdT mice with tamoxifen administration to activate Cre recombinase and thereby marking the ISC and their respective progeny. Ex vivo three-dimensional organoid cultures were developed from surgical specimens of human colon or from mice jejunum and were used to examine the radio-mitigating role of BCN057 on ISC ex vivo. Organoid growth was determined by quantifying the budding crypt/total crypt ratio. Statistical analysis was performed using Log-rank (Mantel-Cox) test and paired two-tail t test. RESULTS: Treatment with BCN057 24 h after a lethal dose of AIR rescues ISC, promotes regeneration of the intestinal epithelium, and thereby mitigates RIGS. Irradiated mice without BCN057 treatment suffered from RIGS, resulting in 100% mortality within 15 days post-radiation. Intestinal organoids developed from mice jejunum or human colon demonstrated a regenerative response with BCN057 treatment and mitigated radiation toxicity. However, BCN057 did not deliver radio-protection to mouse or human colon tumor tissue. CONCLUSION: BCN057 is a potential mitigator against RIGS and may be useful for improving the therapeutic ratio of abdominal radiotherapy. This is the first report demonstrating that a small molecular agent mitigates radiation-induced intestinal injury by inducing ISC self-renewal and proliferation.


Assuntos
Raios gama/efeitos adversos , Enteropatias/prevenção & controle , Mucosa Intestinal/metabolismo , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Células-Tronco/metabolismo , Animais , Enteropatias/metabolismo , Enteropatias/patologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Lesões por Radiação/metabolismo , Lesões por Radiação/patologia , Protetores contra Radiação/química , Células-Tronco/patologia
7.
Oncomedicine ; 2: 156-167, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29445586

RESUMO

The unfolded protein response (UPR) is an established and well-studied cellular response to the stress and serves to relieve the stress and reinstate cellular homeostasis. It occurs in the endoplasmic reticulum (ER), responsible of properly folding and processing of secretory and transmembrane proteins. It is extremely sensitive to alteration in homeostasis caused by various internal or external stressors which leads to accumulation of misfolded or unfolded proteins in the ER lumen. The UPR works by restoring protein homeostasis in the ER, either through the boosting of protein-folding and degradation capability or by assuaging the demands for such effects, and can cause the activation of cell death if unable to do so. Cancer cells have adapted to gain advantage from the UPR and keeping the cell away from apoptosis and promoting survival, including survival of the cancer stem cells and evading the immune system. Several components of the UPR are overexpressed in a malignant cell and are responsible for resistance from various chemotherapy options and radiotherapy, which are also responsible for causing ER stress and activating the UPR. In this review, we discuss the various ways in which UPR can aid different cancers to survive and evade therapy and highlight recent research, which exploits the UPR to confer sensitivity to these cancer cells against various drugs and radiation.

8.
Parasit Vectors ; 10(1): 508, 2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-29061166

RESUMO

BACKGROUND: Toxoplasma gondii is a widespread protozoan parasite that infects humans and other animals. Previous studies indicate some genotypes of T. gondii are more frequently isolated in wildlife than agricultural animals, suggesting a wild/feral animal diversity model. To determine seroprevalence and genetic diversity of T. gondii in southeastern US wildlife, we collected sera from 471 wild animals, including 453 mammals and 18 birds, between 2011 and 2014. These serum samples were assayed for T. gondii infection using the modified agglutination test (MAT). Heart or tongue tissues from 66 seropositive animals were bioassayed in mice and 19 isolates were obtained. The isolated parasites were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method employing 10 genetic markers. RESULTS: One hundred and ninety-six of 471 samples (41.6%) had a titer ≥1:32 and were considered positive for T. gondii infection. Of 453 mammals, 195 (43%) were seropositive, whereas only one (5.6%) of 18 birds was seropositive. The seroprevalence in mammals was significantly higher than in the birds. Mammalian hosts with adequate samples size (≥ 20) comprised white-tailed deer (n = 241), feral hogs (n = 100), raccoons (n = 34) and coyotes (n = 22), with seroprevalences of 41.0%, 51.0%, 50.0% and 72.7%, respectively. Coyotes had significantly higher seroprevalence than the white-tailed deer. Genotyping revealed five distinct genotypes, including the ToxoDB PCR-RFLP genotype #5 (a.k.a type 12) for 15 isolates, genotype #3 (a.k.a. type II) for 1 isolate, and genotypes #154, #167 and #216, each for 1 isolate. The results showed moderate to high infection rates of T. gondii in white-tailed deer, feral hogs, raccoons and coyotes. Genotyping results indicated limited genetic diversity and a dominance of genotype #5, which has been reported as a major type in wildlife in North America. CONCLUSIONS: We conclude that T. gondii infection is common in game animals (white-tailed deer and feral hogs) in the southeastern US, which may pose a food safety risk to humans. Further research is necessary to understand T. gondii transmission from wildlife to farm animals and humans.


Assuntos
Animais Selvagens/parasitologia , Anticorpos Antiprotozoários/sangue , Variação Genética , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Testes de Aglutinação , Animais , Bioensaio , DNA de Protozoário/genética , Cervos/parasitologia , Genótipo , Coração/parasitologia , Humanos , Camundongos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Estudos Soroepidemiológicos , Sudeste dos Estados Unidos/epidemiologia , Língua/parasitologia , Toxoplasmose Animal/parasitologia
9.
Virology ; 485: 153-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26264969

RESUMO

As prostate tumor cell growth depends on hormones, androgen ablation is an effective therapy for prostate cancer (PCa). However, progression of PCa cells to androgen independent growth (castrate resistant prostate cancer, CRPC) results in relapse and mortality. Hypoxia, a microenvironment of low oxygen that modifies the activity of PCa regulatory proteins including the androgen receptor (AR), plays a critical role in progression to CRPC. Therapies targeting hypoxia and the AR may lengthen the time to CRPC progression thereby increasing survival time of PCa patients. Mammalian Orthoreovirus (MRV) has shown promise for the treatment of prostate tumors in vitro and in vivo. In this study, we found that MRV infection induces downregulation of proteins implicated in CRPC progression, interferes with hypoxia-induced AR activity, and induces apoptosis in androgen dependent cells. This suggests MRV possesses traits that could be exploited to create novel therapies for the inhibition of progression to CRPC.


Assuntos
Regulação Neoplásica da Expressão Gênica , Vírus Oncolíticos/genética , Orthoreovirus de Mamíferos/genética , Próstata/virologia , Receptores Androgênicos/genética , Androgênios/metabolismo , Apoptose/genética , Hipóxia Celular , Linhagem Celular Tumoral , Humanos , Calicreínas/genética , Calicreínas/metabolismo , Masculino , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/metabolismo , Orthoreovirus de Mamíferos/metabolismo , Próstata/metabolismo , Próstata/patologia , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Androgênicos/metabolismo , Transdução de Sinais
10.
Oncotarget ; 5(2): 561-74, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24504474

RESUMO

Hypoxia has emerged as one of the most important drivers of tumor aggression, metastasis, and poor clinical outcome in many cancers.In prostate cancer (PCa), hypoxia has been strongly correlated to biochemical failure and local recurrence. However, current PCa treatment options do not address hypoxic cells highlighting a critical gap in existing therapies and the need for development of therapies that target hypoxic prostate tumor cells. Mammalian orthoreovirus (MRV) is an oncolytic virus that targets tumor cells over normal cells which has been shown to be safe and effective against many cancers in vitro, in animal models, and in human clinical trials. We found that MRVinfects and replicates in hypoxic prostate tumor cells to levels comparable to normoxic cells leading to apoptosis and cell death. In addition, the regulatory subunit (HIF-1α) of the master transcriptional regulator of hypoxia, HIF-1, was significantly downregulated in infected cells. HIF-1α downregulation was found to occur via ubiquitin-dependent proteasome-mediated degradation and translational inhibition. Virus-mediated HIF-1α degradation required the HIF-1α PAS domain and expression of the receptor for activated kinase C (RACK1) protein. These data provide evidence that MRV may be a viable therapeutic option for targeting hypoxic cells and HIF-1α in PCa.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/virologia , Infecções por Reoviridae/metabolismo , Fatores de Transcrição/genética , Apoptose/fisiologia , Hipóxia Celular/fisiologia , Progressão da Doença , Regulação para Baixo , Humanos , Masculino , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/virologia , Orthoreovirus de Mamíferos , Neoplasias da Próstata/patologia , Infecções por Reoviridae/patologia , Transfecção
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