Fetal liver and adult bone marrow hematopoietic stem cells (HSCs) renew or differentiate into committed progenitors to generate all blood cells. PRDM16 is involved in human leukemic translocations and is expressed highly in some karyotypically normal acute myeloblastic leukemias. As many genes involved in leukemogenic fusions play a role in normal hematopoiesis, we analyzed the role of Prdm16 in the biology of HSCs using Prdm16-deficient mice. We show here that, within the hematopoietic system, Prdm16 is expressed very selectively in the earliest stem and progenitor compartments, and, consistent with this expression pattern, is critical for the establishment and maintenance of the HSC pool during development and after transplantation. Prdm16 deletion enhances apoptosis and cycling of HSCs. Expression analysis revealed that Prdm16 regulates a remarkable number of genes that, based on knockout models, both enhance and suppress HSC function, and affect quiescence, cell cycling, renewal, differentiation, and apoptosis to various extents. These data suggest that Prdm16 may be a critical node in a network that contains negative and positive feedback loops and integrates HSC renewal, quiescence, apoptosis, and differentiation. (Blood. 2011;117(19):5057-5066) IntroductionHematopoietic stem cells (HSCs) can self-renew and differentiate into all cell types of the hematopoietic system and are regulated by interacting intrinsic and extrinsic mechanisms. 1 Among intrinsic mechanisms, several transcriptional regulators involved as partners of leukemogenic fusion proteins, such as Mll 2-4 and Evi1, 5 are required for normal HSC function, whereas others, such as Runx1 6,7 and Scl,8,9 are essential for the establishment of HSCs during development. PR domain-containing 16 (PRDM16), a 140-kDa zinc finger protein, was originally discovered as a fusion partner in t(1:3)(p36;q21) translocations in acute myeloblastic leukemia (AML) 10,11 and later in t(1;21)(p36;q22) translocations fused to RUNX1. 12,13 In addition, elevated PRDM16 expression, because of promoter hypomethylation, is frequently observed in karyotypically normal AML. 14 Deletion of the PR domain, which shows homology with a SET chromatin remodeling domain and is also present in EVI1, 10 appears important for the leukemogenic properties of human PRDM16. Translocations involving PRDM16 invariably delete the PR domain, 10-13 whereas PR-deleted Prdm16 causes AML in p53 Ϫ/Ϫ mice. 14 Furthermore, both Prdm16 and Evi1 are frequent targets of insertional mutagenesis in mice, causing deletion of the PR domain. 15 Overexpression of Prdm16 expands HSCs in vitro. However, these expanded HSCs cause a myeloproliferative disease after transplantation. 16 Prdm16 has also been shown to be critical for the development of brown adipose tissue in the mouse. PRDM16 is a transcriptional cofactor and interacts with the ligand-activated transcription factor peroxisome proliferatoractivated receptor-␥ and with CCAAT/enhancer-binding protein-␤. 17,18 Although its involvement in leukemic transloc...

Botox has been primarily used in cosmetic treatment for lines and wrinkles on the face, but the botulinum toxin that Botox is derived from has a long history of medically therapeutic uses. For nearly 13 years, until the introduction of Botox Cosmetic in 2002, the only FDAapproved uses of Botox were for crossed eyes (strabismus) and abnormal muscle spasms of the eyelids (blepharospasm). Since then botulinum A, and the seven other forms of the botulinum toxin, have been continuously researched and tested. Botox is a neurotoxin derived from bacterium clostridium botulinm. The toxin inhibits the release of acetylcholine (ACH), a neurotransmitter responsible for the activation of muscle contraction and glandular secretion, and its administration results in reduction of tone in the injected muscle. The use of Botox is a minimally invasive procedure and is showing quite promising results in management of muscle-generated dental diseases like Temporomandibular disorders, bruxism, clenching, masseter hypertrophy and used to treat functional or esthetic dental conditions like deep nasolabial folds, radial lip lines, high lip line and black triangles between teeth.Pranav Nayyar et al., BOTOX : Broadening the Horizon of Dentistry www.jcdr.net

We have observed over expression of PACS-1, a cytosolic sorting protein in primary cervical tumors. Absence of exonic mutations and overexpression at the RNA level suggested a transcriptional and/or post transcriptional regulation. UCSC genome browser analysis of PACS-1 mRNA revealed two 8 base target sequences at the 3’ terminus for hsa-miR-34a and hsa-miR-449a. Quantitative RT-PCR and northern blot studies showed reduced or loss of expression of the two miRNAs in cervical cancer cell lines and primary tumors indicating dysregulation of these two miRNAs in cervical cancer. Loss of PACS-1 with siRNA or exogenous expression of hsa-miR-34a or hsa-miR-449a in HeLa and SiHa cervical cancer cell lines resulted in DNA damage response (DDR), S-phase cell cycle arrest and reduction in cell growth. Furthermore, the siRNA studies showed that loss of PACS-1 expression was accompanied by increased nuclear γH2AX expression, K-382-p53 acetylation and genomic instability. PACS-1 re-expression through LNA-hsa-anti-miR-34a or 449a or PACS-1 cDNA transfection led to the reversal of DDR and restoration of cell growth. Release of cells post 24_h serum starvation showed PACS-1 nuclear localization at G1-S phase of the cell cycle. Our results therefore indicate that the loss of hsa-miR-34a and hsa-miR-449a expression in cervical cancer leads to overexpression of PACS-1 and suppression of DNA damage response resulting in the development of chemo-resistant tumors.

Endometrial biopsy samples derived from 393 patients with assorted gynecological complaints were investigated for mycobacterial infection. By employment of four different techniques, mycobacterial pathogens were detected irrespective of the nature/type of clinical complaint. Mycobacterium tuberculosis was the predominant pathogen detected among the samples investigated.Tuberculosis occurs worldwide and causes widespread morbidity and mortality. Pulmonary and extrapulmonary sites are known to be associated with Mycobacterium tuberculosis infection. In fact, it is well known that pulmonary tuberculosis patients go on to develop extrapulmonary tuberculosis. One such manifestation is the occurrence of female genital tuberculosis (FGTB). The spread of the pathogen to fallopian tubes, endometria, and ovaries, leading to a variety of clinical conditions, has been described previously (1,8,15). The present study was undertaken to detect mycobacterial infection in endometrial biopsy (EB) samples collected from patients registered in the gynecological outpatient department of the All India Institute of Medical Sciences, New Delhi, India.Three hundred ninety-three patients attending the obstetrics and gynecology outpatient department of the All India Institute of Medical Sciences were included in the study. Of these, 285 were infertility patients, 80 had menstrual dysfunction complaints, 17 had chronic lower abdominal or pelvic pain, and the remaining 11 were patients with complaints such as ovarian cyst, fibroid, prolapsed uterus, and postrecanalization. The EB samples were processed as described by Chakravorty et al. (3). Four methods were used to detect mycobacteria in the EB samples. The processed EB extracts were microscopically examined for acid-fast bacilli (AFB), processed for isolation of mycobacteria by inoculation on Lowenstein-Jensen medium, and processed for extraction of target DNA by nested PCR (N-PCR) (12). Culture results at the time of this writing were available for 262 samples. Two hundred ninety-five EB samples were processed for histopathological examination by hematoxylin and eosin staining. The N-PCR for the hupB DNA target was carried out as described previously (10). The N-PCR products were electrophoresed on 10% polyacrylamide gel and stained with ethidium bromide. The amplicon sizes for M. tuberculosis and Mycobacterium bovis were ϳ116 bp and 89 bp, respectively. Species-level identification of the isolates obtained was done by spoligotyping (9) and by standard biochemical tests (16). Randomly selected EB samples showing dual bands (116 and 89 bp) were cloned into the pGEMT vector by using a TA cloning kit (Promega). The clones were sequenced at the DNA sequencing facility, South Campus Delhi University, New Delhi, India.The detection and identification of M. tuberculosis and M. bovis in representative EB specimens are depicted in Fig. 1. N-PCR-amplified products equivalent to 116 bp were obtained for five of the seven samples (lanes 1 to 3, 7, and 8). These samples were considered to be infecte...

Ionizing radiation causes depletion of hematopoietic cells and enhances the risk of developing secondary hematopoietic malignancies. Vitamin E analog gamma-tocotrienol (GT3), which has anticancer properties, promotes postirradiation hematopoietic cell recovery by enhancing spleen colony-forming capacity, and provides protection against radiation-induced lethality in mice. However, the underlying molecular mechanism involved in GT3-mediated postirradiation survival is not clearly understood. Recent studies have shown that natural dietary products including vitamin E provide a benefit to biological systems by modulating microRNA (miR) expression. In this study, we show that GT3 differentially modulates the miR footprint in the spleen of irradiated mice compared to controls at early times (day 1), as well as later times (day 4 and 15) after total-body irradiation. We observed that miR expression was altered in a dose- and time-dependent manner in GT3-pretreated spleen tissues from total-body irradiated mice. GT3 appeared to affect the expression of a number of radiation-modulated miRs known to be involved in hematopoiesis and lymphogenesis. Moreover, GT3 pretreatment also suppressed the upregulation of radiation-induced p53, suggesting the function of GT3 in the prevention of radiation-induced damage to the spleen. In addition, we have shown that GT3 significantly reduced serum levels of Flt3L, a biomarker of radiation-induced bone marrow aplasia. Further in silico analyses of the effect of GT3 implied the association of p38 MAPK, ERK and insulin signaling pathways. Our study provides initial insight into the mechanism by which GT3 mediates protection of spleen after total-body irradiation.

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Background/Aims The varied prevalence of traumatic dental injuries (TDI) in primary teeth around the globe raises a serious knowledge gap in the available literature. The aim of this study was to evaluate the prevalence of TDI in primary teeth and also to evaluate the different factors associated with TDI in primary teeth. Materials and Methods Comprehensive searches were performed in PubMed, Embase, Google Scholar, and The Cochrane Central Register of Controlled Trials with predefined search criteria. The primary outcome was the prevalence of TDI in primary teeth, and the secondary outcomes were the factors associated with TDI in primary teeth. Qualitative analysis was done using the Newcastle‐Ottawa scale adapted for cross‐sectional studies. The random‐effect model was used for meta‐analysis, and meta‐regression analysis was done to evaluate the heterogeneity between the included studies. Meta‐analysis was done using the “meta” package of “R” language. The overall quality of evidence was assessed using GRADEpro GDT software. Results A total of 24 cross‐sectional studies met the inclusion criteria representing 4876 TDIs in 22 839 children aged between 0 and 6 years old. The overall prevalence of TDI in primary teeth was 24.2% (95% CI: 18.24‐31.43, P = 0, I2 = 99%). Falls contributed the highest number of TDI ‐ 59.3% (95% CI: 41.05‐76.40, P < .01, I2 = 98%) ‐ in primary teeth. The most common type of tooth fracture in primary teeth was an enamel fracture (61.9%), and prevalence of TDI in children with incompetent lip closure was 49.4%. Conclusion The prevalence of TDI in cross‐sectional studies of primary teeth was 24.2% with very low quality of evidence. Falls contributed the highest number of TDI in primary teeth, accounting for 59.3%. Children with incompetent lip closure have the highest prevalence (49.4%) of TDI in primary teeth.

showed that the sensitivity of N-PCR (61.5%) was greater than that of smear microscopy (38.4%). Determination to the species level is important from the viewpoint of determining the prevalence of these mycobacteria in a community and would influence strategies currently adopted for the prevention of tuberculosis.Tuberculosis (TB) is a chronic, systemic infectious disease caused by Mycobacterium tuberculosis. The most common clinical manifestation is pulmonary TB. The inhaled bacilli can localize in alternate sites, leading to extrapulmonary TB (EPTB). Among the different manifestations of EPTB, tuberculous meningitis (TBM) has been considered to be a fatal form (41). Fatality rates in developing countries have been reported to range from 44 to 69% (15,18,30). In fact, delayed or erroneous diagnosis often results in serious long-term debilitating complications. Central nervous system involvement has frequently been found secondary to TB elsewhere in the body, particularly the lungs. The presence of TB elsewhere in the body favors the diagnosis, although its absence does not exclude it. The great majority of patients with neuro-TB are diagnosed on the basis of clinical criteria, imaging, and laboratory investigation of the cerebrospinal fluid (CSF). The clinical response to antituberculosis therapy in all forms of neuro-TB is excellent, provided the diagnosis is made early, before an irreversible neurological defect occurs.Hence, precise and rapid clinical diagnosis of TBM is a critical component of the management of TBM patients (12,24,25). Culture and Ziehl-Neelsen staining of the CSF are specific but insensitive due to the paucity of bacilli. Nucleic acid amplification techniques have shown promising results in overcoming this drawback (20,22,30,42).M. tuberculosis is a member of the M. tuberculosis complex (MTC), which includes M. bovis, "M. MATERIALS AND METHODSPatients. CSF samples from 212 patients were investigated. The patient distribution was as follows. For the first part of the study, 112 patients admitted to the neurology ward of the All India Institute of Medical Sciences (AIIMS), New Delhi, were investigated. Subsequently, for the second part of the study, CSF samples from 100 children (Յ12 years old) admitted to the pediatric ward of Safdarjung Hospital, New Delhi, India, were investigated. The institutional ethical committee approved the study. At the time of data analysis, the AIIMS hospital records of the 69 patients were obtained. These 69 cases were separated into TBM and NTBM (nontubercular meningitis) groups on the basis of the criteria described by Ahuja et al. (1) (Table 1). CSF was collected under aseptic conditions by lumbar puncture. Five hundred microliters to 2.0 ml of CSF was available for the study. Samples were stored at Ϫ20°C, prior to processing for target DNA for N-PCR and smear microscopy for acid-fast bacilli (AFB; auramine O stain).Mycobacterial strains. M. tuberculosis H37Rv DNA was obtained from TB research material, National Institute of Allergy and Infectious Diseases, N...