The Implication of Nutrition on the Prevention and Improvement of Age-Related Sarcopenic Obesity: A Systematic Review

OBJECTIVES

Nutrition plays a pivotal role in the initiation and progression of sarcopenic obesity, making it a critical focus for preventing and treating this condition. However, the specific dietary components that effectively combat sarcopenic obesity remain poorly understood. The objective of this systematic review was to examine the potential nutritional and dietary factors that may play a role in the development of sarcopenic obesity in the elderly population.

METHODS

To identify relevant studies investigating the association/effects of dietary pattern/single foods/nutrients or supplements with sarcopenic obesity-related outcomes, a comprehensive literature search was conducted until April 2023. The search encompassed multiple databases including PubMed, Scopus, EMBASE, and Google Scholar. Two researchers performed rigorous assessments that included screening titles and abstracts, reviewing full-text studies, extracting data, and evaluating the quality of the studies. The Newcastle-Ottawa Scale was used for observational studies, while the Jadad-Oxford Scale was employed for clinical trials.

RESULTS

Twenty-three studies (14 observational studies and 9 trials) with 37078 participants, published between 2012 and 2022, were eligible for the systematic review. Of the 14 observational articles, two focused on dietary patterns and 12 on food/calorie/macro- and micronutrient intake. The nutritional interventions included the intake of supplements (i.e., protein, amino acids, tea catechin, and vitamin D) and dietary management (calorie restriction, very low-calorie ketogenic diet, and high-protein diet). Appropriate dietary factors, such as appropriate intake of calories, macronutrients, micronutrients, antioxidant nutrients, vegetables, fruits, and overall dietary quality, have been shown to be effective in preventing and treating sarcopenic obesity-related parameters. A combined approach of hypocaloric diet and high protein intake may be necessary for managing both obesity and sarcopenia in older individuals.

CONCLUSION

Studies suggest that dietary factors, such as overall dietary quality, appropriate intake of calories and protein, consumption of antioxidant nutrients, vegetables, fruits, and protein, may be linked to sarcopenic obesity.

Fatty acid composition, phytochemicals and antioxidant potential of Capparis spinosa sedes

The present study evaluates the contents in bioactive compounds, antioxidant activity, oil content and fatty acid composition of Capparis spinosa seeds. Samples were collected from 5 different habitats (AH: Ahar; KU: Kurdistan; U1, U2 and U3: Urmia) in Iran. The oil content in the seeds ranged from 16 to 27%. The predominant fatty acid was linoleic acid (45-50%) followed by oleic acid (30-39%), palmitic acid (2-8%) and stearic acid (2-3%). Total phenolic content (TPC) varied from 16.3 to 24.2 mg GAE/ g DW; total flavonoid content (TFC) ranged from 1.48 to 3.05 mg QE/g DW; and the antioxidant activity (DPPH assay) of the seeds was between 35 and 63%. The compounds obtained from different genotypes of C. spinosa seeds had different compositions, great antioxidant capacity and unsaturated fatty acids, and therefore could be a prospective source of natural bioactive molecules for the food and health industry.

Risk of thrombosis with thrombopoietin receptor agonists for ITP patients: a systematic review and meta-analysis

One possible side effect of thrombopoietin receptor agonists in immune thrombocytopenia is thrombosis. Our aim is to systematically review whether patients with ITP that were treated with a TPO-RA have an increased risk for thrombosis as compared to ITP patients without TPO-RA. Patients in the intervention group were required to receive TPO-RA therapy. The primary outcome was the incidence of thromboembolic events. Eleven studies were included in the pooled analysis. More thromboembolic events were noted in the TPO-RA group than in the control group: 25 compared to 4. Ten out of 11 studies showed a relative risk greater than 1. However, none of these individual risk ratios was statistically significant. The meta-analysis showed a RR of 1.82 [95% CI 0.78-4.24]. Our findings indicate there is a non-significant higher chance of thrombosis in ITP patients with TPO-RA treatments versus ITP patients without TPO-RA treatment.

Adalimumab-induced platelet antibodies resulting in severe thrombocytopenia

Anti-tumour necrosis factor-α (TNFα) agents are effective in diseases including Crohn's disease but may cause cytopenias. The mechanisms involved in anti-TNFα agent-induced thrombocytopenia are scarce. We report a 73-year-old male with Crohn's disease for which he currently used adalimumab, an anti-TNFα agent. He had received mesalazine and infliximab before the treatment of adalimumab. No comorbidities were present. Routine laboratory tests revealed a deep thrombocytopenia (thrombocytes 24 × 10⁹ /L), after which adalimumab was discontinued. Bleeding symptoms included cutaneous haematomas and mild epistaxis. Direct monoclonal antibody-specific immobilization of platelet antigens revealed autoantibodies specific to glycoprotein IIb/IIIa and glycoprotein V platelet receptors. There was no bone marrow suppression. Other causes of the thrombocytopenia were ruled out. The platelet count normalized after adalimumab discontinuation. No further interventions were required. Monitoring thrombocyte levels after initiating anti-TNFα agents is recommended, which could lead to prevention of this potentially fatal phenomenon.

Rifampin resistance among individuals with extrapulmonary tuberculosis: 4 years of experience from a reference laboratory

Information is limited about the drug resistance patterns in extrapulmonary tuberculosis (EPTB) in Iran. This study aimed to determine the prevalence of EPTB and to investigate the drug-resistance pattern in Mycobacterium tuberculosis strains collected from extrapulmonary samples at the Tehran regional TB reference laboratory. Extrapulmonary specimens from individuals with suspected TB referred to the TB reference laboratories in five cities of Iran were collected. Both standard conventional methods (culture and direct smear microscopy) and Xpert MTB/RIF assay were used for the identification of mycobacteria. Drug susceptibility testing was done using Xpert MTB/RIF. The proportion method on Lowenstein–Jensen medium was performed for confirmation. Between 2016 and 2020, a total of 12 050 clinical specimens from individuals with suspected TB were collected, of which 10 380 (86%) were pulmonary specimens and 1670 (14%) were extrapulmonary. Of the extrapulmonary specimens, 85 (5.0%) were positive for M. tuberculosis, and the remaining 1585 (95.0%) samples were negative by standard methods. Of 85 M. tuberculosis isolates, drug susceptibility testing was performed for 32 isolates, of which 1 (3.1%, 95% CI 0.0%–9.4%) was rifampin resistant and 31 (96.9%, 95% CI 90.1%–100%) were pan-susceptible. The rifampin-resistant isolate was also resistant to isoniazid, so was assigned as a multidrug-resistant TB. Our study indicated the frequency of drug-resistance among EPTB in Iran. Establishing rapid diagnostic methods for detection of drug-resistance in EPTB, performing drug susceptibility testing for all EPTB cases to provide effective treatment, and continuous monitoring of drug resistance, are suggested for prevention and control of drug resistance in EPTB in Iran.

Traditional and Dairy Products and Vegetables Dietary Patterns Are Inversely Associated with the Risk of Cataract in the Middle Age and Aged Population: A Case-Control Study

OBJECTIVES

Cataract is one of the most common causes of visual impairment and blindness in the world. In the present study, we have been trying to investigate the relationship between major dietary patterns and cataract.

DESIGN

This was a case-control study.

SETTING

An ophthalmology outpatient clinic of Khatam al-Anbia Hospital, in Shoushtar city.

PARTICIPANTS

336 subjects (168 patients with cataract and 168 healthy ones), from 40 to 80 years old, were recruited.

MEASUREMENTS

A socio-demographic questionnaire was used to record the demographic information. A food frequency questionnaire was used to determine the foods consumed during the last year. The principal component analysis was used to extract major dietary patterns. The possible relationship between the major dietary patterns and cataract was assessed by multivariable logistic regression models.

RESULTS

We tried to eliminate the effect of cofactors. The results showed "dairy products and vegetables" dietary pattern had a negative association with cataract (OR: 0.301, 95%CI =0.137-0.658, P trend =0.002). The fourth quartile of the "traditional" dietary pattern also showed a protective role against the cataract (OR: 0.393, 95%CI =0.184-0.842, P trend = 0.036). The third and fourth quartiles of "carbohydrate and simple sugar" pattern were more related with cataract compared to the first quartile (OR: 3.574, 95%CI =1.665-7.671, and OR: 5.067, 95%CI =2.265-11.335, P trend <0.001 respectively). No significant association was found between «nuts, seeds and simple sugar" dietary pattern and cataract.

CONCLUSION

It seems a dietary pattern rich in proteins and vegetables can decrease the risk of cataract in middle-aged and aged subjects.

Perioperative oral eltrombopag versus intravenous immunoglobulin in patients with immune thrombocytopenia: a non-inferiority, multicentre, randomised trial

BACKGROUND

Patients with immune thrombocytopenia are at risk of bleeding during surgery, and intravenous immunoglobulin is commonly used to increase the platelet count. We aimed to establish whether perioperative eltrombopag was non-inferior to intravenous immunoglobulin.

METHODS

We did a randomised, open-label trial in eight academic hospitals in Canada. Patients were aged at least 18 years, with primary or secondary immune thrombocytopenia and platelet counts less than 100 × 10⁹ cells per L before major surgery or less than 50 × 10⁹ cells per L before minor surgery. Previous intravenous immunoglobulin within 2 weeks or thrombopoietin receptor agonists within 4 weeks before randomisation were not permitted. Patients were randomly assigned to receive oral daily eltrombopag 50 mg from 21 days preoperatively to postoperative day 7 or intravenous immunoglobulin 1 g/kg or 2 g/kg 7 days before surgery. Eltrombopag dose adjustments were allowed weekly based on platelet counts. The randomisation sequence was generated by a computerised random number generator, concealed and stratified by centre and surgery type (major or minor). The central study statistician was masked to treatment allocation. The primary outcome was achievement of perioperative platelet count targets (90 × 10⁹ cells per L before major surgery or 45 × 10⁹ cells per L before minor surgery) without rescue treatment. We did intention-to-treat and per-protocol analyses using an absolute non-inferiority margin of -10%. This trial is registered with ClinicalTrials.gov, NCT01621204.

FINDINGS

Between June 5, 2013, and March 7, 2019, 92 patients with immune thrombocytopenia were screened, of whom 74 (80%) were randomly assigned: 38 to eltrombopag and 36 to intravenous immunoglobulin. Median follow-up was 50 days (IQR 49-55). By intention-to-treat analysis, perioperative platelet targets were achieved for 30 (79%) of 38 patients assigned to eltrombopag and 22 (61%) of 36 patients assigned to intravenous immunoglobulin (absolute risk difference 17·8%, one-sided lower limit of the 95% CI 0·4%; p_{non-inferiority}=0·005). In the per-protocol analysis, perioperative platelet targets were achieved for 29 (78%) of 37 patients in the eltrombopag group and 20 (63%) of 32 in the intravenous immunoglobulin group (absolute risk difference 15·9%, one-sided lower limit of the 95% CI -2·1%; p_{non-inferiority}=0·009). Two serious adverse events occurred in the eltrombopag group: one treatment-related pulmonary embolism and one vertigo. Five serious adverse events occurred in the intravenous immunoglobulin group (atrial fibrillation, pancreatitis, vulvar pain, chest tube malfunction and conversion to open splenectomy); all were related to complications of surgery. No treatment-related deaths occurred.

INTERPRETATION

Eltrombopag is an effective alternative to intravenous immunoglobulin for perioperative treatment of immune thrombocytopenia. However, treatment with eltrombopag might increase risk of thrombosis. The decision to choose one treatment over the other will depend on patient preference, resource limitations, cost, and individual risk profiles.

FUNDING

GlaxoSmithKline and Novartis.

Genotyping and drug susceptibility testing of Mycobacterium tuberculosis in Iran: a multi-centre study

Tuberculosis (TB) is a deadly infection and caused 1.4 million deaths in 2018. Assessing the geographic distribution of major lineages of Mycobacterium tuberculosis can contribute greatly to TB control. Mycobacterial interspersed repetitive unit variable number tandem repeat (MIRU-VNTR) typing is commonly used to differentiate various lineages of M. tuberculosis. A total of 2747 clinical specimens were collected consecutively from October 2018 through June 2019. Clinical isolates were identified as M. tuberculosis using standard biochemical tests. The standard 15-locus MIRU-VNTR typing was used for the genotyping of clinical isolates. Drug susceptibility testing was performed using the conventional proportion method. From the collected specimens, 100 were culture positive for M. tuberculosis. Using MIRU-VNTR, 99 different patterns were detected among the 100 isolates. They were distributed in one cluster comprising two strains and 98 unique patterns. Most of our isolates were similar to New-1 and Delhi/CAS strains. Of the M. tuberculosis isolates, 83 (83.0%) were pan-susceptible and 17 (17.0%) were resistant to at least one drug. Our study showed that MIRU-VNTR is a useful method for studying the genetic diversity of M. tuberculosis isolates in different regional settings and will help the health authorities to construct a preventive programme for TB.

Global, Regional, and National Levels and Trends in Burden of Oral Conditions from 1990 to 2017: A Systematic Analysis for the Global Burden of Disease 2017 Study

Government and nongovernmental organizations need national and global estimates on the descriptive epidemiology of common oral conditions for policy planning and evaluation. The aim of this component of the Global Burden of Disease study was to produce estimates on prevalence, incidence, and years lived with disability for oral conditions from 1990 to 2017 by sex, age, and countries. In addition, this study reports the global socioeconomic pattern in burden of oral conditions by the standard World Bank classification of economies as well as the Global Burden of Disease Socio-demographic Index. The findings show that oral conditions remain a substantial population health challenge. Globally, there were 3.5 billion cases (95% uncertainty interval [95% UI], 3.2 to 3.7 billion) of oral conditions, of which 2.3 billion (95% UI, 2.1 to 2.5 billion) had untreated caries in permanent teeth, 796 million (95% UI, 671 to 930 million) had severe periodontitis, 532 million (95% UI, 443 to 622 million) had untreated caries in deciduous teeth, 267 million (95% UI, 235 to 300 million) had total tooth loss, and 139 million (95% UI, 133 to 146 million) had other oral conditions in 2017. Several patterns emerged when the World Bank’s classification of economies and the Socio-demographic Index were used as indicators of economic development. In general, more economically developed countries have the lowest burden of untreated dental caries and severe periodontitis and the highest burden of total tooth loss. The findings offer an opportunity for policy makers to identify successful oral health strategies and strengthen them; introduce and monitor different approaches where oral diseases are increasing; plan integration of oral health in the agenda for prevention of noncommunicable diseases; and estimate the cost of providing universal coverage for dental care.

MicroRNA-221: biogenesis, function and signatures in human cancers

MicroRNAs are small non-coding RNAs of 18-25 nucleotides that regulate gene expression at the post-transcriptional level through binding to the 3´-UTR of mRNAs and block mRNA transcription or regulate its resistance. Increasing evidence indicates that dysregulation of miRNA is a hallmark of cancer. The miRNAs have an essential role in the regulation of oncogenes or tumor suppressor genes in cell signaling pathways. MiR-221 and miR-222 are two homologous microRNAs, the high expression levels of which have been commonly demonstrated in multiple human cancer types. The miR-221/miR-222 functions have been verified as oncogenes or tumor suppressors. Here, we reviewed the roles of miR-221/miR-222 in various kinds of cancer progression and development: controlling proliferative signaling pathways, avoiding cell deaths resulted from tumor suppressors, monitoring angiogenesis and even supporting epithelial-mesenchymal transition. We discussed that miR-221/miR-222 act as promising biomarkers for detection of human cancer types and suggested a new pathway for molecular targeted cancer therapy.

Peri-Operative Eltrombopag or Immune Globulin for Patients with Immune Thrombocytopaenia (The Bridging ITP Trial): Methods and Rationale

Background The Bridging ITP Trial is an open-label randomized trial designed to compare the oral thrombopoietin receptor agonist eltrombopag and intravenous immune globulin (IVIG) for patients with immune thrombocytopaenia (ITP) who require an increase in platelet count before elective surgery. Here, we report the study methods and rationale.

Methods We designed a multi-centre, non-inferiority randomized trial comparing daily oral eltrombopag starting 3 weeks pre-operatively, and IVIG administered 1 week pre-operatively for patients with ITP requiring a platelet count increase prior to surgery. Starting dose of eltrombopag is 50 mg daily with a weekly pre-operative dose titration schedule, and treatment is continued for 1 week after surgical haemostasis is achieved. IVIG is administered at a dose of 1 to 2 g/kg 1 week pre-operatively with the allowance for a second dose within 1 week after surgical haemostasis. The objective of the study is to demonstrate non-inferiority of eltrombopag for the primary endpoint of achieving the pre-operative platelet count threshold (50 × 109/L for minor surgery; or 100 × 109/L for major surgery) and sustaining platelet count levels above the threshold for 1 week after surgical haemostasis is achieved, without the use of rescue treatment. Secondary endpoints include thrombosis, bleeding and patient satisfaction.

Conclusion The Bridging ITP Trial will evaluate the efficacy and safety of eltrombopag as an alternative to IVIG in the peri-operative setting for patients with ITP. The protocol was designed to provide a management strategy that can be applied in clinical practice.

ClinicalTrials.gov Identifier NCT01621204.

High rates of nontuberculous mycobacteria isolation from patients with presumptive tuberculosis in Iran

Nontuberculous mycobacteria (NTM) can cause disease which can be indistinguishable from tuberculosis (TB), posing a diagnostic and therapeutic challenge, particularly in low- and middle-income settings. We aimed to investigate the mycobacterial agents associated with presumptive clinical pulmonary TB in Iran. A total of 410 mycobacterial isolates, obtained between March 2014 and January 2016, from 7600 clinical samples taken from consecutive cases of presumptive diagnosis of TB were identified. Phenotypic and molecular tests were used to identify the isolated organisms to the species level. Single-locus and multilocus sequence analysis based on 16S rRNA, rpoB, hsp65 and ITS locus were used to confirm the results. Of 410 consecutive strains isolated from suspected TB subjects, 62 isolates (15.1%) were identified as NTM. Patients with positive NTM cultures met American Thoracic Society diagnostic criteria for NTM disease. Mycobacterium simiae was the most frequently encountered (38.7%), followed by Mycobacterium fortuitum (19.3%), M. kansasii (17.7%) and M. avium complex (8.0%). Isolation of NTM, including M. simiae, from suspected TB cases is a serious public health problem and merits further attention by health authorities, physicians and microbiologists.

Association between Helicobacter pylori hopQI genotypes and human gastric cancer risk

The Helicobacter pylori use a number of mechanisms to survive in the stomach lumen and can lead to gastritis and reduction in stomach acid secretion. It has been found that the risk of developing gastric carcinoma is associated to heterogeneity of H. pylori virulence factors such as HopQ. The HopQ is one of the outer membrane proteins involved in bacterial adherence to gastric mucosa and has been suggested to also main role in the virulence of H. pylori. The purpose of the current study was to investigate the association between different H. pylori virulence hopQI (types I) genotyping and patients with gastroduodenal disorders. For this purpose 58 stomach biopsies of the patients with gastric cancer and 100 saliva samples from healthy and H. pylori infected individuals were collected and studied. Then genomic DNA was purified and PCR was done for desired gene via specific primers. The H. pylori infections were diagnosed using PCR for GlmM gene. Then frequencies of hopQI+ and hopQI- genotypes were determined in H. pylori infected cases. Statistical analysis showed that there were not significant differences between healthy and diseased ones for genotypes hopQI+ and hopQI-. Then the hopQI+ cannot be as a risk factor genotype for gastric cancer.

Built-up edge investigation in vibration drilling of Al2024-T6

Adding ultrasonic vibrations to drilling process results in an advanced hybrid machining process, entitled "vibration drilling". This study presents the design and fabrication of a vibration drilling tool by which both rotary and vibrating motions are applied to drill simultaneously. High frequency and low amplitude vibrations were generated by an ultrasonic transducer with frequency of 19.65 kHz. Ultrasonic transducer was controlled by a MPI ultrasonic generator with 3 kW power. The drilling tool and workpiece material were HSS two-flute twist drill and Al2024-T6, respectively. The aim of this study was investigating on the effect of ultrasonic vibrations on built-up edge, surface quality, chip morphology and wear mechanisms of drill edges. Therefore, these factors were studied in both vibration and ordinary drilling. Based on the achieved results, vibration drilling offers less built-up edge and better surface quality compared to ordinary drilling.

Cost analysis and safety comparison of Cisatracurium and Atracurium in patients undergoing general anesthesia

BACKGROUND

Non-depolarizing neuromuscular blocking agents (NMB) differ in pharmacokinetic and pharmacodynamic parameters. An anesthesiologist according to these similarities and differences is able to choose the least costly one if the same safety profile and same clinical benefit achieved with the different alternatives.

AIM

The main objective of this study is to evaluate the economic and adverse drug reactions prevalence and differences between cisatracurium and atracurium the two non-depolarizing NMB drugs, which are widely used in adult patients undergoing surgery with general anesthesia in a teaching Hospital in Iran.

MATERIALS AND METHODS

A cost analysis and adverse drug reactions (ADR) monitoring were performed. Only direct costs were considered and data were collected through a prospective randomized study. Regardless of the type of surgery, 100 patients were randomly divided into two equal groups to receive either cisatracurium or atracurium by anesthesiologists. ADRs prevalence and cost differences between patients receiving one of the two non-depolarizing NMB agents were evaluated by independent sample t-test and Chi-square test respectively.

RESULTS

No significant difference was observed between the two groups of patients in demographic data. There was no statistical difference in the ADR prevalence in both groups. The numbers of ADR within atracurium group was higher than cisatracurium group, but this distinction was not statistically significant (p > 0.05). It was significant difference in cost between the two neuromuscular blocking drugs (p < 0.05).

CONCLUSIONS

According to our study it seems that atracurium and cisatracurium had similar safety profile and atracurium had a cost benefit relative to cisatracurium in initial loading doses. In patients with instability in hemodynamic parameters the cisatracurium was the appropriate choice.  

A novel rat model for chemotherapy-induced alopecia

BACKGROUND

More than half of all people diagnosed with cancer receive chemotherapy, and approximately 65% of these develop chemotherapy-induced alopecia (CIA), a side-effect that can have considerable negative psychological repercussions. Currently, there are very few animal models available to study the mechanism and prevention of CIA.

AIM

To develop a clinically relevant adult rat model for CIA.

METHODS

We first tested whether neonatal pigmented Long-Evans (LE) rats developed alopecia in response to the chemotherapeutic agents etoposide and cyclophosphamide. We then determined whether the rats developed CIA as adults. In the latter experiment, rat dorsal hair was clipped during the early telogen stage to synchronize the hair cycle, and starting 15 days later, the rats were treated with etoposide for 3 days.

RESULTS

Neonatal LE pups developed CIA in response to etoposide and cyclophosphamide, similar to other murine models for CIA. Clipping of the hair shaft during early telogen resulted in synchronized anagen induction and subsequent alopecia after etoposide treatment in the clipped areas only. Hair follicles in the clipped areas had the typical chemotherapy-induced follicular dystrophy (dystrophic catagen). When the hair in the pigmented alopecic areas regrew, it had normal pigmentation.

CONCLUSIONS

A novel, pigmented adult rat model has been established for CIA. By hair-shaft clipping during early telogen, synchronized anagen entry was induced, which resulted in alopecia in response to chemotherapy. This is the first clinically relevant adult rat model for CIA, and will be a useful tool to test agents for the prevention and treatment of CIA.

Expression and characterization of Escherichia coli derived hepatitis C virus ARFP/F protein

Genome of the hepatitis C virus (HCV) contains a long open reading frame encoding a polyprotein that is cleaved into 10 proteins. Recently, a novel, so called "ARFP/F", or "core+1", protein, which is expressed through a ribosomal frame shift within the capsid-coding sequence, has been described. Herein, to produce and characterize a recombinant form of this protein, the DNA sequence corresponding to the ARFP/F protein (amino acid 11-161) was amplified using a frame-shifted forward primer exploiting the capsid sequence of the 1b-subtype as a template. The amplicon was cloned into the pET-24a vector and expressed in different Escherichia coli strains. The expressed protein (mostly as insoluble inclusion bodies) was purified under denaturing conditions on a nickel-nitrilotriacetic acid (Ni-NTA) affinity column in a single step with a yield of 5 mg/L of culture media. After refolding steps, characterization of expressed ARFP/F was performed by SDS-PAGE and Western blot assay using specific antibodies. Antigenic properties of the protein were verified by ELISA using HCV-infected human sera and by its ability for a strong and specific interaction with sera of mice immunized with the peptide encoding a dominant ARFP/F B-cell epitope. The antigenicity plot revealed 3 major antigenic domains in the first half of the ARFP/F sequence. Immunization of BALB/c mice with the ARFP/F protein elicited high titers of IgG indicating the relevance of produced protein for induction of a humoral response. In conclusion, possibility of ARFP/F expression with a high yield and immunogenic potency of this protein in a mouse model have been demonstrated.

Early spontaneous immortalization and loss of plasticity of rabbit bone marrow mesenchymal stem cells

OBJECTIVES

Bone marrow-derived mesenchymal stem cells (BM-MSC) have been widely used for cell therapy and tissue engineering purposes. However, there are still controversies concerning safety of application of these cells after in vitro expansion. Therefore, we aimed to investigate the characteristics of rabbit BM-MSC during long-term culture.

MATERIALS AND METHODS

In this study, we have examined growth kinetics, morphological changes, differentiation potential and chromosomal abnormalities, as well as tumour formation potential of rabbit BM-MSC in long-term culture.

RESULTS AND CONCLUSION

We found that shortly after isolation, proliferation rate of rabbit BM-MSC decreases until they enter a dormant phase. During this period of quiescence, the cells are large and multinucleate. After some weeks of dormancy we found that several small mononuclear cells originated from each large multinucleate cell. These newly formed cells proliferated rapidly but had inferior differentiation potential. Although they were immortal, they did not have the capability for tumour formation in soft agar assay or in nude mice. This is the first report of spontaneous, non-tumorigenic immortalization of BM-MSC in rabbits. The phenomenon raises more concern for meticulous monitoring and quality control for using rabbit BM-MSC in cell-based therapies and tissue engineering experiments.

Periodontal Disease and Tooth Loss as Risks for Cancer: A Systematic Review of the Literature

BACKGROUND

Periodontal disease is a chronic destructive disease which occurs in adults, young people, and children. Periodontal disease and periodontal pathogens have been associated with several systemic diseases and more recently, several studies have suggested the relationship between periodontal disease and cancer. Studies with adjustment for the effect of smoking exposure, have found significant positive associations with different cancer sites. This review has outlined recent epidemiologic researches pointing to a possible role for tooth loss and periodontal disease in carcinogenesis.

METHODS

In this review, articles were selected from PubMed between1995 and June 2010 including human. Amongst 5,984 articles identified from the electronic search, 17 articles were selected for a full-text reading based on the inclusion and the exclusion criteria.

RESULTS

Nine out of 10 case-control studies reported a significant increase in the risk of oral cancer in patients with periodontitis and one with no significant association. Among 6 studies examining esophageal cancer and periodontal disease, 5 studies found a significant association between them and one study failed to find a significant increased risk of cancer. Also amongst 5 studies which focused on upper gastrointestinal, gastric cancer, and periodontal disease, 4 studies found an increased risk of cancer while one study did not report any relationship. In lung cancer evaluations, 3 out of 4 studies showed some levels of association between lung cancer and periodontal disease but after adjustment for smoking, no relationship were found. Three cohort studies have evaluated overall cancer rates in periodontal patients; two of them found small but significant association between cancers and periodontal disease.

CONCLUSION

The results indicate that there is a possible link between cancer and severe periodontal disease after adjustment for smoking and drinking habits.

Comparison of the Intersurgical Solus laryngeal mask airway and the i-gel supralaryngeal device

Summary We compared the performance of the Intersurgical Solus laryngeal mask airway (LMA) with that of the i-gel in 120 patients of ASA physical status during general anaesthesia with respect to oropharyngeal leak pressure, peak airway pressure, airway manipulation, insertion time, fibreoptic view, ventilatory parameters, and peri-operative complications. After receiving a standardised induction of anaesthesia, either a Solus LMA (60 patients) or an i-gel (60 patients) was inserted. One hundred and fifteen patients completed the study. The leak pressure was significantly higher in the LMA group than the i-gel group (mean (SD) 22.7 (7.7) cmH(2)O vs 19.3 (7.1) cmH(2)O; p = 0.02). A better fibreoptic view of the larynx was obtained in patients in the LMA group (p = 0.02) compared to those in the i-gel group and less airway manipulation was required in the LMA group (p < 0.01). Both devices have good performance with very low peri-operative complications. However, the Solus LMA provides a better oropharyngeal seal, provides a better fibreoptic view, and requires less manipulation to secure the airway than the i-gel.

Do postsurgical interventions optimize ultimate scar cosmesis

Keloids and other scars are different manifestations of the normal wound healing process. If located in visible areas, scars may have a psychological impact that could affect the quality of life of the scar-bearing population. Good preoperatory planning including hiding incisions in natural anatomical landmarks or placing them parallel to relaxed skin tension lines are among the techniques used to improve the cosmesis of scars. Once a prominent or noticeable scar has developed, multiple therapeutic modalities can be applied including surgical excision, although high recurrence rates precludes its use as monotherapy. Several advanced surgical correction techniques including Z-plasty and W-plasty may be useful in repositioning scars. Other modalities that have been reported to improve scar cosmesis include cryosurgery, radiotherapy, lasers, and skin substitute grafts. Adjuvant postsurgical treatment modalities have reduced dramatically the recurrence rates associated with the removal of the scar. In this review of the literature the authors discuss evidence based data related to the abovementioned modalities and other topical and intralesional therapies including occlusion, compression, silicone, corticosteroids, interferons, imiquimod, resiquimod, tacrolimus, 5-fluorouracil, retinoids, as well as the role of several over-the-counter agents such as onion extract, vitamin E and the combination of hydrocortisone, vitamin E and silicone. Finally, they address newer modalities including vascular endothelial growth factor inhibitor, transforming growth factor-3, interleukin-10, mannose-6-phosphate, UVA-1, narrowband UVB, intense pulsed light and photodynamic therapy. Ultimately, the decision of choosing the most appropriate postexcisional management treatment should be taken by physicians on a case-by-case basis in order to obtain the best cosmetically acceptable results.

Molecular mimicry in inducing DNA damage between HIV-1 Vpr and the anticancer agent, cisplatin

The human immunodeficiency virus type 1 (HIV-1) viral protein R (vpr) gene is an evolutionarily conserved gene among the primate lentiviruses. Several functions are attributed to Vpr including the ability to cause cell death, cell cycle arrest, apoptosis and DNA damage. The Vpr domain responsible for DNA damage as well as the mechanism(s) through which Vpr induces this damage is unknown. Using site-directed mutagenesis, we identified the helical domain II within Vpr (aa 37-50) as the region responsible for causing DNA damage. Interestingly, Vpr Delta(37-50) failed to cause cell cycle arrest or apoptosis, to induce Ku70 or Ku80 and to suppress tumor growth, but maintained its capability to activate the HIV-1 LTR, to localize to the nucleus and to promote nonhomologous end-joining. In addition, our cytogenetic data indicated that helical domain II induced chromosomal aberrations, which mimicked those induced by cisplatin, an anticancer agent. This novel molecular mimicry function of Vpr might lead to its potential therapeutic use as a tumor suppressor.

Tumor necrosis factor-alpha gene promoter polymorphism in Iranian patients with chronic hepatitis B

BACKGROUND

Clearance of hepatitis B virus (HBV) infection requires a good host immune response. Cytokines like tumor necrosis factor-alpha (TNF- alpha) may play a role in such immune response. Genetic changes in TNF-a gene promoter region are known to influence TNF- alpha expression. We therefore studied the role of one such mutation in chronic HBV infection.

METHODS

Presence of -308 G/A polymorphism in the promoter region of TNF- alpha gene was looked for in 100 patients with chronic HBV infection, 91 subjects with spontaneously recovered HBV infection and 89 healthy controls, using a PCR-RFLP method.

RESULTS

Variant alleles (A/A or A/G) were found in 22 of 100 (22%) patients with chronic HBV infection, 21 of 91 (23%) subjects with spontaneous HBV clearance and 14 of 89 (15.7%) control subjects (p=ns for inter-group comparisons).

CONCLUSION

TNF- alpha promoter polymorphism -308A is common in Iranian population, but has no association with development of chronic HBV infection.

p27(SJ), a novel protein in St John's Wort, that suppresses expression of HIV-1 genome

Transcription of the HIV-1 genome is controlled by the cooperation of viral regulatory proteins and several host factors which bind to specific DNA sequences within the viral promoter spanning the long terminal repeat, (LTR). Here, we describe the identification of a novel protein, p27(SJ), present in a laboratory callus culture of Hypericum perforatum (St John's Wort) that suppresses transcription of the HIV-1 genome in several human cell types including primary culture of microglia and astrocytes. p27(SJ) associates with C/EBPbeta, a transcription factor that regulates expression of the HIV-1 genome in macrophages and monocytic cells, and the viral transactivator, Tat. The association of p27(SJ) with C/EBPbeta and Tat alters their subcellular localization, causing their accumulation in the perinuclear cytoplasmic compartment of the cells. Fusion of a nuclear localization signal to p27(SJ) forces its entry into the nucleus and diminishes the capacity of p27(SJ) to suppress Tat activity, but does not alter its ability to suppress C/EBPbeta activation of the LTR. Results from binding assays showed the inhibitory effect of p27(SJ) on C/EBPbeta interaction with DNA. Finally, our results demonstrate that expression of p27(SJ) decreases the level of viral replication in HIV-1-infected cells. These observations suggest the potential for the development of a therapeutic advance based on p27(SJ) protein to control HIV-1 transcription and replication in cells associated with HIV-1 infection in the brain.

p73 modulates HIV-1 Tat transcriptional and apoptotic activities in human astrocytes

HIV-1 Tat is a potent transcriptional activator of the viral promoter with the ability to modulate a number of cellular regulatory circuits including apoptosis. Tat exerts its effects through interaction with viral as well as cellular proteins. Here, we studied the influence of p73, a protein that is implicated in apoptosis and cell cycle control, on Tat apoptotic function in the central nervous system. We recently demonstrated the ability of Tat to associate with p73, and that this association modulates Tat transcriptional activity (Amini et al., Mol Cell Biol 2005; 18: 8126-8138). We demonstrated that p73 interferes with Tat-mediated apoptosis by preventing the up-regulation of Bax and down-regulation of Bcl-2 proteins in astrocytes. Thus, the interplay between Tat and p73 may affect Tat contribution to apoptotic events in the brain, limiting its involvement in the neuropathology often observed in the brains of HIV-1 patients.

The Thoracic Surgical Patient: Initial Postoperative Care

Thoracic surgery patients require complex perioperative care. Accurate preoperative screening of pulmonary conditions can only partially predict the requirement of postoperative mechanical ventilation. In general, extensive lung resections are associated with significant gas exchange abnormalities. In this group of patients, a mechanical ventilation strategy protective from barotrauma and volutrauma and a conservative use of intraoperative and postoperative fluid limit the inevitable increase of extravascular lung water and gas exchange impairment. A wise use of pulmonary vasodilatatory and bronchodilating drugs and airway manipulation including suctioning and bronchoscopy can also significantly affect postoperative respiratory dysfunction and hospital stay. A number of acute postoperative complications have been described specifically related to the type of surgery or pleural space suctioning devices. The role of the intensivist is to maintain a low index of suspicion for such complications, when acute hemodynamic or pulmonary deterioration occurs and be prepared to immediately correct them or alert the thoracic surgeon. In general, when these roles are observed, thoracic surgery can be safely performed with a low perioperative mortality.

Functional interaction between cyclin T1/cdk9 and Puralpha determines the level of TNFalpha promoter activation by Tat in glial cells

In addition to its stimulatory effect on transcription of the HIV-1 LTR, the early protein of HIV-1, Tat, exhibits detrimental effects on the CNS by deregulating the expression of several cytokines and immunomodulators including TNFalpha. Activation of the viral promoter by Tat requires several cellular proteins including cyclin T1 and its partner, cdk9, which upon association with the TAR sequence of the LTR, forms a complex that enhances the activity of RNA polymerase II. Here, we examined the involvement of cyclin T1/cdk9 in Tat-mediated transcriptional activation of the TNFalpha promoter which has no TAR sequence. Results from transfection of human astrocytic cells revealed that both cyclin T1 and cdk9 stimulate the basal promoter activity of TNFalpha, although the level of such activation is decreased in the presence of Tat. Ectopic expression of Puralpha, a brain-derived regulatory protein which binds to Tat, enhanced the basal level of TNFalpha transcription, yet exerted a negative effect on the level of Tat activation of the TNFalpha promoter. The antagonistic effect of Puralpha and Tat upon the TNFalpha promoter was diminished in the presence of cyclin T1 and cdk9, suggesting cooperativity of Puralpha with cyclin T1 and cdk9 in Tat activation of the TNFalpha promoter. Results from protein-protein binding studies showed the interaction of Puralpha with both cyclin T1 and cdk9 through distinct domains of Puralpha which are in juxtaposition with each other. Interestingly, the site for cyclin T1 binding within Puralpha is adjacent to the region which is important for Tat/Puralpha association. In light of these observations, we propose a model which ascribes a bridging role for Puralpha in assembling Tat, cyclin T1, and cdk9 around the promoter region of TAR-negative genes such as TNFalpha, which is responsive to Tat activation.

Factors associated with fetal growth and body composition as measured by ultrasound

OBJECTIVE

This study seeks to determine which parental demographic and metabolic factors best correlate with fetal growth and body composition as estimated by ultrasound.

STUDY DESIGN

Thirty-one gravid patients had ultrasound estimates of fetal anthropometry in mid-third trimester. These measurements included estimated fetal weight, abdominal subcutaneous fat, and/or thigh subcutaneous fat thickness. Independent variables included diagnosis of gestational diabetes, parental demographic factors, neonatal sex, and late gestation estimates of carbohydrate metabolism.

RESULTS

In the multivariate stepwise model the strongest predictor of ultrasound estimated fetal weight was basal hepatic glucose production, followed by late gestation insulin sensitivity (total R (2) = 0.27). The strongest predictors of abdominal subcutaneous fat thickness were weight gain and presence of gestational diabetes (total R (2) = 0.25).

CONCLUSION

Measures of maternal carbohydrate metabolism, rather than fat mass, explain sonographic measurements of fetal weight. We speculate that factors other than maternal carbohydrate metabolism further explain the variances of fetal adiposity.

CNS invasion by CD14+/CD16+ peripheral blood-derived monocytes in HIV dementia: perivascular accumulation and reservoir of HIV infection

Increases in circulating CD14+/CD16+ monocytes have been associated with HIV dementia; trafficking of these cells into the CNS has been proposed to play an important role in the pathogenesis of HIV-induced neurological disorders. This model suggests that events outside the CNS leading to monocyte activation initiate the process leading to HIV dementia. To investigate the role of this activated monocyte subset in the pathogenesis of HIV dementia, we examined brain specimens from patients with HIV encephalopathy (HIVE), HIV without encephalopathy, and seronegative controls. An accumulation of perivascular macrophages was observed in HIVE. The majority of these cells identified in microglial nodules and in the perivascular infiltrate were CD14+/CD16+. P24 antigen colocalized with both CD14 and CD16 suggesting that the CD14+/CD16+ macrophage is a major reservoir of HIV-1 infection in CNS. Using CD45/LCA staining, the perivascular macrophage was distinguished from resident microglia. In addition to perivascular and nodular localizations, CD16 also stained ramified cells throughout the white matter. These cells were more ramified and abundant than cells positive for CD14 in white matter. Double staining for p24 and CD16 suggests that these cells were often infected with HIV-1. The prominent distribution of CD14+ cells in HIVE prompted our analysis of soluble CD14 levels in cerebrospinal fluid. Higher levels of soluble CD14 (sCD14) were observed in patients with moderate-to-severe HIV dementia, suggesting the utility of sCD14 as a surrogate marker. CD14+/CD16+ monocytes may play a role in other neurological disorders and sCD14 may be useful for evaluating these conditions.

Cell cycle regulation of NF-kappa b-binding activity in cells from human glioblastomas

Glioblastoma multiforme is a highly malignant and anaplastic tumor of the central nervous system representing more than 50% of all malignant gliomas. The cell origin of this highly undifferentiated tumor remains obscure, although it is postulated that glioblastomas are developed from astrocytes. The rapid growth of the glioma and the state of its undifferentiation are attributed to the deregulation of several signal transduction pathways and cell cycle events. Recent studies showed diverse functions for the NF-kappa B/Rel family of inducible transcription factors including differentiation, apoptosis, oncogenesis, and cell cycle regulation. We sought to examine the level of NF-kappa B activity throughout the glioma's cell cycle. Results from band-shift studies indicated a biphasic NF-kappa B DNA-binding activity in the nuclei of cycling glioblastoma cells. We showed that NF-kappa B-binding activity maximizes in nuclear extracts at specific cell cycle stages including G0/G1, mid-late G1, and S phase. Results from Northern blotting studies revealed that the differential expression of the NF-kappa B subunits, p50 and p65, may not be responsible for cell cycle stage-specific association of NF-kappa B subunits with DNA. However, results from Western blotting analysis utilizing nuclear extracts from glioma cells throughout the cell cycle demonstrated that the nuclear accumulation of p50 and p65 perfectly correlates with their DNA-binding activity. These observations suggest that the nuclear translocation of the p50/p65 subunit of NF-kappa B in glioma cells is cell cycle stage-dependent and that is distinct from the differential mRNA expression of these genes during glioma cell cycling. The possible role of NF-kappa B in glioma cell formation and regulation of cellular genes by NF-kappa B in these tumor cells is discussed.

Regulation of Puralpha gene transcription: evidence for autoregulation of Puralpha promoter

The single-stranded DNA and RNA binding protein, Puralpha, has recently received special attention as this protein, by associating with the specific nucleotide sequence (GGN repeats) and/or several important cellular and viral proteins regulates crucial biological events such as transcription, replication, and cell proliferation. In this study, we focused on the promoter activity of the Puralpha upstream DNA sequence and demonstrated that the sequence spanning 6,000 nucleotides upstream of the Puralpha transcription start site has promoter activity in various cell types. Results from promoter deletion studies revealed that this region encompasses various regulatory motifs which differentially participate in the promoter activity of Puralpha in various cells. The transcription start site of Puralpha is surrounded by the GA/GC-rich sequence which exhibits the ability to interact with Puralpha, suggesting a role for autoregulation of Puralpha transcription. Results from co-transfection studies revealed that ectopic expression of Puralpha reduced transcriptional activity of the Puralpha promoter and the region located between amino acid residues, 1-85 of Puralpha is important for the observed autoregulatory event. The regulatory protein of the human neurotropic virus, JCV, T-antigen, which interacts with Puralpha, decreased transcriptional activity of the Puralpha promoter. Co-expression of JCV T-antigen and Puralpha had no significant effect on the suppression of Puralpha gene transcription by either protein. The importance of this finding in light of earlier results showing down regulation of Puralpha during JCV infection of glial cells is discussed.

Cooperative interaction between HIV-1 regulatory proteins Tat and Vpr modulates transcription of the viral genome

The virion-associated protein of human immunodeficiency virus, type 1 (HIV-1), Vpr, is a small protein with 96 amino acid residues that has the ability to modulate transcription of HIV-1 long terminal repeat (LTR) promoter activity and affects several cellular functions. In this study we have employed molecular approaches to further investigate the mechanism by which Vpr exerts its regulatory effect upon the LTR. We show that by structural and functional interaction with Tat, a potent viral regulatory protein, Vpr synergistically enhances the transcriptional activity of the HIV-1 LTR. Because Tat utilizes cyclin T1 and its partner, CDK9 to elevate the level of transcription from the LTR, we examined the cooperativity between Vpr, Tat, and cyclin T1/CDK9 on viral gene transcription. Results from co-transfection studies indicated superactivation of LTR by Tat and cyclin T1/CDK9 in the presence of wild type Vpr. This activation was not observed with the R73S mutant of Vpr, which contains arginine to serine transition at residue 73. Interestingly, expression of R73S mutant in cells exerts a negative effect on the observed superactivation of the LTR by Tat, cyclin T1/CDK9, and wild type Vpr. Results from protein-protein interaction studies indicated that Vpr is associated with both Tat and cyclin T1 in cells expressing these proteins. Use of deletion mutant proteins in binding studies revealed that the binding sites for Tat and Vpr within cyclin T1 are distinct and that association of these two viral proteins with cyclin T1 is independent from each other. These observations suggest a working model on the cooperative interaction of Vpr with viral and cellular proteins and its involvement in control of viral gene transcription and replication. Moreover identification of R73S mutant of Vpr provides a new therapeutic avenue for controlling HIV-1 gene transcription and replication in the infected cells.

Antigen-specific production of RANTES, macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta in vitro is a correlate of reduced human immunodeficiency virus burden in vivo

RANTES (regulated on activation, normal T expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta are human immunodeficiency virus (HIV) suppressor factors by virtue of their ability to compete with HIV for access to cell surface R5. Their ability to block HIV infection in vitro is unequivocal; however, their role as HIV suppressor factors in vivo is not firmly established. We therefore conducted a study to test the hypothesis that production of these factors in vitro was a correlate of decreased virus burden in vivo. Moreover, we asked whether higher beta chemokine production could be demonstrated with cells from people who are R5D32 heterozygotes, compared with people who are R5 wild-type homozygotes. Our data support the thesis that RANTES, MIP-1alpha, and MIP-1beta production is associated with decreased in vivo virus load. Moreover, enhanced production of these factors may be explained in part by the genetic background of the host.

Detection of HIV-1 Tat and JCV capsid protein, VP1, in AIDS brain with progressive multifocal leukoencephalopathy

HIV-1 infection can lead to severe central nervous system (CNS) clinical syndromes in more than 50% of HIV-1 positive individuals. Progressive multifocal leukoencephalopathy (PML) is the frequent opportunistic infection of the CNS which is seen in as high as 5% of AIDS patients. Results from previous cell culture studies showed that the HIV-1 regulatory protein, Tat can potentiate transcription of the human neurotropic virus, JCV, the causative agent for PML in cells derived from the human CNS. In this communication we examine the presence of the HIV-1 regulatory protein, Tat, as well as the HIV-1 and JCV structural proteins, p24 and VP1, respectively in AIDS/PML clinical samples. We demonstrate high level expression of the JCV capsid protein, VP1, in oligodendrocytes and to some degree in astrocytes of AIDS with PML. In HIV-1+ samples expression of HIV-1 core protein, p24 was detected in perivascular monocytic cells and to a lesser extent in astrocytes and endothelial cells. A lack of p24 expression in oligodendrocytes suggested no infection of these cells with HIV-1. Interestingly, HIV-1 Tat was detected in various infected cells as well as in uninfected oligodendrocytes from HIV-1+ tissue, supporting the earlier in vitro findings that secreted Tat from the infected cells can be localized in the neighboring uninfected cells. The presence of Tat in oligodendrocytes was particularly interesting as this protein can up-modulate JCV gene transcription and several key cell cycle regulatory proteins including cyclin E, Cdk2, and pRb. The data presented here provide in vivo evidence for a role of HIV-1 Tat in the pathogenesis of AIDS/PML by acting as a positive regulatory protein that affects the expression of JCV and other cell regulatory proteins in the CNS.

Transdominant activity of human immunodeficiency virus type 1 Vpr with a mutation at residue R73

The 96-amino-acid-long human immunodeficiency virus type 1 virion-encoded accessory protein Vpr is of particular interest, as this protein, which is found in association with viral particles, can exert a regulatory effect on both virus replication and host cell function. Evidently, Vpr, through interaction with several host regulatory proteins, can modulate transcription from the viral long terminal repeat promoter. Expression of Vpr in cells results in deregulation of cell proliferation during the cell cycle pathway at the G(2) stage. Vpr has unique structural features consisting of multiple functional domains. In this study, we have focused on the leucine/isoleucine-rich domain near the carboxyl terminus of Vpr at residue 73 (arginine) and have demonstrated that alterations at this residue result in ablation of transcriptional activity of Vpr and its ability to block cell cycle events at the G(2) stage. Interestingly, substitution mutations at R73 have resulted in a peptide with dominant negative activities on wild-type functions in transcription and host proliferation events. Results from in vitro and in vivo protein-protein interaction studies have revealed that functionally inactive mutant Vpr can be associated with wild-type protein, presumably through the N-terminal regions of the protein which have been shown to be important for Vpr oligomerization. Thus, it is likely that complexation of the mutant Vpr with wild-type protein functionally inactivates Vpr. The importance of these findings in light of the development of therapeutic strategies is discussed.