Photodynamic Therapy in Oral Cancer: A Narrative Review.

Methods: A comprehensive search in PubMed, Scopus, and Google Scholar was performed using relevant keywords to structure this narrative review. Only English articles were included and assessed according to titles, abstracts, and full texts. Background: Photodynamic therapy (PDT) is applied for targeting pre-malignancy and malignancies in the head and neck, skin, lungs, and gastrointestinal tract and has been greatly promising in reducing disfigurement and morbidity. This method includes a light-sensitive medicine known as a photosensitizer and a light source used through a minimally invasive surgical tool. Objective: This study aimed to review the application of PDT in managing head and neck cancers (HNCs) and provide an overview of the most recent advances in PDT and its efficiency in increasing the long-term life quality of patients with HNC. Results: The light source irradiates light at an appropriate wavelength that can be absorbed by the sensitizer and produce cytotoxic free radicals that can kill tumor cells, impair microvasculature in the tumor microenvironment, and stimulate further inflammatory responses of the immune system. Patients with either early lesions or advanced disease conveniently accept to receive PDT in outpatient clinics. Therefore, this simple technique is considered a novel and promising approach that can be used either individually or in association with other methods. However, its application as a management method in oral malignancies has yet to be studied. PDT is also suggested as a promising adjuvant treatment with better functional results. Then, it is possible to conclude that PDT's effectiveness in treating various tumors has been shown to depend on the depth of the lesion location. Its safety is acceptable, but its limited irradiation depth confines its application in the advanced stages of cancer. Conclusions: PDT is critically applicable in the early diagnosed cancers and superficial tumors where many heads and neck lesions settle as an ideal candidate for PDT because of the possibility of accurate evaluation of lesions and providing appropriate irradiation at these sites.

Antimicrobial Peptides: Features, Action, and Their Resistance Mechanisms in Bacteria.

In recent years, because of increased resistance to conventional antimicrobials, many researchers have started to study the synthesis of new antibiotics to control the disease-causing effects of infectious pathogens. Antimicrobial peptides (AMPs) are among the newest antibiotics; these peptides are integral compounds in all kinds of organisms and play a significant role in microbial ecology, and critically contribute to the innate immunity of organisms by destroying invading microorganisms. Moreover, AMPs may encourage cells to produce chemokines, stimulate angiogenesis, accelerate wound healing, and influence programmed cell death in multicellular organisms. Bacteria differ in their inherent susceptibility and resistance mechanisms to these peptides when responding to the antimicrobial effects of AMPs. Generally, the development of AMP resistance mechanisms is driven by direct competition between bacterial species, and host and pathogen interactions. Several studies have shown diverse mechanisms of bacterial resistance to AMPs, for example, some bacteria produce proteases and trapping proteins; some modify cell surface charge, change membrane fluidity, and activate efflux pumps; and some species make use of biofilms and exopolymers, and develop sensing systems by selective gene expression. A closer understanding of bacterial resistance mechanisms may help in developing novel therapeutic approaches for the treatment of infections caused by pathogenic organisms that are successful in developing extensive resistance to AMPs. Based on these observations, this review discusses the properties of AMPs, their targeting mechanisms, and bacterial resistance mechanisms against AMPs.

Anti-cancer Effects of Metformin: Recent Evidences for its Role in Prevention and Treatment of Cancer.

BACKGROUND: Metformin is widely used for management of Type 2 Diabetes Mellitus (T2DM). Recently growing evidences have shown its anti-cancer effects. The results are mainly from observational studies and thus few information is available concerning the mechanisms of action. METHOD: This paper reviews recent available evidences for anti-cancer effects of metformin. The effects of metformin in specific cancers including colorectal, prostate, pancreatic, renal, cervical, endometrial, gastric, lung, breast, and ovarian cancer are reviewed. RESULTS: Adenosine Monophosphate (AMP)-Activated Protein Kinase (AMPK) plays an important role in mechanism of action of metformin. The anti-cancer mechanisms of metformin include direct and indirect effects. The direct effects of metformin include AMPK-independent and AMPK-dependent effects whereas decrease in glucose level, hyperinsulinemia, and Insulin-like Growth Factor 1 (IGF-1) level are considered its indirect effects. Metformin also decreases both pro-inflammatory cytokines and Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF- κB) and improves the immune response to cancer cells. CONCLUSION: Although the results of recent trials confirm the efficacy of metformin in prevention and treatment of different cancers, the evidences are not adequate enough.

Cirrhosis induced by bile duct ligation alleviates acetic acid intestinal damages in rats: Involvements of nitrergic and opioidergic systems.

BACKGROUND: Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats. METHODS: Colitis was induced by acetic acid 28days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3days after induction. RESULTS: Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10mg/kg), naltrexone (10mg/kg) and co-administration of L-NAME (1mg/kg) and naltrexone (5mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1mg/kg) + naltrexone (5mg/kg). CONCLUSION: Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.

Foeniculum vulgare essential oil ameliorates acetic acid-induced colitis in rats through the inhibition of NF-kB pathway.

AIM: The aim of the present study is to investigate the protective effects of Foeniculum vulgare essential oil on intestinal inflammation through the inhibition of NF-kB pathway in acetic acid-induced rat colitis. METHODS: Acute colitis was induced by intra-rectal administration of 2 mL of diluted acetic acid (4%) solution. Two hours after the induction of colitis, 0.2% tween 80 in normal saline, dexamethasone (2 mg/kg) and F. vulgare essential oil (100, 200, 400 mg/kg) were administered to the animals by oral gavage and continued for 5 consecutive days. Assessment of macroscopic and microscopic lesions was done. MPO activity was evaluated by biochemical method. Furthermore, TNF-α activity was detected by immunohistochemistry (IHC) and the expression level of p-NF-kB p65 protein was measured by western blot analysis. RESULTS: Dexamethasone and F. vulgare essential oil (200, 400 mg/kg) reduced the macroscopic and microscopic lesions compared to the acetic acid group (p < 0.01, p < 0.001). In addition, these agents decreased the activity of MPO (p < 0.01, p < 0.001) and the expression of TNF-α positive cells (p < 0.05, p < 0.01, p < 0.001) in the colon tissue compared to acetic acid group. Furthermore, they inhibited acetic acid-induced expression of p-NF-kB p65 protein (p < 0.05, p < 0.001). CONCLUSION: It is proposed that the anti-inflammatory activity of F. vulgare essential oil on acetic acid-induced colitis in rats may involve the inhibition of NF-kB pathway.

Challenges Related to Glycemic Control in Type 2 Diabetes Mellitus Patients.

Diabetes mellitus (DM) is a chronic disease with long-term complications. Glycemic control is an important part in management of DM. The first line in treatment of type 2 DM (T2DM) is diet and life style change. Metformin is the first choice of medication in T2DM patients. Sulfonylureas have high risk of hypoglycemia. Glinides are associated with lower risk of hypoglycemia in comparison to sulfonylureas. Also, α-glucosidase inhibitors decrease the polysaccharides' digestion in small intestine and are less effective in comparison to metformin and sulfonylureas in lowering hemoglobin A1c (HbA1c). These have no risk for hypoglycemia, but gastrointestinal symptoms are common. Thiazolidinediones are known as insulin sensitizers and are effective for a longer duration in comparison to sulfonylureas, however, have side effects such as fluid retention, edema and heart failure. Incretin mimetics including exenatide and liraglutide act through increase in insulin secretion by pancreatic beta cells, in a glucose-dependent manner. Therefore, these are associated with no risk of hypoglycemia. Pramlintide is an amylin agonist which is also effective in lowering postprandial blood glucose. Sitagliptin and vildagliptin are dipeptidyl peptidase-4 inhibitors and have no risk of hypoglycemia when used as monotherapy. Canagliflozin and dapagliflozin decrease blood glucose level by increasing urinary glucose excretion and are associated with weight loss.

A review on strategies for decreasing E. coli O157:H7 risk in animals.

Enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 is a food-borne pathogen that younger children are most prone to this microorganism. Hemolytic Uremic Syndrome (HUS) caused by EHEC, leads to the destruction of red blood cells and kidney failure. The virulence of E.coli O157:H7 is attributed to fimbriae, that facilitate colonization of bacteria within the colon and verotoxins (VT) or Shiga toxins (Stx) that are released into the blood. Although, in most cases, the infection is self-limitedin young children and aged population, it may cause HUS. Therefore, several investigations are performed in order to offer effective therapies and vaccines, which can prevent and treat the infection in appropriate time. As the pathogenesis of this infection is complicated, a multi-targeted strategy is required. Since cattle are the most important reservoir of EHEC and the root of contamination, reducing E. coli O157:H7 at the farm level should decrease the risk of human illness. Several vaccine approaches have been employed with different proper outcomes in animal models, including recombinant proteins (virulence factors such as; Stx1/2, intimin, EspA, fusion proteins of A and B Stx subunits), avirulent ghost cells of EHEC O157:H7, live attenuated bacteria expressing recombinant proteins, recombinant fimbrial proteins. In addition to protein-based vaccines, DNA vaccines have provided proper prevention in the laboratory animal model. This review paper summarizes the previous studies, current status and future perspective of different immunization strategies for eradicating Enterohemorrhagic Escherichia coli O157:H7.

Psychopharmacology of Attention-Deficit Hyperactivity Disorder: Effects and Side Effects.

Attention-deficit hyperactivity disorder (ADHD) is a common psychiatric disorder in children which manifests with hyperactivity, impulsivity, and/or inattention. Several drugs are used in treatment of ADHD. Stimulants, atomoxetine, anti-depressants, and bupropion are common medications used in the treatment of ADHD. Stimulants are widely used as the first line treatment in children with ADHD. Their mechanism of action is the release of dopamine and norepinephrine in central nervous system. Methylphenidate is the most common stimulant used for the treatment of ADHD. Methylphenidate significantly reduces ADHD symptoms in children both at home and school and improves their social skills. Methylphenidate is safe in healthy children and has shown to have no cardiac side effects in these patients. Other medications include: Atomoxetine, Amphetamines, Clonidine, Melatonin, and anti-depressants. Effects, side effects, and mechanism of action these drugs have been discussed in this paper.

Congenital Cutis Laxa Type 2 Associated With Recurrent Aspiration Pneumonia and Growth Delay: Case Report.

Cutis laxa is a connective tissue disorder caused by deficiency of fibro elastic plexus, which can involve multiple organs. It is inherited in autosomal dominant, autosomal recessive, and X-linked. Autosomal recessive cutis laxa type 2, which appears to compromise a spectrum of disorders, starts with severe wrinkly skin syndrome and leads to more severe diseases related to growth and developmental delays and skeletal anomalies. The clinical manifestations in some of cases of Cutis laxa consist of redundant loose skin, pre-and post-natal growth deficiency, mental retardation, large fontanels, and dislocation of the hips. The authors present the case of a female patient with involved internal organ disorder and delay in growth in addition to skin laxity in which gene sequence analysis of PYCR1 indicated C.797G>A mutation.

Prevalence of and Factors Associated with Migraine in Medical Students at BandarAbbas, Southern Iran, in 2012.

BACKGROUND: Migraine is one of the most common etiologies for headache. This very common neurological disorder has a significant impact on patients' quality of life. The aim of the current study is to evaluate the prevalence of migraine among medical students in the Hormozgan University of Medical Sciences (HUMS). METHODS: A total of 350 medical students were enrolled in our descriptive study. Data were collected using the standard questionnaire of the International Headache Association. The data were analyzed by SPSS 20.0 software using descriptive statistics, Chi-Square, and Independent Samples T-Test. A P-value of ≥0.05 was considered statistically significant, since most public health professionals use this value as a standard. RESULTS: Among the medical students in our study, 24.6% had experienced frequent, severe headaches. The underlying causes of the headaches were diagnosed in 19.8% of the students. The prevalence of migraine in our study was 16.3% (mean age=21.28±2.71years). The prevalence varied by gender, and it was greater among male students. CONCLUSION: Our findings indicated that there was a high prevalence of migraine among the medical students in our study, and these findings were consistent with those of previous studies in Iran and other countries.