Preliminary studies on the effect of excretory secretory (ES) Ascaris lumbricoides antigens on colorectal cell line viability.

Helminth parasites are a group of complex metazoans from various taxonomic families. Excretory secretory (ES) by-products, secreted by living parasites from the surface, appeared to modulate the host immunological response towards helminth infection. This study aims to investigate the effect of ES antigen from helminth parasite on colorectal cell viability. Worm were cultured in phosphate-buffered saline (PBS x1) at 37°C for 24 hours after being rinsed in sterile PBS. Using a mortar and pestle, the worm was crushed vigorously using PBS. The obtained excretory secretory (ES) antigens were extracted and filtered using a 0.22 µM filter and stored at -20°C for further assay. For LCMS, 100 µl of the extract was analysed using Agilent ZORBAX Eclipse Plus C18 Rapid Resolution HT. The extraction of ES antigen (10 µg/ml and 20 µg/ml) was used for cell viability studies using CRC cell line HCT 116. Cell viability and MTT assay were conducted as per the protocol mentioned in the MTT kit. The liquid chromatography and mass spectrometry (LCMS) data indicated that the ES antigen contained metabolic compounds, namely fatty acid, amino alcohol, indoles, sterols, glycosides, and sphingoids. For the Ascaris lumbricoides LCMS analyses, around 405 metabolic peaks were detected. Out of which, 58 were detected via the database were identified, while several compounds detected have anticancer properties. The MTT assay indicated that after 24 hours and 48 hours of exposure, all treated cells showed a decrease in cell viability compared to the control group. The preliminary studies demonstrated that the ES antigen from Ascaris lumbricoides has some ability to decrease the cell viability of the HCT116 CRC cell line. Further studies are needed to examine the cell cycle arrest and apoptosis effect of the ES antigen towards the CRC cell line.

Wolbachia infection is widespread in brackish and fresh water Aedes albopictus (Diptera: Culicidae) in the coastal Jaffna peninsula of northern Sri Lanka.

BACKGROUND & OBJECTIVES: Aedes albopictus and Aedes aegypti are important vectors of dengue and many other arboviral diseases in tropical and sub-tropical locations. Both vectors are tolerant of salinity in the dengue-endemic coastal Jaffna peninsula of northern Sri Lanka. Aedes albopictus pre-imaginal stages are found in field brackish water habitats of up to 14 parts per thousand (ppt, gL-1) salt in the Jaffna peninsula. Salinity-tolerance in Aedes is characterized by significant genetic and physiological changes. Infection with the wMel strain of the endosymbiont bacterium Wolbachia pipientis reduces dengue transmission in the field by Ae. aegypti, and the same approach is also being considered for Ae. albopictus. In this context, we investigated natural Wolbachia infections in brackish and fresh water field isolates of Ae. albopictus in the Jaffna district. METHODS: Aedes albopictus collected as pre-imaginal stages using conventional ovitraps in the Jaffna peninsula and adjacent islands of the Jaffna district were screened by PCR utilizing strain-transcending primers for the presence of Wolbachia. Wolbachia strains were then further identified by PCR using strain-specific primers for the Wolbachia surface protein gene wsp. The Jaffna wsp sequences were compared by phylogenetic analysis with other wsp sequences available in Genbank. RESULTS: Aedes albopictus were found to be widely infected with the wAlbA and wAlbB strains of Wolbachia in Jaffna. The partial wAlbB wsp surface protein gene sequence in Jaffna Ae. albopictus was identical to a corresponding sequence from South India but different from that in mainland Sri Lanka. INTERPRETATION & CONCLUSION: Widespread infection of salinity-tolerant Ae. albopictus with Wolbachia is a factor to be considered when developing Wolbachia-based dengue control in coastal areas like the Jaffna peninsula.

Palmitic acid of Musa Paradisiaca induces apoptosis through caspase-3 in human oral squamous cell carcinoma.

OBJECTIVE: Despite apoptosis processes being conserved, cancer cells have developed mechanisms to inhibit apoptosis by altering anti-apoptotic molecules or inactivating pro-apoptotic. The aim of this study was to determine the palmitic acid of Musa paradisiaca var. sapientum (L) Kunz (MP) stem extracts against human oral squamous cell carcinoma (hOSCC) through caspase-3. MATERIALS AND METHODS: Ethanol and ethyl acetate extracts of MP stem were analyzed by gas chromatography-mass spectrometry (GC-MS). Computerized models of chemically active compounds were used to predict anticancer activity. Cytotoxicity was evaluated in Artemia salina Leach and hOSCC (OM-1) culture at concentrations 100, 90, 80, 70, 60, 50, 40, 30, 20, and 10 µg/mL respectively. The expression level of caspase-3 on hOSCC was measured by enzyme-linked immunoassay (ELISA). RESULTS: We found seven chemically active compounds in the ethanol extract and 15 compounds in the ethyl acetate extract of MP stem. The major component was hexadecanoic acid of palmitic acid derivates, and this was predicted to have anticancer activities as apoptosis through caspase-3 stimulants. However, cytotoxicity effects against hOSCC culture were assessed by values of the 50% inhibitory concentration (IC50) of 15.00 µg/mL for the ethanol extract, and an IC50 of 10.61 µg/mL for the ethyl acetate. There was a significant increase of caspase-3 level on treatment groups compared to control. CONCLUSIONS: Hexadecanoic acid of MP stem extracts has anticancer activity by inhibiting cell growth of hOSCC culture through caspase-3 stimulants.

Reduced dengue incidence during the COVID-19 movement restrictions in Sri Lanka from March 2020 to April 2021.

BACKGROUND: Dengue is the major mosquito-borne disease in Sri Lanka. After its first detection in January 2020, COVID-19 has become the major health issue in Sri Lanka. The impact of public health measures, notably restrictions on movement of people to curb COVID-19 transmission, on the incidence of dengue during the period March 2020 to April 2021 was investigated. METHODS: The incidence of dengue and COVID-19, rainfall and the public movement restrictions implemented to contain COVID-19 transmission were obtained from Sri Lanka government sources. A Seasonal Autoregressive Integrated Moving Average (SARIMA) model was used to predict the monthly dengue incidence from March 2020 to April 2021 for each of the country's 25 districts based on five years of pre-pandemic data, and compared with the actual recorded incidence of dengue during this period. Ovitrap collections of Aedes larvae were performed in Jaffna city in the Jaffna district from August 2020 to April 2021 and the findings compared with similar collections made in the pre-pandemic period from March 2019 to December 2019. RESULTS: The recorded numbers of dengue cases for every month from March 2020 to April 2021 in the whole country and for all 25 districts over the same period were lower than the numbers of dengue cases predicted from data for the five years (2015-2019) immediately preceding the COVID-19 pandemic. The number of dengue cases recorded nationwide represented a 74% reduction from the predicted number of dengue cases for the March 2020 to April 2021 period. The numbers of Aedes larvae collected from ovitraps per month were reduced by 88.6% with a lower proportion of Ae. aegypti than Ae. albopictus in Jaffna city from August 2020 until April 2021 compared with March 2019 to December 2019. CONCLUSION: Public health measures that restricted movement of people, closed schools, universities and offices to contain COVID-19 transmission unexpectedly led to a significant reduction in the reported numbers of dengue cases in Sri Lanka. This contrasts with findings reported from Singapore. The differences between the two tropical islands have significant implications for the epidemiology of dengue. Reduced access to blood meals and lower vector densities, particularly of Ae. aegypti, resulting from the restrictions on movement of people, are suggested to have contributed to the lower dengue incidence in Sri Lanka.

An aerobic oxidation of alcohols into carbonyl synthons using bipyridyl-cinchona based palladium catalyst.

We have reported an aerobic oxidation of primary and secondary alcohols to respective aldehydes and ketones using a bipyridyl-cinchona alkaloid based palladium catalytic system (PdAc-5) using oxygen at moderate pressure. The PdAc-5 catalyst was analysed using SEM, EDAX, and XPS analysis. The above catalytic system is used in experiments for different oxidation systems which include different solvents, additives, and bases which are cheap, robust, non-toxic, and commercially available on the industrial bench. The obtained products are quite appreciable in both yield and selectivity (70-85%). In addition, numerous important studies, such as comparisons with various commercial catalysts, solvent systems, mixture of solvents, and catalyst mole%, were conducted using PdAc-5. The synthetic strategy of oxidation of alcohol into carbonyl compounds was well established and all the products were analysed using 1H NMR, 13CNMR and GC-mass analyses.

The accuracy of Infrared sensor detection in a smart toilet.

Background: Infrared (IR) sensors are useful tools for detecting distance and proximity. However, these sensors are not good at detecting edges of an area, therefore when used in a smart toilet it has difficulty in detecting the orientation and position of the user's body. The aim of this study was to design an IR sensor for a smart toilet with a more accurate and consistent detection. Methods: A total of 12(six men and six women) participants with different body types were involved in this study. IR sensor detection was tested in the sitting and squatting toilets. For the best accuracy, the IR sensor's angle was measured. Red, blue, and red-blue plastic covers were used, as these colors improve precision. The microcontroller was set up to calculate the participant's distance and presence in the cubicle. Results: Toilet positioning varied greatly depending on whether one is sitting or squatting. For sitting toilet, the red cover was close to the accurate distance at a 172° angle. IR detected a man but not a woman's body. The blue cover provided the same best angle of 172° with a higher sensor distance. When the red and blue cover combination was applied, the reading of 141cm detected both men and women, at 172° angle. The actual distance for squatting toilets was 158cm. The optimal angle for both red and blue covers was 176°, however the sensor distance was greater for the blue cover. Finally, the red and blue cover combination gave a more accurate distance of up to 163cm from the actual reading, when detecting both genders at a normal angle of 76°. Conclusion: The combination of red and blue cover gave the most accurate detection for the squatting and sitting toilets. The best angle for sitting was 172°, and for squatting was 176°.

Variation in collagenase Clostridium histolyticum practice patterns: a Survey of ISSM Members.

Collagenase clostridium histolyticum (CCH, Xiaflex, Xiapex) is the only FDA-approved medication for treatment of Peyronie's disease. It is unclear how practitioners actually use CCH in their own practices. The objectives of the study were: (1) to identify variability in practice patterns for CCH among practitioners, (2) to assess adherence to the package insert instructions, and (3) to evaluate whether provider satisfaction was associated with adherence to instructions. A 30-question online survey was distributed to 1270 members of the International Society for Sexual Medicine (ISSM) from the EU, USA, Canada and Australia. Of the 30 questions, 10 survey questions had only one response consistent with the CCH package insert recommendations. An "adherence" score was calculated for each survey participant depending on how many of these questions were answered correctly. The average adherence scores of various groups were compared using a student's t-test. A chi-squared test was used to determine association between categorical variables. Of 202 total responses, 132 practitioners reported using CCH out of 1270 ISSM members from countries where CCH is available (10.4% response rate). Practitioners from outside the USA were more likely to be satisfied with CCH (p = 0.006), and more experienced users (>20 uses) were more likely to be satisfied than less experienced users (<10 uses) (p = 0.046). Satisfied users of CCH did not have significantly different adherence scores than non-satisfied users. Even though 67% of practitioners believed they followed the package insert guidelines, only 11% adhered to all the recommendations evaluated by the survey. Treatment adherence to package insert guidelines does not appear to be associated with provider satisfaction. We believe there is utility in seeing a snapshot of these practice patterns so practitioners may feel more comfortable adapting their own practice in light of newer data supporting alternative administration methods.

Using 17-OHP as Serum Biomarker to Monitor Therapy in Patients With Hypogonadotropic Hypogonadism.

Exogenous testosterone administration decreases intratesticular testosterone (ITT) significantly, an essential hormone for spermatogenesis. Therefore, treatment of patients with hypogonadotropic hypogonadism (HH) who desire infertility can be challenging. These patients are treated with recombinant follicle-stimulating hormone (FSH), clomiphene citrate, and human chorionic gonadotropin (hCG) to increase their ITT. However, there is no approved serum biomarker for ITT and it can only be measured via invasive testicular biopsy or aspiration. Previous authors have speculated that serum 17-hydroxyprogestrone (17-OHP) can be used as serum biomarker for ITT. In our case report, we demonstrate increase in 17-OHP associated with spermatogenesis after commencing treatment for infertility in patient with HH.

Salinity tolerant Aedes aegypti and Ae. albopictus-Infection with dengue virus and contribution to dengue transmission in a coastal peninsula.

BACKGROUND & OBJECTIVES: Aedes aegypti and Ae. albopictus are major arboviral vectors that are considered to lay eggs, and undergo preimaginal development only in fresh water collections. However, recently they have been also shown to develop in coastal brackish water habitats. The ability of the biologically variant salinity-tolerant Aedes vectors to transmit arboviral diseases is unknown. We therefore, investigated the infection of salinity-tolerant Aedes mosquitoes with dengue virus (DENV) and analysed dengue incidence and rainfall data to assess the contribution of salinity-tolerant Aedes vectors to dengue transmission in the coastal Jaffna peninsula in Sri Lanka. METHODS: Brackish and fresh water developing female Ae. aegypti and Ae. albopictus were tested for their ability to become infected with DENV through in vitro blood feeding and then transmit DENV vertically to their progeny. An immunochromatographic test for the NS1 antigen was used to detect DENV. Temporal variation in dengue incidence in relation to rainfall was analysed for the peninsula and other parts of Sri Lanka. RESULTS: Aedes aegypti and Ae. albopictus developing in brackish water, became infected with DENV through in vitro blood feeding and the infected mosquitoes were able to vertically transmit DENV to their progeny. Monsoonal rainfall was the discernible factor responsible for the seasonal increase in dengue incidence in the peninsula and elsewhere in Sri Lanka. INTERPRETATION & CONCLUSION: Fresh water Aedes vectors are main contributors to the increased dengue incidence that typically follows monsoons in the Jaffna peninsula and elsewhere in Sri Lanka. It is possible however, that brackish water-developing Aedes constitute a perennial reservoir for DENV to maintain a basal level of dengue transmission in coastal areas of the peninsula during the dry season, and this supports increased transmission when monsoonal rains expand populations of fresh water Aedes.

Correction to: Development of a sensitive PCR-dot blot assay to supplement serological tests for diagnosing Lyme disease.

In the original version of this article, the word "flagellin" is not correct. The correct word should be "P66" throughout the body of the article.

Development of a sensitive PCR-dot blot assay to supplement serological tests for diagnosing Lyme disease.

Laboratory diagnosis of Lyme disease is difficult and presently dependent on detecting Borrelia burgdorferi-specific antibodies in patient serum with the disadvantage that the immune response to B. burgdorferi can be weak or variable, or alternatively, the slow and inefficient culture confirmation of B. burgdorferi. PCR tests have previously shown poor sensitivity and are not routinely used for diagnosis. We developed a sensitive and specific Lyme Multiplex PCR-dot blot assay (LM-PCR assay) applicable to blood and urine samples to supplement western blot (WB) serological tests for detecting B. burgdorferi infection. The LM-PCR assay utilizes specific DNA hybridization to purify B. burgdorferi DNA followed by PCR amplification of p66 [corrected] and OspA gene fragments and their detection by southern dot blots. Results of the assay on 107 and 402 clinical samples from patients with suspected Lyme disease from Houston, Texas or received at the IGeneX laboratory in Palo Alto, California, respectively, were analyzed together with WB findings. The LM-PCR assay was highly specific for B. burgdorferi. In the Texas samples, 23 (21.5%) patients antibody-negative in WB assays by current US Centers for Disease Control (CDC) recommended criteria were positive by LM-PCR performed on urine, serum or whole blood samples. With IGeneX samples, of the 402 LM-PCR positive blood samples, only 70 met the CDC criteria for positive WBs, while 236 met IGeneX criteria for positive WB. Use of the LM-PCR assay and optimization of current CDC serological criteria can improve the diagnosis of Lyme disease.

A rare ANOS1 variant in siblings with Kallmann syndrome identified by whole exome sequencing.

Kallmann syndrome is a rare genetic condition causing congenital hypogonadotropic hypogonadism. It presents with delayed puberty, anosmia, and infertility. Here, we set out to identify a causative DNA variant for Kallmann syndrome in two affected brothers of Hispanic ancestry. The male siblings presented with a clinical diagnosis of Kallmann syndrome (anosmia, delayed puberty, azoospermia, and undetectable luteinizing hormone and follicle stimulating hormone levels). Genetic variations were investigated by whole exome sequencing. Potentially pathogenic variants were filtered and prioritized followed by validation by Sanger sequencing in the two brothers and their mother. A pathogenic variant was identified in the ANOS1 gene on the X chromosome: c.1267C>T; both brothers were hemizygous, and their mother was heterozygous for the variant. The variant is a single nucleotide change that introduces a stop codon in exon 9 (p.R423*), likely producing a truncated variant of the protein. This variant has only been reported twice in the literature, in the setting of finding genetic causes for other conditions. This result supports the clinical value of whole exome sequencing for identification of genetic pathogenic variants. Genetic diagnosis is the essential first step for genetic counseling, preimplantation diagnosis, and research for a potential treatment.

Morphological and molecular identification of cryptic species in the Sergentomyia bailyi (Sinton, 1931) complex in Sri Lanka.

The correct identification of sand fly vectors of leishmaniasis is important for controlling the disease. Genetic, particularly DNA sequence data, has lately become an important adjunct to the use of morphological criteria for this purpose. A recent DNA sequencing study revealed the presence of two cryptic species in the Sergentomyia bailyi species complex in India. The present study was undertaken to ascertain the presence of cryptic species in the Se. bailyi complex in Sri Lanka using morphological characteristics and DNA sequences from cytochrome c oxidase subunits. Sand flies were collected from leishmaniasis endemic and non-endemic dry zone districts of Sri Lanka. A total of 175 Se. bailyi specimens were initially screened for morphological variations and the identified samples formed two groups, tentatively termed as Se. bailyi species A and B, based on the relative length of the sensilla chaeticum and antennal flagellomere. DNA sequences from the mitochondrial cytochrome c oxidase subunit I (COI) and subunit II (COII) genes of morphologically identified Se. bailyi species A and B were subsequently analyzed. The two species showed differences in the COI and COII gene sequences and were placed in two separate clades by phylogenetic analysis. An allele specific polymerase chain reaction assay based on sequence variation in the COI gene accurately differentiated species A and B. The study therefore describes the first morphological and genetic evidence for the presence of two cryptic species within the Se. bailyi complex in Sri Lanka and a DNA-based laboratory technique for differentiating them.

New York University School of Medicine Drug Development Educational Program: 2-Year Benchmark.

Drug development (DD) is a multidisciplinary process that spans the translational continuum, yet remains an understudied entity in medical schools and biomedical science institutes. In response to a growing interest and unmet need, we implemented a DD course series that details identification of viable molecular targets, clinical trial design, intellectual property, and marketing. Enrollment is open to faculty, postdoctoral trainees, and MD, PhD, and MS students. After 2 years, 37 students and 23 students completed the fall and spring courses, respectively. Pre/post-surveys demonstrated gained knowledge across course topics, with mean survey scores increased by 66% (p < 0.001) after each course. Lectures for each course were consistently rated highly, with a mean course rating of 4.1/5. Through this program, trainees will have a more innovative approach toward identification of therapeutic targets and modalities. Furthermore, they will learn to integrate technology and biomedical informatics to find creative solutions in the DD process.

Generation and characterisation of human umbilical cord derived mesenchymal stem cells by explant method.

Mesenchymal stem cells (MSCs) derived from human umbilical cord (UC) have been considered as an important tool for treating various malignancies, tissue repair and organ regeneration. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) are better alternative to MSCs that derived from bone marrow (BM-MSCs) as they are regarded as medical waste with little ethical concern for research and easily culture-expanded. In this present study, the foetal distal end of human UC was utilised to generate MSC by explant method. Upon in vitro culture, adherent cells with fibroblastic morphology were generated with rapid growth kinetics. Under the respective inductive conditions, these cells were capable of differentiating into adipocytes and osteocytes; express an array of standard MSC's surface markers CD29, CD73, CD90, CD106 and MHC-class I. Further assessment of immunosuppression activity revealed that MSCs generated from UC had profoundly inhibited the proliferation of mitogen-activated T lymphocytes in a dosedependent manner. The current laboratory findings have reinforced the application of explant method to generate UCMSCs thus, exploring an ideal platform to fulfil the increasing demand of MSCs for research and potential clinical use.

Emerging Targets for Therapeutic Development in Diabetes and Its Complications: The RAGE Signaling Pathway.

Types 1 and 2 diabetes are on the rise worldwide. Although the treatment of hyperglycemia has benefited from recent advances, aggressive efforts to maintain euglycemia may be fraught with risk, especially in older subjects or in subjects vulnerable to hypoglycemic unawareness. Hence, strategies to prevent and treat the complications of hyperglycemia are essential. In this review we summarize recent updates on the biology of the receptor for advanced glycation endproducts (RAGE) in the pathogenesis of both micro- and macrovascular complications of diabetes, insights from the study of mouse models of obesity and diabetic complications, and from associative studies in human subjects. The study of the mechanisms and consequences of the interaction of the RAGE cytoplasmic domain with the formin, mDia1, in RAGE signal transduction, will be discussed. Lastly, we review the "state-of-the-art" on RAGE-directed therapeutics. Tackling RAGE/mDia1 may identify a novel class of therapeutics preventing diabetes and its complications.

Microscopic visualization of intravasal spermatozoa is positively associated with patency after bilateral microsurgical vasovasostomy.

We evaluated pre-operative and intraoperative factors associated with successful patency following bilateral microsurgical vasovasostomy (VV). We retrospectively reviewed the charts of 1331 men who underwent bilateral VV by two surgeons between 2006 and 2013. Vasal fluid was examined intraoperatively for gross quality (i.e., clear or opaque and creamy/thick) and for the presence of spermatozoa on microscopy (i.e., whole spermatozoa, sperm fragments, or azoospermia). Post-operative patency was assessed by semen analysis or patient report of conception. Perioperative factors were explored using descriptive statistics and examined in logistic regression models for associations with post-operative patency. The median age at VV was 39 years [interquartile range (IQR): 35-44] and the median obstructive interval (OI) was 7 years (IQR: 4-11). Overall, 1307 patients achieved post-operative patency (98%) while 24 remained obstructed (2%). Among those who became patent, 410 reported conception. After adjustment for potential confounders, only microscopic examination of the intravasal fluid for the presence of spermatozoa (bilateral or unilateral whole spermatozoa vs. sperm parts/azoospermia) at the time of VV was significantly associated with post-operative patency with an odds ratio (OR) of 14.2 (95% CI: 5.8-34.9; p = <1 × 10(-8) ). Identification of bilateral or unilateral sperm fragments vs. azoospermia was also associated with increased odds of post-operative patency with an OR of 3.5 (95% CI: 0.9-13.6; p = 0.08). There was no statistically significant association between age at VV, OI, presence of granuloma, gross fluid quality, or surgeon and post-operative patency after controlling for potential confounders. Identification of whole spermatozoa in the vasal fluid at the time of VV was positively associated with post-operative patency. Our findings stress the need for intraoperative microscopy to aid in post-operative patient counseling.

Effect of orally administered soy milk fermented with Lactobacillus plantarum LAB12 and physical exercise on murine immune responses.

Probiotics are live microorganisms that confer health benefits through the gastrointestinal microbiota. This nutritional supplement may benefit athletes who undergo rigorous training by maintaining their gastrointestinal functions and overall health. In this study the influence of moderate physical exercise using a graded treadmill exercise, alone or in combination with the consumption of a soy product fermented with Lactobacillus plantarum LAB12 (LAB12), on tumour necrosis factor alpha (TNF-α) responses was investigated in a murine model. Male BALB/c mice were randomly divided into four groups of six mice each (control, exercise alone, LAB12 and LAB12 + exercise). Mice treated with the potential probiotic LAB12 were orally gavaged for 42 days. At autopsy, blood and spleen from the animals were collected. The splenocytes were cultured in the presence of a mitogen, concanavalin A (Con A). The amount of TNF-α produced by the Con A-stimulated splenocytes was quantified using ELISA, while their proliferation was determined using the [(3)H]-thymidine incorporation method. This study shows that LAB12-supplemented and exercise-induced mice showed marked increase (P<0.05) in cell proliferation compared to the control animals. TNF-α production was suppressed (P<0.05) in the LAB12 group compared to the untreated mice. These results demonstrate that supplementation with LAB12 has immunomodulatory effects, under conditions of moderate physical exercise, which may have implications for human athletes. Further investigation in human trials is warranted to confirm and extrapolate these findings.

Effects of cigarette smoking on erectile dysfunction.

Cigarette smoking is a leading cause of preventable morbidity and mortality in the United States. Although public policies have resulted in a decreased number of new smokers, smoking rates remain stubbornly high in certain demographics with 20% of all American middle-aged men smoking. In addition to the well-established harmful effects of smoking (i.e. coronary artery disease and lung cancer), the past three decades have led to a compendium of evidence being compiled into the development of a relationship between cigarette smoking and erectile dysfunction. The main physiologic mechanism that appears to be affected includes the nitric oxide signal transduction pathway. This review details the recent literature linking cigarette smoking to erectile dysfunction, epidemiological associations, dose dependency and the effects of smoking cessation on improving erectile quality.