Physiologic Basis Of Digital–Rectal Stimulation For Bowel Evacuation In Patients With Spinal Cord Injury: Identification Of An Anorectal Excitatory Reflex

Abstract

Background and purpose: Although advances in rehabilitation practices, pharmacology, and surgery offer new bowel program alternatives, digital-rectal stimulation is still utilized to facilitate defecation in patients with spinal cord injury (SCI) . We speculated that defecation induced by such a technique is mediated through a reflex mechanism.

Methods: The study comprised 18 healthy volunteers (10 men, 8 women, mean age 36.6 ± 9.7 years) and 9 patients with SCI (6 men, 3 women, mean age 35 .1 ± 11 .2 years). The anal canal was dilated by a balloon inflated in 2-ml increments to 10 ml, and rectal pressure response was then recorded. The test was repeated after separate block of the external and internal anal sphincters and after individual anesthetization of the anal canal and rectum.

Results: In normal subjects, the rectal pressure rose significantly (p<0.01) with 2-ml inflation. Increases in anal dilatation effected further rectal pressure elevations (p < 0.001 ), although there were no significant differences among the 4-, 6-, and 10-ml distensions (p > 0.05). The rectal pressure rise occurred with external, but not with internal, sphincter paralysis. In the subjects with paraplegia, there was no rectal pressure response to the 2- and 4-ml anal dilatations, while the 6-, 8-, and 10-ml distensions effected significant pressure increases (p<0.001, p<0.001, p<0.001, respectively) that did not differ significantly among the 3 distending volumes. Internal sphincter inhibition,in contrast to the external sphincter, produced no rectal pressure response. In both normal subjects and subjects with paraplegia, the rectal pressure response did not occur after individual anesthetization of the rectum and anal canal.

Conclusions: Anal dilatation induces rectal contraction through stimulation of mechanoreceptors, possibly in the internal sphincter.Rectal contraction upon anal dilatation suggests a reflex relationship that was absent onindividual anesthetization of the possible2arms of the reflex arc: anal canal and rectum.This relationship, which we term the "anorectal excitatory reflex ," appears to be evoked on digital anal dilatation. The reflexmight be of diagnostic significance in defecationdisorders and has the potential to be used as an investigative tool.     

Effect of Micturition on the External Anal Sphincter: Identification of the Urethro-Anal Reflex

Abstract

Background/Objective: A study on the response of the external anal sphincter (EAS) to the passage of urine through the urethra during micturition could not be found in the literature. We investigated the hypothesis that urine passage through the urethra effects EAS contraction to guard against possible flatus or stool leakage during micturition.

Methods: The study was performed in 23 healthy volunteers (age, 38.6 ± 10.8 [SD] years; 14 men and 9 women). The EAS electromyogram (EMG) was performed during micturition by surface electrodes applied to the EAS. Also, the EAS EMG response to urethral stimulation by a catheter-mounted electrode was registered. The test was repeated after individual anesthetization of the EAS and urethra.

Results: The EAS EMG recorded a significant increase (P < 0.01) during micturition and on urethral stimulation at the bladder neck. Stimulation of the prostatic, membranous, or penile urethra produced no significant change in the EAS EMG. Urethral stimulation after individual EAS and urethral anesthetization did not cause any changes in the EAS EMG.

Conclusions: Urine passing through the urethra or urethral stimulation at the vesical neck produced an increase in the EAS EMG, which presumably denotes EAS contraction, which seems to guard against flatus or fecal leakage during micturition. EAS contraction on urethral stimulation is suggested to be mediated through a urethra-anal reflex. Further studies on this issue may potentially prove the diagnostic significance of this reflex in micturition and defecation disorders.     

Is human papilloma virus associated with salivary gland neoplasms? An in situ-hybridization study

ObjectiveHPV can infect cells of epithelial origin and is closely associated with carcinomas. Studies investigating its presence in salivary gland neoplasms are few and conflicting.MethodsDetection of HPV types 16 &; 18 was done on 34 formalin-fixed, paraffin-embedded archival material of different salivary gland neoplasms using Digene HPV types 16 &; 18 probe using in situ hybridization technique.ResultsEight of neoplastic salivary gland specimens were positively infected by HPV types 16 &; 18. Seven of them were benign (4 Warthin's tumour, 2 pleomorphic adenoma and one myoepithelioma), in addition to one malignant specimen (lymphoma). Correlation was found between the incidence of HPV infection and histological differentiation of salivary gland neoplasms.ConclusionsAn association exists between HPV infections and salivary gland neoplasms. However, given the sparse pattern of reactive cells, it cannot be confirmed that this virus is implicated in the aetiology of this group of tumours.     

A Polymorphism in the Microsomal Triglyceride Transfer Protein Can Predict the Response to Antiviral Therapy in Egyptian Patients with Chronic Hepatitis C Virus Genotype 4 Infection

Background/Aims

A polymorphism in the microsomal triglyceride transfer protein (MTP) is associated with hepatic fibrosis, and carriers showed higher levels of steatosis, higher levels of hepatitis C virus (HCV) RNA and advanced fibrosis. The aim of this study was to study MTP expression pattern in HCV patients and impact of the MTP polymorphism on the response to antiviral therapy.

Methods

One hundred consecutive naive HCV genotype 4 patients were recruited to receive antiviral therapy, and 40 control subjects were also recruited. Demographic, laboratory, and histopathology data were collected. DNA was isolated, and the samples were subjected to polymerase chain reaction analysis and genotyping for MTP by restriction fragment length polymorphism analysis.

Results

Patients and controls were age- and sex-matched (male/female, 56/44, age, 39.2±7.8 years for patients with HCV; male/female, 18/22, age, 38.1±8.1 years for controls). MTP single nucleotide polymorphisms (SNPs) (GG, GT, TT) and alleles (G, T) in the patients versus the controls were 70%, 21%, 9% & 80.5%, 19.5% versus 10%, 87.5%, 2.5% & 53.8%, 46.3%, respectively (p=0.0001). The sustained viral response (SVR) of the patients was 60%. SNPs in MTP genotypes (GG, GT, and TT) and alleles (G and T) in the responders and nonresponders were 71.7%, 25%, 3.3% & 84.2%, 15.8% versus 67.5%, 15%, 17.5% & 75%, 25% (p=0.038 and p=0.109, respectively). A multivariate analysis showed that the GT genotype was an independent predictor of SVR (area under the curve 90% and p=0.0001).

Conclusions

MTP could be a new predictor for SVR to antiviral therapy in patients with HCV genotype 4 infection.     

Impact of single nucleotide polymorphism in tumor necrosis factor-α gene 308G/A in Egyptian asthmatic children and wheezing infants

Bronchial asthma is a common disease with multiple determinants that include genetic variation. Although tumor necrosis factor alpha (TNF-α) is a major pro-inflammatory cytokine, the functions of genetic polymorphisms in this cytokine has not been thoroughly examined in the context of asthma pathology. Therefore, we aimed to investigate whether single nucleotide polymorphism (SNP) in TNF-α is associated with asthma and wheezing and whether the association is related to the severity of the disease and other epidemiological factors. Frequencies of TNF-α-308G/A polymorphism were compared in 100 asthmatic children, 100 wheezy infants and 100 age and gender matched controls. Genotype frequencies for TNF-α-308G/A were significantly higher in asthmatic children (60%) and wheezy infants (68%) than the control group (30%). Higher serum levels of TNF-α were observed in genotypes G/A and G/G of asthmatic children and wheezy infants than in controls. No association was found between the G/A polymorphism and the severity of the disease, the total eosinophil count and IgE levels in both groups. We can conclude that genetic variation in TNF-α-308G/A may contribute to childhood asthma and wheezing. These findings could be helpful for future early intervention studies which may have a potential impact on family counseling and management.     

The multiple faces of nicotine and its implications in tissue and wound repair

Abstract:  Nicotine, one of the thousands of chemicals in cigarette smoke has a highly debated effect on cell proliferation and tissue healing. Recent studies documented its pro-angiogenesis effects by stimulating endothelial cell α7-non-neronal nicotinic acetyl choline receptors (α7 N-nACHR). It is well known that individuals who smoke or have diabetes experience impaired wound healing although for different reasons. This review evaluates several current studies relating to nicotine's ability to mediate cellular activation, migration and angiogenesis in attempts to correlate these data with nicotine's ability to repair wounds in ischaemic tissue. While its beneficial effects are still under investigation, important findings regarding nicotine's acceleration of atherosclerosis, tumor angiogenesis, cell proliferation e and resistance to apoptosis put its systemic use into question. Based on the good and bad sides of nicotine, it is recommended to restrict its utility to local applications.     

Physioanatomical relationship of the external anal sphincter to the bulbocavernosus muscle in the female

Both external anal sphincter (EAS) and bulbocavernosus muscle (BCM) have been shown anatomically and physiologically to constitute one muscle in males. We investigated the hypothesis that the EAS and BCM have similar anatomical pattern in females. The study consisted of cadaveric dissection, electromyographic recordings and inferior rectal nerve stimulation. Bulbocavernosus reflex action was performed in 16 healthy women before and after anesthetization of the EAS and BCM. The EAS extended forward across the perineal body and became continuous with the BCM in the labia majora. Glans clitoris (GC) or inferior rectal nerve stimulation effected synchronous EAS and BCM contractions with identical action potentials. GC stimulation while the EAS or BCM was anesthetized produced neither EAS nor BCM response. Similarly, stimulation of the anesthetized GC produced no EAS or BCM response. The BCM and EAS apparently constitute a single muscle, which seems to play dual and yet synchronous roles in fecal control and sexual response.     

Effect of remifentanil on the hemodynamic responses and recovery profile of patients undergoing single jaw orthognathic surgery

The aim of this study was to compare fentanyl-based versus remifentanil-based anesthesia with regards to the intraoperative hemodynamic stress response and recovery profiles in patients undergoing Le Fort I osteotomy. Seventeen patients were randomly divided into two groups: patients in the F-group received 2 μg/kg fentanyl intravenously followed by an infusion of 0.03–0.06 μg/kg/min, while patients in the R-group received a 0.5 μg/kg bolus of remifentanil followed by an infusion of 0.0625–0.250 μg/kg/min. Mean arterial pressure and heart rate were recorded at the following points: before anesthetic induction, at endotracheal intubation, 5 min after intubation, at incision, just before the osteotomy, during the osteotomy, during the maxillary fracturing, at suturing, at extubation, 5 min after extubation, and then 15 and 30 min postoperatively. Heart rate and mean arterial pressure were significantly lower in the R-group in comparison to the F-group from t₁ to t₉ (P < 0.05). All measured recovery times were significantly shorter in the R-group (P < 0.05). The incidence of postoperative side effects was comparable between groups. Remifentanil-based anesthesia is an appropriate alternative to fentanyl during Le Fort I orthognathic surgery; it promotes hemodynamic stability, blunts the stress response to noxious stimuli, and provides a better recovery profile.     

The outcomes for nasal contact point surgeries in patients with unsatisfactory response to chronic daily headache medications

The nasal contact point may act as a trigger point or peripheral enhancer in patients with chronic daily headaches. A total of 42 patients had unsatisfactory response to medical treatment for chronic daily headache with radiologic evidence of nasal contact point. Of them, 12 (28.5%) patients were positive for the local anesthetic test. Those patients were operated upon to separate this contact by either septoplasties or submucous resections with or without partial turbinectomies. The mean headache frequency was reduced from 22 to 7 days/month. The mean headache severity was reduced from 5.6 to 2.4. Eight (19%) patients became completely free from headache and its medications, six (75%) of them were positive for local anesthetic test. The patients were satisfied with postoperative monotherapy, or headache severity and frequency could be tolerated without medications in 26 (62%) patients. There was no improvement in seven (16.6%) patients and only one patient (2%) became worse. The overall satisfaction was 83 and 81% for positive and negative anesthetic tests, respectively. The average monthly medication cost was reduced from $85 to 32. Nasal contact point surgery for chronic daily headache patients can satisfy them compared to previously unsatisfactory medications. Nasal contact point may contribute to potentiating or triggering chronic daily headache.