Teeth clenching reduces arm abduction force

It has been reported that the 90° arm abduction force counteracting external adduction loads appeared to be smaller under teeth clenching condition than under non-clenching condition. To elucidate the physiological mechanism underlying the possible inhibitory effect of teeth clenching on the arm abduction, we have attempted to quantify the difference in the force induced against the fast and slow ramp load between the arm abductions under teeth non-clenching and clenching conditions. When the load of adduction moment was linearly increased, the abductor force increased to a maximal isometric contraction force (MICF) and further increased to a maximal eccentric contraction force (MECF) with forced adduction. The MICF measured under teeth clenching was significantly lower than that under non-clenching, despite no significant difference in the MECF between the two conditions. The reduction in MICF caused by teeth clenching was enhanced by increasing the velocity of the load. These results suggest that clenching inhibits abduction force only during isometric contraction phase. The invariability of MECF would indicate the lack of involvement of fatigue in such inhibitory effects of clenching. To discover the source of the inhibition, we have examined the effects of teeth clenching on the stretch reflex in the deltoid muscle. The stretch reflex of deltoid muscles was inhibited during clenching, contrary to what was expected from the Jendrassik maneuver. Taken together, our results suggest that the teeth clenching reduced the MICF by depressing the recruitment of deltoid motoneurones presumably via the presynaptic inhibition of spindle afferent inputs onto those motoneurones.     

Disturbed Left Atrial Function is Associated with Paroxysmal Atrial Fibrillation in Hypertension

Background

Hypertension is the most prevalent and modifiable risk factor for atrial fibrillation. The pressure overload in the left atrium induces pathophysiological changes leading to alterations in contractile function and electrical properties.

Objective

In this study our aim was to assess left atrial function in hypertensive patients to determine the association between left atrial function with paroxysmal atrial fibrillation (PAF).

Method

We studied 57 hypertensive patients (age: 53±4 years; left ventricular ejection fraction: 76±6.7%), including 30 consecutive patients with PAF and 30 age-matched control subjects. Left atrial (LA) volumes were measured using the modified Simpson''s biplane method. Three types of LA volume were determined: maximal LA(LAVmax), preatrial contraction LA(LAVpreA) and minimal LA volume(LAVmin). LA emptying functions were calculated. LA total emptying volume = LAVmax−LAVmin and the LA total EF = (LAVmax-LAVmin )/LAVmax, LA passive emptying volume = LAVmax− LAVpreA and the LA passive EF = (LAVmax-LAVpreA)/LAVmax, LA active emptying volume = LAVpreA−LAVmin and LA active EF = (LAVpreA-LAVmin )/LAVpreA.

Results

The hypertensive period is longer in hypertensive group with PAF. LAVmax significantly increased in hypertensive group with PAF when compared to hypertensive group without PAF (p=0.010). LAAEF was significantly decreased in hypertensive group with PAF as compared to hypertensive group without PAF (p=0.020). A'' was decreased in the hypertensive group with PAF when compared to those without PAF (p = 0.044).

Conclusion

Increased LA volume and impaired LA active emptying function was associated with PAF in untreated hypertensive patients. Longer hypertensive period is associated with PAF.     

Two-suture fish-mouth end-to-side microvascular anastomosis with fibrin glue

The most decisive step during free tissue transfers and replantation surgery may be respected as microvascular anastomosis. The conventional end-to-side anastomosis technique with simple interrupted sutures is well established and proven to be successful. On the other hand, conventional technique can be time consuming and can cause vascular thrombosis, vessel narrowing, and foreign-body reactions. Search for a more rapid and secure alternative to conventional technique is carried on. In this study, we defined a new technique for end-to-side anastomosis with fish-mouth incisions and application of fibrin glue and compared our results with those we obtained with conventional end-to-side anastomosis. We evaluated end-to-side anastomosis of carotid arteries of a total number of 64 Wistar-Albino rats. In control group (n = 32), conventional anastomoses with 8 to 10 sutures were performed. In experimental group (n = 32), fish-mouth incisions were applied first on the recipient artery, followed by performing anastomosis with only 2 corner sutures and applying commercially available fibrin glue. Time taken to perform the anastomosis was significantly shorter with the experimental group (P = 0.001), whereas early and late patency and aneurysm rates were comparable to those achieved with control group. Histological evaluation did not point out any significant differences between the groups. We have defined a rapid and safe alternative technique of end-to-side anastomosis with the use of fibrin glue. This method may be an alternative especially where multiple anastomoses are required or where it is difficult to approach anastomotic line, as it is easily performed, rapid, safe, and not involving any complex equipments.     

Negative serology: could exclude the diagnosis of brucellosis?

Two cases of brucellar spondylodiscitis of the lumbar area were presented. Although both cases showed typical radiological changes, serological tests could not detect Brucella agglutinating antibodies. One of the patients was bacteremic and Brucella spp. was identified from blood culture. In the second patient needle biopsy was required for definite diagnosis. Although small, serologic tests have a certain rate of false negative results in brucellosis. Thus, a negative serology should not exclude the diagnosis of brucellosis, as it is demonstrated in the current cases.     

Distribution of gene mutations associated with familial normosmic idiopathic hypogonadotropic hypogonadism

Objective: Normosmic idiopathic hypogonadotropic hypogonadism (nIHH) is characterized by failure of initiation or maintenance of puberty due to insufficient gonadotropin release, which is not associated with anosmia/hyposmia. The objective of this study was to determine the distribution of causative mutations in a hereditary form of nIHH. Methods: In this prospective collaborative study, 22 families with more than one affected individual (i.e. multiplex families) with nIHH were recruited and screened for genes known or suspected to be strong candidates for nIHH. Results: Mutations were identified in five genes (GNRHR, TACR3, TAC3, KISS1R, and KISS1) in 77% of families with autosomal recessively inherited nIHH. GNRHR and TACR3 mutations were the most common two causative mutations occurring with about equal frequency. Conclusions: Mutations in these five genes account for about three quarters of the causative mutations in nIHH families with more than one affected individual. This frequency is significantly greater than the previously reported rates in all inclusive (familial plus sporadic) cohorts. GNRHR and TACR3 should be the first two genes to be screened for diagnostic purposes. Identification of causative mutations in the remaining families will shed light on the regulation of puberty.     

Evaluation of choroidal thickness and choroidal vascularity index during pregnancy

ObjectiveTo assess the choroidal structural characteristics in the first and third trimesters in pregnant women using enhanced depth imaging optical coherence tomography and binarization method.DesignProspective study.ParticipantsTwenty-five eyes of 25 pregnant women in the first trimester (group 1) and 25 eyes of 25 pregnant women in the third trimester (group 2) were examined. Healthy age-matched 25 participants were enrolled as a control group (group 3).MethodsThe choroidal thickness (CT) was measured at 3 points; subfoveal, 1500 μm nasal to the fovea, and 1500 μm temporal to the fovea. Total choroidal area, luminal area, stromal area, stroma/lumen ratio, and choroidal vascularity index (CVI) were measured by Image-J software.ResultsThe mean subfoveal and nasal CT were statistically significantly increased in group 1 compared with controls (p = 0.005 and p = 0.004, respectively). The mean temporal CT was statistically significantly increased in group 1 compared with groups 2 and 3 (group 1 vs group 2, p = 0.043; group 1 vs group 3, p = 0.011). The mean total choroidal area, stromal area, and luminal area were significantly increased in groups 1 and 2 compared with control group (p < 0.001, p < 0.001, p < 0.001, and p < 0.001, p = 0.002, p = 0.002, respectively). There were no statistically significant differences among groups in terms of mean stroma/lumen ratio and CVI (p = 0.148 and p = 0.312, respectively).ConclusionsThere was a significant increase in subfoveal, temporal, and nasal CT in the first trimester. Total choroidal, stromal, and luminal areas were significantly increased in the first and third trimesters.     

Lateral internal sphincterotomy versus 0.25 % isosorbide dinitrate ointment for chronic anal fissures: a prospective randomized controlled trial

Purpose

To compare the healing properties of lateral internal sphincterotomy (LIS) and isosorbide dinitrate (ISDN) ointment for chronic anal fissure.

Methods

Patients with a chronic anal fissure were randomly assigned to a group treated with ISDN ointment (n = 105) or a group treated with LIS (n = 102). The same investigators examined the patients in a blinded manner, 1, 2, 3, 6, and 12 months after the treatments.

Results

The anal fissure had healed completely by 4 weeks in 64.7 versus 92.2 %, and by 6 months in 77.1 versus 97.1 % of the ISDN and LIS group patients, respectively. At 12 months, the recurrence rates were 4.8 versus 1 % for the ISDN and LIS groups, respectively, and the success rates of the treatments were 72.4 versus 96.1 %, respectively. Six patients in the LIS group experienced minor fecal incontinence, and seven (6.7 %) patients in the ISDN group experienced headaches that responded well to paracetamol.

Conclusion

ISDN ointment was reported by all patients to be easy to use. Although its success rate was lower than that of surgery, ISDN can be offered to selected patients with a chronic anal fissure, as it has a low recurrence rate and rare side effects are rare.