Interlimb differences in parameters of aerobic function and local profiles of deoxygenation during double-leg and counterweighted single-leg cycling.

It is typically assumed that in the context of double-leg cycling, dominant (DOMLEG) and nondominant legs (NDOMLEG) have similar aerobic capacity and both contribute equally to the whole body physiological responses. However, there is a paucity of studies that have systematically investigated maximal and submaximal aerobic performance and characterized the profiles of local muscle deoxygenation in relation to leg dominance. Using counterweighted single-leg cycling, this study explored whether peak O2 consumption (V̇o2peak), maximal lactate steady-state (MLSSp), and profiles of local deoxygenation [HHb] would be different in the DOMLEG compared with the NDOMLEG. Twelve participants performed a series of double-leg and counterweighted single-leg DOMLEG and NDOMLEG ramp-exercise tests and 30-min constant-load trials. V̇o2peak was greater in the DOMLEG than in the NDOMLEG (2.87 ± 0.42 vs. 2.70 ± 0.39 L/min, P < 0.05). The difference in V̇o2peak persisted even after accounting for lean mass (P < 0.05). Similarly, MLSSp was greater in the DOMLEG than in the NDOMLEG (118 ± 31 vs. 109 ± 31 W; P < 0.05). Furthermore, the amplitude of the [HHb] signal during ramp exercise was larger in the DOMLEG than in the NDOMLEG during both double-leg (26.0 ± 8.4 vs. 20.2 ± 8.8 µM, P < 0.05) and counterweighted single-leg cycling (18.5 ± 7.9 vs. 14.9 ± 7.5 µM, P < 0.05). Additionally, the amplitudes of the [HHb] signal were highly to moderately correlated with the mode-specific V̇o2peak values (ranging from 0.91 to 0.54). These findings showed in a group of young men that maximal and submaximal aerobic capacities were greater in the DOMLEG than in the NDOMLEG and that superior peripheral adaptations of the DOMLEG may underpin these differences.NEW & NOTEWORTHY It is typically assumed that the dominant and nondominant legs contribute equally to the whole physiological responses. In this study, we found that the dominant leg achieved greater peak O2 uptake values, sustained greater power output while preserving whole body metabolic stability, and showed larger amplitudes of deoxygenation responses. These findings highlight heterogeneous aerobic capacities of the lower limbs, which have important implications when whole body physiological responses are examined.

Near-infrared spectroscopy detects transient decrements and recovery of microvascular responsiveness following prolonged forearm ischemia.

BACKGROUND: Impairments at the microvascular level might lead to more overt cardiovascular complications, therefore, being able to early detect microvascular dysfunction would be beneficial. Thus, the present study investigated whether near-infrared spectroscopy (NIRS) assessment of microvascular responsiveness (reoxygenation slope, %.s-1) would detect the detrimental effects on the forearm microvasculature following a period of arterial occlusion. Similarly, the effects of prolonged forearm ischemia on brachial artery function were also assessed by flow-mediated dilation (%FMD). METHODS: Fourteen individuals were tested before (Pre), immediately after (PostPI), 30 min after (Post30), and 60 min after (Post60) prolonged forearm ischemia. The Pre, Post30, and Post60 interventions consisted of 5 min of blood flow occlusion, whereas the postPI involved a 20-min occlusion period. RESULTS: The reoxygenation slope was reduced at PostPI (1.33 ±â€¯0.72%.s-1 vs. 1.79 ±â€¯0.68%.s-1 Pre; p < 0.05), but not at Post30 (1.93 ±â€¯0.70%.s-1) and Post60 (1.87 ±â€¯0.85%.s-1) (both p > 0.05 vs. Pre). Similarly, the brachial FMD response was reduced at PostPI (7.4 ±â€¯3.9% vs. 10.9 ±â€¯2.9% Pre; p < 0.05), but not at Post30 (11.3 ±â€¯4.1%) or Post60 (11.8 ±â€¯4.3%) (both p > 0.05 vs. Pre). CONCLUSION: These findings show that NIRS-derived reoxygenation slope detects the transient detrimental effects of prolonged ischemia within the forearm microvasculature. Additionally, this study found that the reduction in forearm microvascular responsiveness might have contributed to the decreased brachial artery FMD responsiveness.

Anaphylaxis to lidocaine with tolerance to articaine in a 12 year old girl.

True allergic reactions to local anesthetics are extremely rare and constitute less than 1% of all reactions. In addition, many of those allergic reactions are caused by the preservative constituents of the local anesthetics. Here we report a 12 year old girl with anaphylaxis to lidocaine (an amide local anesthetic) on two occasions. The allergy was confirmed by positive skin prick test to the drug. Skin testing and challenge to another amide local anesthetic (articaine) were negative. Subsequently, its use was well tolerated in a dental procedure. Up to our knowledge, this is the first report of a patient who is allergic to lidocaine and tolerant to articaine.

Periodontitis and Inflammatory Bowel Disease: A Review.

The complex relationship between periodontitis (PD) and inflammatory bowel disease (IBD) has received significant attention in recent studies. Emerging evidence suggests that the oral-gut axis plays a pivotal role in their interaction. This review provides a comprehensive, up-to-date analysis of original research from 2003 to 2023 on the PD-IBD relationship and aims to be a reference for future research. Relevant literature was sourced from the PubMed database using the keywords "periodontitis" and "inflammatory bowel disease". Additionally, a manual library search and a review of bibliographies were conducted. Of the 297 articles retrieved, 27 studies were chosen for final review. Out of these, 21 studies (78%), including both in vitro and in vivo research, indicated an association between PD and IBD. While many studies confirm a bi-directional relationship, others refute it or deem it clinically irrelevant. There is a need for more accessible studies, such as randomized trials, which also investigate the factors that could influence the outcomes to clarify the exact molecular mechanisms and clinical implications of this complex relationship.

Comprehensive Strategies in Endodontic Pain Management: An Integrative Narrative Review.

This narrative review comprehensively examines the current and emerging strategies for pain management in endodontics, encompassing a wide range of pharmacological and non-pharmacological approaches. Through an extensive exploration of 20 distinct parts, the review discusses traditional analgesics, antibiotics, the use of corticosteroids, and the role of novel treatments such as platelet-rich fibrin (PRF) and cryotherapy. The review also delves into the intricacies of clinical methods, such as trephination and occlusal reduction, and discusses the potential of advanced techniques such as GABAergic signaling, acupuncture, in silico modulation, and low-level laser therapy (LLLT) for the effective management of endodontic pain. The analysis reveals a trend toward integrative methods that combine established practices with cutting-edge research, highlighting the importance of a tailored approach in endodontic pain management. The findings underscore the significance of understanding the complex nature of dental pain and the need for multifaceted treatment strategies. The review emphasizes that while traditional pharmacological methods remain foundational, emerging therapies offer promising adjuncts or alternatives, especially in cases where conventional treatments may be inadequate or unsuitable. This review aims to serve as a comprehensive resource for endodontic practitioners and researchers, offering insights into the multifarious aspects of pain management in endodontics. It underscores the ongoing evolution in the field and suggests directions for future research, particularly in refining and validating new pain management techniques.

The near-infrared spectroscopy-derived deoxygenated haemoglobin breaking-point is a repeatable measure that demarcates exercise intensity domains.

OBJECTIVES: A breaking-point in the near-infrared spectroscopy (NIRS)-derived deoxygenated haemoglobin ([HHb]) profile towards the end of a ramp incremental (RI) cycling test has been associated to the respiratory compensation point (RCP). Despite the physiological value of this measure, its repeatability remains unknown. The aim was to examine the repeatability of the [HHb] breaking-point ([HHb]BP) and its association to RCP during a RI cycling test. DESIGN: A repeated measures design was performed on 11 males (30.5±8.4 year; 76.5±8.4kg) and 4 females (30.5±5.9 year; 61.9±4.4 Kg). METHODS: Gas exchange and NIRS [HHb] data were collected during RI tests performed on two different days separated by 48h. The [HHb]BP and the RCP were determined and compared for each trial. RESULTS: The [HHb]BP and the respiratory compensation point (RCP) occurred at the same VO2 in test 1 and test 2 ([HHb]BP: 3.49±0.52Lmin-1 test 1; 3.48±0.45Lmin-1 test 2; RCP: 3.38±0.40Lmin-1 test 1; 3.38±0.44Lmin-1 test 2) (P>0.05). The VO2 associated with the [HHb]BP and the VO2 at RCP were not significantly different from each other either in test 1 as well as in test 2 (P>0.05). Neither test 1 nor test 2 showed significant mean average error between the VO2 at the [HHb]BP and RCP using Bland & Altman plots. CONCLUSIONS: The [HHb]BP is a repeatable measure that consistently occurs towards the end of a RI test. The association between the [HHb]BP and the RCP reinforces the idea that these parameters may share similar mechanistic basis.

Quadriceps Muscles O2 Extraction and EMG Breakpoints during a Ramp Incremental Test.

Muscle deoxygenated breakpoint ([HHb]BP) has been found to be associated with other indices of exercise tolerance in the vastus lateralis (VL) muscle but not in the vastus medialis (VM) and rectus femoris (RF). Purpose: To investigate whether the [HHb]BP occurs also in the VM and RF muscles and whether or not it is associated with other physiological indices of exercise tolerance, such as the EMG threshold (EMGt) and the respiratory compensation point (RCP). Methods: Twelve young endurance trained participants performed maximal ramp incremental (RI) cycling tests (25-30 W·min-1 increments). Muscle oxygen extraction and activity as well as ventilatory and gas exchange parameters were measured. After accounting for the mean response time, the oxygen uptake ([Formula: see text]O2) corresponding to the RCP, [HHb]BP, and the EMGt was determined. Results: Peak power output (POpeak) was 359 ± 48 W. Maximal oxygen consumption ([Formula: see text]O2max) was 3.87 ± 0.46 L·min-1. The [Formula: see text]O2 at the RCP was 3.39 ± 0.41 L·min-1. The [Formula: see text]O2 (L·min-1) corresponding to the [HHb]BP and EMGt were: 3.49 ± 0.46 and 3.40 ± 0.44; 3.44 ± 0.61 and 3.43 ± 0.49; 3.59 ± 0.52, and 3.48 ± 0.46 for VL, VM, and RF, respectively. Pearson's correlation between these thresholds ranged from 0.90 to 0.97 (P < 0.05). No difference was found for the absolute [Formula: see text]O2 and the normalized PO (%) at which the thresholds occurred in all three muscles investigated (P > 0.05). Although in eight out of 12 participants, the [HHb]BP in the RF led to a steeper increase instead of leading to a plateau-like response as observed in the VL and VM, the [Formula: see text]O2 at the breakpoints still coincided with that at the RCP. Conclusions: This study demonstrated that local indices of exercise tolerance derived from different portions of the quadriceps are not different to the systemic index of the RCP.

Hepatitis C virus seroprevalence rate among Saudis.

OBJECTIVE: The aim of the study is to determine the seroprevalence of hepatitis C virus (HCV) in blood donors, children, pregnant women, hemodialysis patients and drug addicts in Saudi Arabia. METHODS: Using third generation enzyme immunoassay kits, we have screened Saudi cohorts of all ages and sexes, namely infants, pre-school, school children, young adults and adults (blood donors and antenatals) for antibodies to HCV. We have also reviewed HCV seroprevalence data among high risk groups from 1998 to 2002. RESULTS: An overall 1.1% (6313 out of 557813) seroprevalence rate was determined among Saudi blood donors; 0.1% (5 out of 3854) in Saudi children; and 0.7% (22 out of 3127) among pregnant women. Hemodialysis patients remain at highest risk of infection at 55.7% whereas intravenous drug addicts have 14% exposure rate. CONCLUSION: We conclude that the present public health schemes have been effective in reducing hepatitis C infection in the general community in the Kingdom of Saudi Arabia but the infection among high risk groups remain a major problem that needs to be actively addressed.

Prevailing genotypes of hepatitis C virus in Saudi Arabia: a systematic analysis of evidence.

BACKGROUND AND OBJECTIVES: Although hepatitis C virus (HCV) genotype 4 has been reported to be prevalent in some countries of the Middle East, the genotype distribution in some geographical areas is not conclusive. We aimed to perform a meta-analysis on available literature on this issue in an attempt to identify or confirm the prevailing HCV genotypes in Saudi Arabia. METHODS: We searched for reports describing genotypes in Saudi Arabia. A meta-analysis was performed on the samples in 18 studies, published between 1995 and 2011, in which HCV genotypes were identified. RESULTS: A total of 2277 specimens from 18 studies showed that 617, 82, 119 and 1198 subjects were HCV-positive for genotypes 1, 2, 3 and 4, respectively. The meta-analyses showed that there is a great deal of heterogeneity in estimated prevalence among the studies. The highest prevalence was found in genotype HCV-4, followed by HCV-1, HCV-3, and HCV-2. CONCLUSION: Our meta-analysei emphasizes that HCV genotype 4 is the most prevalent, followed by genotype 1. Further studies on genotype determination and subtype distribution are warranted.