Contribution of protein conformational heterogeneity to NMR lineshapes at cryogenic temperatures.

While low-temperature Nuclear Magnetic Resonance (NMR) holds great promise for the analysis of unstable samples and for sensitizing NMR detection, spectral broadening in frozen protein samples is a common experimental challenge. One hypothesis explaining the additional linewidth is that a variety of conformations are in rapid equilibrium at room temperature and become frozen, creating an inhomogeneous distribution at cryogenic temperatures. Here, we investigate conformational heterogeneity by measuring the backbone torsion angle (Ψ) in Escherichia coli Dihydrofolate Reductase (DHFR) at 105 K. Motivated by the particularly broad N chemical shift distribution in this and other examples, we modified an established NCCN Ψ experiment to correlate the chemical shift of Ni+1 to Ψi. With selective 15N and 13C enrichment of Ile, only the unique I60-I61 pair was expected to be detected in 13C'-15N correlation spectrum. For this unique amide, we detected three different conformation basins based on dispersed chemical shifts. Backbone torsion angles Ψ were determined for each basin: 114 ± 7° for the major peak and 150 ± 8° and 164 ± 16° for the minor peaks as contrasted with 118° for the X-ray crystal structure (and 118° to 130° for various previously reported structures). These studies support the hypothesis that inhomogeneous distributions of protein backbone torsion angles contribute to the lineshape broadening in low-temperature NMR spectra.

Twist response of actin filaments.

Actin cytoskeleton force generation, sensing, and adaptation are dictated by the bending and twisting mechanics of filaments. Here, we use magnetic tweezers and microfluidics to twist and pull individual actin filaments and evaluate their response to applied loads. Twisted filaments bend and dissipate torsional strain by adopting a supercoiled plectoneme. Pulling prevents plectoneme formation, which causes twisted filaments to sever. Analysis over a range of twisting and pulling forces and direct visualization of filament and single subunit twisting fluctuations yield an actin filament torsional persistence length of ~10 µm, similar to the bending persistence length. Filament severing by cofilin is driven by local twist strain at boundaries between bare and decorated segments and is accelerated by low pN pulling forces. This work explains how contractile forces generated by myosin motors accelerate filament severing by cofilin and establishes a role for filament twisting in the regulation of actin filament stability and assembly dynamics.

Direct Determination of Torsion in Twisted Graphite and MoS2 Interfaces.

The design space of two-dimensional materials is undergoing significant expansion through the stacking of layers in non-equilibrium configurations. However, the lack of quantitative insights into twist dynamics impedes the development of such heterostructures. Herein, we utilize the lateral force sensitivity of an atomic force microscope cantilever and specially designed rotational bearing structures to measure the torque in graphite and MoS2 interfaces. While the extracted torsional energies are virtually zero across all angular misfit configurations, commensurate interfaces of graphite and MoS2 are characterized by values of 0.1533 and 0.6384 N-m/m2, respectively. Furthermore, we measured the adhesion energies of graphite and MoS2 to elucidate the interplay between twist and slide. The adhesion energy dominates over the torsional energy for the graphitic interface, suggesting a tendency to twist prior to superlubric sliding. Conversely, MoS2 displays an increased torsional energy exceeding its adhesion energy. Consequently, our findings demonstrate a fundamental disparity between the sliding-to-twisting dynamics at MoS2 and graphite interfaces.

Insights on Protective Effect of Platelet Rich Plasma and Tadalafil on Testicular Ischemia/Reperfusion Injury in Rats Exposed to Testicular Torsion/Detorsion.

BACKGROUND/AIMS: Ischemic reperfusion (I-R) injury is greatly influenced by the testicular torsion/detorsion process (TDP). In this instance, the anti-inflammatory properties of plateletrich plasma (PRP) combined with tadalafil (Td) significantly promote tissue healing in the I-R injury model. METHODS: Five groups of rats were created: the control group, the I-R group not receiving any therapy, the I-R group receiving a single dosage of Td (0.25 mg/kg, I.P.), the I-R group receiving a single dose of PRP (80 l, intratesticular), and the I-R group receiving both Td and PRP. Sperm morphology, motility, and histology were assessed. The levels of TNF-, BAX, antioxidant status, and testosterone were measured. Additionally, E-selectin expression was done. RESULTS: PRP reduced oxidative stress, inflammation, and apoptosis while also boosting testosterone levels, which alleviated I-R injury. Otherwise, PRP reduces E-selectin expression, which modifies the pathways that control endothelial function. Td also partially demonstrated its testicular-protective activity at the same time. CONCLUSION: PRP's proven anti-inflammatory, antioxidant, and antiapoptotic potentials make it a natural treatment for testicular harm caused by tadalafil. For the first time, it was demonstrated that PRP therapy restored the functionality of the vascular endothelium, specifically the control of E-selectin expression. Combining Td and PRP therapy may be a promising strategy for improving response to PDE5 inhibitors.

Torsion affects the calculation of DNA twisting number.

The topological properties of DNA have long been a focal point in biophysics. In the 1970s, White proposed that the topology of closed DNA double helix follows White's formula: Lk=Wr+Tw. However, there has been controversy in the calculation of DNA twisting number, partly due to discrepancies in the definition of torsion in differential geometry. In this paper, we delved into a detailed study of torsion, revealing that the calculation of DNA twisting number should use the curve's geodesic torsion. Furthermore, we found that the discrepancy in DNA twisting numbers calculated using different torsion is N. This study elucidated the impact of torsion on the calculation of DNA twisting numbers, aiming to resolve controversies in the calculation of DNA topology and provided accurate computational methods and theoretical foundations for related research.

Dermoid cyst management and outcomes: a review of over 1000 cases at a single institution.

BACKGROUND: Mature cystic teratomas represent nearly 60% of benign ovarian neoplasms across all age groups. OBJECTIVE: This study aimed to update existing descriptive studies of ovarian teratomas, including the epidemiology, rate of torsion or malignancy, and treatment modalities in a large modern cohort of patients. STUDY DESIGN: This was a retrospective cross-sectional study of all pathology-confirmed cases of ovarian teratoma that underwent surgery at 1 tertiary care institution from 2004 to 2015. Patient demographics, ovarian cyst characteristics, surgical approach and timing, rate of spillage, and surgical complications were examined. RESULTS: A total of 1054 cases of ovarian teratoma were identified during the study period. There were 113 cases (10.7%) of bilateral teratoma. The mean age at diagnosis was 38 years. The average cyst size was 6.26 cm. The overall rate of torsion was 5.6%, with a higher rate of torsion with increasing cyst size. More than 70% of cases were treated with minimally invasive surgery, which was associated with decreased perioperative complications but an increased risk of cyst spillage. Among 394 patients with cyst spillage, only 1 patient developed chemical peritonitis. The malignant transformation rate of mature cystic teratoma in this cohort was 1.1%. This cohort included 100 pregnant women with mature teratoma. Pregnant patients were more likely to have minimally invasive surgery in the first trimester of pregnancy and more likely to undergo laparotomy in the second or third trimester of pregnancy. CONCLUSION: Similar rates of bilaterality, torsion, malignant transformation, and struma ovarii in ovarian teratomas were found in this large modern cohort compared with previous literature. Most cases of ovarian teratoma can be managed laparoscopically, which is associated with a lower surgical complication rate. Despite the increased risk of cyst spillage with a minimally invasive approach, chemical peritonitis is a rare complication.

The impact of health care on outcomes of suspected testicular torsion: results from the GRAND study.

BACKGROUND: Suspicion of testicular torsion represents a urological emergency, necessitating immediate surgery. Comprehensive data on the current trends and perioperative outcomes regarding surgical exploration are sparse. Therefore, we utilized nationwide data on the prevalence and results of this surgery, aiming to provide evidence on this matter. METHODS: We assessed the GeRmAn Nationwide inpatient Data (GRAND) from 2005 to 2021, provided by the Research Data Center of the Federal Bureau of Statistics. We performed multiple regression analyses to evaluate the perioperative outcomes (length of hospital stay, transfusion, and surgical wound infection) after surgical exploration due to suspected testicular torsion based on both the outcome of surgery (orchiectomy, detorsion with preservation of the testicle, and no testicular torsion) and on the department of operation (urological versus non-urological). RESULTS: A total of 81,899 males underwent surgical exploration due to suspected testicular torsion in Germany from 2005 to 2021. Of them, 11,725 (14%) underwent orchiectomy, 30,765 (38%) detorsion with preservation of the testicle and subsequent orchidopexy, and 39,409 (48%) presented no testicular torsion. Orchiectomy was significantly associated with longer length of hospital stay (day difference of 1.4 days, 95%CI: 1.3-1.4, p < 0.001), higher odds of transfusion (1.8, 95% CI: 1.2-2.6, p = 0.002) and surgical wound infections (1.8, 95%CI: 1.4-2.3, p < 0.001) compared to no testicular torsion. The proportion of patients undergoing orchiectomy was significantly lower in urological departments (14%) versus non-urological departments (16%) and the proportion of patients undergoing preservation of testicle after detorsion was significantly higher in urological departments (38%) versus non-urological departments (37%), p < 0.001. Patients undergoing treatment in a urological department were discharged earlier and presented lower odds of transfusion and surgical wound infection (p < 0.001) compared to patients undergoing treatment in a non-urological department. CONCLUSIONS: Nearly half of patients who underwent surgery for suspected testicular torsion did not have intraoperatively the condition confirmed. Patients treated in urological departments had significantly better perioperative outcomes compared to those treated in non-urological departments. Therefore, we advise to refer patients to urological treatment as early as possible.

Sodium acetate prevents testicular damage in Wistar rats subjected to testicular ischaemia/reperfusion injury.

AIMS: The aim of this study was to investigate the potential antioxidant, anti-inflammatory, and sperm function-preserving properties of sodium acetate (ACE), a histone deacetylase (HDAC) inhibitor, in a rat model of testicular torsion/detorsion (T/D). MAIN METHODS: Littermate Wistar rats of identical weight were subjected to sham surgery or testicular T/D by rotating the left testis at 720° around its axis along the spermatic cord clockwise and fixing it in this position for two and a half hours. 1 h before detorsion, T/D + ACE-treated rats were treated with ACE (200 mg/kg/day, per os) while T/D rats were vehicle-treated by administering 0.5 mL of distilled water. After 72 h, animals were euthanized, and the left testes were harvested for bio-molecular and histological analysis. KEY FINDINGS: Acetate administration attenuated T/D-induced rises in serum and testicular HDAC and testicular xanthine oxidase, uric acid, MDA, GSSG, MPO, TNF-α, IL-1ß, IL-6, NFkB, HIF-1α, and VCAM-1. In addition, acetate treatment alleviated T/D-induced decline in sperm quality (count, motility, viability, and normal morphology) and testicular 3ß-HSD, 17ß-HSD, testosterone, GSH, GSH/GSSG, SOD, catalase, GPx, GST, Nrf2, and HO-1. Furthermore, acetate prevented T/D-distorted testicular histoarchitecture and spermatogenic germ cell loss. SIGNIFICANCE: Sodium acetate during the post-ischaemic phase of testicular T/D may be beneficial in preventing I/R injury and maintaining fertility.

Temporal dynamics of ocular torsion and vertical vergence during visual, vestibular, and visuovestibular rotations.

Ocular torsion and vertical divergence reflect the brain's sensorimotor integration of motion through the vestibulo-ocular reflex (VOR) and the optokinetic reflex (OKR) to roll rotations. Torsion and vergence however express different response patterns depending on several motion variables, but research on their temporal dynamics remains limited. This study investigated the onset times of ocular torsion (OT) and vertical vergence (VV) during visual, vestibular, and visuovestibular motion, as well as their relative decay rates following prolonged optokinetic stimulations. Temporal characteristics were retrieved from three separate investigations where the level of visual clutter and acceleration were controlled. Video eye-tracking was used to retrieve the eye-movement parameters from a total of 41 healthy participants across all trials. Ocular torsion consistently initiated earlier than vertical vergence, particularly evident under intensified visual information density, and higher clutter levels were associated with more balanced decay rates. Additionally, stimulation modality and accelerations affected the onsets of both eye movements, with visuovestibular motion triggering earlier responses compared to vestibular motion, and increased accelerations leading to earlier onsets for both movements. The present study showed that joint visuovestibular responses produced more rapid onsets, indicating a synergetic sensorimotor process. It also showed that visual content acted as a fusional force during the decay period, and imposed greater influence over the torsional onset compared to vergence. Acceleration, by contrast, did not affect the temporal relationship between the two eye movements. Altogether, these findings provide insights into the sensorimotor integration of the vestibulo-ocular and optokinetic reflex arcs.

Ventricular bigeminy associated with myocardial ischemia in a dog with a colonic torsion: a case report.

BACKGROUND: Ventricular bigeminy due to myocardial ischemia has been reported in humans as well as in canine patients with obstructive gastrointestinal diseases. This is the first case report of ventricular bigeminy in a dog with a colonic torsion that resolved after fluid resuscitation and restoration of myocardial perfusion. CASE PRESENTATION: An 11-year-old, male neutered mixed breed dog presented with a one day history of vomiting, tenesmus, and lethargy. Physical examination identified an irregular heart rhythm and intermittent pulse deficits. A ventricular arrhythmia represented by ventricular premature complexes (VPCs) organized in bigeminy, was appreciated on a 3-lead electrocardiogram (ECG) with a single lead (II) view. Abdominal radiographs confirmed a colonic torsion. Prior to anesthetic induction, ventricular bigeminy was non responsive to fentanyl or lidocaine. The patient was anesthetized and intravascular volume deficit was identified by dampened plethysmographic wave amplitude (plethysomographic variability), audible softening of the Doppler sound, and more pronounced pulse deficits. Fluid resuscitation was achieved with a combination of intravenous crystalloid and colloid fluid therapy comprising 7.2% hypertonic saline and 6% hetastarch. The patient's cardiac rhythm converted to normal sinus after fluid resuscitation. The colonic torsion was surgically corrected. The patient recovered well from anesthesia and was ultimately discharged from the hospital 5 days later. CONCLUSIONS: The present case report highlights that myocardial ischemia can lead to ventricular arrythmias, such as ventricular bigeminy. This is the first documented case of ventricular bigeminy in the canine patient with a colonic torsion. Assessment of patient volume status and appropriate fluid resuscitation along with continuous electrocardiogram (ECG) monitoring are vital to patient stability under general anesthesia.

Validity and reliability of ultrasonographic assessment of femoral and tibial torsion in children and adolescents: a systematic review.

Torsional disorders of the lower limb are common in childhood, and they are one of the primary reasons parents seek consultation with healthcare providers. While clinical manoeuvres can assess femoral and tibial torsion, their reliability is medium to low. Various imaging-based techniques, including computed tomography, magnetic resonance imaging, fluoroscopy, biplanar radiology and ultrasonography, have been used to evaluate torsional alterations of the lower extremity. Among these, ultrasound assessment offers certain advantages: it is a low-cost, non-irradiating technique, which allows the follow-up of children's torsional development. However, to the best of the authors' knowledge, its validity and reliability have not been summarised in a systematic review. This study aims to analyse the validity and reliability of ultrasonography in determining femoral and tibial torsion in children and adolescents. A search from Medline (via PubMed), Web of Science, Scopus and CINAHL databases were performed from inception to 16 March 2023. No restrictions were placed on the publication year or language. The methodological quality of all eligible studies was independently reviewed by two authors using QUADAS and STARD checklists. Overall, 1546 articles were identified through the searches; 30 were considered eligible for full-text screening; and 8 studies were finally included in this review. The included studies were conducted in Germany, Norway and the UK. Among them, 7 studies analysed the validity of ultrasonography compared with other imaging techniques such as computed tomography, magnetic resonance imaging and biplanar X-ray, and 4 studies assessed intra- and inter-observer reliability. All the studies assessed femoral torsion, but only one of them also included tibial torsion.     Conclusion: Ultrasound is a good alternative for routine evaluation and follow-up of femoral torsional alterations in children and adolescents due to its safety, accessibility and immediate results in the clinical examination room. Although ultrasound has good accuracy and reliability for routine evaluations, there is controversy about whether it is sufficient for surgical planning. In cases where greater accuracy is required, magnetic resonance imaging and biplanar radiography are the preferred imaging techniques. What is Known: • Several imaging-based techniques have been described for the assessment of torsional alterations of the lower extremity. • Computed tomography, magnetic resonance imaging, biplanar radiology and ultrasonography are the most used and studied methods. What is New: • Ultrasonography represents a good alternative for the assessment of femoral and tibial torsional alterations in children and adolescents, given its safety, accessibility and immediacy of results in the consultation room. • Its accuracy and reliability are good but not sufficient for surgical planning, in which case MRI and biplanar X-ray will be the preferred choices.

Clinical characteristics and outcome of children with acute cryptorchid testicular torsion: A single-center, retrospective case series study.

BACKGROUND: Cryptorchidism and testicular torsion (TT) are relatively common conditions in clinical practice; however, sparse information about cryptorchid TT is available in the current literature. METHODS: We retrospectively reviewed the clinical characteristics, treatment modalities, and long-term outcomes of pediatric patients treated for acute cryptorchid TT. RESULTS: We found eight patients with unilateral acute cryptorchid TT with a prevalence of 8.9% (8/90) among all TT cases. The left testis was affected in six patients. The median age of patients at the time of the surgery was 65 months (interquartile range (IQR) 4-136 months). The median duration of symptoms was 16 h (IQR 9-25 h), while the median time to treatment was 60 min (IQR 59-63 min). The most common symptoms were pain (abdominal and inguinal) and inguinal mass with no palpable testis in the ipsilateral hemiscrotum. Preoperative color Doppler ultrasonography revealed absent or decreased testicular blood flow in the affected testes in 7/8 of patients. Various degrees of testicular torsion (median 540°, min 360°, max 1260°) were found during surgery. A necrotic testis that led to orchidectomy was found in 4/8 of patients. The median follow-up period was 42.6 months (IQR 12.5-71.2 months), revealing only one patient with testicular atrophy. The final testicular salvage rate was 35%. CONCLUSIONS: Greater awareness among caregivers and primary care physicians about acute cryptorchid TT is required to improve their timely diagnosis and treatment. A physical examination of the external genitalia and inguinal regions should be mandatory to attain a proper diagnosis and treatment without delay.

Evaluation of effects of Tempol on testicular ischemia/reperfusion injury.

AIM: Tempol, a synthetic antioxidant compound, has received significant attention for its potential therapeutic applications in recent years, especially against ischemia/reperfusion (I/R) injury. The aim of the present research was to assess the protective effects of Tempol on testicular I/R injury caused by testicular torsion and detorsion (T/D) in rats. METHODS: The subjects were divided into five groups: sham, testicular T/D, testicular T/D with Tempol treatment at 50 and 100 mg/kg, and healthy rats treated with Tempol at 100 mg/kg. Testicular torsion was induced by rotating the left testicles for 2 h, followed by detorsion for 24 h. Testicular tissues were evaluated for gene expression, oxidative stress markers, and histopathology, epididymal sperms were stained and analyzed, and blood serum samples were collected to measure the testosterone hormone. RESULTS: The results showed that testicular I/R caused a significant decrease in sperm velocity parameters, viability, and count, as well as an increase in abnormal sperms (p < 0.05). However, treatment with Tempol significantly improved these parameters (p < 0.05). Histopathological analysis revealed severe damage to the testicular tissues, but treatment with Tempol improved the structural integrity of the seminiferous tubules. Testicular I/R also resulted in increased oxidative stress index and decreased testosterone levels significantly (p < 0.05), but Tempol administration mitigated these effects significantly (p < 0.05). Furthermore, the expression of Bax and Bcl2, genes associated with apoptosis, were significantly altered by testicular I/R (p < 0.05), but Tempol prevented these changes significantly (p < 0.05). CONCLUSION: These findings provide strong evidence that Tempol can effectively prevent testicular I/R injury.

Ovarian torsion masquerading as a ureteral stone.

BACKGROUND: Abdominal pain is the most common complaint within the emergency department (ED) and has many varied etiologies. Some of these conditions can be medical emergencies, including ovarian torsion. While representing just 3% of gynecologic emergencies, ovarian torsion should be considered in all females presenting to the ED with abdominal or pelvic complaints. CASE: A 38-year-old G5P5 female with a past medical history significant for ureterolithiasis presented to a freestanding ED with abdominal pain, nausea, and vomiting. She developed sudden onset of right sided abdominal pain radiating to her right flank upon awakening. The initial differential diagnosis was for ureterolithiasis or appendicitis. Her complete blood count (CBC) was normal, and testing for pregnancy, infection, and hematuria was negative. Computed topography (CT) imaging of the abdomen and pelvis revealed a 9 cm adnexal mass, consistent with a possible dermoid cyst. A pelvic ultrasound was ordered which showed a possible ovarian torsion. She was transferred to a tertiary care hospital where she had a laparoscopy with right-sided oophorectomy and salpingectomy performed. DISCUSSION: This patient presented with abdominal pain, nausea, and vomiting and was first suspected to have ureterolithiasis or appendicitis. She was found to have an ovarian torsion with a dermoid cyst, which resulted in the loss of her ovary and fallopian tube. This case demonstrates the importance of including gynecologic emergencies in the differential on all female patients presenting with abdominal pain.

Spleno-Sigmoid Knotting - An Unfamiliar Cause of Intestinal Obstruction.

INTRODUCTION: Spleno-sigmoid knotting is the twisting of the spleen around the sigmoid colon, causing obstruction of the sigmoid colon. It is an uncommon cause of intestinal obstruction. To our knowledge, there has been no previous case report of spleno-sigmoid knotting before our case. CASE REPORT: Here, we present the case of an 18-year-old female patient who visited the surgical emergency outpatient department with diffuse and progressive abdominal pain lasting for one and a half days. She also experienced obstipation and frequent episodes of vomiting of ingested matter. Upon initial evaluation, she exhibited tachycardia and tachypnea, and her abdomen was grossly distended with diffuse direct and rebound tenderness. Further investigation revealed significant leukocytosis with neutrophil predominance. Emergency laparotomy was performed with a possible diagnosis of generalized peritonitis secondary to gangrenous sigmoid volvulus, which revealed gangrenous spleno-sigmoid knotting. DISCUSSION: Various types of intestinal knots have been reported, with ileo-sigmoid knots being the most common and ileo-ileal knots being the rarest. Wandering spleen is a rare congenital anomaly with a variable clinical presentation ranging from asymptomatic to mild abdominal pain or acute abdomen due to torsion or acute pancreatitis. It can also cause intestinal obstruction, which may be the initial presentation. CONCLUSION: In patients presenting with acute abdominal pain and features of bowel obstruction, the possibility of spleno-sigmoid knotting should be considered, and early intervention should be instituted to prevent gangrenous progression and sepsis.

Use of Indocyanine Green to Evaluate Ovarian Perfusion After Laparoscopic Detorsion. A Step-By-Step Demonstration Video.

OBJECTIVE: Demonstrate the usefulness of using indocyanine green after laparoscopic ovarian detorsion to save the ovary. DESIGN: A step-by-step video demonstration of a surgical technique. SETTING: Ovarian torsion is one of the most common gynecological emergencies, mainly affecting patients younger than 20 years of age [1], and causes 2% to 7% of acute abdomens [2]. It is not advisable to routinely perform ovariectomy even with a necrotic ovary appearance [1]. Furthermore only in a small percentage of cases (16%) necrosis has been confirmed histologically [2]. Some studies have demonstrated that using indocyanine green to evaluate ovarian perfusion is inexpensive, low risk, and easily reproducible [3-5]. INTERVENTIONS: A 17-year-old patient was referred to our hospital for acute abdominal pain. Ultrasound revealed ovarian torsion; therefore, the patient underwent surgical treatment. During laparoscopy, the presence of a right ovarian torsion was confirmed. A lesion compatible with a hemorrhagic corpus luteum of 6 cm was present on the ovary affected. Before ovarian detorsion, indocyanine green was administered intravenously at a 0.5 mg/kg dose. The first aspect noted was the total lack of ovarian vascularization; then ovarian detorsion was performed. At this point, using technology of Rubina (KARL STORZ SE & Co. KG, Tuttlingen, Germany), it was possible to highlight the progressive ovarian revascularization. Ovarian reperfusion occurred starting from the ovarian hilum and ending at the periphery. We proceeded with enucleation of the hemorrhagic corpus luteum by stripping technique, with subsequent ovarian reconstruction with continuous 2-0 monofilament suture. Finally, we fixed the ovary to the stump of the right round ligament. The final view highlights good ovarian vascularization. No complications occurred; the patient was discharged on the first postoperative day. A 6-month follow-up ultrasound confirmed the recovery of the vascularization of ovary. CONCLUSION: Using indocyanine green represents a valid option to evaluate ovarian perfusion after detorsion. It could help the surgeon decide to save the ovary and thus allow fertility-sparing surgery in more cases.

Neonatal Paratesticular Abscess as the Greatest Mimicker of Testicular Torsion.

INTRODUCTION: The management of acute scrotal swelling can be challenging in neonatal age, with scrotal abscess being great mimickers of testicular torsion. CASE PRESENTATION: We report a 12-day-old previously healthy male infant who presented with 72 h of increasing right-sided scrotal swelling, without fever or irritable behavior. The left testicle was palpable, but the right side was too swollen to palpate a testicle, with absent cremasteric reflex. Biochemical analysis was normal and Doppler sonography demonstrated a hypoechogenic avascular lesion compressing the right testis, without intratesticular flow. Due to these findings, surgical exploration was undertaken on suspicion of potential testicular torsion. Purulent material was encountered and cultured. The testis and epididymis were covered by thick necrotic fibrinous exudate, with no spermatic cord torsion. Gentamicin and vancomycin were begun immediately. The patient remained afebrile and the scrotal induration gradually subsided. Urine and blood cultures were sterile. On the second postoperative day, cultures yielded Escherichia coli sensitive to gentamicin. One-month follow-up testicular ultrasound demonstrated complete inflammation resolution. CONCLUSION: Paratesticular abscess may be considered as the greatest mimicker of testicular neonatal torsion, due to the frequent absence of classical signs of inflammation. Early surgical exploration can be diagnostic and therapeutic and should be performed in these cases.

Rapid, free-breathing non-contrast MRI for first-line imaging evaluation of ovarian torsion in the emergency department.

BACKGROUND: Transabdominal ultrasound (US) is first-line imaging to evaluate ovaries in girls presenting to the emergency department (ED) with suspected ovarian torsion. Ovaries may be difficult to visualize sonographically; therefore, prompt diagnosis using US alone can be challenging. Rapid MRI as first-line imaging may help streamline patient throughput, especially with increasing MRI availability in the ED. OBJECTIVE: To assess feasibility of rapid MRI for diagnosis of ovarian torsion. MATERIALS AND METHODS: A retrospective, single-center IRB approved study of MRI performed in female pediatric patients presenting with abdominopelvic pain from August 2022 to January 2023. Imaging occurred according to one of three clinical pathways (US-first approach vs MRI-first approach vs US + MRI-second-line approach). A rapid three-sequence free-breathing MRI protocol was utilized. Frequency of ovarian torsion and secondary diagnoses was recorded. Length of MR scan time, time from ED arrival to time of diagnosis, and whether patient had US prior to MR exam were obtained. A historical cohort of patients with US only performed for assessment of ovarian torsion were evaluated for length of the US examination and time from ED arrival to time of diagnosis. Intervals were compared using the uncorrected Fisher's least significant difference and Turkey's multiple comparison tests. RESULTS: A total of 140 MRI exams (mean age 14.6 years) and 248 historical US exams (mean age 13.5 years) were included. Of the patients with MRI, 41 (29%) patients were imaged with US + MRI and 99 (71%) imaged with MRI only; 4% (6/140) MR exams were suspicious for ovarian torsion, with one true positive case (1/6 TP) and 5 false positive cases (5/6 FP); 26.4% (37/140) of exams had secondary diagnoses. Median MRI scan time was 11.4 min (4.4) vs median historical US scan time was 24.1 min (19.7) (P<0.001). Median time from arrival in ED to MRI read was 242 (140). Median time from arrival in ED to US only read was 268 min (148). This was not a statistically significant difference when compared to the MRI only cohort. CONCLUSION: First-line MRI imaging for evaluation of ovarian torsion is a rapid and feasible imaging modality for female patients in the emergent setting.

Prenatal diagnosis of the umbilical cord torsion at the placental cord insertion site: A case report and literature review.

A 35-year-old woman (gravida 1, para 0) was admitted to our hospital at 28 weeks' gestation with vaginal bleeding from placenta previa. Severe fetal bradycardia was observed during fetal heart rate monitoring. Ultrasonography showed widely dilated veins on the fetal surface of the placenta and an extraordinarily low umbilical artery peak systolic velocity in the Doppler study. Umbilical cord torsion was suspected. On the subsequent day, we performed a cesarean section due to worsening fetal heart rate patterns. Umbilical artery blood gas analysis indicated severe acidemia (pH 7.063), and umbilical cord torsion was confirmed at the placental cord insertion site. Diagnosing UCT prenatally is challenging; however, it can be suspected by scanning for the widely dilated veins on the fetal placental surface, termed as the "Sunset Sign," an abnormally low umbilical artery peak systolic velocity, and other fetal Doppler abnormalities.

A nomogram for predicting risk factors of testicular salvage after testicular torsion in children.

OBJECTIVES: This study aimed to establish a nomogram for predicting the probability of testicular salvage after testicular torsion in children. METHODS: We retrospectively collected data of children with testicular torsion who were treated at Shenzhen Children's Hospital between September 2005 and August 2022. Of the training cohort, 113 patients who underwent orchiectomy and five with testicular atrophy after orchiopexy were included in the failed testicular salvage group. Additionally, 37 patients who underwent orchiopexy without postoperative testicular atrophy were included in the successful testicular salvage group. The predictive factors affecting testicular salvage were determined using univariate and multivariate logistic regression analyses; a nomogram was constructed. The nomogram was verified using data from the validation group. RESULTS: Using multivariate logistic regression analysis, the independent risk factors of testicular salvage after testicular torsion were symptom duration (p = 0.034), intratesticular blood flow (p = 0.003), spermatic cord torsion degree (p = 0.037), and monocyte count (odds ratio: 0.012, p = 0.036). A nomogram was established based on these four risk factors. In the training cohort, the area under the receiver operating characteristic curve was 0.969. The area under the receiver operating characteristic curve of the verification cohort was 0.965, indicating good discrimination ability of the nomogram. Increased symptom duration without intratesticular blood flow increased the monocyte count and spermatic cord torsion degree and decreased the success rate of testicular salvage. CONCLUSION: This prediction model could obtain the corresponding probability of testicular salvage according to the clinical characteristics of different patients with testicular torsion, providing reference for clinicians and parents.