Responses of Five Different Artificial Intelligence Chatbots to the Top Searched Queries About Erectile Dysfunction: A Comparative Analysis.

The aim of the study is to evaluate and compare the quality and readability of responses generated by five different artificial intelligence (AI) chatbots-ChatGPT, Bard, Bing, Ernie, and Copilot-to the top searched queries of erectile dysfunction (ED). Google Trends was used to identify ED-related relevant phrases. Each AI chatbot received a specific sequence of 25 frequently searched terms as input. Responses were evaluated using DISCERN, Ensuring Quality Information for Patients (EQIP), and Flesch-Kincaid Grade Level (FKGL) and Reading Ease (FKRE) metrics. The top three most frequently searched phrases were "erectile dysfunction cause", "how to erectile dysfunction," and "erectile dysfunction treatment." Zimbabwe, Zambia, and Ghana exhibited the highest level of interest in ED. None of the AI chatbots achieved the necessary degree of readability. However, Bard exhibited significantly higher FKRE and FKGL ratings (p = 0.001), and Copilot achieved better EQIP and DISCERN ratings than the other chatbots (p = 0.001). Bard exhibited the simplest linguistic framework and posed the least challenge in terms of readability and comprehension, and Copilot's text quality on ED was superior to the other chatbots. As new chatbots are introduced, their understandability and text quality increase, providing better guidance to patients.

Central tolerance shapes the neutralizing B cell repertoire against a persisting virus in its natural host.

Viral mimicry of host cell structures has been postulated to curtail the B cell receptor (BCR) repertoire against persisting viruses through tolerance mechanisms. This concept awaits, however, experimental testing in a setting of natural virus-host relationship. We engineered mouse models expressing a monoclonal BCR specific for the envelope glycoprotein of lymphocytic choriomeningitis virus (LCMV), a naturally persisting mouse pathogen. When the heavy chain of the LCMV-neutralizing antibody KL25 was paired with its unmutated ancestor light chain, most B cells underwent receptor editing, a behavior reminiscent of autoreactive clones. In contrast, monoclonal B cells expressing the same heavy chain in conjunction with the hypermutated KL25 light chain did not undergo receptor editing but exhibited low levels of surface IgM, suggesting that light chain hypermutation had lessened KL25 autoreactivity. Upon viral challenge, these IgMlow cells were not anergic but up-regulated IgM, participated in germinal center reactions, produced antiviral antibodies, and underwent immunoglobulin class switch as well as further affinity maturation. These studies on a persisting virus in its natural host species suggest that central tolerance mechanisms prune the protective antiviral B cell repertoire.

Unusual Presence of Synchronous Primary Ovarian and Thyroid Extranodal Non-Hodgkin Lymphoma Without Lymph Node Involvement.

ABSTRACT: Extranodal lymphomas without lymph node involvement are rarely observed and create diagnostic challenges. We present the case of a 33-year-old woman who was admitted with abdominal swelling. Ultrasonography findings suggested bilateral ovarian masses. 18 F-FDG PET/CT revealed intense uptake on the bilateral pelvic mass and thyroid gland. Following excisional surgery and thyroid fine-needle aspiration biopsy, the patient was diagnosed with diffuse large B-cell lymphoma. This case is exceptionally rare, as it presents 2 synchronous extranodal involvements in the ovaries and the thyroid gland independently while not presenting any lymph node activity, which has not been reported before.

Predictive Value of the Naples Prognostic Score on Long-Term Outcomes in Patients with Peripheral Artery Disease Revascularized via Percutaneous Intervention.

BACKGROUND: Lower extremity peripheral artery disease (PAD) is the third most common clinical manifestation of atherosclerosis after coronary artery disease and stroke. Despite successful endovascular treatment (EVT), mortality and morbidity rates still remain higher in patients with PAD. Naples prognostic score (NPS) is a novel scoring system, reflects the patient's nutritional and immunological statuses as well as systemic inflammatory responses. In this study, we aimed to investigate the relationship between NPS and long-term outcomes in patients with PAD. METHODS: The population of this retrospective study consisted of 629 PAD patients who underwent EVT at Kafkas University Hospital between 2020 and 2023. For each patient, the NPS was calculated and then patients were divided into 3 groups based on their NPS. The primary end point of the study was the rate of major adverse cardiovascular (MACEs) and limb events (MALEs), that is, all-cause death or development of critical limb ischemia with consequent amputation. RESULTS: Of a total of 629 patients, 62 were classified into group 0 (NPS 0), 315 into group 1 (NPS 1 or 2), and 252 into group 2 (NPS 3 or 4). The distribution of patients' baseline characteristics, angiographic features and MACEs and MALEs according to the NPS groups was analyzed. Significant adverse outcomes differences were observed among the 3 groups (P < 0.001). Multivariate logistic regression analysis revealed that age, diabetes mellitus, chronic kidney disease, lowest preprocedure ankle-brachial index, left ventricular ejection fraction and NPS (hazard ratio 1.916, 95% confidence interval [CI] 1.530-2.398, P < 0.001) were independent predictors of MACE whereas diabetes mellitus, presence of previous PAD, hemoglobin level, in-hospital acute thrombotic occlusion and NPS (odds ratio 1.963, 95% CI 1.489-2.588, P < 0.001) were independent predictors of MALE. CONCLUSIONS: The inflammatory and nutritional state reflected by NPS levels was strongly associated with all-cause mortality and amputation after EVT in patients with PAD. Furthermore, NPS was found to be an independent predictor of these clinical outcomes.

Intimal Hemorrhage of Basilar Artery Induced by Severe Vasospasm Following Subarachnoid Hemorrhage: The Experimental Analysis.

BACKGROUND: Cerebral vasospasm, a serious complication of subarachnoid hemorrhage (SAH), has been extensively studied for its neurochemical and pathophysiological mechanisms. However, the contribution of inner elastic membrane dissection and subintimal hemorrhage to basilar artery occlusion remains underexplored. This study investigates inner elastic membrane-related changes in the basilar artery after SAH. METHODS: Twenty-four hybrid rabbits were divided into control, sham, and SAH groups, with SAH induced by autologous blood injection. After two weeks, basilar artery changes, vasospasm indexes (VSI), and dissections were evaluated. RESULTS: The SAH group showed significantly higher VSI, with vascular wall thickening, luminal narrowing, convoluted smooth muscle cells, intimal elastic membrane disruption, endothelial cell desquamation and apoptosis. Some SAH animals exhibited subintimal hemorrhage, inner elastic membrane dissection, and ruptures. Basilar arteries with subintimal hemorrhage had notably higher VSI. CONCLUSIONS: These findings highlight the role of subintimal hemorrhage and inner elastic membrane dissection in basilar artery occlusion post-SAH, offering valuable insights into vasospasm pathophysiology.

Analysis of thoracic trauma patients transferred to Türkiye's largest hospital after Kahramanmaras earthquake.

BACKGROUND: On February 6, 2023, an earthquake in Türkiye caused massive destruction. Over 50.000 people are known to have lost their lives, and over 100.000 are known to have been maimed. In our study, we aimed to analyze the treatment process of 267 METHODS: The demographic characteristics, the time spent under the rubble, the duration of transfer to the hospital, and the treatment process of patients admitted to our hospital have been evaluated. RESULTS: There are 125 (46.8%) men and 142 (53.2%) women in the study. The rate of thoracic trauma was 21.8%. Of all the patients, 15.7% (n=42) had pneumothorax, 18% (n=48) had contusion, 28.8% (n=77) had hemothorax, and 73% (n=195) had rib fractures. The mean time spent under the rubble was 17.6±26.5 h, the duration of transfer to the hospital was 138.5±113.6 h, and the hospitalization time was 93.8±152.3 h. The duration of hospitalization and transfer has been statistically longer for the patients who were under the rubble (85.4%) than for those who were not. (14.6%) (p=0.048). There is a statistically weak positive correlation between the time spent under the rubble and the time of transfer (p=0.048). CONCLUSION: The state, the time spent under the rubble, and the presence of hemothorax and pneumothorax should be effectively evaluated in earthquake-induced thoracic traumas. Considering these criteria in the transfer of patients to the centers operating at full capacity in a short time will minimize morbidity and mortality.

Comparison of the 68 Ga-FAPI Versus 18 F-FDG in Gastric Adenocarcinoma and Anthracosis-Associated Lymph Nodes: FAPI Unmasking False-Negatives and False-Positives.

ABSTRACT: A 73-year-old woman with poorly differentiated gastric adenocarcinoma was referred to 18 F-FDG PET/CT for evaluation of the disease. FDG PET/CT showed intense uptake in the disseminated lymph nodes. However, there was no uptake in the primary tumoral lesion. Subsequently, 68 Ga-FAPI-04 PET/CT was performed with the decision of the tumor board and demonstrated intense uptake in the tumoral lesion. However, there was low or no uptake in disseminated lymph nodes. Tru-cut biopsy results revealed that all the lymph nodes were associated with anthracosis.

The impact of the right heart cavities echocardiographic features on atrial-high rate episodes.

Atrial high-rate episodes (AHRE) defined as atrial tachy-arrhythmias, detected through continuous monitoring with a cardiac implantable electronic device (CIED). AHRE's have been associated with increased risks of developing clinically manifested atrial fibrillation, thromboembolism, cardiovascular events, and mortality. Several variables have been researched and identified to predict AHRE existence. The present study evaluated the association between right-heart structural and functional echocardiographic parameters and AHRE in patients with CIEDs and impaired LVEF. This prospective design study included 194 patients with CIED's. The study population was divided into two groups according to presence of AHRE and analyzed the echocardiographic variables which may able to be a predictor of AHRE. Patients was divided into two groups: patients with AHRE (+) and without AHRE (-). The distribution of patients' characteristics according to presence of AHRE was analyzed. The multivariate analysis revealed Age, LAVI, E/Em tricuspid (HR: 1.106, 1.015-1.205% 95 CI; p = 0.022) and RAVI (HR: 1.035, 1.003-1.069 95% CI; p = 0.033) as independent predictors of AHREs. ROC curve analysis indicated that an E/Em tricuspid (AUC: 0.611, 95% CI 0.538-0.680 p: 0.009) and RAVI (AUC = AUC: 0.707, 95% CI 0.637-0.770 p < 0.001) predicted AHREs with a cut-off value of 6.28 and a sensitivity of 53.2% and specificity of 66.7% and a cut-off value of 29.5 mL/m2 with a sensitivity of 72.7% and a specificity of 65.9%, respectively. The main finding of this study was "RAVI" and "E/Emtricuspid ratio" is associated with AHRE. Additionally, "RAVI" and "E/Emtricuspid ratio" is an independent predictor of AHRE existence.

Overlooked evidence for transmission deficit of pupillary light reflex can be secondary to trigeminal nerve ganglion degeneration following subarachnoid hemorrhage; preliminary experimental study.

OBJECTIVE: Although the effect of oculomotor and cervical sympathetic networks on pupil diameter is well known; the effect of the trigeminal nerve on pupil diameter has not been investigated yet. This subject was investigated. MATERIALS AND METHODS: Five of 23 rabbits were used as a control group (GI; n = 5); 0.5 ccs saline solution into cisterna magna injected animals used as SHAM (GII; n = 5); autologous blood injected to produce SAH used as the study group (GIII; n = 13) and followed up three weeks. Light-stimulated pupil diameters were measured with an ocular tomography device before, middle, and at the end of the experiment. Considering the sclera area/pupil area ratio index (PRI) as the pupillary reaction area, we used this equation for the pupil's rush to light. Degenerated neuron densities of trigeminal ganglia and pupil diameters compared with the Mann-Whitney U test. RESULTS: The PRI, degenerated neuron density of trigeminal ganglia (n/mm3) were: (2.034 ± 0.301)/(13 ± 3) in GI; (1.678 ± 0.211)/(46 ± 9) in GII; and (0.941 ± 0.136)/(112 ± 21) in GIII. P-values between groups as: p < 0.005 in GI/GII; p < 0.0001 in GII/GIII and p < 0.00001 in GI/GIII. CONCLUSION: Light stimulates the cornea which is innervated by the trigeminal nerves. This experimental study indicates that the pupil remains mydriatic as the cornea is damaged by trigeminal ischemia following SAH and blocks the light flow.

Circumflex coronary artery revascularization at the proximal atrioventricular groove.

Proximal circumflex coronary artery in the atrioventricular groove usually has large diameters. Arterial diameters in this region vary from 2.5 to 5 mm. Revascularization of this part of the circumflex artery allows good distal anastomosis configuration and better long-term patency rate.

Stopping Microfluidic Flow.

A cross-comparison of three stop-flow configurations-such as low-pressure (LSF), high-pressure open-circuit (OC-HSF), and high-pressure short-circuit (SC-HSF) stop-flow-is presented to rapidly bring a high velocity flow O(m s-1 ) within a microchannel to a standstill O(µm s-1 ). The performance of three stop-flow configurations is assessed by measuring residual flow velocities within microchannels having three orders of magnitude different flow resistances. The LSF configuration outperforms the OC-HSF and SC-HSF configurations within a high flow resistance microchannel and results in a residual velocity of <10 µm s-1 . The OC-HSF configuration results in a residual velocity of <150 µm s-1 within a low flow resistance microchannel. The SC-HSF configuration results in a residual velocity of <200 µm s-1 across the three orders-of-magnitude different flow resistance microchannels, and <100 µm s-1 for the low flow resistance channel. It is hypothesized that residual velocity results from compliance in fluidic circuits, which is further investigated by varying the elasticity of microchannel walls and connecting tubing. A numerical model is developed to estimate the expanded volumes of the compliant microchannel and connecting tubings under a pressure gradient and to calculate the distance traveled by the sample fluid. A comparison of the numerically and experimentally obtained traveling distances confirms the hypothesis that the residual velocities are an outcome of the compliance in the fluidic circuit.

Changes in the Urethral Artery After Experimental Subarachnoid Hemorrhage-Induced Injury of the Pudendal Ganglion and Onuf's Nucleus Junction.

OBJECTIVE: Onuf's nucleus is an anatomical structure essential in the regulation of urogenital functions. Lumbosacral pathologies may cause changes in urogenital circulation due to Onuf's nucleus injury; however, there is limited evidence corroborating the relationship between spinal cord injury and urethral artery changes. MATERIALS AND METHODS: We used 23 sexually mature male rabbits-5 rabbits in the control group (GI), 5 rabbits in the sham group (GII), and 13 rabbits in the experimental group (GIII; received autologous blood transfusion into the T12-L1 subarachnoid space to induce subarachnoid hemorrhage (SAH). The GIII underwent a S1-3 laminectomy after 2 weeks and was decapitated. Histologic specimens were prepared to examine changes in Onuf's nucleus, pudendal ganglion, and urethral arteries. The density of damaged neurons and vasospasm index (VSI) in the urethral artery were evaluated. RESULTS: The mean density of damaged neurons (n/mm3 ) in Onuf's nucleus and pudendal ganglia (S3) and the mean VSI of the 3 groups were as follows-GI: 6 ± 2 per mm3 , 12 ± 4 per mm3 , and 1.63 ± 0.25, respectively; GII: 27 ± 6 per mm3 , 221 ± 62 per mm3 , and 1.97 ± 0.36, respectively; GIII: 154 ± 41 per mm3 , 1890 ± 541 per mm3 , and 3.04 ± 0.95 (P < .05 each for GI/GII, GI/GIII, and GII/GIII). Neuronal damage criteria, such as cytoplasmic condensation and cytoplasmic halo formation, were more prominent in GIII. CONCLUSION: SAH can lead to ischemia of the Onuf's nucleus-pudendal nerve structures due to urethral artery spasm, resulting in urogenital complications.

Low relapse rate in patients with giant cell arteritis in a multi-centre retrospective Turkish Registry.

OBJECTIVES: Glucocorticoids (GC) are widely accepted as the standard first-line treatment for giant cell arteritis (GCA). However, relapse rates are reported up to 80% on GC-only protocol arms in controlled trials of tocilizumab and abatacept in 12-24 months. Herein, we aimed to assess the real-life relapse rates retrospectively in patients with GCA from Turkey. METHODS: We assembled a retrospective cohort of patients with GCA diagnosed according to ACR 1990 criteria from tertiary rheumatology centres in Turkey. All clinical data were abstracted from medical records. Relapse was defined as any new manifestation or increased acutephase response leading to the change of the GC dose or use of a new therapeutic agent by the treating physician. RESULTS: The study included 330 (F/M: 196/134) patients with GCA. The mean age at disease onset was 68.9±9 years. The most frequent symptom was headache. Polymyalgia rheumatica was also present in 81 (24.5%) patients. Elevation of acute phase reactants (ESR>50 mm/h or CRP>5 mg/l) was absent in 25 (7.6%) patients at diagnosis. Temporal artery biopsy was available in 241 (73%) patients, and 180 of them had positive histopathological findings for GCA. For remission induction, GC pulses (250-1000 methylprednisolone mg/3-7 days) were given to 69 (20.9%) patients, with further 0.5-1 mg/kg/day prednisolone continued in the whole group. Immunosuppressives as GC-sparing agents were used in 252 (76.4%) patients. During a follow-up of a median 26.5 (6-190) months, relapses occurred in 49 (18.8%) patients. No confounding factor was observed in relapse rates. GC treatment could be stopped in only 62 (23.8%) patients. Additionally, GC-related side effects developed in 64 (24.6%) patients, and 141 (66.2%) had at least one Vasculitis Damage Index (VDI) damage item present during follow-up. CONCLUSIONS: In this first multi-centre series of GCA from Turkey, we observed that only one-fifth of patients had relapses during a mean follow-up of 26 months, with 76.4% given a GC-sparing IS agent at diagnosis. At the end of follow-up, GC-related side effects developed in one-fourth of patients. Our results suggest that patients with GCA had a low relapse rate in real-life experience of a multi-centre retrospective Turkish registry, however with a significant presence of GC-associated side effects during follow-up.

Identification of immune-related candidate biomarkers in plasma of patients with sporadic vestibular schwannoma.

Vestibular schwannoma (VS) is an intracranial tumor arising from neoplastic Schwann cells and typically presenting with hearing loss. The traditional belief that hearing deficit is caused by physical expansion of the VS, compressing the auditory nerve, does not explain the common clinical finding that patients with small tumors can have profound hearing loss, suggesting that tumor-secreted factors could influence hearing ability in VS patients. We conducted profiling of patients' plasma for 66 immune-related factors in patients with sporadic VS (N > 170) and identified and validated candidate biomarkers associated with tumor size (S100B) and hearing (MCP-3). We further identified a nine-biomarker panel (TNR-R2, MIF, CD30, MCP-3, IL-2R, BLC, TWEAK, eotaxin, and S100B) with outstanding discriminatory ability for VS. These findings revealed possible therapeutic targets for VS, providing a unique diagnostic tool that may predict hearing change and tumor growth in VS patients, and may inform the timing of tumor resection to preserve hearing.

A case report of giant malignant schwannoma of the sciatic nerve associated with neurofibromatosis-1: A CARE-compliant article.

RATIONALE: Neurofibromatosis type 1 (NF1) is an autosomal dominant neurocutaneous syndrome that causes multiple central and peripheral nerve sheath tumors. People with NF1 have a 10% chance of developing malignant peripheral nerve sheath tumors (MPNSTs). Here we report a unique instance of a malignant schwannoma that has remained free of metastasis since its initial removal a decade ago. The malign schwannoma has been infrequently documented in the literature, and remarkably, no instances of such an extensive postoperative time without metastases have ever been described. PATIENT CONCERNS: A 46-year-old male patient with NF had multiple neurofibromas in different parts of his body, underwent surgery about 10 years ago (2013), and was diagnosed histopathologically as MPNST. DIAGNOSES: He was admitted to our institution with a recurrent mass in the posterior third of the proximal thigh and severe pain radiating to the left lower extremity, which presented as sciatic pain (2021). A magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography examination revealed that the tumor was likely malignant. INTERVENTIONS: Surgical excision was performed. OUTCOME: A 10-year follow-up revealed no metastases or neurologic impairment. LESSONS: When articles about benign schwannomas are placed in a separate category, little is written about NF-1-related malignant schwannomas of the sciatic nerve. MPNSTs are high-grade, aggressive sarcomas with a high risk of local recurrence (40%-65%) and metastasis to other body parts. Therefore, among the various benign peripheral nerve sheath tumors in NF-1 patients, the diagnosis of MPNST is crucial.Orthopedic surgeons should be aware that neurofibromas in NF-1 have a significant risk of developing MPNSTs. This study reports the successful treatment of a giant malignant sciatic nerve schwannoma with a long follow-up period without metastasis.

Effect of preoperative single-dose methylprednisolone administration on early postoperative pain following retrograde intrarenal surgery.

PURPOSE: To evaluate the effect of preoperative single-dose methylprednisolone use on postoperative early pain after retrograde intrarenal surgery (RIRS). METHODS: Patients who had 10-20 mm solitary kidney stones and underwent RIRS procedures were included in this prospective cohort study between February 2022 and May 2023. Patients who were administered methylprednisolone at a dose of 1 mg/kg preoperatively were included in group 1 (n: 31), and the other first 90 patients who met the inclusion criteria and did not receive methylprednisolone before surgery were included in group 2 (n: 90). Demographic data, features of stone, postoperative pain at 1, 6, 12, 18, and 24 hour, the need for analgesics, changes in serum glucose levels, and the prevalence of postoperative fever were compared. RESULTS: Age, sex, stone laterality, localization, size, Hounsfield Unit, modified Satava scores, stone-free status, duration of the RIRS procedure, and duration of the ureteral access sheath were found to be similar between groups. Visual Analog Scale (VAS) scores at postoperative 1, 6, 12, 18, and 24 h were found to be statistically significantly lower in group 1 (p = .001, p = .001, p = .001, p = .001, and p = .001, respectively). Similarly, postoperative analgesic requirements were found to be significantly lower in group 1 (p = .048) with a similar postoperative fever rate and changes in serum glucose levels between groups. CONCLUSION: Giving a single dose of methylprednisolone at a dose of 1 mg/kg preoperatively for the RIRS procedure is safe and effective at preventing early pain and the need for analgesics after the RIRS procedure.

The Predictive Factors for the Longer Survival of the Reusable Flexible Ureterorenoscopy.

PURPOSE: The flexible ureterorenoscopy (FURS) is expensive and fragile equipment which easily break down during the surgery. f-URS have yet some problems with their durability that affect survival. One of the most important ways to increase the survival of a device is to improve its use in the right indications. We aimed to investigate whether the durability of the f-URS will be affected due to the volume and location of the stone and some anatomical features of the including infundibulopelvic angle (IPA), and location anomalies. MATERIALS AND METHODS: The collected data from 705 patients' data including their age, sex, stone location, and stone volume, S-ReSC score, Hounsfield unit (HU) as stone density, IPA, BMI, and the usage time of f-URS using 10f-URS were included to study. Exp(B) values and confidence intervals (95% CIs) of parameters were calculated with COX regression and Roc curve analysis was also used to determine the cut-off value. RESULTS: Renal malformation, DJstent use, previous ESL application, and UAS use did not affect contrary to expectations stone volume, HU, IPA, and S-ReSC score were among the factors statistically significant affecting the durability of the device. It was observed, Exp(B) values of the affecting factors to be 0.984, 0.268, 0.894, and 0.607, respectively. We found the most appropriate cutoff value for IPA as 41.25 degrees. CONCLUSION: The mean stone volume broken by each of the subsequent f-URS may increase, while the mean operative time may decrease as time progresses. This result shows us the importance of mastery of the device, such as the deflection maneuver, and the correct use distance of the laser, which improves with the increase in user experience, and makes us interpret that the operation time is shortened with this self-confidence. Factors including stone volume, HU, IPA, S-ReSC score affect the durability of the f-URS device and the as well as manufacturing features.

Predestinative role acidic cerebrospinal fluid on the destiny of central channel in spinal cord following subarachnoid hemorrhage: an experimental study.

OBJECTIVE: Acidosis is the most dangerous complication in subarachnoid hemorrhage (SAH). This study aimed to investigate the effect of acidic cerebrospinal fluid on central canal structures after SAH. MATERIALS AND METHODS: Twenty-eight hybrid rabbits were studied. Blood and cerebrospinal fluid pH values were recorded before/during/after the experimental procedures. The structures related to the central canals at the level of C5 of the cervical spinal cord were then examined histopathologically. The relationship between pH values of ependymal cells and degenerated epithelial cell densities was statistically analyzed. RESULTS: Mean blood pH values and degenerated ependymal cell density (n/mm2) were as follows: 7.351 ± 0.033/23 ± 7 in control, 7.322 ± 0.059/78 ± 13 in SHAM, and 7.261 ± 0.048/254 ± 62 in study animals. Gross examinations revealed swelling, edema, pia-arachnoid adhesions, ventral canal dilatation, arachnoiditis, central canal hemorrhage, occlusions, and dilatation in the spinal cord. CONCLUSION: Cerebrospinal fluid acidosis-induced central channel pathologies should be considered an important complication of SAH following SAH.

OBJETIVO: La acidosis es la complicación más peligrosa en la hemorragia subaracnoidea (HSA). El objetivo de este estudio fue investigar el efecto del líquido cefalorraquídeo ácido en las estructuras del canal central tras la HSA. MATERIALES Y MÉTODOS: Se estudiaron 28 conejos híbridos. Se registraron los valores de pH de la sangre y del líquido cefalorraquídeo antes, durante y después de los procedimientos experimentales. A continuación se examinaron histopatológicamente las estructuras relacionadas con los canales centrales a nivel de C5 de la médula espinal cervical. Se analizó estadísticamente la relación entre los valores de pH de las células ependimarias y las densidades de células epiteliales degeneradas. RESULTADOS: Los valores medios de pH en sangre y la densidad de células ependimarias degeneradas (n/mm2) fueron los siguientes: 7.351 ± 0.033/23 ± 7 en el control, 7.322 ± 0.059/78 ± 13 en el SHAM, 7.261 ± 0.048/254 ± 62 en los animales del estudio. Los exámenes macroscópicos revelaron hinchazón, edema, adherencias pia-aracnoideas, dilatación del canal ventral, aracnoiditis, hemorragia del canal central, oclusiones y dilatación en la médula espinal. CONCLUSIONES: Las patologías del canal central inducidas por la acidosis del líquido cefalorraquídeo deben considerarse como una complicación importante de la HSA tras una hemorragia subaracnoidea.

Single hybrid population but multiple parental individuals at the origin of parthenogenetic rock lizards Darevskia sapphirina and D. bendimahiensis Schmidtler, & Eiselt Darevsky (1994) endemic to the area of Lake Van in East Turkey.

Among vertebrates, obligate parthenogenesis is only found in Squamata, where it always has a hybrid origin and a few lizard genera contain most of the known hybridogenous parthenogenetic taxa. Parthenogenesis thus seems to be pre-conditioned at the genus level, but it is not clear how often the encounter between two parental sexually reproducing species can result in the parthenogenetic offspring, nor whether the success of such hybridization event requires certain conditions or the specific time frame. To address this question, we studied the rock lizards of genus Darevskia, where a pair of parental species, D. valentini and D. raddei, as well as their parthenogenetic daughter species D. bendimahiensis and D. sapphirina, are found in close proximity NE of the Lake Van in East Anatolia. Using ddRAD-seq genotyping on 19 parental and 18 hybrid individuals, we found that (i) all parthenogenetic individuals from both D. bendimahiensis and D. sapphirina have a monophyletic origin tracing back to a single initial hybrid population, but their current genetic variation is geographically structured; (ii) unlike the most probable paternal ancestor, the genetically closest extant population of the maternal ancestor is not the geographically nearest one; and (iii) in the parthenogens, about 1% of loci carry multiple haplotypes, frequently differentiated by multiple substitutions. This pattern, in addition to biases in the relative frequency of haplotypes of maternal and paternal origin, does not appear compatible with a scenario of the entire parthenogenic clonal population having descended from a single pair of parental individuals. Instead, the data suggest that multiple parental individual ancestries still persist in the parthenogenetic gene pool. This supports the notion that although hybridization leading to parthenogenesis is generally rare at the level of species, it may be more common at the individual/population level once the right conditions are met.