First Study of Antihyperon-Nucleon Scattering Λ[over ¯]p→Λ[over ¯]p and Measurement of Λp→Λp Cross Section.

Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes Λp→Λp and Λ[over ¯]p→Λ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψ→ΛΛ[over ¯] and the protons are the hydrogen nuclei in the cooling oil of the beam pipe. Clear signals are observed for the two reactions. The cross sections in -0.9≤cosθ_{Λ/Λ[over ¯]}≤0.9 are measured to be σ(Λp→Λp)=(12.2±1.6_{stat}±1.1_{syst}) and σ(Λ[over ¯]p→Λ[over ¯]p)=(17.5±2.1_{stat}±1.6_{syst}) mb at the Λ/Λ[over ¯] momentum of 1.074 GeV/c within a range of ±0.017 GeV/c, where the θ_{Λ/Λ[over ¯]} are the scattering angles of the Λ/Λ[over ¯] in the Λp/Λ[over ¯]p rest frames. Furthermore, the differential cross sections of the two reactions are also measured, where there is a slight tendency of forward scattering for Λp→Λp, and a strong forward peak for Λ[over ¯]p→Λ[over ¯]p. We present an approach to extract the total elastic cross sections by extrapolation. The study of Λ[over ¯]p→Λ[over ¯]p represents the first study of antihyperon-nucleon scattering, and these new measurements will serve as important inputs for the theoretical understanding of the (anti)hyperon-nucleon interaction.

Measurements of Normalized Differential Cross Sections of Inclusive η Production in e

Using data samples collected with the BESIII detector operating at the BEPCII storage ring, the cross section of the inclusive process e^{+}e^{-}→η+X, normalized by the total cross section of e^{+}e^{-}→hadrons, is measured at eight center-of-mass energy points from 2.0000 to 3.6710 GeV. These are the first measurements with momentum dependence in this energy region. Our measurement shows a significant discrepancy compared to the existing fragmentation functions. To address this discrepancy, a new QCD analysis is performed at the next-to-next-to-leading order with hadron mass corrections and higher twist effects, which can explain both the established high-energy data and our measurements reasonably well.

[Efficacy analysis of letrozole combined with gonadotropin-releasing hormone antagonists in patients with high risk of ovarian hyperstimulation syndrome undergoing total embryo freezing].

Objective: To investigate the clinical efficacy of letrozole combined with gonadotropin-releasing hormone antagonists (GnRH-ant) in patients at high risk of ovarian hyperstimulation syndrome (OHSS) who underwent total embryo freezing after oocyte retrieval. Methods: A retrospective analysis was conducted on 348 female patients who underwent in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) at the Reproductive and Genetic Hospital of the First Affiliated Hospital of Zhengzhou University between January and July 2023. Due to their high risk of OHSS, these patients canceled fresh embryo transfer and opted for total embryo freezing. Based on patients' preferences, those who received GnRH-ant and letrozole after oocyte retrieval were categorized as the intervention group (164 cases), while those who did not receive these medications were categorized as the control group (184 cases). The first luteal phase after oocyte retrieval, OHSS grading, ovarian volume, and estradiol (E2) levels were evaluated in both groups. A multivariate logistic regression model was used to analyze factors related to moderate-to-severe OHSS among patients at high risk of OHSS who underwent total embryo freezing after oocyte retrieval. Results: The age of the intervention and control groups was (29.3±3.8) and (29.4±4.1) years, respectively (P=0.821). The duration of the first luteal phase post-oocyte retrieval was shorter in the intervention group [(7.16±1.39) days] compared to that in the control group [(13.88±2.11) days] (P<0.001). The incidences of mild, moderate, and severe OHSS in the intervention group were 75.0% (123 cases), 23.8% (39 cases), and 1.2% (2 cases), respectively, whereas in the control group they were 12.5% (23 cases), 60.9% (112 cases), and 26.6% (49 cases) (P<0.001). E2 levels on the 2nd and 6th days after oocyte retrieval [M(Q1,Q3)] in the intervention group were 1 520.0 (1 213.8, 1 884.8) and 108.5 (45.6, 218.0) ng/L, respectively, which were statistically significantly lower than those in the control group [1 666.0 (508.8, 1 702.0) ng/L] and [1 761.0 (826.0, 2 546.5) ng/L] (P<0.001). The abdominal cavity effusion in the intervention group [M(Q1,Q3)] were 19.5 (0, 30) and 0 mm, statistically significantly less than those in the control group [46.0 (0, 61.0) mm] and [54.5 (0, 69.5) mm] (P<0.001). On the 6th day after oocyte retrieval, the bilateral ovarian volumes in the intervention group were smaller than those in the control group (P<0.001). Multivariate logistic regression analysis indicated that no combined treatment with letrozole and GnRH-ant was a risk factor of moderate to severe OHSS. The risk of developing moderate to severe OHSS in the control group was 35.312 times higher than that in the intervention group (OR=35.312, 95%CI: 17.488-71.300). Conclusions: The administration of letrozole combined with GnRH-ant post-oocyte retrieval in patients at high risk of OHSS can prevent the occurrence of moderate-to-severe OHSS, shorten the first luteal phase, accelerate the reduction of serum E2 levels, and promote the recovery of ovarian volume and absorption of abdominal fluid.

A pulsar in a binary with a compact object in the mass gap between neutron stars and black holes.

Some compact objects observed in gravitational wave events have masses in the gap between known neutron stars (NSs) and black holes (BHs). The nature of these mass gap objects is unknown, as is the formation of their host binary systems. We report pulsar timing observations made with the Karoo Array Telescope (MeerKAT) of PSR J0514-4002E, an eccentric binary millisecond pulsar in the globular cluster NGC 1851. We found a total binary mass of 3.887 ± 0.004 solar masses (M⊙), and multiwavelength observations show that the pulsar's binary companion is also a compact object. The companion's mass (2.09 to 2.71 M⊙, 95% confidence interval) is in the mass gap, indicating either a very massive NS or a low-mass BH. We propose that the companion formed in a merger between two earlier NSs.

Nontyphoidal Salmonella urinary tract infection in a case of hyperparathyroidism and nephrocalcinosis / Infección de las vías urinaria por Salmonella no tifoidea en un caso de hiperparatiroidismo y nefrocalcinosis

Nontyphoidal Salmonella infections often present with self-limited gastroenteritis. Extraintestinal focal infections are uncommon but have high mortality and morbidity. Urinary tract infection caused by nontyphoidal Salmonella is usually associated with structural abnormalities of the urinary tract. Nephrocalcinosis and nephrolithiasis are the major risk factors. Although primary hyperparathyroidism has been reported to increase the risk of nephrocalcinosis and nephrolithiasis, little is known about the association between hyperparathyroidism and Salmonella urinary tract infection. We report the case of a 37-year old man who had a history of primary hyperparathyroidism and bilateral nephrocalcinosis and who developed urinary tract infection. Salmonella Group D was isolated from his urine specimen. Salmonella should be considered as a possible causality organism in patients with primary hyperparathyroidism and nephrocalcinosis who develop urinary tract infection. These patients need to be aware of the potential risks associated with salmonellosis.

Las infecciones por Salmonella no tifoidea se presentan a menudo con gastroenteritis auto-limitada. Las infecciones extra-intestinales focales son poco frecuentes, pero tienen una alta mortalidad y morbilidad. La infección de las vías urinarias causada por la Salmonella no tifoidea se asocia generalmente a anomalías estructurales de las vías urinarias. La nefrocalcinosis y la nefrolitiasis son los principales factores de riesgo. Aunque se ha reportado que el hiperparatiroidismo primario aumenta el riesgo de la nefrocalcinosis y la nefrolitiasis, poco se sabe sobre la asociación entre el hiperparatiroidismo y la infección de las vías urinarias por Salmonella. Damos a conocer aquí el caso de un hombre de 37 años con una historia de hiperparatiroidismo primario y nefrocalcinosis bilateral, que desarrolló una infección de las vías urinarias. La Salmonella del grupo D fue aislada de su muestra de orina. La Salmonella se debe considerar como un posible organismo de causalidad en pacientes con hiperparatiroidismo primario y nefrocalcinosis que desarrollan infección del tracto urinario. Estos pacientes necesitan tomar conciencia de los riesgos potenciales asociados con la salmonellosis.

A School Outbreak of Shigella sonnei Infection in China: Clinical Features, Antibiotic Susceptibility and Molecular Epidemiology.

Objective: To describe the clinical features of infection, and the antibiotic susceptibility of epidemic strains, and investigate plasmid maps and integrons of the isolates from an outbreak of Shigella sonnei infection at an elementary school in southwest China. Study design: Cross-sectional study. Setting: An elementary school and five hospitals in Chengdu in southwest China. Results: There were 1,134 students in the school. 937 (82.6%) students had signs and symptoms. Of the 568 (60.6%, 568/937) hospitalized students, 93.3% 86.8%, 72.4%, and 28.9% of the hospitalized patients had diarrhea, fever, abdominal pain, and vomiting, respectively. S. sonnei strains were isolated from the stool samples of 36.0% (337/937) students. All of the outbreak isolates had the same high-level antimicrobial resistance and plasmid profiles, which were different from that of sporadic strains. All the outbreak S. sonnei isolates were positive for the integrin gene and contained class 2 integron; however, two outbreak isolates contained class 1 and class 2 integrons. Conclusions: Diarrhea, fever, and abdominal pain were the three most common clinical manifestations observed in patients infected with S. sonnei. High-level antibiotic resistance was observed among Shigella species.

Primary giant cell malignant fibrous histiocytoma of the kidney with staghorn calculi.

Malignant fibrous histiocytomas (MFH) as primary renal tumours are rare, with less than 50 cases described in the literature. We report a case of primary renal MFH of giant cell type in a 56-year-old man, who presented with bilateral dull flank pain, intermittent gross haematuria and body weight loss (6 kg in 3 months). Intravenous urography, computerized tomography (CT) and magnetic resonance image (MRI) showed right ureteral stones with mild hydronephrosis, and a solid mass at the lower pole of the left kidney associated with staghorn calculi, as well as tumour thrombi in the left renal vein and inferior vena cava. Left radical nephrectomy and evacuation of tumour thrombi from the left renal vein and inferior vena cava were performed. Histopathologic examination revealed malignant fibrous histiocytoma (MFH) of giant cell type. To the best of our knowledge, this is the first report of primary renal MFH associated with staghorn calculi.

Laparoscopic bilateral nephroureterectomy and bladder cuff excision for native renal pelvic and ureteral transitional cell carcinoma after renal transplantation.

A 37-years-old female who was suffering from end-stage renal disease for about 6 years received allograft renal transplantation 4 years ago. She has been receiving 50mg of Cyclosporin A orally daily for immuno-suppression since then. Gross haematuria was noted and computerised tomography showed native left renal pelvic and ureteral multi-focal transitional cell carcinoma with severe hydronephrosis. Laparoscopic bilateral nephroureterectomy and bladder cuff excision were performed. In the past, history of previous operation was considered a relative contraindication for laparoscopic surgery. To our knowledge, we present the first case of laparoscopic treatment for native renal pelvic and ureteral transitional cell carcinoma after renal allograft transplantation without a hand-assisted device. This case shows the feasibility of laparoscopic bilateral nephroureterectomy in patients with transplanted kidneys.