Mathematical models for sexually transmitted infections (STIs) are parameterised by empirical data on sexual behaviour (e.g. the number of partners over a given period) obtained from surveys.
View Article and Find Full Text PDFMonitoring time-varying vaccine effectiveness (e.g., due to waning of immunity and the emergence of novel variants) provides crucial information for outbreak control.
View Article and Find Full Text PDFAneurysmal subarachnoid hemorrhage (SAH) treatment has progressed, and patients are rapidly aging in Japan. Consequently, dynamic changes must have emerged in the clinical practice of SAH. This study aimed to elucidate chronological changes of aneurysmal SAH and the prognostic factors in the previous quarter century in Japan.
View Article and Find Full Text PDFMany countries affected by the global outbreak of mpox in 2022 have observed a decline in cases. Our mathematical model accounting for heavy-tailed sexual partnership distributions suggests that mpox epidemics can hit the infection-derived herd immunity threshold and begin to decline, with <1% of sexually active men who have sex with men infected regardless of interventions or behavioral changes. We consistently found that many countries and US states experienced an epidemic peak, with cumulative cases of around 0.
View Article and Find Full Text PDFThe outbreak of monkeypox across non-endemic regions confirmed in May 2022 shows epidemiological features distinct from previously imported outbreaks, most notably its observed growth and predominance amongst men who have sex with men (MSM). We use a transmission model fitted to empirical sexual partnership data to show that the heavy-tailed sexual partnership distribution, in which a handful of individuals have disproportionately many partners, can explain the sustained growth of monkeypox among MSM despite the absence of such patterns previously. We suggest that the basic reproduction number () for monkeypox over the MSM sexual network may be substantially above 1, which poses challenges to outbreak containment.
View Article and Find Full Text PDFCOVID-19 vaccine effectiveness against death in Japan remains unknown. Furthermore, although evidence indicates that healthcare capacity influences case-fatality risk (CFR), it remains unknown whether this relationship is mediated by age. With a modeling study, we analyzed daily COVID-19 cases and deaths during January-August 2021 by using Tokyo surveillance data to jointly estimate COVID-19 vaccine effectiveness against death and age-specific CFR.
View Article and Find Full Text PDFAssessing the impact of temperature on COVID-19 epidemiology is critical for implementing non-pharmaceutical interventions. However, few studies have accounted for the nature of contagious diseases, i.e.
View Article and Find Full Text PDFBackground: In Japan, a part of confirmed patients' samples have been screened for the variant of concern (VOC), including the variant alpha with N501Y mutation. The present study aimed to estimate the actual number of cases with variant alpha and reconstruct the epidemiological dynamics.
Methods: The number of cases with variant alpha out of all PCR confirmed cases was estimated, employing a hypergeometric distribution.
Background: Although carcinoma metastasis to primary intracranial neoplasms has occasionally been reported, metastasis to a cerebral arteriovenous malformation (AVM) has been exceedingly rare, with only 5 cases reported to date. In the present study, we have reported a case of lung carcinoma that had metastasized to a cerebral AVM. To the best of our knowledge, the present report is the first case in which the pathological examination detected the bleeding mechanism of this rare condition, showing destruction of the feeders by the metastatic tumor.
View Article and Find Full Text PDFBackground: Early and late images of I-iomazenil (I-IMZ) single-photon emission computed tomography (SPECT) are considered to show cerebral blood flow and neuronal activity, respectively, and this modality may demonstrate temporal dysfunction of the frontal lobes in obstructive hydrocephalus. In this report, we examined I-IMZ SPECT in a patient with chronic obstructive hydrocephalus owing to compression of the aqueduct by a partially thrombosed aneurysm of the left posterior cerebral artery for the first time.
Case Description: A woman aged 77 years presented with progression of cognitive decline, gait disturbance, and urinary incontinence.
Background: Intraoperative confirmation of the vascular anatomy and blood flow contributes to the safety of the surgery for perimedullary arteriovenous fistulas (PAVF). However, because the PAVF at the craniocervical junction (CCJ) is mainly located on the ventral spinal cord surface, it is difficult to observe the entire pathology by a conventional surgical approach. To achieve increased viewing angle and visualization of real time blood flow, we introduced endoscope-integrated fluorescein video angiography in the treatment for PAVF at the CCJ for the first time.
View Article and Find Full Text PDFObjective: Confirming the exact location of a fistula and the origins of draining veins during surgery for dural and perimedullary arteriovenous fistulas (AVFs) is crucial but sometimes inadequately performed, which can result in incomplete elimination of the lesion. Intraoperative digital subtraction angiography (DSA) is the gold standard for confirming the hemodynamics of an AVF; however, it cannot reveal the location of an AVF in the operative field. In this study, the efficacy of intraoperative intraarterial fluorescence video angiography during surgery for craniocervical junction dural and perimedullary AVFs was investigated.
View Article and Find Full Text PDFA copper/prolinol-phosphine chiral catalyst enabled the one-step synthesis of chiral α-alkylidene-β-lactams. Optimization of the chiral ligand for steric and electronic properties realized the highly enantioselective coupling of nitrones and propargyl alcohol derived alkynes. The resulting chiral α-alkylidene-β-lactams served as a platform for various β-lactams via well-established transformations of α,β-unsaturated carbonyl compounds.
View Article and Find Full Text PDFThe aim of this study is to clarify the details of distribution patterns of spinal epidural fluid and to establish it as measure of spontaneous intracranial hypotension (SIH) syndrome diagnosis. Magnetic resonance imaging findings of the spine were analyzed in 37 patients, 24 women and 13 men (mean age 46.3 years), with SIH.
View Article and Find Full Text PDFPhosphine organocatalysis enabled vicinal acylcyanation of alkynoates with acyl cyanides to form acrylonitrile derivatives with a tetrasubstituted alkene moiety. The acyl and cyano groups were introduced at the α and β carbon atoms, respectively, of the C-C triple bond in the alkynoates with complete regioselectivity and high anti stereoselectivity. A variety of functional groups in the acyl cyanides and alkynoates were tolerated.
View Article and Find Full Text PDFA Cu(I)-Xantphos system catalyzed the intramolecular hydroalkoxylation of unactivated terminal alkenes, giving five- and six-membered ring ethers. This system is applicable to both primary and secondary alcohols. A reaction pathway involving the addition of the Cu-O bond across the C-C double bond is proposed.
View Article and Find Full Text PDFBackground: To assess the degree of hepatic fat content, simple and noninvasive methods with high objectivity and reproducibility are required. Magnetic resonance imaging (MRI) is one such candidate, although its accuracy remains unclear. We aimed to validate an MRI method for quantifying hepatic fat content by calibrating MRI reading with a phantom and comparing MRI measurements in human subjects with estimates of liver fat content in liver biopsy specimens.
View Article and Find Full Text PDF