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In order to ensure the main mechanical properties of GH4096 alloy, reduce the internal residual stress of forgings for thin-walled parts and improve the dimensional control accuracy of parts machining, the effect of air cooling (AC), wind cooling (WC), oil cooling (OC) and salt bath cooling (SC) after solution heat treatment on the size, morphology of precipitated phase, mechanical properties and internal residual stress of GH4096 alloy ring forgings was studied. The results show that the secondary and tertiary γ′ phases of the air-cooled sample are coarser than those of the traditional oil-cooled sample, and the creep and high-temperature tensile properties are greatly reduced. The size of the secondary γ' phase is slightly increased, the size of the third γ' phase is equivalent of wind cooled sample, and the creep and high-temperature tensile properties are slightly reduced. The size of the secondary and tertiary γ' phase of the salt bath cooled sample is equivalent, so the difference of creep and high-temperature tensile properties is small. The residual stress in the samples by wind cooling could be controlled within ±100 MPa, which was more than 50% lower than that in the samples by oil cooling and salt bath cooling. The residual stress of the ring forgings by air cooling is lower than that of the ring forgings by oil cooling and salt bath cooling, and the main mechanical properties are only slightly reduced. It is helpful to improve the deformation of GH4096 alloy thin-walled parts during cold machining and improve the dimensional accuracy.

Taking the advanced aeroengine compressor blisk as the application object, the development and experimental study on the TC11/TC17 different materials linear friction welding integral blisk was carried out. The microstructure of welded joint was analyzed, the tensile and stress rupture properties of base metal and welded joint were compared, the vibration fatigue test on welded blade test pieces, and the overrunning test and low-cycle fatigue test on welding blisk were developed. The results show that the TC11/TC17 linear friction welding joint consists of five typical zones, they are TC11 base metal zone, TC11 thermal influence zone, weld zone, TC17 thermal influence zone and TC17 base metal zone. The tensile strength of the welded joint is basically equivalent to that of the TC11 base metal， elongation is equivalent to TC17 base metal; endurance strength lower than TC17 base metal, but less higher than TC11 base metal. The median fatigue life of welded blade test pieces with three weld positions is respectively 1.501 × 106, 0.344 × 106, and 0.132 × 106 cycles, the fatigue crack isn’t at welding seam and thermal influence zone. The welding blisk pass the 115% overrunning test and 1000 cycles low-cycle fatigue test, the experiment results meet the requirement.

Background: While spontaneous pneumothorax has been documented in COVID-19 patients, reports on recurrent spontaneous pneumothorax due to cystic lesions in convalescent COVID-19 patients are scarce. The progression of these lung cystic lesions remains inadequately explored. Case presentation and literature review: An 81-year-old male, a non-smoker with a history of rheumatoid arthritis, presented with fever, cough, and expectoration for 14 days. Initially diagnosed with moderate COVID-19, he deteriorated to severe COVID-19 despite adherence to local treatment guidelines. Successive identification of three cystic lesions termed "bulla" or "pneumatocele", and one cystic lesion with air-fluid level, referred to as "pneumo-hamatocele" (PHC), occurred in his lungs. Gradual improvement followed anti-inflammatory therapy and optimal supportive care. However, on day 42, sudden worsening dyspnea prompted a computed tomography (CT) scan, confirming a right spontaneous pneumothorax and subcutaneous emphysema, likely due to PHC rupture. Discharge followed chest tube implementation for pneumothorax resolution. On day 116, he returned to the hospital with mild exertional dyspnea. Chest CT revealed recurrent right pneumothorax from a remaining cyst in the right lung. Apart from our patient, literature retrieval identified 22 COVID-19 patients with spontaneous pneumothorax due to cystic lesions, with a male predominance (95.6%; 22/23). Diagnosis of pneumothorax and lung cystic lesions occurred around day 29.5 (range: 18–35) and day 26.4 (± 9.8) since symptom onset, respectively. Except for one patient whose pneumothorax occurred on day seven of illness, all patients eventually recovered. Conclusions: Recurrent spontaneous pneumothorax secondary to lung cystic lesions may manifest in convalescent COVID-19 patients, particularly males with COVID-19 pneumonia. Chest CT around 2 to 3 weeks post-symptom onset may be prudent to detect cystic lesion development and anticipate spontaneous pneumothorax. [ABSTRACT FROM AUTHOR]

Background. Amoxicillin was associated with acute generalized exanthematous pustulosis (AGEP), and the clinical characteristics were not clear. The purpose of this study was to explore the clinical characteristics of amoxicillin-induced AGEP and to provide a basis for prevention and treatment. Methods. Case reports and case series of amoxicillin-induced AGEP were collected for retrospective analysis by searching the Chinese and English databases from inception to January 31, 2023. Results. A total of 46 patients were included with a median age of 40 years (range 1.4, 87). The onset time of AGEP ranged from 6 hours to 28 days, with a median of 2.5 days. Fever occurred in 32 patients (69.6%), and pruritus occurred in 13 patients (28.3%). Ten patients (21.7%) had mucous membrane involvement and systemic involvement, respectively. Twenty-two patients had elevated neutrophils, with a median of 12850/mm3 (range 7880, 29140). Skin biopsy mainly showed subcorneal pustules (22 cases, 47.8%), spongy pustules (14 cases, 30.4%), and inflammatory cell infiltration (26 cases, 56.5%). Skin lesions disappeared in a median of 10 days (range 2, 42) after discontinuation of amoxicillin and administration of topical steroids (26 cases, 56.5%) as well as systemic corticosteroids (13 cases, 28.3%). Conclusions. AGEP is a rare complication of amoxicillin and is self-limiting. Clinicians should correctly identify AGEP and should avoid represcribing amoxicillin. Clinicians should correctly identify AGEP and avoid represcribing amoxicillin, which can prevent unnecessary treatment measures. [ABSTRACT FROM AUTHOR]

Myasthenia gravis (MG) is a rare but life-threatening adverse event with pembrolizumab. What is known about pembrolizumab-induced MG is largely based on case reports. This analysis collected pembrolizumab-induced MG cases from Chinese and English databases published from September 1, 2014, to June 30, 2022. Demographic and clinical information of the patients, management, and outcome data were collected and analyzed. Sixty-five patients with a median age of 73 years (range 30–86), including 43 male patients (66.2%), were included. Eight patients (12.3%) with prior MG experienced worsening symptoms after receiving pembrolizumab. The median time to the onset of MG was four weeks (range 0.7–27). The most common symptoms were ptosis (81.5%, 53 patients), diplopia (50.8%, 33 patients), dyspnea (44.6%, 29 patients), trunk or peripheral weakness (43.1%, 28 patients), and dysphagia (30.8%, 20 patients). Concurrent myositis and myocarditis occurred in 13 (20.0%) and 17 patients (26.2%). Pembrolizumab was discontinued in 63 patients (96.9%). Forty-four patients (67.7%) received combination therapies based on steroids (intravenous immune globulin, plasmapheresis, or immunosuppressants). Twenty-seven patients (41.5%) had symptoms completely recovered. Fourteen patients (21.5%) died from immunotoxicity or primary cancers. Clinicians should consider the possibility of pembrolizumab-induced MG, especially during the first eight weeks of therapy. Patients should be treated as early as possible, regardless of the severity of the initial symptoms. Considering an increasing number of reported cases with pembrolizumab induced MG, clinicians need to be more aware of this phenomenon. Pembrolizumab induced MG treatment usually occurs within 8 weeks after administration. The primary treatment for pembrolizumab induced MG is steroids. Other treatments include intravenous immunoglobulin, plasmapheresis, and immunomodulators such as rituximab and cyclosporine [ABSTRACT FROM AUTHOR]

Herein, we designed chitosan–coated Fe3O4 nanocomposites for the control release of drugs by an alternating magnetic field (AMF). The chitosan-coated Fe3O4 nanoparticles (Fe3O4@CS) were prepared by a alkaline co-precipitation method, and then, the model drug toluidine blue (TB) was covalently grafted onto the surface of the nanocomposite by a two-step amide reaction with the thermosensitive molecule 4,4′-azobis (4-cyanovaleric acid) (ACVA) as the linker group. The prepared nanocomposites were superparamagnetic and showed high magnetization saturation (about 54.0 emu g−1). In vitro hydrothermal release studies showed that most parts of the TB would be effectively enclosed within the nanocarriers at lower ambient temperatures (23 or 37 °C) due to the molecular bonding of ACVA. The results of kinetic fitting of hydrothermal release data showed that TB released from nanoparticles followed first-order kinetics (R2 > 0.99) and the Korsemeyer–Peppas model (R2 > 0.99, n < 0.5). Most importantly, a single magnetron release experiment demonstrated an approximately linear relationship between the cumulative release of the drug and the duration of action of AMF (R2 = 0.9712). Moreover, the increase in the cumulative release of the drug can be controlled by controlling the switch of the AMF generation device. Therefore, the ACVA-modified Fe3O4@CS nanocarrier designed in this study is a promising model for drug delivery that enables the control of drug release dose by AMF. [ABSTRACT FROM AUTHOR]

What is known and objective: Knowledge regarding the association between photosensitivity and pirfenidone is based mainly on case reports. The purpose of this article was to evaluate the clinical characteristics of photosensitivity associated with pirfenidone. Methods: We collected studies on photosensitivity induced by pirfenidone published from 2008 to 31 August 2021 in Chinese and English for a retrospective analysis. Results and discussion: The median age was 70 years (range 57–80) in 22 patients with pirfenidone‐induced photosensitivity. The dose at the onset of symptoms ranged from 600 to 2403 mg for the treatment of idiopathic pulmonary fibrosis. Pirfenidone‐induced photosensitivity occurred within 1 week in some patients and up to 8 months in others. The most common clinical manifestation of photosensitivity caused by pirfenidone was itching on body parts exposed to sunlight (back of hands, face, neck, and limbs) in 15 patients followed by erythema in 13 patients. Histopathological examination revealed necrotic keratinocytes, lymphocytic inflammatory cell infiltrate, hyperkeratosis and liquefaction degeneration in 5 patients. The photosensitivity test showed a markedly decreased minimum erythema dose (MED) of 7–228 mJ/cm2 UV‐B in 4 patients and 4.86–12 J/cm2 UV‐A in 5 patients. The clinical symptoms were significantly improved or completely relieved with a median time of 4 weeks (range 1–8) after drug withdrawal, dose reduction or systemic and topical glucocorticoid therapy. What is new and conclusion: Clinicians should be aware of the potential phototoxic effects of pirfenidone and should inform patients to take pirfenidone during (or after) a meal, avoid sun exposure, wear protective clothing, and apply broad‐spectrum sunscreen with high ultraviolet UVA and UVB protection. [ABSTRACT FROM AUTHOR]