Use of the 90Sr applicator for intraoperative radiation therapy in a mouse tumor model

Intraoperative radiation therapy (IORT) research is limited by the lack of small-animal models. We have implanted B16 melanoma into mouse kidneys, which we subsequently operated upon and irradiated with beta rays from a ⁹⁰Sr ophthalmic applicator. The IORT has effectively prolonged survival and produced some cures. The strategy should be applicable to other murine tumors and to other internal implantation sites.     

Immunogenicity of guinea pig cells transformed in culture by chemical carcinogens

The immunogenicity of inbred strain 2/N guinea pig fibroblasts transformed to the malignant state in vitro by chemical carcinogens was evaluated with the use of a variety of in vivo and in vitro methods including delayed-type hypersensitivity skin and tumor transplantation tests and analysis of antibody production by immunofluorescence, complement fixation, and staphylococcal protein A binding tests. Neoplastic transformation was induced by direct treatment of cells in culture with benzo[a]pyrene, 3-methylcholanthrene, or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or by the host-mediated method by which fetuses were exposed to diethylnitrosamine or MNNG in vivo prior to cell culture. Rabbits and syngeneic guinea pigs were inoculated with unirradiated and X-irradiated clonally derived cells. Delayed hypersensitivity skin reactions to immunizing or other cells were equivalent in immunized or control guinea pigs, and no protection to tumor outgrowth from a challenge inoculum of immunizing cells was observed. Antibody activity induced in the sera of immunized guinea pigs was cross-reactive and removed by absorption with nontumorigenic cells. Rabbit antisera after absorption with fetal guinea pig cells were nonreactive with the specific immunizing or other culture cells. Chemical carcinogen-induced neoplastic transformation of guinea pig cells can, therefore, occur without formation of detectable, individually distinct cell surface tumor-specific neoantigens.     

Planificación y manejo anestésico para cesárea en gestante con neumonía por SARS-CoV-2

Pregnant women experience physiological and immunological changes which make them more prone to all kind of viral and bacterial infections, this is because they have been considered as vulnerable group if infected by SARS-CoV-2. They could even deploy a severe form of this disease which may require to end pregnancy to improve oxygenation and to safeguard foetal wellbeing the in case the mother situation gets worse. In this scenario, any intervention would require a detailed planning by the whole surgical team, and, specifically, by the anaesthesiologists, in order to guarantee both mother and child wellbeing and to prevent from infections all the healthcare team. We describe the case of 37 week pregnant woman, admitted in our Critical Care Unit with respiratory high flows device support, due to severe respiratory failure due to COVID-19 which needed an urgent caesarean section.     

Restoring Perivascular Adipose Tissue Function in Obesity Using Exercise

Purpose

Perivascular adipose tissue (PVAT) exerts an anti-contractile effect which is vital in regulating vascular tone. This effect is mediated via sympathetic nervous stimulation of PVAT by a mechanism which involves noradrenaline uptake through organic cation transporter 3 (OCT3) and β₃-adrenoceptor-mediated adiponectin release. In obesity, autonomic dysfunction occurs, which may result in a loss of PVAT function and subsequent vascular disease. Accordingly, we have investigated abnormalities in obese PVAT, and the potential for exercise in restoring function.

Methods

Vascular contractility to electrical field stimulation (EFS) was assessed ex vivo in the presence of pharmacological tools in ±PVAT vessels from obese and exercised obese mice. Immunohistochemistry was used to detect changes in expression of β₃-adrenoceptors, OCT3 and tumour necrosis factor-α (TNFα) in PVAT.

Results

High fat feeding induced hypertension, hyperglycaemia, and hyperinsulinaemia, which was reversed using exercise, independent of weight loss. Obesity induced a loss of the PVAT anti-contractile effect, which could not be restored via β₃-adrenoceptor activation. Moreover, adiponectin no longer exerts vasodilation. Additionally, exercise reversed PVAT dysfunction in obesity by reducing inflammation of PVAT and increasing β₃-adrenoceptor and OCT3 expression, which were downregulated in obesity. Furthermore, the vasodilator effects of adiponectin were restored.

Conclusion

Loss of neutrally mediated PVAT anti-contractile function in obesity will contribute to the development of hypertension and type II diabetes. Exercise training will restore function and treat the vascular complications of obesity.

     

Chikungunya and dengue fever among hospitalized febrile patients in northern Tanzania

Consecutive febrile admissions were enrolled at two hospitals in Moshi, Tanzania. Confirmed acute Chikungunya virus (CHIKV), Dengue virus (DENV), and flavivirus infection were defined as a positive polymerase chain reaction (PCR) result. Presumptive acute DENV infection was defined as a positive anti-DENV immunoglobulin M (IgM) enzyme-linked immunsorbent assay (ELISA) result, and prior flavivirus exposure was defined as a positive anti-DENV IgG ELISA result. Among 870 participants, PCR testing was performed on 700 (80.5%). Of these, 55 (7.9%) had confirmed acute CHIKV infection, whereas no participants had confirmed acute DENV or flavivirus infection. Anti-DENV IgM serologic testing was performed for 747 (85.9%) participants, and of these 71 (9.5%) had presumptive acute DENV infection. Anti-DENV IgG serologic testing was performed for 751 (86.3%) participants, and of these 80 (10.7%) had prior flavivirus exposure. CHIKV infection was more common among infants and children than adults and adolescents (odds ratio [OR] 1.9, P = 0.026) and among HIV-infected patients with severe immunosuppression (OR 10.5, P = 0.007). CHIKV infection is an important but unrecognized cause of febrile illness in northern Tanzania. DENV or other closely related flaviviruses are likely also circulating.     

Brucellosis among Hospitalized Febrile Patients in Northern Tanzania

Acute and convalescent serum samples were collected from febrile inpatients identified at two hospitals in Moshi, Tanzania. Confirmed brucellosis was defined as a positive blood culture or a ≥ 4-fold increase in microagglutination test titer, and probable brucellosis was defined as a single reciprocal titer ≥ 160. Among 870 participants enrolled in the study, 455 (52.3%) had paired sera available. Of these, 16 (3.5%) met criteria for confirmed brucellosis. Of 830 participants with ≥ 1 serum sample, 4 (0.5%) met criteria for probable brucellosis. Brucellosis was associated with increased median age (P = 0.024), leukopenia (odds ratio [OR] 7.8, P = 0.005), thrombocytopenia (OR 3.9, P = 0.018), and evidence of other zoonoses (OR 3.2, P = 0.026). Brucellosis was never diagnosed clinically, and although all participants with brucellosis received antibacterials or antimalarials in the hospital, no participant received standard brucellosis treatment. Brucellosis is an underdiagnosed and untreated cause of febrile disease among hospitalized adult and pediatric patients in northern Tanzania.