Encapsulated liquid crystals as probes for remote thermometry.

A temperature probe based on the magnetic resonance properties of an encapsulated liquid crystal has been investigated. Large changes in magnetic resonance signals occur as the liquid crystal undergoes a phase transition from an anisotropic (nematic) state to the isotropic liquid. The low latent heat of such phase transitions allows for rapid phase changes during a hyperthermia treatment. Transition temperatures can be tailored by adding suitable compounds such as analogues of the liquid crystal or various solvents. Encapsulation is required to maintain the integrity of the liquid crystal, particularly for applications in vivo. Results of preliminary studies designed to demonstrate the technical feasibility of the concept are presented.     

The endoscopic spectrum of primary non-Hodgkin's lymphoma of the stomach

Thirty-one consecutive patients with primary non-Hodgkin's lymphoma of the stomach were studied to outline the spectrum of endoscopic abnormalities. The 17 men and 14 women had a median age of 65 years. There were 22 patients in stage I and 9 in stage II. Three endoscopic patterns were recognized: diffuse infiltration (9), ulceration (9) and polypoid lesions (13). There was no apparent correlation between the endoscopic appearance and the grading or subtype of the malignancy. Local recurrence did not occur once complete remission was obtained. The disease-free 5-year survival rate was 45%. Recognition of these endoscopic patterns may lead to earlier detection and, hopefully, improved survival.     

Na/P(i) cotransporter ( Npt2) gene disruption increases duodenal calcium absorption and expression of epithelial calcium channels 1 and 2

Mice homozygous for the disrupted type-II Na/P(i) cotransporter gene ( Npt2(-/-)) exhibit hypophosphataemia, increased serum concentration of 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) and calcium (Ca) and elevated urinary Ca excretion. To determine whether the hypercalcaemia and hypercalciuria are secondary to 1,25-(OH)(2)D-stimulated intestinal Ca absorption, we examined the effect of Npt2 gene disruption on serum Ca and urinary Ca excretion after an overnight fast, and on duodenal Ca absorption. We also compared the duodenal expression of the epithelial Ca channels, ECaC1 and ECaC2, and calbindinD(9K) mRNAs, relative to that of beta-actin mRNA, in Npt2(+/+) and Npt2(-/-) mice. Both serum Ca and urine Ca/creatinine were significantly decreased in Npt2(-/-) mice after an overnight fast and were no longer different from that in wild-type mice. Absorption of (45)Ca from isolated duodenal segments in vivo and (45)Ca appearing in the plasma were significantly increased in Npt2(-/-) compared with Npt2(+/+) mice. In addition, the duodenal abundance of ECaC1, ECaC2 and calbindinD(9K) mRNAs was significantly elevated in mutant mice relative to that in wild-type mice. In contrast, both duodenal Ca absorption and ECaC1 and ECaC2 mRNA abundance were lower in mice with X-linked hypophosphataemia ( Hyp) than in normal littermates. In summary, we provide evidence for increased duodenal Ca absorption in Npt2(-/-) mice and suggest a role for ECaC1, ECaC2 and calbindinD(9K) in mediating this response.     

The lipoprotein profile of women with hyperprolactinaemic amenorrhoea

The aim of this study was to evaluate the lipoprotein profile in women with hyperprolactinaemic amenorrhoea and to establish whether effective dopamine agonist therapy might have a beneficial effect. Blood samples were collected from women with hyperprolactinaemic amenorrhoea and from controls matched for age, body mass index and smoking. Follow-up blood samples were collected from women on dopamine agonist therapy as treatment for their hyperprolactinaemia. Plasma cholesterol, high density lipoprotein cholesterol, low density lipoprotein (LDL) cholesterol, very low density lipoprotein cholesterol, triglycerides, serum oestradiol and prolactin were measured. No statistically significant differences were found in the lipoprotein profile of the patient (n = 15) and control (n = 15) groups. During treatment with the dopamine agonist, bromocriptine (n = 9), significant reduction in total cholesterol [4.87 (3.98-5.87) versus 5.60 (4.55-6.61) mmol/l, P = 0.024] and LDL cholesterol [3.22 (2.01-4.23) versus 3.72 (2.59-4.93) mmol/l, P = 0.033] was noted. We conclude that beneficial alterations in the lipoprotein profile may occur in response to effective dopamine agonist therapy, presumably as a consequence of return of ovarian function and alleviation of oestrogen deficiency. Women with hyperprolactinaemic amenorrhoea should be encouraged to take effective therapy to improve their lipoprotein profile and potentially reduce their cardiovascular risk.     

The response of human leucocyte cultures to stimulation by tuberculin and phytohaemagglutinin measured by the uptake of radioactive thymidine

A method is described for assessing the lymphocyte transformation of human leucocyte cultures induced by phytohaemagglutinin (PHA) and tuberculin purified protein derivative (PPD) by the measurement of the uptake of [¹⁴C]thymidine. The thymidine uptake of the cultures has been expressed as percentage of the total activity added. The mean basal uptake of twenty-two unstimulated cultures was 0·96%. The mean uptake of twenty-four PHA stimulated cultures was 19·5%, whilst the mean uptake of eleven PPD stimulated cultures from seven subjects, who were strongly positive on skin testing to tuberculin, was 20·1%. A rise of thymidine uptake was detected in five out of six tuberculin negative subjects (mean uptake 3·8%). Hydrocortisone hemisuccinate in final concentrations of 5 and 50 μg/ml usually reduced the thymidine uptake of unstimulated and PHA and PPD stimulated cultures, though the total cell count was reduced in only four out of ten cultures. An increase of thymidine from 1 to 64 μg/culture resulted in twoto three-fold increase in the uptake of thymidine; further increase of thymidine added to the cultures to 256 μg/culture resulted in a decrease of thymidine uptake.     

Full-left-full-right split liver transplantation for adult recipients: a systematic review and meta-analysis

Full-left-full-right split liver transplantation (FSLT) for adult recipients, may increase the availability of liver grafts, reduce waitlist time, and benefit recipients with below-average body weight. However, FSLT may lead to impaired graft and patient survival. This study aims to assess outcomes after FSLT. Five databases were searched to identify studies concerning FSLT. Incidences of complications, graft- and patient survival were assessed. Discrete data were pooled with random-effect models. Graft and patient survival after FSLT were compared with whole liver transplantation (WLT) according to the inverse variance method. Vascular complications were reported in 25/273 patients after FSLT (Pooled proportion: 6.9%, 95%CI: 3.1–10.7%, I²: 36%). Biliary complications were reported in 84/308 patients after FSLT (Pooled proportion: 25.6%, 95%CI: 19–32%, I²: 44%). Pooled proportions of graft and patient survival after 3 years follow-up were 72.8% (95%CI: 67.2–78.5, n = 231) and 77.3% (95%CI: 66.7–85.8, n = 331), respectively. Compared with WLT, FSLT was associated with increased graft loss (pooled HR: 2.12, 95%CI: 1.24–3.61, P = 0.006, n = 189) and patient mortality (pooled HR: 1.81, 95%CI: 1.17–2.81, P = 0.008, n = 289). FSLT was associated with high incidences of vascular and biliary complications. Nevertheless, long-term patient and graft survival appear acceptable and justify transplant benefit in selected patients.     

Health-related quality of life,uncertainty and coping strategies in solid organ transplant recipients during shielding for the COVID-19 pandemic

Strict isolation of vulnerable individuals has been a strategy implemented by authorities to protect people from COVID-19. Our objective was to investigate health-related quality of life (HRQoL), uncertainty and coping behaviours in solid organ transplant (SOT) recipients during the COVID-19 pandemic. A cross-sectional survey of adult SOT recipients undergoing follow-up at our institution was performed. Perceived health status, uncertainty and coping strategies were assessed using the EQ-5D-5L, Short-form Mishel Uncertainty in Illness Scale (SF-MUIS) and Brief Cope, respectively. Interactions with COVID-19 risk perception, access to health care, demographic and clinical variables were assessed. The survey was completed by 826 of 3839 (21.5%) invited participants. Overall, low levels of uncertainty in illness were reported, and acceptance was the major coping strategy (92%). Coping by acceptance, feeling protected, self-perceived susceptibility to COVID-19 were associated with lower levels of uncertainty. Health status index scores were significantly lower for those with mental health illness, compromised access to health care, a perceived high risk of severe COVID-19 infection and higher levels of uncertainty. A history of mental health illness, risk perceptions, restricted healthcare access, uncertainty and coping strategies was associated with poorer HRQoL in SOT recipients during strict isolation. These findings may allow identification of strategies to improve HRQoL in SOT recipients during the pandemic.     

Conservering van cosmetica en contactlensvloeistoffen

Conclusie De verscheidenheid aan conserveermiddelen die in cosmetica worden toegepast, is zeer groot. Het is wenselijk het gebruik van deze verbindingen zo beperkt mogelijk te houden in verband met ongewenste bijwerkingen voor de gebruikers. Een effectieve conservering van produkten, waarin micro-organismen goed kunnen groeien, is echter noodzakelijk. Deskundige microbiologische begeleiding bij de ontwikkeling en fabricage van cosmetische produkten is dan ook essentieel.

---

---

Voordracht gehouden tijdens het symposium Conserveermiddelen op 13 november 1980 te Rotterdam.

---

Dit artikel wordt gelijktijdig geplaatst in De Waren Chemicus.