Warming and Salt Intrusion Affect Microcystin Production in Tropical Bloom-Forming Microcystis

The Vietnamese Mekong Delta is predicted to be one of the regions most impacted by climate change, causing increased temperature and salinity in inland waters. We hypothesized that the increase in temperature and salinity may impact the microcystin (MC) production of two Microcystis strains isolated in this region from a freshwater pond (strain MBC) and a brackish water pond (strain MTV). The Microcystis strains were grown at low (27 °C), medium (31 °C), high (35 °C) and extremely high (37 °C) temperature in flat photobioreactors (Algaemist). At each temperature, when cultures reached a stable state, sea salt was added to increase salinity to 4‰, 8‰, 12‰ and 16‰. MC concentrations and cell quota were reduced at high and extremely high temperatures. Salinity, in general, had comparable effects on MC concentrations and quota. At a salinity of 4‰ and 8‰, concentrations of MC per mL of culture and MC cell quota (based on chlorophyll, dry-weight and particle counts) were higher than at 0.5‰, while at the highest salinities (12‰ and 16‰) these were strongly reduced. Strain MBC produced five MC variants of which MC-RR and MC-LR were most abundant, followed by MC-YR and relatively low amounts of demethylated variants dmMC-RR and dmMC-LR. In strain MTV, MC-RR was most abundant, with traces of MC-YR and dmMC-RR only in cultures grown at 16‰ salinity. Overall, higher temperature led to lower MC concentrations and cell quota, low salinity seemed to promote MC production and high salinity reduced MC production. Hence, increased temperature and higher salinity could lead to less toxic Microcystis, but since these conditions might favour Microcystis over other competitors, the overall biomass gain could offset a lower toxicity.     

Cerebral microbleeds in CADASIL

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary arteriopathy leading to recurrent cerebral infarcts and dementia. Intracerebral hemorrhage (ICH) has been described sporadically in patients with CADASIL, suggesting that the affected arteries in CADASIL are not bleed-prone. However, the presence of cerebral microbleeds, which often remain undetected on conventional MRI, has not been determined in CADASIL. OBJECTIVE: To determine whether cerebral vessels in patients with CADASIL are prone to microbleeding. METHODS: T2*-weighted gradient echo MRI, which is highly sensitive for visualizing microbleeds, was performed in patients with CADASIL and their family members (n = 63). Known risk factors for ICH were determined for all individuals. On an exploratory basis, the presence of cerebral microbleeds was correlated with demographic variables, vascular risk factors, disease progression, ischemic MR lesions, and genotype. RESULTS: Cerebral microbleeds were present in 31% of symptomatic CADASIL mutation carriers, predominantly in the thalamus. Vascular risk factors such as hypertension did not account for the microbleeds in these patients. Factors associated with microbleeds were age (p = 0.008), Rankin disability score (p = 0.017), antiplatelet use (p = 0.025), number of lacunae on MRI (p = 0.009), and the Arg153Cys Notch3 mutation (p = 0.017). After correction for age, only the Arg153Cys mutation remained significantly associated with the presence of microbleeds. CONCLUSION: Patients with CADASIL have an age-related increased risk of intracerebral microbleeds. This implies that they may have an increased risk for ICH, which should be taken into account in CADASIL diagnosis and patient management.     

Prepidil compared to Propess for cervical ripening

OBJECTIVES: To compare the efficacy and safety of intracervical PGE(2) gel (Prepidil) with intravaginal PGE(2) insert (Propess) in cervical ripening and induction of labour. STUDY DESIGN: This was a retrospective analysis of patients with single pregnancies, intact membranes and a viable fetus who required cervical ripening. In the first half of 1998, all patients received Prepidil and in the first half of 1999 all patients received Propess. In both periods 50 consecutive files were retrieved and compared. RESULTS: The Prepidil and Propess group were similar in patient characteristics, indication for induction of labour and delivery outcome. Cervical ripening within 24 h was achieved in the Propess group in 80% as compared to 56% in the Prepidil group. The application-membrane rupture-interval was shorter in the Propess group compared to the Prepidil group (23.7 +/- 21.3 h versus 56.4 +/- 77.7 h, P = 0.009) as well as the application-delivery interval (29.8 +/- 22.0 h versus 62.0 +/- 78.8 h, P = 0.039). In the Propess group 62% delivered within 24 h compared to 28% in the Prepidil group. A smaller number of applications was observed in the Propess group (1.2 versus 1.8, P < 0.005). Both methods proved to be safe in cervical priming and no relevant differences in mode of delivery and outcome of labour were detected. None of the patients required an emergency caesarean section during the treatment with prostaglandines. CONCLUSIONS: Both prostaglandin E(2) agents are safe and effective in achieving cervical ripening; however the vaginal insert demonstrated a shorter application-delivery interval. The hospital stay was consequently shorter, contributing to cost effectiveness.     

Shifting Incidence of Solitary Adenomas in the Era of Minimally Invasive Parathyroidectomy. A Multi-Institutional Study

Background

Previously, when a conventional neck exploration (CNE) without preceding diagnostic imaging was the surgical treatment for patients with primary hyperparathyroidism (pHPT) solitary adenomas were observed in 69–88% of patients. The advent of minimally invasive parathyroidectomy (MIP), aiming at a preoperatively identified parathyroid abnormality may be associated with a different incidence of solitary and multiglandular parathyroid disease.

Materials and Methods

In a cohort of 467 patients with sporadic pHPT who preferentially underwent MIP in four hospitals in the same geographical region, the incidence of solitary adenomas, multiple adenomas, and multiglandular hyperplasia (MGD) was evaluated.

Results

A total of 367 patients were scheduled for MIP; 100 patients underwent a planned CNE. The overall surgical success rate of the first operation was 93%, and the cumulative success rate, including a second operative procedure, was 99%. Normocalcemia resulted from removing 1 abnormal PG in 426 patients (91%) and more than one abnormal gland in 35 patients (8%). A parathyroid carcinoma was diagnosed in four of the 426 patients with a single abnormal gland. Four gland hyperplasia was observed in 1 patient. In hospitals where diagnostic workup usually consisted of ultrasound (US) and computed tomography (CT) the incidence of solitary adenomas was 88%, compared with 96% in hospitals where MIBI, US, and CT were used preoperatively (P = 0.007).

Conclusions

A higher frequency of solitary adenomas was observed than historically reported. The extent of the preoperative workup influences the number of observed solitary adenomas.     

A study of PROforma, a development methodology for clinical procedures.

Knowledge engineering has shown that besides the general methodologies from software engineering it is useful to develop special purpose methodologies for knowledge based systems (KBS). PROforma is a newly developed methodology for a specific type of knowledge based systems. PROforma is intended for decision support systems and in particular for clinical procedures in the medical domain. This paper reports on an evaluation study of PROforma, and on the trade-off that is involved between general purpose and special purpose development methods in Knowledge Engineering and Medical AI. Our method for evaluating PROforma is based on re-engineering a realistic system in two methodologies: the new and special purpose KBS methodology PROforma and the widely accepted, and more general KBS methodology CommonKADS. The four most important results from our study are as follows. Firstly, PROforma has some strong points which are also strong related to requirements of medical reasoning. Secondly, PROforma has some weak points, but none of them are in any way related to the special purpose nature of PROforma. Thirdly, a more general method like CommonKADS works better in the analysis phase than the more special purpose method PROforma. Finally, to support a complementary use of the methodologies, we propose a mapping between their respective languages.     

Redundancy in the International Anorectal Physiology Working Group Manometry Protocol: A Diagnostic Accuracy Study in Fecal Incontinence

Digestive Diseases and Sciences - Anorectal manometry (ARM) is essential for identifying sphincteric dysfunction. The International Anorectal Physiology Working Group (IAPWG) protocol and London...