Higher‐level language deficits resulting from left primary cerebellar lesions

Background: Contemporary neuropsychological studies suggest that cerebellar lesions may impact upon higher‐level cognitive functioning via mechanisms of crossed cerebello‐cerebral diaschisis. Accordingly, right cerebellar lesions have been previously associated with linguistic impairments such as reduced word fluency and agrammatic output. Recently, however, neuroimaging investigations have also identified ipsilateral cerebral hypoperfusion as a consequence of cerebellar lesions, implicating a potential role for the left cerebellum in the mediation of language processes. Aims: The purpose of this research was to investigate the effects of left cerebellar lesions of vascular origin, on general as well as high‐level language skills. Methods & Procedures: Linguistic profiles were compiled for five individuals with left primary cerebellar lesions utilising a comprehensive language test battery. Individual scores relevant to each subtest were compared to a group of non‐neurologically impaired controls. The criterion for anomalous performance was established as ≥ 1.5 SD below the mean of the control group. Outcomes & Results: The findings of this research suggest that higher‐level language deficits may result from left primary cerebellar lesions. All participants demonstrated deficits on measures of word fluency, sentence construction within a set context, producing word definitions, and producing multiple definitions for the same word. Deficits were also noted for several participants on measures of understanding figurative language, forming word associations, identifying and correcting semantic absurdities, and producing synonyms and antonyms. Conclusions: The results presented challenge the notion of a lateralised linguistic cerebellum, supporting a potential role for the left as well as right cerebellar hemispheres in the regulation of language processes, presumably via cerebellar‐basal ganglia/thalamo‐cortical pathways.     

Capturing fleeting intermediates in a catalytic C–H amination reaction cycle

We have applied an ambient ionization technique, desorption electrospray ionization MS, to identify transient reactive species of an archetypal C–H amination reaction catalyzed by a dirhodium tetracarboxylate complex. Using this analytical method, we have detected previously proposed short-lived reaction intermediates, including two nitrenoid complexes that differ in oxidation state. Our findings suggest that an Rh-nitrene oxidant can react with hydrocarbon substrates through a hydrogen atom abstraction pathway and raise the intriguing possibility that two catalytic C–H amination pathways may be operative in a typical bulk solution reaction. As highlighted by these results, desorption electrospray ionization MS should have broad applicability for the mechanistic study of catalytic processes.     

Powdered infant formula as a source of Salmonella infection in infants.

Powdered infant formula is not sterile and may be intrinsically contaminated with pathogens, such as Salmonella enterica, that can cause serious illness in infants. In recent years, at least 6 outbreaks of Salmonella infection in infants that have been linked to the consumption of powdered infant formula have been reported. Many of these outbreaks were identified because the Salmonella strains were unique in some way (e.g., a rare serotype) and a well-established Salmonella surveillance network, supported by laboratories capable of serotyping isolates, was in place. Another common feature of the outbreaks was the low level of salmonellae detected in the implicated formula (salmonellae may be missed in routine testing). These outbreaks likely represent only a small proportion of the actual number of Salmonella infections in infants that have been linked to powdered infant formula. Managing this problem requires a multidimensional approach in which manufacturers, regulators, and caregivers to infants can all play a role.     

Pulmonary Langerhans cell histiocytosis: emerging concepts in pathobiology,radiology, and clinical evolution of disease

Pulmonary Langerhans cell histiocytosis (PLCH) is an uncommon disorder of adult smokers associated with a significant morbidity. Arising from the aberrant accumulation of Langerhans and other immune cells, PLCH tends to cause a relatively isolated pulmonary involvement as compared to other forms of Langerhans cell (LC) and histiocytic disorders. Increased knowledge of cytokine triggers, dendritic cell trafficking, and clonality of LC populations in PLCH have resulted in an improved understanding of the pathobiology of PLCH. High-resolution CT (HRCT) of the chest has led to better appreciation of nodular and cystic radiographic abnormalities characteristic of the disease. Correlation of HRCT abnormalities with lung pathologic changes has led to an improved comprehension of clinical evolution of PLCH. Current clinical predictors for PLCH outcomes remain poor, although long-term follow-up and radiologic monitoring may help to define disease progression. This review discusses advances in PLCH emphasizing the etiopathologic bases of the disease and currently available radiologic modalities for monitoring disease progression.     

Effectiveness of diclofenac versus paracetamol in knee osteoarthritis: a randomised controlled trial in primary care

Background

The effectiveness of diclofenac versus paracetamol in primary care patients with pain caused by knee osteoarthritis is unclear.

Aim

To assess the effectiveness of diclofenac compared with paracetamol over a period of 2, 4, and 12 weeks in patients with knee osteoarthritis.

Design and setting

Randomised controlled trial in general practice.

Method

There were 104 patients included in the study, they were aged ≥45 years consulting their GP with knee pain caused by knee osteoarthritis. Patients were randomly allocated to diclofenac (n = 52) or paracetamol (n = 52) for at least 2 weeks. Primary outcomes were daily knee pain severity, and knee pain and function measured with the Knee Injury and Osteoarthritis Outcome Score (KOOS).

Results

Over a period of 2- and 4-weeks follow-up, no significant difference in daily knee pain was found between the patient groups: estimated differences of 0.5 (95% CI = −0.2 to 1.3) and −0.2 (95% CI = −1.0 to 0.7), respectively. Over the 12-weeks follow-up, no significant differences were found between both groups for KOOS pain: estimated difference of −2.8 (95% CI = −10.7 to 5.1) and KOOS function of −2.7 (−10.6 to 5.0).

Conclusion

Over a period of 2- and 4-weeks follow-up no significant difference in daily measured knee pain severity was found between primary care patients with knee osteoarthritis taking paracetamol or diclofenac. Also, over a period of 12-weeks follow-up no significant differences were found regarding KOOS pain and KOOS function between both groups. Patients more frequently reported minor adverse events after taking diclofenac (64%) than paracetamol (46%).     

Differential effects of nitric oxide on erythroid and myeloid colony growth from CD34+ human bone marrow cells

Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL- 60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S- nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit- granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo.     

Influence of Delays on Perforation Risk in Adults with Acute Appendicitis

Purpose  This study analyzed whether prehospital or in-hospital delay was the more significant influence on perforation rates for acute appendicitis and whether any clinical feature designated patients requiring higher surgical priority. Methods  A retrospective analysis was conducted over one year at a tertiary referral hospital without a dedicated emergency surgical theater. Admission notes, theater logbook, and the Hospital Inpatient Enquiry system were reviewed to identify the characteristics and clinical course of patients aged greater than 16 years who were operated upon for histologically confirmed acute appendicitis. Results  One hundred and fifteen patients were studied. The overall perforation rate was 17 percent. The mean duration of symptoms prior to hospital presentation was 38.1 hours with the mean in-hospital waiting time prior to operation being 23.4 hours. Although body temperature on presentation was significantly greater in patients found to have perforated appendicitis (P < 0.05), only patient heart rate at presentation and overall duration of symptoms, but not in-hospital waiting time, independently predicted perforation by stepwise linear regression modeling. Conclusion  In-hospital delay was not an independent predictor of perforation in adults with acute appendicitis although delays may contribute if patients are left to wait unduly. Tachycardia at presentation may be a quantifiable feature of those more likely to have perforation and who should be given higher surgical priority.