Left Ventricular Morphology of the Giraffe Heart Examined by Stereological Methods

The giraffe heart has a relative mass similar to other mammals, but generates twice the blood pressure to overcome the gravitational challenge of perfusing the cerebral circulation. To provide insight as to how the giraffe left ventricle (LV) is structurally adapted to tackle such a high afterload, we performed a quantitative structural study of the LV myocardium in young and adult giraffe hearts. Tissue samples were collected from young and adult giraffe LV. Design‐based stereology was used to obtain unbiased estimates of numbers and sizes of cardiomyocytes, nuclei and capillaries. The numerical density of myocyte nuclei was 120 × 10³ mm^?3 in the adult and 504 × 10³ mm^?3 in the young LV. The total number (N) of myocyte nuclei was 1.3 × 10¹¹ in the adult LV and 4.9 × 10¹⁰ in the young LV. In the adult LV the volume per myocyte was 39.5 × 10³ µm³ and the number of nuclei per myocyte was 4.2. The numerical density of myocytes was 24.1 × 10⁶ cm^?3 and the capillary volume fraction of the adult giraffe ventricle was 0.054. The significantly higher total number of myocyte nuclei in the adult LV, the high density of myocyte nuclei in the LV, and the number of nuclei per myocyte (which was unusually high compared to other mammalian, including human data), all suggest the presence of myocyte proliferation during growth of the animal to increase wall thickness and normalize LV wall tension as the neck lengthens and the need for higher blood pressure ensues. Anat Rec, 296:611–621, 2013. © 2013 Wiley Periodicals, Inc.     

Interaction between blood type,smoking and factor V Leiden mutation and risk of venous thromboembolism: a Danish case‐cohort study

See also Lowe GDO. Epidemiology of venous thromboembolism: the need for large (including prospective) studies and meta‐analyses. This issue, pp 2186–8 and Rosendaal FR. Etiology of venous thrombosis: the need for small original studies. This issue, pp 2189–90.     

Percutaneous nephrolithotripsy under assisted local anaesthesia for high risk patients: Is it effective?

ObjectivesThe aim of the present study is to evaluate the feasibility and safety of performing PNL under local anesthesia in a selected group of patients who are at high risk for general anesthesia.Patients and methodsForty seven patients underwent PNL under local anesthesia. There were 38 males and 9 females with a mean age of 62 years. All patients were at medical high-risk for general anesthesia, with an American Society of Anesthesiologists (ASA) score of 3. The indications for local anesthesia in this study were obstructed single functioning kidney with azotemia in 29 patients, hepatic insufficiency in 8 patients, cardiac problems in 7 patients and 3 patients had hepatocellular carcinoma. The mean stone size was 2.7 cm (range 2–3.1 cm). Local infiltration with 10–20 cc of 2% lidocaine at the site of puncture was used in all cases. Narcotics were given 30 min prior to the procedure and medazolam was given intraoperatively upon demand. Utrasound guided puncture was performed in all cases and tract dilatation was then done under fluoroscopy using high pressure balloon catheter in 35 and Alken's metal dilators in 12 cases. Stones were then retrieved after disintegration in the same cession in 33 patients, while the other 14 patients underwent staged PNL, where a 12 Fr. nephrostomy tube was placed in the first stage, followed by tract dilatation and stone retrieval one week later.ResultsOut of 47 patients included, 44 had successful PNL either one stage (30 patients) or two stages (14 patients). Only 3 patients could not tolerate pain and the procedure was terminated after placement of nephrostomy tube and stone retrieval was completed later under general anesthesia.ConclusionOur results demonstrated that PNL under local anesthesia with narcotics and sedatives seems to be a satisfying solution for the treatment of a selected group of patients with renal pelvic stones and who have high anesthetic risk. However, additional studies with different groups of patients are required to validate our results.     

Parental reflective functioning and executive functioning in mothers with substance use disorder

Having a substance use disorder (SUD) may adversely affect caregiving capacities. Reflective functioning (RF) and executive functioning (EF) are both important capacities for sensitive parenting, and are often impaired in a SUD. Only a few studies have explored the possible association between the two phenomena. In this study, we used a neuropsychological test battery to assess EF, and the Parent Development Interview to assess RF in a sample of mothers with a SUD (N = 43). Although parental RF (PRF) was associated with EF, when controlled for intelligence (IQ) and mental health, there was no significant association between EF and PRF. Mental health, however, showed a significant negative association with PRF. Splitting the group in two based on PRF level, mothers with a negative to low PRF exhibited more severe difficulties in SUD-related aspects, as well as in several EF components, compared to mothers with an adequate to high PRF, highlighting the association between EF and PRF. The results from this study contribute to enhance our understanding of the dynamics underlying vulnerability in PRF that mothers with small children may experience. We suggest EF to be a prerequisite for adequate PRF, and for interventions to be customized accordingly regarding parents with a SUD.