Left Medial Lobe Research Articles

A method to map the visual cortex during an awake craniotomy

Much has been reported regarding the technique of performing an awake craniotomy with cortical mapping for the functional cortex responsible for sensorimotor activity and language. However, documentation for mapping the visual cortex during an awake craniotomy with a description of its technical details is rare. The authors report the case of a patient who underwent an awake craniotomy with mapping of the visual cortex to remove a glioma situated in the left medial occipital lobe. The techniques that made such a mapping procedure possible are discussed.

Magnetic resonance spectroscopy in the prediction of early conversion from amnestic mild cognitive impairment to dementia: a prospective cohort study

BackgroundMild cognitive impairment (MCI) of an amnestic type is a common condition in older people and highly predictive of Alzheimer's disease (AD). To date, there is no clear consensus regarding...

A patient with prosopagnosia which developed after an infarction in the left occipital lobe in addition to an old infarction in the right occipital lobe

A 66-year-old, right-handed male, was admitted to our hospital with difficulty in recognizing faces and colors. He had suffered a stroke in the right occipital region three years earlier that had induced left homonymous hemianopsia, but not prosopagnosia. A neurological examination revealed prosopagnosia, color agnosia, constructional apraxia, and topographical disorientation, but not either hemineglect or dressing apraxia. The patient was unable to distinguish faces of familiar persons such as his family and friends, as well as those of unfamiliar persons such as doctors and nurses. Brain MRI demonstrated an old infarction in the right medial occipital lobe and a new hemorrhagic infarction in the left medial occipital lobe, including the fusiform and lingual gyrus. It is unclear whether a purely right medial occipital lesion can be responsible for prosopagnosia, or whether bilateral medial occipital lesions are necessary for this occurrence. The current case indicated that bilateral medial occipital lesions play an important role in inducing porsopagnosia.

A Comparison of a Cyanaocrylate Glue (Glubran) vs. Fibrin Sealant (Tisseel) in Experimental Models of Partial Pulmonary Resection and Lung Incison in Rabbits

ABSTRACTIntroduction: Bronchopleural fistulas (BPF) and air leaks (AL) present major complications after pulmonary resection. Various tissue sealants have been proposed for their prevention, e.g., fibrin sealant (FS) and cyanoacrylate glues (CA). Contrary to the safety record of FS, substantial side effects such as foreign body reaction and impaired tissue integration have been reported for CA. This study compares the sealing efficacy and biocompatibility as well as side effects of FS and CA in experimental partial pulmonary resection and lung incision in rabbits. Methods: 26 New Zealand white rabbits (3 kg) were randomized to one of the three groups: partial pulmonary resection (A, acute model; n == 7 FS/ 7CA), lung incision [[2 (B; n == 3 FS/ 3 CA)]], and 14-day observation period (C; n == 3 FS/ 3 CA). In all groups (A, B, and C), FS was considered as control and CA as treatment. Surgery was carried out in general anaesthesia and mechanical ventilation. For partial lung resection a median thoracotomy was performed and the apex of the left median lobe was resected and the parenchymal surface covered with 0.09 ml of FS and CA. The thoraic cavity was filled with ringer solution after 5 minutes. The inspiratory minute volume (IMV) was increased by 0.02 l after every 4th inspiration. In groups B and C, a left lateral thoracotomy was performed in the 4th intercostal space and the left median lobe was incisised with a scalpel. The incison was covered with 0.5 ml of FS or CA. At autopsy (B and C) the operation site was assessed macroscopically. Histology was performed in all animals. Results: In terms of sealing purposes, FS and CA yielded comparable results in all groups. CA elicited a substantial increase of tissue temperature in the acute phase immediately after application (A). After 14 days CA residues were found, whereas FS was completely degraded. Histology showed a pronounced inflammatory response to CA but not to FS. We conclude that although the effect of airtight sealing was equally satisfying, our results emphasize that FS is preferable to CA for the prevention of BPF and AL due to superior biocompatibility and degradability. Longterm effects of CA residues on pulmonary tissue require further experimental testing.

Regional Distribution of Cytochrome P450 mRNA Expression in the Liver and Small Intestine of Cynomolgus Monkeys

The cynomolgus monkey is used to study drug metabolism because of its evolutionary closeness to humans. Despite their importance, regional distribution of cytochrome P450 (CYP) enzymes including CYP3As in the liver and small intestine, the major sites of drug metabolism, has not been fully investigated in cynomolgus monkeys. In this study, we measured mRNA expression levels of 14 CYPs in the CYP1, 2, and 3 subfamilies, including orthologs of human CYP3A4 and CYP3A5, in the liver and small intestine of cynomolgus monkeys. Expression levels of each CYP mRNA in various regions of the liver were quantified and comparisons were made between the right lobe, quadrate lobe, left medial lobe, left lateral lobe, and caudate lobe and with four different sections of the right lobe. In the small intestine, the same mRNAs were measured in the duodenum and six different sections from the proximal jejunum to the distal ileum. Expression levels of the CYP mRNAs were not substantially different between liver samples, but varied between the different sections of the small intestine, including CYP3A4. These results suggest that analysis of distinct sections is required for a better understanding of cynomolgus monkey CYPs in the small intestine.

Liver lobe torsion in a Shih‐tzu dog

MADAM We write to report a case of liver lobe torsion (LLT) in a small breed dog where ultrasound and computed tomography (CT) were useful in diagnosis of the condition. A 3-year-old male shih-tzu was presented with abdominal pain and acute onset vomiting, followed by progressive weakness. On examination the abdomen was tense and a firm painful mass was palpated cranially. Haematology and biochemistry profiles showed elevated liver enzymes, mild anaemia, and mild thrombocytosis. Abdominal radiographs showed a triangular mass in the cranial abdomen to the left of midline and caudal to the liver displacing the small intestine and the left kidney caudally. An abdominal ultrasound revealed a small volume of anechoic peritoneal effusion and an enlarged, homogenous, and hypoechoic left liver lobe. No blood flow was seen in the vessels including the hepatic veins and the portal veins within this liver lobe. Four detector-row CT was performed without anaesthesia. Pre-contrast CT revealed enlargement and caudoventral deviation of the left liver lobe with an irregular surface. Hypodense free fluid was present in the peritoneum. Post-contrast images showed no change in density of the abdominal left liver but normal contrast enhancement was seen in the remainder of the hepatic parenchyma (Figs 1A and 1B). A dorsal-plane image showed fissures on the liver surface, supporting rupture of the liver (Fig 1C, arrows). A diagnosis of LLT was made based on the imaging findings. Pre-contrast (A) and post-contrast (B,C) CT images through the cranial abdomen reveal an enlargement of the left lateral (LL) and left medial (LM) liver lobe without contrast enhancement. On dorsal-plane image, there are fissures on the liver surface (arrows) After a transfusion of whole blood, an exploratory laparotomy was performed. At surgery, 180 degree torsion of the left medial and left lateral liver lobe was identified and haemorrhagic peritoneal effusion and parenchymal rupture were present. A lobectomy of the affected regions was performed. The patient awoke from the anaesthesia, but died six hours after surgery. The cause of death was suspected to be severe postoperative complications. Most previous reports of LLT in dogs occurred in large breeds (Swann and Brown 2001, Schwartz and others 2006) and a few medium-sized breeds including the beagle (Sonnenfield and others 2001). To the author’s knowledge, this is the first case reported in such a small breed dog. Furthermore, this is the first report of the use of CT in diagnosis of the condition. Multiplanar reconstructions are particularly useful in assessment of complex anatomical abnormalities such as lung lobe torsion, and in this case, LLT. Liver lobe torsion, though very rare, should be considered in the differential diagnosis for acute abdominal pain, even in small breed dogs.

Utility of diffusion-weighted magnetic resonance imaging for liver fibrosis in chronic active hepatitis

We evaluated the utility of quantitative diffusion-weighted magnetic resonance imaging (DW-MRI) for assessing both the relationship between the degree of fibrosis and the histological activity index (HAI) in chronic hepatitis (CH) cases and attempted to determine whether the apparent diffusion coefficient value (ADC) could be used as a reference for the degree of fibrosis detected by histology. The study population consisted of 55 CH patients (Group I) and a control group of 30 volunteers (Group II). Group I consisted of 31 CH-B (CHB), 18 CH-C (CHC) and 6 non-alcoholic steatohepatitis patients. DW-MRI of the liver with b values of 0, 500 and 1000 s/mm(2) was performed, and liver biopsies of the patients were obtained two weeks later. The ADC value, degree of liver fibrosis and HAI were compared within Group I, and the ADC values of both groups were compared with each other. The ADC was lower in Group I than in Group II (P < 0.05). The ADC of the left lobe lateral (LL) (P < 0.05), left lobe medial (LM) and right lobe anterior (RA) segments (P < 0.01) in Group I were lower than those of Group II. There was no relationship between HAI and the ADC of LL, LM, RA and right lobe posterior (RP) segments in Group I. Additionally, there was no correlation between fibrosis scores and ADC in Group I, whereas there was a negative correlation between fibrosis scores and ADC values of the LL (28.3%) and RP (29.5%). CH patients had lower ADC values. There was no correlation between ADC values and fibrosis stages or ADC and HAI values. Quantitative DW-MRI was not useful in determining the degree of fibrosis in liver tissue.

Considerations for Implantation Site of VX2 Carcinoma into Rabbit Liver

To assess whether the implantation site of VX2 carcinoma into rabbit liver affects successful vessel selection for transcatheter arterial interventions. Twenty-four New Zealand White rabbits were randomly assigned to two groups. All implantations were performed by open laparotomy with minced tumor cells inserted into a 16-gauge Angiocath needle. Group I rabbits (n = 12) had tumor implanted into the left medial lobe of the liver and group II rabbits (n = 12) had tumor implanted into the left lateral lobe. Two weeks after implantation, selective angiography was performed for subsequent chemoembolization, which was part of a different study. Tested variables included maximum tumor diameter, tumor feeding artery size, and tumor vascularity. Successful tumor growth was achieved in all rabbits. Selective angiography was possible in 33.3% of rabbits in group I and 66.6% of rabbits in group II (P < .05). Tumor size and vascularity were similar between groups. Mean lengths of tumor feeder arteries from the bifurcation of the left hepatic artery were 4.1 mm +/- 1.2 in group I (left medial lobe) and 10.8 mm +/- 3.0 in group II (left lateral lobe; P < .05). The angulation of the left medial lobar artery (group I) off the left hepatic artery was acute in eight of 12 rabbits (66.6%), but only four of 12 rabbits in group II (33.3%) showed acute angulation of the left lateral lobar artery off the left hepatic artery (P < .05). Mean angiography time was significantly shorter in group II. For selective hepatic arterial interventions, the left lateral lobe of the liver may be favorable as an implantation site for VX2 tumors in rabbits.

Gross Anatomical Studies on the Portal Vein, Hepatic Artery and Bile Duct in the Liver of the Pig

Nowadays, pig has been chosen as the potential source of organs and cells for human to overcome a sever shortage of human material for clinical transplantation especially in the last 10 years by use of genetically modified swine. Consequently, the present study was conducted to give detailed information about the distribution of the blood vessels and bile ducts and their topographic relations, which may give a useful base for the hepatic segmentation in this animal aiming to provide a correct base for surgical procedures and liver transplantation. � The present study was conducted on 33 livers of pigs. Dissection, casting and radio-opaque techniques have been applied to show the different ramifications of the portal vein, hepatic artery and bile duct systems as well as their topographic relations with proposals of hepatic segmentation. The results revealed that, the caudate, right lateral and right medial lobes were supplied by R. dorsalis dexter and R. ventralis dexter of the portal vein in addition to R. dexter of the hepatic artery and right hepatic duct. The quadrate, left medial and left lateral lobes were supplied by the R. sinister of the portal vein and hepatic artery and left hepatic duct. � The liver of the pig could be divided into two independent segments; right and left. These two segments were separated by a segmental plane passed from the esophageal notch dorsally to the fossa of the gall bladder ventrally.

Adhesive Strength of Fibrinogen-Coated Collagen Patch or Liquid Fibrin Sealant in an Experimental Liver Resection Model in Pigs

Aim: The aim of this study was to assess the efficacy of sealing bile ducts by determining the adhesive strength of 2 different sealing agents, i.e. a fibrinogen-coated collagen patch (TachoSil®) and a liquid fibrin sealant (Tissucol®), in an experimental partial liver resection model in pigs. Methods: Pigs underwent laparotomy and partial resection of the left medial liver lobe. A 16-Ch silicon catheter was introduced into the common bile duct. Pigs were randomly assigned to 2 groups (n = 4 each). In group 1, TachoSil was applied on the resection surface, and in group 2 Tissucol was applied. After 2 h, pressure in the intrabiliary system was gradually increased. Results: No significant differences in the hemostasis times between TachoSil and Tissucol were observed (210.0 ± 12.9 vs. 208.8 ± 14.2 s; p = 0.9506). The pressure that could be resisted with Tissucol was significantly lower compared to TachoSil (77.0 ± 8.6 vs. 131.8 ± 16.3 mm Hg; p = 0.0405). Conclusions: The application of TachoSil on the resection surface is equally effective in obtaining hemostasis and in sealing of biliary ducts as Tissucol. The adhesive strength of TachoSil on the resection surface, however, is superior to Tissucol.

A Review of Porcine Foregut Anatomy for the Beginning Endoscopic Researcher

Purpose: Recently, there has been a rise in endolumenal and natural orifice translumenal endoscopic surgery (NOTES) research, most of which utilizes a porcine model. The size and function of the swine GI tract make it suitable for studying techniques with human equipment, but there are key anatomic differences. This abstract reviews porcine foregut anatomy for the beginning endoscopic researcher, highlighting relevant differences from human anatomy. Methods: We reviewed laboratory NOTES recordings to identify procedural difficulties related to porcine anatomy. Results: Esophagus: A 3–4 cm pharyngeal diverticulum is encountered in the caudal pharynx. The endoscope must be directed ventrally into the esophagus to avoid perforating the pharynx. Gastro-esophageal Junction (GEJ): The GEJ is located within the caudal mediastinum. Entry into this space during transesophageal procedures may lead to hemodynamic instability from vena cava compression. In addition, esophageal mucosa extends past the mechanical GEJ into the stomach; in contrast to the human, where the transition to gastric mucosa occurs in the esophagus. Stomach: The left extremity of the swine stomach is a conical blind pouch. Feed may be retained here, leading to potential contamination of the surgical site. Additionally, the stomach has greater mobility when insufflated than the human stomach, in part because of thinner omentum and loose attachments to surrounding organs. This mobility allows gastric rotation, which affects the reproducibility of gastrotomy creation. Furthermore, the stomach is U-shaped, making passage into the duodenum challenging. Pylorus: The torus pyloricus, a protuberance of muscle and fat, projects from the lesser curve near the pylorus, reducing the luminal size. This also complicates entry into the duodenum. Liver: The liver is large, multi-lobular and extremely convex on the diaphragmatic surface. The gall bladder is found in a fossa mainly on the right medial lobe but also partly on the left medial lobe. This location, and deep interlobular fissures, can make it challenging to access the gall bladder. The cystic duct and artery are smaller, less defined and longer in length than in humans. This increases the difficulty of identification and manipulation. Spleen: The spleen is large and mobile, characteristics which increase the chance of iatrogenic injury. Conclusion: The size of porcine foregut organs make them amenable to endoscopic research, but novice researchers must be cognizant of anatomical differences from humans when performing interventions.

Dextran Polymer Hemostatic Dressing Improves Survival in Liver Injury Model

Improvements in early hemorrhage control could result in more favorable outcomes. Several advanced hemostatic dressings are available; however, none meets the ideal characteristics defined by the United States Army. We studied the effects of a new dextran polymer hemostatic dressing on survival, blood loss, and blood pressure in a swine model of severe liver injury. We randomized 12 Yorkshire swine to treatment with either standard laparotomy pads or laparotomy pads coated with a dextran polymer (Bloxx). These dressings are visually identical, and investigators were not informed of the dressing assignment. We transected the left medial lobe of the liver in the anesthetized swine with a large knife, applied dressings immediately, and held pressure for 7 min. The animals received a weight-based maintenance crystalloid infusion without further resuscitation. Endpoints were blood loss, blood pressure, early mortality (120 min), and tissue histology. Baseline and pre-injury characteristics were similar between all animals. Three of six animals in the control group survived for 2 h while all six animals treated with Bloxx survived (P=0.05). Similarly, animals in the Bloxx group experienced less blood loss (10.4+/-8.8 mL/kg versus 28.3+/-13.0 mL/kg, P=0.025) and higher post-injury blood pressure than the control group. Bloxx was not associated with macroscopic or microscopic tissue damage. Bloxx is superior to standard laparotomy sponges in this model of lethal liver injury. Further study of this dressing is warranted to determine its potential for use in civilian and military trauma.

IC-P3-207: Decreased activation in the left medial parietal lobe in presymptomatic FAD mutation carriers in fMRI during an unrelated word pair memory task

2 and Lesion Explorer 3 WMH segmentation was performed, with VichowRobin perivascular spaces excluded. To appreciate the 3-dimensional anatomy of WMH, PV-WMH was defined as any hyperintensity touching the ventricles in 3D, the remaining discrete WMSH were defined as DWWMH. Hypointense components within PV-WMH and DW-WMH of cerebrospinal fluid intensity on T1-based segmentation were considered to represent cystic necrosis. Volumetrics were obtained. Hypointense lesion volumes were expressed as percentage of WMH. Results: Mean percentage of hypointensities were as follows: periventricular (AD 2.2%, NC 0.37%); deep white (AD 2.16%, NC 1.6%), with the PV between group difference approaching significance (p .07). Total PV-WMH and DW-WMH volumes was significantly correlated in NC (r .62, p .019) but not in AD (r .32, p .24). However, DW and PV hypointensities did not show correlation (NC: r -.05, p .87; AD: r .24, p .39). Conclusions: The higher percentage of implied cystic necrosis in the PV distribution, and the differences in DW and PV correlations in AD and NC, suggests a different underlying pathology occurring in the periventricular regions of AD patients. It is recommended that future studies examining WMH should include PV and DW delineations as well as an additional T1-based hypointense segmentation to account for these lesions.

P1-282: Decreased activation in the left medial parietal lobe in presymptomatic familial Alzheimer's disease mutation carriers in FMRI during an unrelated word pair memory task

P1-282: Decreased activation in the left medial parietal lobe in presymptomatic familial Alzheimer's disease mutation carriers in FMRI during an unrelated word pair memory task

EXPERIMENTAL MODELS OF HEPATECTOMY AND LIVER REGENERATION USING NEWBORN AND WEANING RATS

Liver regeneration is a complex process that has not been completely elucidated. The model most frequently used to study this phenomenon is 70% hepatectomy in adult rats; however, no papers have examined this effect in developing animals. The aims of the present study were: 1) to standardize two models of partial hepatectomy and liver regeneration in newborn suckling and weaning rats, and 2) to study the evolution of remnant liver weight and histological changes of hepatic parenchyma on the days that follow partial hepatectomy. Fifty newborn and forty-four weaning rats underwent 70% hepatectomy. After a midline incision, compression on both sides of the upper abdomen was performed to exteriorize the right medial, left medial and left lateral hepatic lobes, which were tied inferiorly and resected en bloc. The animals were sacrificed on days 0 (just after hepatectomy), 1, 2, 3, 4 and 7 after the operation. Body and liver weight were determined, and hepatic parenchyma was submitted to histological analysis. Mortality rates of the newborn and weaning groups were 30% and 0%, respectively. There was a significant decrease in liver mass soon after partial hepatectomy, which completely recovered on the seventh day in both groups. Newborn rat regenerating liver showed marked steatosis on the second day. In the weaning rat liver, mitotic figures were observed earlier, and their amount was greater than in the newborn. Suckling and weaning rat models of partial hepatectomy are feasible and can be used for studies of liver regeneration. Although similar, the process of hepatic regeneration in developing animals is different from adults.

Change of cerebral metabolism rate of glucose of cerebral white matter in Alzheimer's disease: a study with statistical parametric mapping software

To study the change of cerebral metabolism rate of glucose (CMRglc) of cerebral white matter in Alzheimer's Disease. Positron emission tomography (PET) was performed on 13 AD patients, 6 with behavioral and psychological symptoms of dementia (BPSD) and 7 without BPSD, and 10 healthy controls. The regional cerebral metabolism of glucose (rCMRglc) of some brain regions and nuclei were detected. (1) The rCMRglc of the cerebral white matter decreased extensively in the AD patients, especially in the right frontal lobe, superior gyrus of the left frontal lobe (P = 0.001). (2) The rCMRglc of subcortical white matter of the left medial prefrontal lobe and the left cuneus of occipital lobe increased in the AD patients. (3) The levels of rCMRglc of the subcortical white matter of both side middle occipital lobe, left cuneus of occipital lobe, right inferior parietal lobule, left fusiform gyrus of temporal lobe and the left medial prefrontal lobe were all significantly higher in the AD patients with BPSD than in those without BPSD (P = 0.001). While the levels of rCMRglc of the subcortical white matter of both side paracentral lobule, right superior and middle frontal lobe, and left superior temporal lobe were all significantly lower in the AD patients with BPSD than in those without BPSD (all P = 0.001). There is diffuse abnormal rCMRglc in the cerebral white matter in the AD patients: the rCMRglc decreases in the frontal-temporal-occipital association area, and the rCMRglc of the medial prefrontal lobe and cuneus of occipital lobe increases. BPSD is correlated with the abnormal metabolism of related cerebral regions.

Alterations in the Content of Metal Elements and Fatty Acids in Hepatic Ischaemia–Reperfusion: Induction of Apoptotic and Necrotic Cell Death

Ischaemia and reperfusion are related to oxidative stress, which alters with the redox-homeostasis of the liver cells. Our aim was to reveal the correlations between changes of metal element and fatty acid concentration (two main components of redox-balance) and apoptotic and necrotic processes of hepatic ischaemia-reperfusion. Wistar rats were divided into three groups: control, sham-operated and reperfusion. Hepatic ischaemia was induced for 45 min in the left lateral, left medial and right medial lobes followed by 24 h of reperfusion. Global redox parameters and glutathione peroxidase and superoxide dismutase activity were detected by luminometry and spectrophotometry. Routine laboratory measurements, fatty acid composition (with gas chromatography) as well as metal ion concentration of liver (with ICP-OES) were determined. Metallothionein activity was measured by atomic absorption spectrometry. Immunohistochemical and histological examinations were carried out to investigate apoptotic and necrotic changes in the liver. During reperfusion, global antioxidant parameters decreased and superoxide dismutase level of the liver was significantly lower than in the sham-operated group. Changes in the metal element concentration are essential for cellular biochemical pathways, and significant correlations were found between decrease in Cu and Zn content and decreased superoxide dismutase activity. Necrotic lesions along with increased number of apoptotic cells were found in the liver after 24 h of reperfusion. Alterations in the metal element and fatty acid content was found in the liver tissue during 24 h of ischaemia-reperfusion along with increase in the number of apoptotic cells and significant disturbance of the antioxidant balance. Study of the metal element content of the liver during hepatic ischaemia-reperfusion may provide new supportive strategies for liver surgery and transplantation.

Effect of MG132 on proteasome activity and prooxidant/antioxidant status of rat liver subjected to ischemia/reperfusion injury

Previous studies have shown that proteasome inhibitors exerted protective effects against ischemia/reperfusion injury (IRI) of brain, heart, kidney and intestine. The aim of the present study was to investigate: (i) whether the proteasome inhibitor MG132 protects rat liver against IRI; and (ii) whether MG132 modulates prooxidant/antioxidant status of rat liver subjected to warm IRI. The left lateral and medial lobes (approximately 70% of the total liver volume) of livers of male Wistar rats were subjected to 30-min ischemia followed by 60-min reperfusion. Lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels were measured in the plasma. Proteasome chymotryptic-like (ChT-L) activity, levels of thiobarbituric acid-reactive substances (TBARS), protein carbonyls (PC) and glutathione (GSH), as well as superoxidase dismutase (SOD), catalase (CAT), glutathionine peroxidase and glutathionine reductase activities were measured in liver fractions. Thirty-min ischemia followed by 60-min reperfusion increased liver TBARS and PC, CAT and SOD activities, but decreased GSH level. Ischemia/reperfusion-induced oxidative stress was exacerbated in mitochondria, indicating that these organelles are the preferential target of IRI. Plasma LDH and AST levels were decreased by MG132 during both ischemia and reperfusion, while ALT values were decreased only after 30 min of reperfusion. MG132 did not significantly affect liver TBARS and GSH levels, but it increased PC and decreased ChT-L activity; the activities of CAT and SOD were also decreased. MG132 exerts a protective effect during the early phase of reperfusion and it modulates prooxidant/antioxidant status of rat liver subjected to warm IRI.

Intrahepatic ramifications of the portal vein in the horse

Summary The ramifications of the portal vein in the liver of horses were studied by using corrosion casting and gross dissection. The portal vein in the horse supplies the hepatic lobes by six major branches. The right lobe is supplied by three main branches, namely the dorsal diaphragmatic, the right caudodorsal and the right intermediate branches. The left branch supplies the left lateral and medial lobes and parts of the quadrate lobe adjacent to the left medial lobe. The caudate branch supplies caudate process of the caudate lobe. The right common trunk supplies also a part of right lobe and quadrate lobe. Therefore, the pattern of blood distribution in portal vein of horse differs from that of other species.

Deficit of social cognition in subjects with surgically treated frontal lobe lesions and in subjects affected by schizophrenia.

The ability of humans to predict and explain other people’s behaviour by attributing independent mental states such as desires and beliefs to them, is considered to be due to our ability to construct a “Theory of Mind”. Recently, several neuroimaging studies have implicated the medial frontal lobes as playing a critical role in a dedicated “mentalizing” or “Theory of Mind” network in the human brain. In this study we compare the performance of patients with right and left medial prefrontal lobe lesions in theory of mind and in social cognition tasks, with the performance of people with schizophrenia.We report a similar social cognitive profile between patients with prefrontal lobe lesions and schizophrenic subjects in terms of understanding of false beliefs, in understanding social situations and in using tactical strategies. These findings are relevant for the functional anatomy of “Theory of Mind”.