Effects of pericardiectomy on training- and myocardial infarction-induced left ventricular hypertrophy, chamber dimensions and gene expression.

The primary purpose of the study was to evaluate whether a pericardiectomy (PERI) alters training- or myocardial infarction (MI)-induced left ventricular hypertrophy (LVH), chamber geometry, gene expression and/or running performance. Mice were randomized into 6 groups: naïve control (CONT)-sedentary (Sed), CONT-trained (Tr), PERI-Sed, PERI-Tr, MI-Sed and MI-Tr. MI mice also received a pericardiectomy as part of the MI surgical procedure. 10 weeks of treadmill running resulted in enhanced running performance-to-exhaustion in all 3 trained groups (CONT-Tr, PERI-Tr, MI-Tr) compared to sedentary cohorts (P<0.001). Training also resulted in similar increases in normalized LVH (LV/BW) in CONT-Tr and PERI-Tr mice. 2D-echocardiographic evaluation of LV internal chamber dimensions revealed that stroke diameter (SD) was larger in PERI compared to MI (P<0.01) but not CONT mice. Ventricular B-type natriuretic peptide mRNA (BNP) was elevated only in the 2 MI groups. Left ventricle ß1-adrenergic receptor (ß1-AR) and melusin transcripts both demonstrated an overall increase in trained compared to sedentary mice (both P<0.05). Additionally long-term pericardiectomy did not further enhance running performance or increase LV/BW in either sedentary or trained mice.

Association between novel MRI-estimated pancreatic fat and liver histology-determined steatosis and fibrosis in non-alcoholic fatty liver disease.

BACKGROUND: Ectopic fat deposition in the pancreas and its association with hepatic steatosis have not previously been examined in patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD). AIM: To quantify pancreatic fat using a novel magnetic resonance imaging (MRI) technique and determine whether it is associated with hepatic steatosis and/or fibrosis in patients with NAFLD. METHODS: This is a cross-sectional study including 43 adult patients with biopsy-proven NAFLD who underwent clinical evaluation, biochemical testing and MRI. The liver biopsy assessment was performed using the NASH-CRN histological scoring system, and liver and pancreas fat quantification was performed using a novel, validated MRI biomarker; the proton density fat fraction. RESULTS: The average MRI-determined pancreatic fat in patients with NAFLD was 8.5% and did not vary significantly between head, body, and tail of the pancreas. MRI-determined pancreatic fat content increased significantly with increasing histology-determined hepatic steatosis grade; 4.6% in grade 1; 7.7% in grade 2; 13.0% in grade 3 (P = 0.004) respectively. Pancreatic fat content was lower in patients with histology-determined liver fibrosis than in those without fibrosis (11.2% in stage 0 fibrosis vs. 5.8% in stage 1-2 fibrosis, and 6.9% in stage 3-4 fibrosis, P = 0.013). Pancreatic fat did not correlate with age, body mass index or diabetes status. CONCLUSIONS: In patients with NAFLD, increased pancreatic fat is associated with hepatic steatosis. However, liver fibrosis is inversely associated with pancreatic fat content. Further studies are needed to determine underlying mechanisms to understand if pancreatic steatosis affects progression of NAFLD.

Correlation between liver histology and novel magnetic resonance imaging in adult patients with non-alcoholic fatty liver disease - MRI accurately quantifies hepatic steatosis in NAFLD.

BACKGROUND: Conventional magnetic resonance imaging (MRI) techniques that measure hepatic steatosis are limited by T1 bias, T(2)* decay and multi-frequency signal-interference effects of protons in fat. Newer MR techniques such as the proton density-fat fraction (PDFF) that correct for these factors have not been specifically compared to liver biopsy in adult patients with non-alcoholic fatty liver disease (NAFLD). AIM: To examine the association between MRI-determined PDFF and histology-determined steatosis grade, and their association with fibrosis. METHODS: A total of 51 adult patients with biopsy-confirmed NAFLD underwent metabolic-biochemical profiling, MRI-determined PDFF measurement of hepatic steatosis and liver biopsy assessment according to NASH-CRN histological scoring system. RESULTS: The average MRI-determined PDFF increased significantly with increasing histology-determined steatosis grade: 8.9% at grade-1, 16.3% at grade-2, and 25.0% at grade-3 with P ≤ 0.0001 (correlation: r(2) = 0.56, P < 0.0001). Patients with stage-4 fibrosis, when compared with patients with stage 0-3 fibrosis, had significantly lower hepatic steatosis by both MRI-determined PDFF (7.6% vs. 17.8%, P < 0.005) and histology-determined steatosis grade (1.4 vs. 2.2, P < 0.05). NAFLD patients with grade 1 steatosis were more likely to have characteristics of advanced liver disease including higher average AST:ALT (0.87 vs. 0.60, P < 0.02), GGT (140 vs. 67, P < 0.01), and INR (1.06 vs. 0.99, P < 0.01), higher stage of fibrosis and hepatocellular ballooning. CONCLUSIONS: MRI-determined proton density-fat fraction correlates with histology-determined steatosis grade in adults with NAFLD. Steatosis is non-linearly related to fibrosis progression. In patients with NAFLD, a low amount of hepatic steatosis on imaging does not necessarily indicate mild disease.

Number of portal tract macrophages correlates with the modified hepatic activity index in chronic hepatitis C infection.

The Ishak modified hepatic activity index (mHAI) is widely used to score disease activity in chronic hepatitis C infection. However, the scoring of the mHAI components is subjective and prone to interobserver variation. Liver injury results in increased numbers of portal tract macrophages, which are easily identified via periodic acid-Schiff with diastase digestion stain. Evaluation of 30 liver biopsies from patients with chronic hepatitis C revealed increasing numbers of portal tract macrophages as scores of liver inflammation increased. Specifically, the number of PASD-positive portal tract macrophages per centimeter of biopsy length correlated with the level of portal inflammation and total mHAI score, and these correlations were statistically significant (P = .039 and .029, respectively). Although the portal macrophage count appeared to correlate with the interface activity and lobular necroinflammatory score, this did not meet statistical significance (P = .073 and .079, respectively). Interobserver agreement by κ analysis was greater for the portal macrophage count than for any individual component of the mHAI score. In summary, the number of periportal ceroid-laden macrophages correlates with liver inflammation as measured using the mHAI, with better interobserver agreement. This technique may serve as a useful adjunct to the mHAI in the assessment of liver injury in hepatitis C.

Causes of death or reasons for euthanasia in military working dogs: 927 cases (1993-1996).

OBJECTIVE: To determine causes of death or reasons for euthanasia in a population of military working dogs. DESIGN: Retrospective study. ANIMALS: 927 military working dogs. PROCEDURE: Records of all military working dogs that died during the period from 1993 to 1996 were evaluated for cause of death or reason for euthanasia by review of necropsy and histopathology reports, death certificates, and daily clinical treatment sheets. A single primary cause of death or euthanasia was determined. RESULTS: Although sexually intact male dogs were more numerous in the study population, castrated male dogs typically lived longer than spayed females or sexually intact males. Leading causes of death or euthanasia (76.3% of all dogs) were appendicular degenerative joint disease, neoplasia, spinal cord disease, nonspecific geriatric decline, and gastric dilatation-volvulus. Compared with German Shepherd Dogs, Belgian Shepherd Dogs were at increased risk for death attributable to neoplasia, behavior, and respiratory tract disease. German Shepherd Dogs had nearly twice the risk for death associated with spinal cord diseases, compared with Belgian Shepherd Dogs. CONCLUSIONS AND CLINICAL RELEVANCE: For most military working dogs, death or euthanasia results from a few diseases commonly associated with advanced age. Some breed differences in risk for these diseases may exist, which clinicians should consider in the procurement and long-term management of these dogs.

The class C Vps complex functions at multiple stages of the vacuolar transport pathway.

The Class C Vps complex, consisting of Vps11, Vps16, Vps18, and Vps33, is required for SNARE-mediated membrane fusion at the lysosome-like yeast vacuole. However, Class C vps mutants display more severe and pleiotropic phenotypes than mutants specifically defective in endosome-to-vacuole transport, suggesting that there are additional functions for the Class C Vps complex. A SNARE double mutant which is defective for both Golgi-to-endosome and endosome-to-vacuole trafficking replicates many of the phenotypes observed in Class C vps mutants. We show that genetic interactions exist between Class C vps alleles and alleles of the Class D vps group, which are defective in the docking and fusion of Golgi-derived vesicles at the endosome. Moreover, the Class D protein Vac1 was found to physically bind to the Class C Vps complex through a direct association with Vps11. Finally, using a random mutagenic screen, a temperature-conditional allele which shares many of the phenotypes of mutants which are selectively defective in Golgi-to-endosome trafficking was isolated (vps11-3ts). Collectively, these results indicate that the Class C Vps complex plays essential roles in the processes of membrane docking and fusion at both the Golgi-to-endosome and endosome-to-vacuole stages of transport.

Incidence of zoonotic diseases in military working dogs serving in Operations Desert Shield and Desert Storm.

The United States deployed 118 military working dogs (MWDs) to the Persian Gulf theater during Operations Desert Shield and Desert Storm. This study is a retrospective descriptive study of medical records of these deployed dogs, with the objective to determine whether there were infectious or parasitic diseases with a zoonotic potential in a sentinel population of MWDs that may be of concern to Persian Gulf veterans. Fifty-one percent of visits to veterinary treatment facilities during deployment were for illness or injury. Potential zoonotic conditions accounted for 21% of the total visits, 41% of the "sick-call" visits, and 63% of presentations for illness to veterinary treatment facilities. This study did not determine whether the diseases treated were transmitted between MWDs and the troops. Although the etiologic agents were not determined in these cases, no evidence was found supporting new or reemerging illnesses in this population of dogs.

Class C Vps protein complex regulates vacuolar SNARE pairing and is required for vesicle docking/fusion.

In yeast, the Class C Vps protein complex (C-Vps complex), composed of Vps11, Vps16, Vps18, and Vps33, functions in Golgi-to-vacuole protein transport. In this study, we characterized and purified this complex and identified its interaction with the syntaxin homolog Vam3. Vam3 pairs with the SNAP-25 homolog Vam7 and VAMP homolog Vti1 to form SNARE complexes during vesicle docking/fusion with the vacuole. The C-Vps complex does not bind to Vam3-Vti1-Vam7 paired SNARE complexes but instead binds to unpaired Vam3. Antibodies to a component of this complex inhibited in vitro vacuole-to-vacuole fusion. Furthermore, temperature-conditional mutations in the Class C VPS genes destabilized Vam3-Vti1-Vam7 pairing. Therefore, we propose that the C-Vps complex associates with unpaired (activated) Vam3 to mediate the assembly of trans-SNARE complexes during both vesicle docking/fusion and vacuole-to-vacuole fusion.

The surgical pathology and cytopathology of US Persian Gulf War military veterans.

BACKGROUND: Tens of thousands of Persian Gulf War veterans (GWVs) have presented with medical symptoms since Operation Desert Shield and Operation Desert Storm. The Kuwait Registry at the Armed Forces Institute of Pathology was established to act as a repository for surgical pathology, cytopathology, and autopsy material from GWVs. OBJECTIVE: To identify conditions known to be endemic to the theater of operations in our cohort of GWVs. METHODS: The Kuwait Registry database was searched by computer for listed conditions endemic to the Persian Gulf region included in the registry through December 31, 1997. RESULTS: Of the 2582 patients in this cohort, 1 patient with hepatitis B and 15 patients with hepatitis C were identified. Other known endemic conditions of the Persian Gulf region were not found. CONCLUSIONS: Viral hepatitis (B and C), which is prevalent in the US population, was the only listed endemic condition identified in surgical pathology or cytopathology specimens in our cohort of GWVs.

The Department of Defense Medical Mortality Registry.

The Department of Defense Medical Mortality Registry is being implemented at the Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, providing the first comprehensive medical mortality surveillance for the Department of Defense. The Registry attempts to obtain complete medical and circumstantial information on every military active duty death for medical surveillance and prevention research. Medical records, autopsy reports, eyewitness accounts, and investigative reports are reviewed to validate and synthesize medical, circumstantial, and risk factor information on each death. All military active duty deaths since 1980 are currently identified and classified by manner of death (accident, suicide, homicide, illness, hostile, undetermined). Military death rates have decreased during the past two decades by nearly half. About three-quarters of military deaths are attributable to injury (accident, suicide, homicide). The Registry creates new opportunities for prevention-oriented research as it collects detailed information on every military death.

A comparison of cervical pathology between United States Air Force women who did and did not serve in the Persian Gulf War.

PURPOSE: The purpose of this study was to look objectively at cervical cytological differences between women Gulf War female veterans (GWFV) and Gulf War-era active duty females not deployed to the Gulf (NDF) during Operation Desert Shield/Desert Storm using Pap smear results. METHODS: A cohort of 6715 active duty Air Force women who also served on active duty between August 7, 1990-March 1, 1991 provided at least one Pap smear as part of routine medical care during 1994. Of these, 1446 were identified as GWFV and 5269 were identified as NDF. Diagnoses were compared using Chi-square tests with Yate's continuity correction. RESULTS: There were no differences between the two groups, overall, in the diagnosis of other than within normal limits (OTWNL), the diagnoses of significant disease or in Bethesda system diagnoses in each of the three years for which comparisons were made. GWFV diagnosed in the 26-30 age group were significantly more likely to have a diagnosis of OTWNL than were NDF in the same age group in 1994. There were no differences between the two groups in any other age category. CONCLUSIONS: The data provide little support for the hypothesis that a difference exists between GWFV and NDF with respect to abnormal cervical cytology.

Estrogen increases hyperemic microvascular blood flow velocity in postmenopausal women.

BACKGROUND: Epidemiologic studies suggest that estrogen replacement therapy (ERT) is protective against vascular disease. ERT confers this benefit by lowering lipid levels and improving arterial function. However, its effect on the microvasculature in vivo is unknown. Thus the purposes of this study were to evaluate effect of estrogen status on the hyperemic response of the microvasculature in vivo in postmenopausal women and to compare the hyperemic response of the microvasculature in postmenopausal women taking ERT with that of premenopausal women. METHODS: We measured forearm microvasculature flow velocity by using a laser Doppler in a cross section of 64 healthy premenopausal and postmenopausal women 23 to 72 years old. Microvasculature blood flow velocity was measured at baseline. throughout 2 minutes of ischemia, and immediately after the ischemic period was terminated (i.e., during the peak hyperemic response). RESULTS: The peak of the hyperemic flow velocity (PHFV) in the postmenopausal women who were taking long-term ERT at usual doses was greater than that of postmenopausal women who were not currently taking ERT (p < .0001). Moreover, the PHFV of postmenopausal women taking ERT was similar to that of premenopausal women. Multivariate regression analysis showed estrogen status and baseline flow velocity to be independent predictors of PHFV. CONCLUSIONS: Current, long-term ERT at usual replacement doses is associated with improved microvascular responses in postmenopausal women, which may explain some of its beneficial vascular effects.

The three-dimensional structure of a Plasmodium falciparum cyclophilin in complex with the potent anti-malarial cyclosporin A.

Cyclosporin A (CsA) is a potent anti-malarial compound in vitro and in vivo in mice though better known for its immunosuppressive properties in humans. Crystal structures of wild-type and a double mutant Plasmodium falciparum cyclophilin (PfCyP19 and mPfCyP19) complexed with CsA have been determined using diffraction terms to a resolution of 2.1 A (1 A=0.1 nm). The wild-type has a single PfCyP19/CsA complex per asymmetric unit in space group P1 and refined to an R-work of 0.15 and R-free of 0.19. An altered cyclophilin, with two accidental mutations, Phe120 to Leu in the CsA binding pocket and Leu171 to Trp at the C terminus, presents two complexes per asymmetric unit in the orthorhombic space group P2(1)2(1)2. This refined to an R-work of 0.18 and R-free 0.21. The mutations were identified from the crystallographic analysis and the C-terminal alteration helps to explain the different crystal forms obtained. PfCyP19 shares approximately 61 % sequence identity with human cyclophilin A (hCyPA) and the structures are similar, consisting of an eight-stranded antiparallel beta-barrel core capped by two alpha-helices. The fold creates a hydrophobic active-site, the floor of which is formed by side-chains of residues from four antiparallel beta-strands and the walls from loops and turns. We identified C-H.O hydrogen bonds between the drug and protein that may be an important feature of cyclophilins and suggest a general mode of interaction between hydrophobic molecules. Comparisons with cyclophilin-dipeptide complexes suggests that a specific C-H.O hydrogen bonding interaction may contribute to ligand binding. Residues Ser106, His99 and Asp130, located close to the active site and conserved in most cyclophilins, are arranged in a manner reminiscent of a serine protease catalytic triad. A Ser106Ala mutant was engineered to test the hypothesis that this triad contributes to CyP function. Mutant and wild-type enzymes were found to have similar catalytic properties.

A study of the lifetime occurrence of neoplasia and breed differences in a cohort of German Shepherd Dogs and Belgian Malinois military working dogs that died in 1992.

The population of U.S. Department of Defense military working dogs provides an opportunity to study the lifetime occurrence of neoplasia in 2 breeds of dogs--the German Shepherd Dog and the Belgian Malinois. Medical records were reviewed for all dogs that died or were euthanized in 1992 (135 German Shepherd Dogs and 106 Belgian Malinois). Histologically confirmed neoplasms were recorded. More than 30% of both breeds (41 German Shepherd Dogs and 33 Belgian Malinois) developed at least 1 primary neoplasm during their lives, with 10% developing more than 1 neoplasm. Nearly 57% of the neoplasms were benign, and approximately 43% were malignant. German Shepherd Dogs lived 9.7 years, on average, and Belgian Malinois lived 7.9 years, on average. Of the dogs that developed any neoplasm, Belgian Malinois had a mean age at 1st diagnosis that was 1.1 years younger and a mean age at 1st diagnosis of malignancy that was 1.7 years younger than those in German Shepherd Dogs. The risk of a malignancy being the cause of death or euthanasia of a Belgian Malinois was 4.21 times the risk in German Shepherd Dogs (95% CI: 1.32, 13.47). Seminoma was the malignancy that occurred most frequently. Hemangioma was the benign neoplasm that occurred most frequently. Veterinarians identified masses clinically at equal rates in both groups.

Abnormal neurotransmission in mice lacking synaptic vesicle protein 2A (SV2A).

Synaptic vesicle protein 2 (SV2) is a membrane glycoprotein common to all synaptic and endocrine vesicles. Unlike many proteins involved in synaptic exocytosis, SV2 has no homolog in yeast, indicating that it performs a function unique to secretion in higher eukaryotes. Although the structure and protein interactions of SV2 suggest multiple possible functions, its role in synaptic events remains unknown. To explore the function of SV2 in an in vivo context, we generated mice that do not express the primary SV2 isoform, SV2A, by using targeted gene disruption. Animals homozygous for the SV2A gene disruption appear normal at birth. However, they fail to grow, experience severe seizures, and die within 3 weeks, suggesting multiple neural and endocrine deficits. Electrophysiological studies of spontaneous inhibitory neurotransmission in the CA3 region of the hippocampus revealed that loss of SV2A leads to a reduction in action potential-dependent gamma-aminobutyric acid (GABA)ergic neurotransmission. In contrast, action potential-independent neurotransmission was normal. Analyses of synapse ultrastructure suggest that altered neurotransmission is not caused by changes in synapse density or morphology. These findings demonstrate that SV2A is an essential protein and implicate it in the control of exocytosis.

Regional anesthesia. Nerve blocks of the extremities and face.

Regional nerve blocks are useful for anesthetizing the hand and fingers, the foot and toes, and the face and mouth. These simple procedures may be performed prior to wound repair or surgery of the affected area. The authors discuss the indications, techniques, dosages, and potential complications of regional anesthesia.

Local anesthesia. Topical application, local infiltration, and field block.

Local anesthetics are warranted whenever a clinical procedure causes pain that could be eliminated by their use. Their effectiveness is influenced by many factors, particularly the choice of agent and the technique of administration. The authors discuss the clinical uses and advantages of common local anesthetics and describe three techniques used in the primary care setting: topical application, local infiltration, and field block.

Vac1p coordinates Rab and phosphatidylinositol 3-kinase signaling in Vps45p-dependent vesicle docking/fusion at the endosome.

The vacuolar protein sorting (VPS) pathway of Saccharomyces cerevisiae mediates transport of vacuolar protein precursors from the late Golgi to the lysosome-like vacuole. Sorting of some vacuolar proteins occurs via a prevacuolar endosomal compartment and mutations in a subset of VPS genes (the class D VPS genes) interfere with the Golgi-to-endosome transport step. Several of the encoded proteins, including Pep12p/Vps6p (an endosomal target (t) SNARE) and Vps45p (a Sec1p homologue), bind each other directly [1]. Another of these proteins, Vac1p/Pep7p/Vps19p, associates with Pep12p and binds phosphatidylinositol 3-phosphate (PI(3)P), the product of the Vps34 phosphatidylinositol 3-kinase (PI 3-kinase) [1] [2]. Here, we demonstrate that Vac1p genetically and physically interacts with the activated, GTP-bound form of Vps21p, a Rab GTPase that functions in Golgi-to-endosome transport, and with Vps45p. These results implicate Vac1p as an effector of Vps21p and as a novel Sec1p-family-binding protein. We suggest that Vac1p functions as a multivalent adaptor protein that ensures the high fidelity of vesicle docking and fusion by integrating both phosphoinositide (Vps34p) and GTPase (Vps21p) signals, which are essential for Pep12p- and Vps45p-dependent targeting of Golgi-derived vesicles to the prevacuolar endosome.