VMA21 deficiency causes an autophagic myopathy by compromising V-ATPase activity and lysosomal acidification.

X-linked myopathy with excessive autophagy (XMEA) is a childhood-onset disease characterized by progressive vacuolation and atrophy of skeletal muscle. We show that XMEA is caused by hypomorphic alleles of the VMA21 gene, that VMA21 is the diverged human ortholog of the yeast Vma21p protein, and that like Vma21p it is an essential assembly chaperone of the V-ATPase, the principal mammalian proton pump complex. Decreased VMA21 raises lysosomal pH, which reduces lysosomal degradative ability and blocks autophagy. This reduces cellular free amino acids, which upregulates the mTOR pathway and mTOR-dependent macroautophagy, resulting in proliferation of large and ineffective autolysosomes that engulf sections of cytoplasm, merge together, and vacuolate the cell. Our results uncover macroautophagic overcompensation leading to cell vacuolation and tissue atrophy as a mechanism of disease.

RyR1 deficiency in congenital myopathies disrupts excitation-contraction coupling.

In skeletal muscle, excitation-contraction (EC) coupling is the process whereby the voltage-gated dihydropyridine receptor (DHPR) located on the transverse tubules activates calcium release from the sarcoplasmic reticulum by activating ryanodine receptor (RyR1) Ca(2+) channels located on the terminal cisternae. This subcellular membrane specialization is necessary for proper intracellular signaling and any alterations in its architecture may lead to neuromuscular disorders. In this study, we present evidence that patients with recessive RYR1-related congenital myopathies due to primary RyR1 deficiency also exhibit downregulation of the alfa 1 subunit of the DHPR and show disruption of the spatial organization of the EC coupling machinery. We created a cellular RyR1 knockdown model using immortalized human myoblasts transfected with RyR1 siRNA and confirm that knocking down RyR1 concomitantly downregulates not only the DHPR but also the expression of other proteins involved in EC coupling. Unexpectedly, this was paralleled by the upregulation of inositol-1,4,5-triphosphate receptors; functionally however, upregulation of the latter Ca(2+) channels did not compensate for the lack of RyR1-mediated Ca(2+) release. These results indicate that in some patients, RyR1 deficiency concomitantly alters the expression pattern of several proteins involved in calcium homeostasis and that this may influence the manifestation of these diseases.

VMA21 deficiency prevents vacuolar ATPase assembly and causes autophagic vacuolar myopathy.

X-linked Myopathy with Excessive Autophagy (XMEA) is a childhood onset disease characterized by progressive vacuolation and atrophy of skeletal muscle. We show that XMEA is caused by hypomorphic alleles of the VMA21 gene, that VMA21 is the diverged human ortholog of the yeast Vma21p protein, and that like Vma21p, VMA21 is an essential assembly chaperone of the vacuolar ATPase (V-ATPase), the principal mammalian proton pump complex. Decreased VMA21 raises lysosomal pH which reduces lysosomal degradative ability and blocks autophagy. This reduces cellular free amino acids which leads to downregulation of the mTORC1 pathway, and consequent increased macroautophagy resulting in proliferation of large and ineffective autolysosomes that engulf sections of cytoplasm, merge, and vacuolate the cell. Our results uncover a novel mechanism of disease, namely macroautophagic overcompensation leading to cell vacuolation and tissue atrophy.

A previously unidentified MECP2 open reading frame defines a new protein isoform relevant to Rett syndrome.

Rett syndrome is caused by mutations in the gene MECP2 in approximately 80% of affected individuals. We describe a previously unknown MeCP2 isoform. Mutations unique to this isoform and the absence, until now, of identified mutations specific to the previously recognized protein indicate an important role for the newly discovered molecule in the pathogenesis of Rett syndrome.

Mutations in NHLRC1 cause progressive myoclonus epilepsy.

Lafora progressive myoclonus epilepsy is characterized by pathognomonic endoplasmic reticulum (ER)-associated polyglucosan accumulations. We previously discovered that mutations in EPM2A cause Lafora disease. Here, we identify a second gene associated with this disease, NHLRC1 (also called EPM2B), which encodes malin, a putative E3 ubiquitin ligase with a RING finger domain and six NHL motifs. Laforin and malin colocalize to the ER, suggesting they operate in a related pathway protecting against polyglucosan accumulation and epilepsy.

Clinical and genetic findings in a large cohort of patients with ryanodine receptor 1 gene-associated myopathies.

Ryanodine receptor 1 (RYR1) mutations are a common cause of congenital myopathies associated with both dominant and recessive inheritance. Histopathological findings frequently feature central cores or multi-minicores, more rarely, type 1 predominance/uniformity, fiber-type disproportion, increased internal nucleation, and fatty and connective tissue. We describe 71 families, 35 associated with dominant RYR1 mutations and 36 with recessive inheritance. Five of the dominant mutations and 35 of the 55 recessive mutations have not been previously reported. Dominant mutations, typically missense, were frequently located in recognized mutational hotspot regions, while recessive mutations were distributed throughout the entire coding sequence. Recessive mutations included nonsense and splice mutations expected to result in reduced RyR1 protein. There was wide clinical variability. As a group, dominant mutations were associated with milder phenotypes; patients with recessive inheritance had earlier onset, more weakness, and functional limitations. Extraocular and bulbar muscle involvement was almost exclusively observed in the recessive group. In conclusion, our study reports a large number of novel RYR1 mutations and indicates that recessive variants are at least as frequent as the dominant ones. Assigning pathogenicity to novel mutations is often difficult, and interpretation of genetic results in the context of clinical, histological, and muscle magnetic resonance imaging findings is essential.

ASEPTIC: primary antibiotic prophylaxis using co-trimoxazole to prevent SpontanEous bacterial PeritoniTIs in Cirrhosis-study protocol for an interventional randomised controlled trial.

BACKGROUND: Bacterial infection is a major cause of mortality in patients with cirrhosis. Spontaneous bacterial peritonitis (SBP) is a serious and common infection in patients with cirrhosis and ascites. Secondary prophylactic antibiotic therapy has been shown to improve outcomes after an episode of SBP but primary prophylaxis to prevent the first episode of SBP remains contentious. The aim of this trial is to assess whether primary antibiotic prophylaxis with co-trimoxazole improves overall survival compared to placebo in adults with cirrhosis and ascites. METHODS: The ASEPTIC trial is a multicentre, placebo-controlled, double-blinded, randomised controlled trial (RCT) in England, Scotland, and Wales. Patients aged 18 years and older with cirrhosis and ascites requiring diuretic treatment or paracentesis, and no current or previous episodes of SBP, are eligible, subject to exclusion criteria. The trial aims to recruit 432 patients from at least 30 sites. Patients will be randomised in a 1:1 ratio to receive either oral co-trimoxazole 960 mg or an identical placebo once daily for 18 months, with 6 monthly follow-up visits thereafter (with a maximum possible follow-up period of 48 months, and a minimum of 18 months). The primary outcome is overall survival. Secondary outcomes include the time to the first incidence of SBP, hospital admission rates, incidence of other infections (including Clostridium difficile) and antimicrobial resistance, patients' health-related quality of life, health and social care resource use, incidence of cirrhosis-related decompensation events, liver transplantation, and treatment-related serious adverse events. DISCUSSION: This trial will investigate the efficacy, safety, and cost-effectiveness of co-trimoxazole for patients with liver cirrhosis and ascites to determine whether this strategy improves clinical outcomes. Given there are no treatments that improve survival in decompensated cirrhosis outside of liver transplant, if the trial has a positive outcome, we anticipate widespread adoption of primary antibiotic prophylaxis. TRIAL REGISTRATION: ClinicalTrials.gov NCT043955365 . Registered on 18 April 2020. Research ethical approval was granted by the Research Ethics Committee (South Central - Oxford B; REC 19/SC/0311) and the Medicines and Healthcare products Regulatory Agency (MHRA).

Cardiac autophagic vacuolation in severe X-linked myopathy with excessive autophagy.

X-linked myopathy with excessive autophagy (XMEA), caused by mutations of the VMA21 gene, is a strictly skeletal muscle disease. Extensive studies in yeast established VMA21 as the master assembly chaperone of V-ATPase, the complex multisubunit proton pump that acidifies organelles and that is vital to all mammalian tissues. As such, skeletal muscle disease exclusivity in XMEA is highly surprising. We now show that the severest VMA21 mutation, c.164-6t>g, does result in XMEA-typical pathology with autophagic vacuolar changes outside skeletal muscle, namely in the heart. However, even patients with this mutation do not exhibit clinical extramuscular disease, including cardiac disease, despite extreme skeletal muscle wasting to the extent of ventilation dependence. Uncovering the unique skeletal muscle vulnerability to defective organellar acidification, and resultant tissue-destructive excessive autophagy, will be informative to the understanding of muscle physiology. Alternatively, understanding extramuscular resistance to VMA21 mutation might disclose heretofore unknown mammalian V-ATPase assembly chaperones other than VMA21.

MANAGEMENT OF TRAUMATIC LIVER LESIONS.

AIM: To determine the correct therapeutic approach to the different grades of liver trauma. MATERIAL AND METHODS: The study is based on a retrospective analysis of treatment outcomes in 56 patients with abdominal trauma admitted over a 9-year period to in the IIIrd Surgical Clinic of the Iasi "Sf. Spiridon" Hospital. It is focused on operative or non-operative management of liver trauma, surgical technique used, morbidity and postoperative mortality. Data were collected from electronic medical records and observation sheets and processed and interpreted using Microsoft Excel statistical functions. RESULTS: In the interval May 26, 2005-April 19, 2013 56 cases of abdominal trauma were recorded, 31 (55.35%) residing in urban areas, and 25 (44.64%) in rural areas. The mean age was 39 years, range 18-83 years old. The male/female ratio was 2.5/1 and the group consisted of 40 (71.42%) male patients and 16 (28.57%) female patients. The causes of abdominal trauma were: car accident in 29 (51%) cases, fall from different heights in 6 (10%) patients, workplace-related accidents in 8 patients (14%) and direct hit injury in 12 patients (12%). In our cohort, 51 (91%) patients with abdominal trauma have been emergency admitted, 3 patients (5%) were transferred from different medical units, and 2 patients (4%) were referred by a specialist doctor. Two or more simultaneous lesions were diagnosed in 53 (96%) cases. Of the 45 patients with traumatic liver injuries diagnosed on admission, 32 (71%) required surgical intervention. In the remaining 13 (29%) patients, the therapeutic management was conservative. CONCLUSIONS: Hepatic traumas are often severe, and frequently associated with multiple injuries. The non-operative management is indicated in liver lesions grade I, II and III according to the American Association for the Surgery of Trauma (AAST), if abdominal cavity organs are not injured. Higher grade liver lesions (over IV) in which the hemorrhagic risk persists or reappears require surgical intervention as soon as possible, and according to the type of lesion, the right procedure should be chosen.

No cardiomyopathy in X-linked myopathy with excessive autophagy.

In X-linked myopathy with excessive autophagy (XMEA) progressive sarcoplasmic accumulation of autolysosomes filled with undegraded debris leads to atrophy and weakness of skeletal muscles. XMEA is caused by compromised acidification of lysosomes resulting from hypofunction of the proton pump vacuolar ATPase (V-ATPase), due to hypomorphic mutations in VMA21, whose protein product assembles V-ATPase. To what extent the cardiac muscle is affected is unknown. Therefore we performed a comprehensive cardiac evaluation in four male XMEA patients, and also examined pathology of one deceased patient's cardiac and skeletal muscle. None of the symptomatic men (aged 25-48 years) had history or symptoms of cardiomyopathy. Resting electrocardiograms and echocardiographies were normal. MRI showed normal left ventricle ejection fraction and myocardial mass. Myocardial late-gadolinium enhancement was not detected. The deceased patient's skeletal but not cardiac muscle showed characteristic accumulation of autophagic vacuoles. In conclusion, in classic XMEA the myocardium is structurally, electrically and clinically spared.

A diagnostic dilemma in a family with cystinuria type B resolved by muscle magnetic resonance.

BACKGROUND: Congenital myopathies are inherited primary disorders of the muscle caused by mutations affecting structural, contractile, or regulatory proteins. In the more than 20 genes associated to these conditions, ryanodine receptor type 1 gene (RYR1) is responsible for the most common forms and is associated with a wide range of clinical phenotypes and pathological findings. Magnetic resonance imaging of muscle has been used increasingly to direct genetic testing in myopathies. PATIENT DESCRIPTION: We describe a consanguineous family affected by cystinuria type B, a metabolic condition linked to chromosome 19q13.2, and a different muscle phenotype that, although related to a congenital myopathy, does not have the striking histological features helping in direct genetic tests. RESULTS: The assessment of the selective involvement on muscle magnetic resonance imaging allowed the suspicion of RYR1 as the most likely gene responsible for this myopathy. The diagnosis was subsequently confirmed by the finding of a recessive RYR1 mutation. CONCLUSIONS: The occurrence of congenital myopathy together with cystinuria type B is reported for the first time. The use of muscle magnetic resonance imaging and the homozygosity by descent in SLC7A9, a gene flanking RYR1, allowed us to discover a new mutation in the RYR1 gene.

Loss-of-function mutations in MICU1 cause a brain and muscle disorder linked to primary alterations in mitochondrial calcium signaling.

Mitochondrial Ca(2+) uptake has key roles in cell life and death. Physiological Ca(2+) signaling regulates aerobic metabolism, whereas pathological Ca(2+) overload triggers cell death. Mitochondrial Ca(2+) uptake is mediated by the Ca(2+) uniporter complex in the inner mitochondrial membrane, which comprises MCU, a Ca(2+)-selective ion channel, and its regulator, MICU1. Here we report mutations of MICU1 in individuals with a disease phenotype characterized by proximal myopathy, learning difficulties and a progressive extrapyramidal movement disorder. In fibroblasts from subjects with MICU1 mutations, agonist-induced mitochondrial Ca(2+) uptake at low cytosolic Ca(2+) concentrations was increased, and cytosolic Ca(2+) signals were reduced. Although resting mitochondrial membrane potential was unchanged in MICU1-deficient cells, the mitochondrial network was severely fragmented. Whereas the pathophysiology of muscular dystrophy and the core myopathies involves abnormal mitochondrial Ca(2+) handling, the phenotype associated with MICU1 deficiency is caused by a primary defect in mitochondrial Ca(2+) signaling, demonstrating the crucial role of mitochondrial Ca(2+) uptake in humans.

Malignant tumors of digestive organs and liver metastases at the time of diagnosis.

AIM: Malignant tumors localized in the digestive tract have a tendency to local growth and invasion with lymph node metastasis. Distant metastases through blood with prevalent liver location are detected late in disease progression, in an advanced stage, when therapeutic possibilities are often limited to palliative therapy. MATERIAL AND METHODS: The study included a series of 139 patients with liver metastases admitted to the Center of Gastroenterology and Hepatology lasi between January 1 and October 10, 2011 for the identification of primitive tumor. The patients were investigated by endoscopy, imaging, laboratory tests including tumor markers. RESULTS: At 99 of the patients (71%) we identified primitive digestive tumors, in 19 patients (13.6%) we found tumors with extradigestive location and in 21 patients (15%) the primitive tumor could not be identified. Primitive.tumor was located in various segments of the digestive tract, liver, and pancreas was follows: esophagus 4 - (4%), eso-cardial-tuberositary 2 - (2%), eso-cardial-tuberositary with pancreatic invasion 1 -(1%), stomach 15 - (15%), ileocolon 1 - (1%), colon 19 - (19%), rectum 12 - (12%), liver, multicentric hepatolcellular carcinoma 23 - (23%) billiary tract - cholangiocarcinoma 2 (2%), pancreas 2 - (20%). In a series of 586 patients with malignant tumors of the digestive organs referred to the Iasi Oncology Outpatient Unit between January 1 and September 30, 2011, 132 patients (23%) had liver metastases at the time of diagnosis; the most common locations were the stomach 41% cases (42/119 patients), followed by the pancreas, 35%, and colon 31% patients (28/79 patients and 37/119 patients, respectively). Males were most affected, regardless of primitive tumor. CONCLUSIONS: Although diagnostic and therapeutic methods have made remarkable progress in recent years, these tumors, by their frequency and advanced stage at diagnosis, remain both an oncologic and public health problem mainly due to the limitations of curative treatment.

[Postoperative digestive fistulas. Etiopathogenic considerations]. / Consideratii asupra etiopatogeniei fistulelor digestive externe postoperatorii.

The digestive fistula is one of the most serious complications that might appear following different types of resectional digestive surgery. This condition still carries a considerable morbidity and mortality rate and therefore all surgical and ICU staff pay a great deal of attention and intensify their care to avoid the fatalities. The postoperative digestive fistulas, through their physiopathological and clinical complexity induce the disturbance of the biological equilibrium with vital consequences. The trend of the last decades is the increasing of digestive fistulas incidence with a variable mortality rate after different authors. A therapeutic algorithm is needed. The mortality rate due to digestive fistulas, two decades ago was, around 60%; at the present there is a decrease of the mortality rate, which is around 10%. The explanation is the introduction of the new methods of treatment such as lactic acid lavage aspiration for alkaline fistulas or total parenteral nutrition, continuous enteral nutrition and antiexocrine chemotherapy. A fistula is a communication between two epithelial or endothelial surfaces, lined by granulation tissue. It can be a life-threatening condition.

[General principles of clinical and therapeutic management in postoperative external enteral fistulas]. / Principii generale de management clinico-terapeutic in fistulele enterale externe post-operatorii.

Postoperative enterocutaneous fistulas represent a frequent complication in the emergency or cancerous digestive surgery. As to the high level of mortality and morbidity caused by this type of postoperative complication (4%), efforts are made to establish the principles of therapeutic management, on the purpose of decreasing these indicators and thus lowering the prolonged hospitalisation afferent costs.

[Intraoperative injuries of the biliary tract]. / Leziunile intraoperatorii de cai biliare.

Statistically speaking, the intraoperative lesions of common bile duct are rare clinical cases, but they have a high gravity potential. Our study was made on a lot of 11 operated pacients during 1995-2007 in our Clinic and it shows the tactical and technical approach used in solving these complications. The study also shows the high level of difficulty of these cases, as immediate recognition of this type of intraoperative lesions is needed. The successful evolution of these cases depends on how quickly the lesions are found and solved.

[Surgical therapeutic strategy in vital risk polytrauma with multiple organ injuries, case report]. / Strategia terapeutica chirurgicala in plagile cu risc vital cu leziuni multiple de organ. Prezentare de caz.

The medical interest for trauma pathology is incresing, due to the gravity of the given injuries. The surgical therapeutic strategy used is directly related to the localization and to the type of the trauma. The supplementary lesions and their vital risk also matter. The multidisciplinary team approach is the key to resolve this type of lesions with a good outcome. We recently observed an increasing tendency toward the rise of number and variety of patients with trauma, due to the great diversity of the etiopathogenic agents. The most important factor, during the assessment of a politraumatised patient is to diagnose correctly the functional deficits of vital organs and establish the vital prognosis. It is necessary to adopt the best and fast therapeutic strategy in order to obtain rapid life-saving decisions.

[Internal hernia--a rare cause of intestinal obstruction]. / Hernia interna--o cauza rara de ocluzie intestinala.

Internal hernia is rare its frequency ranging between 0.6 and 5.8%. It results from the protrusion of one or more abdominal viscera (usually small bowel) through an intraperitoneal opening. The opening can be normal (e.g. Winslow foramen), congenital (paraduodenal fossa, ileocecal fossa), or abnormal anatomical entities (after trauma or surgery). The clinical diagnosis of internal hernia is difficult because of the lack of specific signs and symptoms. There is a 63.6% lifetime risk of strangulation and bowel ischemia. In such cases, computed tomography is essential in the preoperative diagnosis because of the high mortality rate (20%) (which justifies its costs).