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Biomedical subjects

M Moroni

Publications and source records attributed to M Moroni.

At least 307 records · Page 17Linked to original sources
PubMedDate not supplied

Rabbit spermatozoa: a model system for studying ATP homeostasis and motility.

This paper studies the adenosine triphosphate (ATP) homeostasis and the motility parameters of rabbit spermatozoa. Rabbit sperm, collected by artificial vagina, were studied in various buffer systems to determine motility over time. Sperms were also extracted to measure enzyme activity. Analyses of motility by Computer Assisted Semen Analyzer system were run in parallel with energy metabolic studies of sperm cells maintained in different physiological solutions sometimes containing inhibitors of energy metabolism. Rabbit spermatozoa were shown to be able to form ATP either via glycolysis or via oxidative phosphorylation. Both these metabolic pathways were active in viable cells where creatine kinase and adenylate kinase systems were also present (1.1 and 7,000 nmol/min per 100 x 10(6), respectively) and involved in maintaining high ATP levels. A dynamic balance between ATP synthesis and ATP-hydrolyzing enzymes was suggested by the fact that rabbit sperms in their seminal plasma preserved their motility for hours. The decrease in sperm ATP content was mainly due to its hydrolysis by dynein ATPases coupled with movements. Therefore, motility of rabbit spermatozoa appeared to be dependent only on the ATP available to dynein ATPases. In fact, statistical analyses of motility parameters and the concentrations of intracellular ATP or ATP-metabolite did not show any significant correlation.

Adenosine Triphosphate↗
PubMedDate not supplied

Prevalence of HIV-1 resistant strains in recent seroconverters.

Twenty-nine HIV-1 recently infected subjects were retrospectively studied to investigate both the prevalence of nucleoside reverse transcriptase inhibitors (NRTI)-related mutations at primary infection and the proportion of naturally occurring mutations in protease inhibitor (PI)-naive patients. Neither HIV-1 plasma viremia nor CD4 absolute count at baseline could distinguish patients with NRTI pre-existing mutations from those with wild-type virus. An increasing proportion of ZDV-related mutations was observed over time with an overall frequency of 20.7% in the study period. Only 1 out of 6 patients (16.7%) with ZDV-related mutations showed a phenotypically ZDV resistant isolate. A striking proportion of polymorphic changes was present in the protease region of pol gene in newly infected individuals. As many as 80% of seroconverters presented at least one naturally occurring substitution. Some PI-associated substitutions, thought to be compensatory in protease enzymatic function, could confer intermediate to high PI-resistance. Their role following PI administration remains to be elucidated. Our data suggest that the choice of drugs should be oriented by both genotypic and phenotypic evaluations to tailor individual regimens in seroconverters.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Role of CCR5, CCR2 and SDF-1 gene polymorphisms in a population of HIV-1 infected individuals.

The finding that in addition to CD4 molecule HIV-1 uses, CCR5 or CXCR4 receptors to enter target cells prompted the research to identify polymorphisms in coreceptor genes affecting disease progression. In this study we analyzed the prevalence of CCR5-delta32, CCR2-641 and SDF1-3'A alleles in a highly selected group of 42 Long-Term Nonprogressors (LTNPs) compared to 112 subjects with a typical course of HIV-1 infection (TPs) and 117 healthy controls (HCs). In addition, we correlated CCR5, CCR2 and SDF-1 genotypes with molecular indexes of HIV-1 replication, cell-free RNA and both unspliced (US) and multiply spliced (MS) intracellular transcripts, to investigate the role of the mutant alleles in determining a long-term nonprogressive course of HIV-1 disease. Our results indicate a significantly higher prevalence of CCR5-delta32 allele in LTNPs compared to TPs (p=0.0434), while the proportions of CCR2-64I and SDF1-3'A alleles were comparable between the two groups. However, SDF-1 wild type LTNP subjects showed significantly lower levels of HIV-1 genomic RNA, US and MS transcripts than SDF1-3'A heterozygous ones (p=0.0021, 0.016, 0.0031, respectively), whereas both CCR5 and CCR2 wild type individuals had similar rates of viral replication compared to CCR5-delta32 and CCR2-64I heterozygous ones. CCR5, CCR2 and SDF-1 combined genotypes were also studied and this analysis did not identify a specific protective cluster of alleles in LTNPs. Taken together, our results indicate that genetic background involving CCR5, CCR2 and SDF-1 alleles may play a limited role in the natural history of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Primary HIV-1 resistance in recently and chronically infected individuals of the Italian Cohort Naive for Antiretrovirals.

The risk of acquiring HIV-1 drug resistance at time of infection has become a public health problem following the widespread use of antiretroviral drugs in developed countries. Although a number of studies have reported data regarding the prevalence of HIV-1 primary resistance in developed countries over the past years, limited knowledge is available regarding the proportion of mutations related to drug resistance in antiretroviral naive subjects with chronic HIV-1 disease. In this study, we evaluated the prevalence of mutations in the reverse-transcriptase (RT) and protease region both in a representative group of recently HIV-1 infected subjects (n=68) and a cohort of chronically-infected HIV-positive patients (n=347) enrolled in the Italian Cohort of Antiretroviral Naive patients (I.CO.NA.). In recently infected individuals, the overall prevalence of mutations for nucleoside RTI (NRTIs) was 10/68 (14.7%). The distribution of mutations by calendar year were 0, 1 in 1996, 9, 3 in 1997 and 1, 0 in 1998 for NRTIs and protease inhibitors (PIs) respectively. Thymidine associated mutations were identified in six subjects (8.8%), five of whom had one mutation [41L, 70K (n=2), 215Y] and one had two mutations (67N+219Q). Four subjects (5.9%) showed the changes associated with resistance to lamivudine (184V or 118I). No non nucleoside-RTI (NNRTI) mutations were present in the study period. Primary PIs mutations (two 46L and two 82I) were present in four subjects (5.9%). Of note, mutations related to resistance to more than one class of antiretrovirals were present in one (1.5%). Among patients with chronic infection a large proportion (88.5%) carried no mutations in RT region, 11.5% individuals carried one or more mutations associated with resistance to NRTI (7.8%), or NNRTI (4.9%), with 4 patients carrying mutations to both classes. Among mutations associated with high-level resistance to RTI, T215Y was found in only 2 patients, M184V in 2 cases, T69D in another case, and K103N in only 1 patient, for a total of 6 patients (one carrying both T215Y and M184V) (1.7%). Primary mutations associated with substantial resistance to PIs were found in only 5/347 patients (1.4%); all the other patients carried only secondary mutations. Prevalence of mutations associated with high-level resistance to antiretroviral drugs is stable in recently infected individuals and low in patients with established HIV infection. The potential impact of transmitted mutations on the response to first regimen in individuals carrying transmitted mutations needs to be assessed by prospective studies.

Acute Disease↗
PubMedDate not supplied

[Antibiotic therapy in bronchopulmonary infections].

Because of difficulties in accurately determining an etiologic diagnosis, the ideal treatment for lower respiratory tract infections remains questionable. Suggested regimens are made on the basis of clinical and epidemiological data. However, the single most common pathogen responsible for pneumonia remains Streptococcus pneumoniae. Atypical pneumonia in younger patients is best treated with macrolides. Older patients without debility or immunodepression are best treated with amoxycillin-ampicillin, second generation cephalosporins or cotrimoxazole, on the basis of local susceptibility patterns of microorganisms. In the treatment of acute bacterial bronchitis in chronic bronchial disease, most antimicrobial agents with activity in vitro against Haemophilus influenzae and Streptococcus pneumoniae are clinically efficacious. Among new pathogens, the importance of Chlamydia pneumoniae is variable according to the studies, and Moraxella catarrhalis was considered almost exclusively responsible for purulent exacerbations of chronic bronchitis. Therapy for empiric treatment of nosocomial pneumonia must ensure coverage for aerobic Gram negative bacilli: the most frequently used includes a semisynthetic penicillin plus an aminoglycoside, but monotherapy with newer broad-spectrum antibiotics (imipenem, ceftazidime, ciprofloxacin, timentin, etc.) seems to be equivalent to combination regimens. The lung is the most common target organ for infectious complications in immunocompromised patients but the diagnostic methods employed in the traditional work-up of pneumonia are often of little or no use in this setting. By far the two most useful clues to management of pneumonia in the immunocompromised host are the underlying host defect and the radiographic pattern of the lung infiltrate.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Splenic arteriovenous fistula (a clinical case)].

A splenic arteriovenous fistula is a situation often presenting with signs of portal hypertension and with a characteristic murmur. Though rare, the possibility of a splenic arteriovenous fistula must be borne in mind in differential diagnosis, since it can be corrected surgically by resolving the portal hypertension.

Adult↗
PubMedDate not supplied

[The risks of out of area missions: depleted uranium].

Depleted uranium (DU), a waste product of uranium enrichment, has several civilian and military applications. It was used as armor-piercing ammunition in international conflicts and was claimed to contribute to health problems, known as the Gulf War Syndrome and recently as the Balkan Syndrome. Leukaemia/Limphoma cases among UN soldiers in the Balkans have been related hypothetically to exposure to DU. The investigations published in the scientific literature give no support for this hypothesis. However future follow-up is necessary for evaluation of long-term risk.

Environmental Exposure↗
PubMedDate not supplied

[Eosinophilic infiltration of the gastrointestinal system: description of a clinical case simulating a lymphoproliferative process].

A case of diffuse eosinophilic infiltration of the gastroenteric tract which involved a large portion of the small intestine is discussed. It arose in a patient not previously affected with allergic traits and without eosinophilia in peripheral blood. Problems of differential diagnosis and clinical-therapeutic implications are reported.

Adult↗
PubMedDate not supplied

[Cystic mucinous neoplasms of the pancreas].

The Authors report on three cases of Mucinous Cystic Neoplasms of the pancreas. These tumours are rare and the diagnosis is based on echography and CT scanning. After a radical excision the prognosis is good although these tumours are "all" potentially malignant.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

[Travelers' diarrhea].

Travelers' diarrhea is an acute infection of the gastrointestinal tract which has been known for many years, but which only recently has acquired epidemiologic and economic importance. The etiology is multiple and includes bacteria, viruses and protozoa, but the most frequently found agent is enterotogenic E. coli (ETEC). The symptomatology is characterized by watery acute diarrhea, without mucus, inflammatory cells and blood, usually without febrile elevation. The syndrome is normally self-limiting, without any specific antibiotic therapy, while antidiarrheal agents reduce entity and length of the symptomatology. Antimicrobial therapy is indicated in persistent forms only after ascertainment of the etiologic agent.

Bacterial Infections↗
PubMedDate not supplied

[Microbiological specimen for anaerobic assay (author's transl)].

The most important events of the bacteriological study of the anaerobic infections are the choose of specimen, how to collect and carry it. These preliminary steps may condition the success of each further manipulation. A correct methodology requires some general rules: 1. to prepare anaerobic assay only whether the clinical data are indicative: so the laboratory could give better performances for the truly interesting cases; 2. to prevent, for what it is possible, contacts between 02 and the sample; to avoid contamination with anaerobic bacteria of the endogen flora present on human mucosa; 3. the sample must be assayed within 30--45 min after having been collected. After this time many bacterial cells are lost and the sample does not represent anymore microbiology of the septic focus. Indications about samples available for anaerobic assay, are given. It is emphasized how much preferable is a syringe collecting, while swab or biopsy present some technical difficulties and cause loss of the exigent bacteria. Some indication is at last given about the transport of specimen in the case the patient is not near the laboratory.

Anaerobiosis↗