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Biomedical subjects

R Paniagua

Publications and source records attributed to R Paniagua.

252 records · Page 14Linked to original sources
PubMedDate not supplied

Testosterone immunoexpression in human Leydig cells of the tunica albuginea testis and spermatic cord. A quantitative study in normal foetuses, young adults, elderly men and patients with cryptorchidism.

A semi-quantitative study of the extra-parenchymal Leydig cells in the tunica albuginea testis and spermatic cord was performed on histological sections immunostained with anti-testosterone antibodies in the testes and spermatic cords obtained from human foetuses, adults and elderly men without testicular or related diseases (autopsy specimens), as well as from adult men with cryptorchidism (surgical specimens). The albugineal Leydig cells appeared in small groups in the vicinity of blood vessels. The Leydig cells of the spermatic cord usually appeared inside or around nerve trunks. The percentages of testes and spermatic cords with extra-parenchymal Leydig cells were higher in the cryptorchid testis group than in the normal male groups. The number of Leydig cells per mm2 in the tunica albuginea testis was higher in normal adult males than in foetuses. This number decreased in elderly men and increased markedly in cryptorchidism. The number of Leydig cells per mm2 in the spermatic cord was also higher in normal adults than in foetuses and it did not change with either advancing age or cryptorchidism. In foetuses, the percentage of cells intensely immunostained by anti-testosterone antibodies in the tunica albuginea and spermatic cord did not differ significantly from that found in the testicular parenchyma, whereas in the other three groups (adult, elderly, and cryptorchid men) the percentages of these cells in the tunica albuginea and spermatic cord were significantly lower than in the testicular parenchyma.

Adolescent↗
PubMedDate not supplied

The apical mitochondria-rich cells of the mammalian epididymis.

The morphology and function of the apical mitochondria-rich cells in the mammalian ductus epididymidis epithelium are revised. These cells are similar in all mammalian species studied. Apical mitochondria-rich cells are scarce (1-5 cells/100 principal cells) and are mainly found in the initial epididymal segments. Their morphology varies from slender cells that extend from the basal lamina to the epididymal lumen, to round cells that protrude into the lumen and are not in contact with the basal lamina. Their cytoplasm is more electron-dense than that of principal cells and contains more mitochondria which, in some species, are surrounded by rough endoplasmic reticulum cisternae. The adluminal cytoplasm displays a few short microvilli and contains many acid phosphatase positive vesicles. Apical mitochondria-rich cells differ from the principal cells in some histochemical features such as: (a) different lectin-staining pattern; (b) more intense reaction to the enzymatic activities: carbonic anhydrase, Ca(2+)-ATPase, peanut-agglutinin-sialidase, NADP dehydrogenase, succinate dehydrogenase, alpha-galactosidase and beta-galactosidase; (c) more intense immunoreaction to several cytokeratin types and to estradiol-related receptor protein; (d) weaker immunoreaction to epithelial membrane antigen and to retinol-binding protein. Although the function of the apical mitochondria-rich cells is still unknown, the following possible functions have been suggested: holocrine secretion; cooperation with the principal cells in epididymal reabsorption of testicular fluid; and acidification of epididymal fluid. Experimental results suggest that differentiation and maintenance of apical mitochondria-rich cells are not under androgen control and that these cells are sensitive to estrogen stimulation.

Animals↗
PubMedDate not supplied

Membranoproliferative glomerulonephritis associated with a mixed-cell germinal ovary tumor.

We describe a patient with membranoproliferative glomerulopathy associated with a mixed-cell germinal ovary tumor (embryonal and dysgerminoma components). Advanced renal failure ensued without remission of nephrotic syndrome after surgery. Five other cases of ovary tumor associated with glomerulopathy and reported in the literature are reviewed. The association between membranoproliferative glomerulonephritis and mixed-cell germinal ovary tumor has not been previously reported.

Adolescent↗
PubMedDate not supplied

Malakoplakia of the maxillary sinus.

The first case of malakoplakia in the nasal cavities is reported. The patient, a 21-year-old man, presented a polypoid formation in the left maxillary sinus that was removed and studied by light and electron microscopy. The polypoid formation consisted of pseudostratified epithelium surrounding a central myxoid tissue which contained fibroblasts, histiocytes, and small inflammatory infiltrates. The most relevant features were histiocyte accumulations containing 1 to 5-microns diameter granules which displayed a concentric multilayered configuration. Ultrastructural findings revealed three types of lysosomes within the histiocyte cytoplasm: phagolysosomes, intermediate bodies, and Michaelis-Gutmann bodies. Septate junctions between lysosomes were frequent. The etiopathogenesis of this lesion is discussed.

Adult↗
PubMedDate not supplied

Number and DNA content of hypertrophic spermatogonia in normal and cryptorchid human testes.

The number and the DNA content of hypertrophic spermatogonia were studied in normal and cryptorchid testes. The number of hypertrophic spermatogonia in cryptorchid testes is higher than in control testes at the same age. This finding suggests alterations in the spermatogonia of cryptorchid males. The results show a polyploid DNA content in more than 80% of hypertrophic spermatogonia in both normal and cryptorchid testes. There were hypertrophic spermatogonia with a DNA content between 2c and 4c (0.5%) and between 4c and 8c (9%). These spermatogonia might be cells in the S phase of the cell cycle.

Adolescent↗
PubMedDate not supplied

Nuclear bodies (sphaeridia) in Sertoli cells of a man with acquired immunodeficiency syndrome (AIDS) and testicular infection by cytomegalovirus.

Histological and ultrastructural study of an adult man with acquired immunodeficiency syndrome (AIDS) revealed multiple testicular lesions. The seminiferous tubules varied from dilated tubules with hypospermatogenesis, to tubules with Sertoli cells and a few spermatogonia, to necrotic tubules. The testicular interstitium showed abundant inflammatory infiltrates, some of them forming microabscesses. The Sertoli cells exhibited spherical intranuclear inclusions corresponding to both cytomegalovirus and sphaeridia. Some sphaeridia stained intensely with EDTA as granular and fibrillar portions of the nucleolus; however, many sphaeridia stained weakly as nucleolar fibrillar centers. These observations suggest that a Sertoli cell response to cytomegalovirus is the proliferation of nucleolar organizing centers that in some instances may transform to give rise to more or less abnormally developed nucleoli.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Changes in the number, proliferation rates, and bcl-2 protein immunoexpression of epithelial and periductal cells from rat epididymis during postnatal development.

To investigate 1) the correlation between the proliferative activity of epididymal epithelium plus myoid cells and the increase in the number of these cells and 2) the role of the basal epithelial cells in the renewal of epididymal epithelium, a quantitative evaluation of the proliferation of both epithelial cells and periductal myoid cells in the different epididymal regions (caput, corpus, and cauda) has been carried out during postnatal development of the rat by immunohistochemical evaluation of BrdU-labeling indices. These data were correlated with cell numbers and counted by the optical dissector method. The presence of bcl-2 protein was immunohistochemically detected and evaluated. No significant differences in BrdU indices were observed among epididymal regions in any stage studied. Cell proliferation decreased from the prepubertal period to adulthood in both epithelial and myoid cells in the three regions of the epididymis, suggesting a close relationship between epithelial and mesenchymal components. The numbers of both cell types were significantly higher in the caput than in the corpus and cauda in all stages studied, suggesting functional differences between regions. A negative linear correlation between proliferative activity and cell numbers was noted that might be related to regulation of the cell population size. Basal cells showed a lower proliferation rate than principal cells, but most of the immunoreactive bcl-2 protein, in pubertal and adult epididymides, was observed in basal cells. Therefore, these cells might comprise a low-proliferating and apoptosis-resistant population.

Aging↗
PubMedDate not supplied

Correlation between peritoneal equilibration test and dialysis adequacy and transport test, for peritoneal transport type characterization. Mexican Nephrology Collaborative Study Group.

OBJECTIVE: The aim of this study was to analyze the correlation between the peritoneal equilibration test (PET) and the dialysis adequacy and transport test (DATT) for peritoneal transport type characterization, and the degree of patients' acceptance for each test. DESIGN: Cross-sectional, observational multicenter study. SETTING: Five referral (tertiary) dialysis centers of institutional practice. PATIENTS: The study included 107 adult continuous ambulatory peritoneal dialysis (CAPD) patients with a prescription of four exchanges of 2 L per day, irrespective of age, gender, cause of end-stage renal disease, time on dialysis, nutritional status, or residual renal function. Patients on immunosuppressive therapy and those with cancer, hepatitis B, or HIV, and those having a peritonitis episode within the previous 30 days, or three or more episodes during the previous 12 months, were excluded. MAIN MEASURES: Peritoneal transport type as classified by creatinine and urea dialysis-to-plasma (D/P) ratios by PET and DATT. RESULTS: Correlation coefficients between D/P ratios for creatinine and urea, obtained for the PET and the DATT, were 0.73 for D/P creatinine and 0.96 for D/P urea. Patients were classified into high, high-average, low-average, and low transport categories according to the mean and standard deviation of D/P creatinine values obtained from the PET at 4 hours. These values showed excellent concordance with those generated from the DATT data (alpha = 0.82, 95% confidence interval 0.67 - 0.93). Nineteen percent of patients showed discordance in their category when classified according to the PET versus the DATT. Patients' acceptance was better for the DATT than for the PET, as evaluated with a questionnaire. CONCLUSION: The DATT is an easy, inexpensive, and reliable test to assess peritoneal transport type, and it also provides information about peritoneal clearance of solutes and ultrafiltration. The DATT has better patient acceptance than the PET. Since the DATT has only been validated for patients on a fixed CAPD daily schedule of 4 x 2 L, the results should be confined only to patients receiving such a prescription.

Adolescent↗
PubMedDate not supplied

Relationship between fill volume, intraperitoneal pressure, body size, and subjective discomfort perception in CAPD patients. Mexican Nephrology Collaborative Study Group.

OBJECTIVE: To determine changes in intraperitoneal pressure (IPP) when dialysate fill volume is increased from 2.0 L to 2.5 L to 3.0 L per exchange, and to evaluate the relationship with subjective discomfort perception. DESIGN: Cross-sectional survey. SETTING: Seven Mexican hospital-based dialysis centers. PATIENTS: Eighty-one adult patients on continuous ambulatory peritoneal dialysis (CAPD) without restriction criteria for age, gender, or time on dialysis, were studied. Patients seropositive for HIV or hepatitis B, and those with cancer or receiving immunosuppressive drugs were excluded. Participants were studied as outpatients. MAIN MEASURES: Blindly and in random order, 2.0-, 2.5-, and 3.0-L volumes of dialysate were infused consecutively. Body surface area (BSA) was calculated from patient height and weight. IPP was assessed with the patient lying supine, measuring the height of the dialysate column inside the peritoneal dialysis bag tubing. Blood pressure and subjective discomfort perception (using a visual analog scale of 0-100 mm) were also evaluated and registered after each of the three exchanges. RESULTS: The IPP rose with each increase of dialysate volume and was higher in males than in females for each fill volume level. For males IPP was 18.9 +/- 6.9, 20.8 +/- 7.1, and 22.9 +/- 7.5 cm H2O; and for females it was 16.5 +/- 5.7, 18.4 +/- 5.5, and 19.7 +/- 6.2 cm H2O for 2.0-, 2.5-, and 3.0-L fill volumes respectively (p < 0.01 among fill volumes and between genders). Intraperitoneal pressure showed significant negative correlation with the fill volume corrected for patient body size as reflected by the dialysate volume/ BSA ratio (r= -0.393, p < 0.01; r= 0.319, p < 0.01; and r= -0.274, p < 0.02 for 2.0-, 2.5-, and 3.0-L fill volumes respectively). Discomfort score rose as fill volume rose, with a median of 0, 2.5, and 13.0 for 2.0-, 2.5-, and 3.0-L fill volumes respectively (p< 0.001). It is interesting, however, that with 2.5-L and 3.0-L dialysate infusion volumes, 64% and 44% of the patients, respectively, had no discomfort at all. CONCLUSION: Dialysate volume increase is associated with higher IPP, which is modulated by the gender and body size of the patients. Although the mean discomfort score was higher with larger dialysate volumes, there was no significant correlation between discomfort and IPP or the dialysate volume/BSA ratio. Many patients had no discomfort with 2.5-L or even with 3.0-L dialysate infusions; theoretically, they can be treated with larger volumes.

Adult↗
PubMedDate not supplied

Identification of N- and O-linked oligosaccharides in human seminal vesicles.

The main oligosaccharide residues and the saccharide linkage in infantile and adult human seminal vesicles were studied by means of lectin histochemistry at light and electron microscopy levels. In adult glands, the epithelial cell cytoplasm and luminal content reacted positively to the following residues: (GlcNAc)n (WGA), Galbeta1,3GalNAc (PNA), GalNAcalpha1,3Gal (SBA), GalNAcalpha1,3GalNAc (HPA), Fucalpha1,2Galbeta1,4GlcNAc (UEA-I), and alphaL-Fuc1,6DGlcNAc-O-Melibiosc (AAA). The presence of intense staining in the luminal content suggest that glycoproteins containing these oligosaccharide moieties are secreted by epithelial cells. Adult epithelial cells also reacted to Neu5Acalpha2,6Gal (SNA), Neu5Acalphaa2,3Galbeta1,4GlcNAc (MAA), Galbeta1,4GlcNAc (DSA), branched mannose chains (ConA), Man1,3Man (GNA), and Fucalpha1,2Galbeta1,4GlcNAcFucalpha1,3GlcNAc (LTA) but reaction to these residues was weak (MAA, DSA, ConA, and LTA) or absent (SNA and GNA) in the gland lumen, which suggests that they belong to intracytoplasmic proteins. The chemical and enzymatic treatments used suggest that the residues recognized by SNA, MAA, PNA, DSA, HPA, and SBA belong to O-linked oligosaccharides; those residues localized by ConA and GNA have an N-glycosidic linkage, and those bound by WGA, LTA, UEA-I, and AAA are linked to both N- and O-oligosaccharides. In prepubertal seminal vesicles, reaction in the epithelial cell cytoplasm was similar to that observed in adults, except for GNA and HPA, which showed a weaker reaction. However, the lumen of prepubertal seminal vesicles showed intense reaction to WGA and SBA only. The chemical and enzymatic treatments suggest that the scanty glycoproteins secreted by the prepubertal glands belong to the mucin-type.

Adult↗
PubMedDate not supplied

Immunoexpressions of p21, Rb, mcl-1 and bad gene products in normal, hyperplastic and carcinomatous human prostates.

A comparative study of the expression of p21, Rb, mcl-1, and bad gene products, which are involved in the control of the cell cycle, was performed in normal, hyperplastic, and carcinomatous human prostates by means of a semiquantitative immunochemical study. This included Western blot, ELISA, and immunohistochemistry procedures. In normal prostates, immunoexpression of the four gene products was scanty or absent. In men with benign prostatic hyperplasia, immunoreactions to the four proteins studied were found in many epithelial cells and some stromal cells. In prostatic carcinoma, the immunostaining pattern was as in hyperplastic prostates but the numbers of both epithelial and stromal cells were higher. Present results indicate that immunoexpression of p21, Rb (both the phosphorylated and dephosphorylated forms), mcl-1, and bad gene products are markedly increased in prostates with proliferative alterations but that these proteins do not discriminate between benignant (hyperplasia) and malignant (adenocarcinoma) prostatic tumours, although immunoexpression is higher in prostatic carcinoma.

Adult↗
PubMedDate not supplied

Bone mineral content, 25-hydroxycalciferol and zinc serum levels in insulin-dependent (type I) diabetic patients.

To determine the relationship between bone mineral content (BMC), 25-Hydroxycalciferol (25OHD) and zinc serum levels in young insulin-dependent diabetics, we performed photon absorptiometry on a poorly controlled group of 22 patients. Zinc, 25OHD and alkaline phosphatase were measured in fasting serum. Ca, P, Mg, glucose and cAMP were determined in serum and in 24 hours urine collection. The diabetic group showed a significant decrease in BMC (less than 0.001) with raised urinary excretion rate of calcium (p less than 0.001). On the other hand, serum levels of zinc and 25OHD showed a significant decrease (p less than 0.001, both). We found a positive and significant correlation between glycosuria and urinary excretion rate of calcium (r = 0.77; p less than 0.001) and negative one for 25OHD and urinary excretion rate of calcium (r = -0.77; p less than 0.001). We conclude that decreased zinc and 25OHD serum levels in poorly controlled insulin-dependent (Type I) diabetic patients, in addition to raised urinary excretion rate of calcium, as result of the osmotic diuresis, contribute to bone loss in these patients.

25-Hydroxyvitamin D 2↗
PubMedDate not supplied

[Lack of the central pair of axial filaments in a case of short-tailed spermatozoa human teratospermia (author's transl)].

A case of short-tailed human spermatozoa is presented in a patient with severe teratospermia. The middle piece was generally short, showing abundant cytoplasmic droplets, disruption of the mitochondrial sheath and absence of some coarsed fibers. The majority of spermatozoa showed enlargement of the principal piece, reduplication of proliferation of the fibrous sheath, and disorganization as well of the axial filament complex as of the coarsed fibers. An abnormal great number of microtubules and coarsed fibers were frequently randomly scattered throughout the cytoplasmic droplet. A further abnormality, consisting in the lack of the central pair of axial filaments was relevant in a 70 p. 100 of spermatozoa. This latter abnormality could be or not associated with the former alterations.

Adult↗
PubMedDate not supplied

Epidemiologic and demographic aspects of peritoneal dialysis in Mexico.

OBJECTIVE: To assess some epidemiological and demographic aspects of peritoneal dialysis (PD) at the Instituto Mexicano del Seguro Social (IMSS), the major institution of social security in Mexico, that provides health care services for 57% of the Mexican population at the time of the study. STUDY DESIGN: A cross-sectional analysis of data about patients under peritoneal dialysis in 1992. DATA SOURCES: A national survey containing demographic data, dialysis modality, type of catheter, peritonitis and death rates, and questions on costs, medical staff, and physical facilities for PD in all of the hospitals of the IMSS. RESULTS: All hospitals returned the information requested. Intermittent peritoneal dialysis (IPD) was performed in 19 hospitals, continuous ambulatory peritoneal dialysis (CAPD) in 11, and both modalities in 90. In 61 hospitals, a special area was designed for PD; in the rest of them, beds from general internal medicine departments were used. All hospitals had a head for the PD programs; overall, teams had 240 physicians and 765 nurses for IPD, and 182 physicians and 313 nurses for CAPD. CAPD prescription was four 2-L bags/day. For IPD, patients were hospitalized once a week and received 28 manually performed exchanges of 2-L bags; the mean time of hospitalization was 2.7 days, and 878 beds were used. The number of patients receiving PD was 7785, with a prevalence of 199.6 per million population. Of them, 4011 were on IPD and 3774 on CAPD; 54% of the patients were males. IPD patients' mean age was 49 +/- 17 yr, and that of CAPD patients' was 42 +/- 17 yr (NS). Diabetic nephropathy was the most frequent cause of ESRD (44%). Infection was the most important complication detected. Rates of peritonitis were 0.5/patient/yr on IPD and 0.8/patient/yr on CAPD. Annual mortality rates without stratification for specific causes were 34% in IPD and 17% in CAPD. Mortality rates may have been influenced by malnutrition and cardiovascular complications of diabetes, but specific causes of death were not investigated. All of the PD programs costs were covered by the institution. The cost per patient was not calculated, but IPD is known to be more expensive, due to its higher hospitalization rate. CONCLUSION: In spite of its higher cost and mortality, the institutions still use IPD, not so much on medical basis, but as the only alternative available for patients with adverse environmental, social, educational, and economic conditions for CAPD or HD.

Adolescent↗
PubMedDate not supplied

[Soft-drinks and health].

OBJECTIVE: To analyze published papers about soft drinks use, and to describe possible health benefits, risks, and damages related to soft drink consumption. INFORMATION SOURCE: A search was done in the MEDLINE compact disks, from January 1970 to January 1997, with the keywords soft drink, beverages, carbonated beverages, cola, Coca-Cola and sweetening-agents. STUDY SELECTION: Ninety nine papers reporting health-related damages or benefits in clinical or experimental studies were reviewed. DATA EXTRACTION: All articles with a clear description of at least one beneficial or harmful effect related to soft drink consumption were considered. RESULTS: There were reports on 25 harmful effects and of 7 possibly beneficial effects. Data are classified in prophylactic and therapeutic uses, dental caries and other dental disorders, mineral metabolism disorders, acid-peptic disease, neoplasm, risk factors for cardiovascular disease, effects on central nervous system, reproduction, allergy, and miscellaneous. CONCLUSIONS: High prevalence of exposure and excessive consumption of soft drinks may represent a public health problem in Mexico. Data analysis shows that soft drink consumption may not be as harmless as generally believed. Many of the reports are anecdotal, without a suitable methodological design. A wide field for research is present in this area.

Caffeine↗
PubMedDate not supplied

Acute effects of soft drink intake on calcium and phosphate metabolism in immature and adult rats.

OBJECTIVE: To test the acute effects of the intake of a phosphoric acid containing soft drink on acid-base balance and on calcium and phosphate metabolism. MATERIAL AND METHODS: We studied 14 young adult male Sprague-Dawley rats aged 90 days, and 14 immature animals aged 30 days. Half of the animals in each group were randomly assigned to receive either tap water (controls), or Coca-Cola ad libitum for seven days. After this period, the rats were individually placed in metabolic cages to collect 24 hours urine, and they were exsanguinated by aortic puncture. Immediately, pH and ionized calcium were measured in whole blood. Creatinine, phosphate and total calcium were determined in the urine and plasma. Plasma levels of PTH, 1 alpha, 25 (OH)2 D3 and 25 OH D3 were measured by IRMA and RIA commercial kits. RESULTS: The animals receiving the soft drink, both adults and immature, developed significant hypercalciuria and hyperphosphaturia. In immature animals, the plasma pH dropped from 7.45 +/- 0.04 to 7.33 +/- 0.02 (p < 0.05) but did not change in adult animals. Ionized calcium dropped significantly from 1.06 +/- 0.04 to 0.80 +/- 0.06 meq/L (p < 0.05) in immature animals but not in the adult animals. Only immature rats developed significant reduction of 1 alpha, 25 (OH)2 D3 and 25 OH D3, whereas only the adult rats developed significant hyperparathyroidism. Immature animals showed more severe derangement of calcium and phosphate metabolism related to soft drink intake.

Acid-Base Equilibrium↗