Oxygen concentration in milk of healthy and mastitic cows and implications of low oxygen tension for the killing ofStaphylococcus aureusby bovine neutrophils

1988 ◽  
Vol 55 (4) ◽  
pp. 513-519 ◽  
Author(s):  
Susan J. Mayer ◽  
Avril E. Waterman ◽  
Peter M. Keen ◽  
Neil Craven ◽  
F. John Bourne

SummaryThe partial pressure of O2in milk from normal cows and from cows with mastitis was measured and the concentrations of O2calculated. Oxygen levels of milk from normal cows were similar to those in venous plasma, but inflammation of the mammary gland led to a dramatic drop in O2concentration to < 10% of control values. Intracellular survival ofStaphylococcus aureusstrain M60 in bovine neutrophils was greater under anaerobic than aerobic conditions. The implications of low O2concentrations in milk from infected mammary glands for the bactericidal activity of bovine neutrophils is discussed.

1984 ◽  
Vol 37 (2) ◽  
pp. 31 ◽  
Author(s):  
S S Mohapatra ◽  
PM GresshoffA

Nitrogenase activity can be detected in Rhizobium strain ANU289 of Parasponia in shaken liquid cultures. A combination of consistently low oxygen tension and appropriate cell density was found to be essential for rapid initiation and high specific rates (in the range of 50-60 nmoles of ethylene per milligram protein per hour). In the presence of succinate as carbon source and an oxygen concentration of 0�25% (v/v) in the gas phase, nitrogenase activity developed after incubation for 24 h. The requirement for an oxygen concentration in the range of O� 1 to 0�35% for derepression indicated a lack of any inherent tolerance to higher oxygen levels and thus suggests that plant-derived mechanisms are responsible for protection by oxygen in the nodule.


Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3047
Author(s):  
Jully Gogoi-Tiwari ◽  
Dorji Dorji ◽  
Harish Kumar Tiwari ◽  
Gayatri Shirolkar ◽  
Joshua W. Aleri ◽  
...  

Non-typeable (NT) Staphylococcus aureus strains are associated with chronic bovine mastitis. This study investigates the impact of biofilm formation by clinical NT S. aureus on cytokine production and mammary tissue damage by using a mouse mastitis model. Mice infected with two different NT S. aureus strains with strong and weak biofilm forming potential demonstrated identical clinical symptoms (moderate), minimal inflammatory infiltrates, and tissue damage (level 1 histopathological changes) in the mammary glands. However, the S. aureus load in the mammary glands of mice and the level of pro-inflammatory cytokines (IL-1β, IL-6, IL-12, IL-17 and IFN-γ) in serum were significantly higher (p ≤ 0.05) in those infected with the strong biofilm forming NT S. aureus strain. The level of IL-6 in sera samples of these mice was extremely high (15,479.9 ± 532 Pg/mL. Furthermore, these mice died in 24h of post infection compared to 30 h in the weak biofilm forming NT S. aureus infected group. The study demonstrates no association between the strength of PIA (polysaccharide intercellular adhesion)-dependent biofilm production by clinical NT S. aureus and mammary gland pathology in a mouse mastitis model. However, the role of biofilm in the virulence of S. aureus advancing the time of mortality in mice warrants further investigation.


2007 ◽  
Vol 74 (1) ◽  
pp. 29-31
Author(s):  
A.M.M.P. Della Libera ◽  
W.P. de Araújo ◽  
M.G. Blagitz ◽  
C.R. Bastos ◽  
M.R. Azedo ◽  
...  

ABSTRACT This is a case report on a nulliparous Toggenbourg goat, one year of age that, after being submitted to superovulation with human menopause gonadotrophin, presented mammogenesis and lactogenesis. Both neoformed mammary glands were naturally infected with β-hemolytic Staphylococcus aureus and evolved clinically in different forms. The left half evolved to acute catarrhal mastitis that responded positively to treatment using sodium cloxacillin, whereas right mammary gland evolved to phlegmonous gangrenous mastitis, with teat loss. The mammary tissue remaining had to be surgically removed. The present report emphasizes that multi-tissue effect should not be ignored when hormonal therapy is used. The potential risk of induced mammogenesis in nulliparous animals and the nosological diversity that mastitis may present should be considered, once the etiological agent and host were the same, and different inflammatory responses were observed in the two halves.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Luiz E. Bermudez ◽  
Laura Meek

Objective. Tuberculosis is a serious problem of public health. The increase on the number of clinical cases of tuberculosis infected with multidrug resistant (MDR)M. tuberculosiscalls for the development of novel therapy.Design. We investigated the effect of mefloquine and two enantiomers, (+)erythro-mefloquine and (+)threo-mefloquine againstM. tuberculosisstrains in the environment resembling the aspects of the granuloma environment and in macrophages.Results. The results suggest that mefloquine (racemic mixture) and (+)erythro-mefloquine have bactericidal activity againstM. tuberculosisstrains both in acidic, low oxygen tension and in macrophages. The activity, however, was impaired under increased osmolarity.Conclusion. Identification of the target for mefloquine in the pathogen will allow for the development of novel drugs with antituberculosis activity.


Author(s):  
M. Yu. Myasnyankin ◽  
V. V. Anisimov

Introduction. According to epidemiological researches, such mammary gland disease as fibrocystic breast disease takes the leading place in the structure of pre-tumor diseases in women. Pathological cell proliferation is the common starting point for pathogenesis of both mastopathy and breast cancer. Patients with fibrocystic breast disease complain of pain unrelated to the menstrual cycle in the area of the mammary glands, swelling of breast tissue, nipple discharge. An important problem is the effective treatment of mastitis and lactostasis, during and after which the possibility of breastfeeding was maintained. Mastitis is a formidable complication of the postpartum period and the cause of lactation failure. For a long time, all patients with infectious mastitis underwent surgical treatment of the area of infection with subsequent drainage. As a rule, with the prescription of broad spectrum antibiotic drugs. Often, against the background of such stress for the body the ability to breastfeed dies down. Timely diagnosis and adequate treatment of mastitis and lactostasis help to preserve breastfeeding and improve the health of mother and child. Treatment of mastitis and lactostasis, fibrocystic breast disease is a complex problem of modern mammology.Aim. This paper presents a pathogenetic approach to the treatment of fibrocystic breast disease from the point of view of evidence-based medicine using micronized progesterone. In order to avoid surgical interventions on the mammary glands and to preserve the maximum possible period of breastfeeding, we studied and proposed the method of mini-invasive and evidence-based approach to the treatment and prophylaxis of mastitis and lactostasis using a drug containing the strain L. Fermentum CECT5716.Materials and methods. 13 patients with mastitis symptoms were included in the study. The main complaint of all patients who applied was lactostasis (100%). According to breast ultrasound, most patients were diagnosed with infiltrative mastitis – 8 (61.5%), serous mastitis – 4 (30.7%). Only one patient was diagnosed with purulent mastitis (7.7%). After prescription of treatment for mastitis and lactostasis after 21 days of clinical and radiological mammary gland image in 10 cases (77%) without pathology, duct ectasia was found in three women, which is the physiological norm in breastfeeding. All breastfeeding women have recovered normal lactation without symptoms of lactostasis. Almost all patients according to pain VAS noted not exceeding 1 point (mean was 1 ± 0.7). In most cases, the punctate cytogram corresponded to acute inflammation and purulent inflammation, 7 (53.9%) and 6 (46.1%). Results of a bacteriological study: Staphylococcus aureus – 11 (84.6%). Three patients had mixed microflora, Staphylococcus aureus/Staphylococcus epidermidis and Staphylococcus aureus/Staphylococcus saprophyticus, 2 (15.3%) and 1 (7.7%), respectively. One patient was diagnosed with Enterococcus faecalis. These data affected the choice of therapy. All patients were prescribed therapy with a drug containing the strain of L. Fermentum CECT5716 one capsule per day for 28 days, with subsequent assessment of the therapeutic effect on the 10th, 21st days.Results. After treatment on the 10th day of control examination all the patients had galactorrhea cytogram without morphological signs of inflammation. According to the data of the bacteriological study of cultures, complete elimination of pathogenic microflora was revealed in most cases – 8 (61,5%), in 5 patients there were titers of less than 104 CFU/ml, which was the norm indicator. Clinical examples of treatment are given.Conclusions. Our experience in treating such patients with a drug containing the strain L. Fermentum CECT5716 can successfully replace the standard of medical care for the treatment of mastitis and lactostasis. However, a combination with antibiotic therapy can be used for high bacterial load and mixed microflora. In all cases (100%) on the 10th day after the start of therapy all symptoms and clinical and radiological signs of lactostasis and mastitis were cured.


Author(s):  
I.C. Murray

In women, hyperprolactinemia is often due to a prolactin (PRL)-secreting adenoma or PRL cell hyperplasia. RRL excess stimulates the mammary glands and causes proliferation of the alveolar epithelium. Bromocriptine, a dopamine agonist, inhibits PRL secretion and is given to women to treat nonpuerperal galactorrhea. Old female rats have been reported to have PRL cell hyperplasia or adenoma leading to PRL hypersecretion and breast stimulation. Herein, we describe the effect of bromocriptine and consequently the reduction in serum PRL levels on the ultrastructure of rat mammary glands.Female Long-Evans rats, 23 months of age, were divided into control and bromocriptine-treated groups. The control animals were injected subcutaneously once daily with a 10% ethanol vehicle and were later divided into a normoprolactinemic control group with serum PRL levels under 30 ng/ml and a hyperprolactinemic control group with serum PRL levels above 30 ng/ml.


1961 ◽  
Vol 36 (1) ◽  
pp. 141-156 ◽  
Author(s):  
B. Bengtsson ◽  
A. Norgren

ABSTRACT The effect of testosterone and oestrone on the mammary glands of castrated male rabbits was studied. Testosterone propionate was used in daily doses from 0.5 to 80 mg. The doses of oestrone ranged from 0.05 to 25 μg per day. Mammary glands were examined after 14, 28 or 56 days of injections. 1) Testosterone in doses below 20 mg failed to affect the mammary glands. With 40 or 80 mg a distinct, though abnormal growth reaction was consistently obtained. 2) Oestrone in doses lower than 0.5 μg did not stimulate mammary growth. With 0.5 μg and higher doses extensive growth of the mammary glands occurred. Stunted growth and secretion were found in the mammary glands of rabbits injected with 12.5 or 25 μg oestrone. 3) Testosterone in doses of 1 or 5 to 10 mg depressed or abolished the response of the mammary glands to 0.5 μg oestrone. When testosterone, in doses ineffective when given alone, was added to at least 3.125 μg oestrone, the mammary glands developed alveoli. The abnormalities produced by the highest doses of oestrone studied were exaggerated by the addition of testosterone. 4) The observations indicate a complicated interplay between the actions of testosterone and oestrone on the mammary gland of the rabbit. The interactions between testosterone and oestrone are presumably different from those observed between progesterone and oestrone.


1973 ◽  
Vol 73 (4) ◽  
pp. 700-712 ◽  
Author(s):  
J. D. Bruce ◽  
X. Cofre ◽  
V. D. Ramirez

ABSTRACT On the day following delivery (day 1 of lactation) one abdominal mammary gland was implanted with oestrogen and the contralateral gland received an empty needle. At 2, 5 or 10 days of lactation the rats were anaesthetized with pentobarbital and the nipples of both abdominal glands were cannulated and their pressures recorded by means of transducers coupled to an amplifier and recording system. The normal mammary glands of 5-day lactating rats responded to very low doses of oxytocin (Syntocinon®, Sandoz) (5× 10−8 mU) with a rhythmic elevation in pressure. However, saline infusion also evoked a small rise in intra-mammary pressure. Earlier (2 days) and later (10 days) in lactation the responses were smaller. Oestrogen decreases significantly the milk ejection response to oxytocin, and the effect was maximal at day 10 of lactation. Histological observations confirmed the diminished reaction of the gland to oxytocin, since the milk was retained in the alveoli of rats bearing a mammary-oestrogen implant. A paradoxical rise in pressure was detected in normal as well as in oestrogen-implanted glands when the lowest dose of oxytocin was injected in lactating rats which had previously received a high dose of oxytocin (50 mU or 500 mU). These results reinforce the hypothesis that oestrogen alters the milk ejection response to oxytocin and that the mechanism is probably related to changes in the contractility of the myoepithelial cells.


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